US1023552A - Dual ignition system. - Google Patents

Description

R. H. CUNNINGHAM.

DUAL IGNITION SYSTEM.

APPLICATION FILED JAN.29,1910.

1,023,552, Patented Apr. 16, 1912.

2 SHEETS-SHEET I.

MHGNEYC! WINDING R. H. CUNNINGHAM.

DUALIGNITION SYSTEM.

APPLICATION FILED JAN. 29, 1910.

Patented Apr. 16, 1912.

2 SHBETSSHEBT 2.

ctyrulrblrcdfi 7 8 me wtoz WIMMCO/L l l l l 1 Barn- 323x 444/ wto'cneq RICHARD H. CUNNINGHAM, OF NEW YORK, N. Y.

DUAL IGNITION SYSTEM.

Specification of Letters Patent.

Patented Apr. 16, 1912.

Application filed January 29, 1910. Serial No. 540,781.

To all whom it may concern:

Be it known that I, RICHARD H. CUN- NINGHAM, a citizen of the United States, residing at the city of New York, in the borough of Manhattan and State of New York, have invented certain new and useful Improvements in Dual Ignition Systems, of which the following is a full, clear, and exact description.

My invention relates to that variety of so called dual electrical ignition apparatus in which the low resistance primary circuit of an induction coil is energized by current derived at discretion from a suitable battery or from a magneto alternating current dynamo.

My apparatus is adapted for use in means for producing electrical ignition in internal combustion en ines, for the production of high tension e ectric discharges, and provides means whereby in a dual system of ignition, the primary circuit of the induction coil when energized by the battery will be closed for a brief period of time just previous to being subsequently interrupted by the same circuit breaker that is employed to interrupt the magneto current.

Another object of my invention is to provide a device whereby the intensity of battery current supplied to the battery circuit of the coil may be limited to that simply necessary to energize the coil enou 'h to produce a secondary spark of sufficient E. M. F., and intensity to fire the engine at various speeds.

Another object of the invention is to produce a device and means whereby the occurrence of prolonged direct short-circuiting of the battery through the primary coil is prevented; or at least markedly minimized when the engine is stopped with the selective switch closed on the battery circuit.

Another object of the invention is to increase the eilicicncy of the battery side of the ignition and to permit an induction coil suitable for magneto actuation to be equally suitable for a battery current of a less mean voltage and thus avoid irregular fire or misliring at high engine speed when running on the butter);

1 have further devised means whereby vxlu-n starting the engine on the battery all danger of premature firing and consequent hack kick of the explosive gas which is undcrgoing compression in the cylinder, is

eliminated.

Lastly, means have been provided, properly safe guarded from arcing, whereby a suitable momentary or series of momentary high tension sparks may be produced in the proper cylinder of a resting multi-cylinder internal combustion engine containing an explosive mixture of gas under compression in one of the cylinders thereof.

Other novel features of my invention will be more fully described hereinafter and pointed out in the claim.

One practical embodimentof my invention is shown in the accompanying drawings, in which like characters of reference designate like parts throughout the several views.

Referring to said drawings: Figure 1 is a diagrammatic representation of a magneto circuit closing and interrupting device, an induction coil and container therefor and connections between the several parts. Fig. 2 is an enlarged front view of my magneto circuit closing and opening device with the casing cover thereof removed. Fig. 3 is a perspective front view of an induction coil container, the plan of connections between it and the magneto, and a front view of the magneto with the cover of the breaker box in position. Fig. 4 is a diagrammatic rep resentation of the battery circuit. Fig. 5 is a similar representation of the magneto circuit.

In Figs. 1 and 2 is shown a circular breaker box 1, which is adapted to be concentrically disposed about the axis of the magneto shaft. Pivoted to one side of the armature of this box is a spring pressed lever 2, the pivoting pin being at 3. At the free end of this lever, a contact point l, of platinum or other suitable conductive material is atlixed. A metal bracket 5, insulated from the containing metal box 1, is fastened to one side thereof by nuts 6, said n'uts being electrically connected thereto but insulated from the box. The bracket bears an adjustable contact. screw 7. provided with a platinum contact point 8, the latter being normally in contact with point 4 of the lever 2.

The armature shaft of the magneto curries upon the end thereof. an ovoid (Hill 9. the latter being keyed or otherwise secured to an extension 10 of said shaft. Extension ll) is the lead of the magneto winding, and is insulated from the shaft proper.

A metal bracket 11, preferably of brass,

is secured to the inner side of box 1, but is also insulated therefrom; and attached to bracket 11, but also in turn insulated from it, is a flat spring 12, hearing on its upper surface at the free end, a button 13 of fiber or other suitable insulating and resisting material. The bracket 11 is stepped as shown in Fig. 2, and to the middle-step is secured the somewhat stiffer spring 14. Contact points 15 and 16 are respectively provided at the free ends of springs 12 and 14, these points being normally separated by about one sixty-fourth of an inch. A lead 12 electrically connects upper spring 12, with a terminal 17, the latter also eing insulated from the metal box 1 and being provided with fixation nuts thereon. The lower spring 14 is in metallic connection with the bracket 11. is a roller 18 which bears against cam 9, and the position of this roller and button 13 of spring 12 are such that when the symmetrical ovoid cam rotates, for example, counter clockwise, one of the respective cam surfaces substantially in line with the long diagonal of the cam will act upon the button 13, forcin the two contacts 15 and 16 together, an then a few degrees later the cor-- responding opposite cam surface causes the elevation of lever 2, thereby separating contacts 4 and 8. As the cam continues to.rotate, the shorter diameter will approach alinement with the button 13 and contacts 15 and 16 will again separate, so doing before contacts 4 and 8 actually again touch each other by reason of the formation of the cam. terval during a half revolution of the shaft when both sets of contact breakers are closed.

Referring now to Fig. 1, the container 19 of the induction coil has upon one face there-' of the selective switch 20. On the bottom of said container are the terminals 21, 22, 23 and 24 which are connected by insulated wire respectively to terminals 25, 17, 10 and 6 of the magneto and circuit breaker. It should be here noted that terminal 25 is the remainin or grounded terminal of the magneto win ing. On the upper surface of the container, terminals 26 and 27 indicate the two ends of the primary winding 28. Terminal 26 is connected to terminal 21 by lead 29 while terminal 27 is connected to the fixed contact 30 of switch 20. Binding posts 31 and 32 are connected to the respective terminals of battery 33. Post 31 is also connected to the fixed contact 34 of switch 20; while post 32 is connected to external terminal 22. Fixed contact 30 of the switch is electrically connected to fixed contact 35 and also to terminal 27.

The rotatable member of the switch comprises a hard rubber hub 36 which carries upon the under surface thereof the sector 37,

Pivoted upon lever 2 There is therefore but one short in preferably of brass or bronze, and upon its outer surface the metallic sector 38, the sec tors being hence insulated from each other. Sector 37 is in metallic contact with the hollow brass shaft 39 which is rigidly inclosed by the hub 36, the fixed contact 30 also being electrically connected to said shaft. Fixed contacts 40 and 41 are respectively connected to the terminals 23' and 24. Within the container are two condensers 42 and 43 of different capacities; one lead of each of which is connected to 26. The remaining lead of condenser 42, that of the larger capacity, is led via the terminal 45 to the elongated fixed contact 43 of the selective switch 20. The remaining lead of the condenser 43, that of the small capacity, is connected to binding post 32.

An open circuit push button 46 is inserted in a connecting lead extending between wire 29, which electrically connects terminals 21 and 26, and the lead connecting condenser 43 and binding post 32. When the switch 20 is turned to the position marked: Bat. in Fig. 3, in which position it is also shown in Fig. 1, the cover being however removed, the course of the circuit at the moment that lever 2 is just about to be elevated by the cam is as follows: From the plus poleof the batteryto binding post 32, to terminal22, to terminal 17 on the magneto breaker box, through insulated lead 12 to spring 12, spring 12 being at that instant in electrical connection with spring 14. Hence, from the latter through spring 14, bracket 11 and lead 47 to bracket 5, thence through screw 7, contacts 84, to lever 2, thence along the latter'to magneto terminal 25 by way of the frame of the magneto, thence to terminal 21, wire 29, terminal 26 and through the primary winding to 27, and via the contact 30, segment 37 and contact 34 to binding post 31. The condenser 43 is thus across the point of break between contacts 4 and 8, which is the point at which it is best adapted to perform its function.

On the turning of the switch to utilize the magneto current,'which position is indicated by the letters Mag. in Fig. 3, the battery circuit is cut out; member 19 and the nut 6 become electrically connected by way of the switch, segment 37 of which engages contacts 40 and 41; and to terminal 27 by Way of the connection leading therefrom to shaft 39 and sector 37. Contact 35 is at all times connected with shaft 39, and contact 43 is correspondingly connected with terminal 45.

Considering the magneto circuit in detail: Current flows from the magneto armature winding to ground, thence for one branch of the divided circuit, from grounded terminal 25, through the connection leading to post- 21; thence to terminal 26 and through the primary coil to terminal '27, then through the connection leading therefrom to shaft 39 and segment 37. The other branch of the circuit includes the grounded pin 3, lever 2, contacts -t8, bracket 5, nut 6, connection spective branches reuniting at segment 37, which is in engagement with said contact. The entire current then passes through contact 40 from segment 37, through the lead therefrom to post 23 and thence to shaft extension 10, and back to the armature.

Condenser 42 is electrically connected with terminal 45, and hence when sector 38 unites contacts 35 and43, which latter is connected to terminal 45, the said condenser is thrown intothe circuit parallel I operating equally well therefrom to post 24, the re to the l the battery or the magneto be in use; the device operating when on the battery circuit to conserve the battery by keeping the circuit closed the shortest possible time, and when the magneto is in use; in such case serving to maintain the magneto in short circuited condition during the greater portion of the time. Hence in one case my breaker box permits a flow of current therethrough for an instant only, while in the other the current flow is maintained for an extended interval of time. In so far as I am aware there has never been any successful attempt heretofore to so oper ate a dual system of the kind in question and the results achieved are of value.

In starting an engine by the previously primary winding of the coil, as well as in described so called method of swinging,

shunt to the point circuit at 48.

of interruption of the not come to rest at the maximum point of y turned compression, the cam 9 will have its long axis more or less horizontal and will hence not cause electrical contact between springs 12 and 14; no current therefore can flow through the battery circuit and burn-outs are hence avoided. In that position, however, if the pressure button lithe pressed and quickly released, current passes mo mentarily from post 32 across the button to terminal 26, through the primary winding to 27, and thence connections to post 31 of the battery. A high tension current is induced in the sec ondary, which will, if conducted as usual to a distributer as indicated in Fig. 3, with a suitably proportioned distributing segment, pass to that cylinder of the engine whose piston has last passed completely over the point of maximum compression, and provided spark advancing and retarding mechanism have been properly designed and adjusted. will effect the production of the ignition spark in the said cylinder. Owing to the fact that condenser 43 isof suitable capacity and is in shunt with the contacts of the press button 4:6, the said contacts are sub jected to practically no arcing.

I have shown in Figs. 4 and 5 diagramby way of the switch that the relatively adjustable.

sibly far It is evident that with the switch turned i the lever the cam 9 will oscillate back and forth, posenough in the reverse direction for 2 to be elevated, but since the contacts 15 and 16 are not in contact when said cam is in that position, even if the switch is to battery position, no spark occurs the reversed motion of the cam contii'iues until the cam has so far rotated that contacts 15 and 16 may separate. As such a condition can be brought about only by the engine swinging backward completely over the center, a procedure that never occurs, it is evident that premature explosion of gas in the cylinders due to niistiined or irregularly produced sparks is eliminated, by the above described mechanism.

Having described my invention, What I claim, is:

In a dual system of electrical ignition, a circuit making and breaking device comprising a plurality of circuit breakers, and means for successively operating said circuit breakers, a switch, a battery, a ma neto and an induction coil primary win ing, the above recited elements being electrically connected up and so cooperating with said circuit making and breaking device that when the switch is in battery circuiting position, current will flow through said winding for but a small fraction of a recurrent time interval, and with the switch in magneto circuiting position, said device will perunless i init of maximum current flow through the matic representations of the respective batl in said battery circuiting position.

tery and magneto circuits which show at a glance the relative positions of the several elements in such circuit.

magneto armature during the major portion of said time interval, 'two of said circuit breakers being in series when the switch is Lure, in the presence of two witnesses.

I particularly wish to point out the value of my automatic circuit breaking device by the action of which I obtain ignition at the i proper instant in the engine cycle whether i RICHARD H. CUNNINGHAM. \Vitnesses \Viwo M. CiiAriN,

\VILLIAM (I. LARY.

Images