Jan. 7, 1947. W. J. SPENGLEr 2,414,000 Fillied March 3, 1942 2. Sheets-Sheet l

v- - w a26/, 9. syáce. 7-6- Fr G 2 BY -? 43-ycops- 4.7% AORNEY Jan. 7, 1947. W. J. SPENGLER 2,414,000 IGNITION SYSTEM Filed March 3, 1942. 2 Sheets-Sheet 2

4472/4.NVENTOR 3 7 7, 3alcoreATTORNEY dial/4 Patented Jan. 7, 1947 2414,000 UNITED STATES PATENT office IGNITION sysTEM Walter J. Spengler, Sidney, N. Y., assignor to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application March 3, 1942, Serial No. 433,174 13 Claims. (Cl. 123-148) - 2 This invention relates to ignition apparatus Fig. 4 is a detail view, with parts broken away, and more particularly to an ignition system for showing a portion of the shielding harness for multi- internal combustion engines and one bank-of-cylinders; and, radio shielding means therefor. Fig. 5 is a sectional view, with parts broken One of the objects of the present invention is away, taken substantially on line 5-5 of Fig. 4. to provide a novel, simple and effective ignition The single embodiment of the invention illus System for engines having a plurality of radially trated in the drawings, by way of example, is disposed, axially-extending rows of cylinders. adapted for use on an internal combustion engine Another object of the invention is to provide a, iO of the type wherein'several axially extending novel ignition system for engines of the above 0 rows of cylinders are radially disposed about character, whereby maximum safety against com a common (not shown), each of said plete or even destructive partial ignition failure rows comprising a plurality of cylinders in-line. is attained. As shown, the engine comprises seven rows of Still another object is to provide a novel igni six cylinders each, forty-two cylinders in all. tion system for multi-cylinder engines which is 5 Each cylinder has two diametrically disposed so constituted that the parts thereof may be Spark plugs 2 and 3 to provide the safety and most advantageously arranged and mounted on power afforded by double ignition. Each row of the engine from the standpoints of installation, cylinders is preferably surrounded by a cooling operation, inspection, adjustment and repair. jacket 4 for the circulation of a cooling fluid. A further object is to provide a novel system 20 A novel and simple system for generating and of radio shielding for the ignition wires of an in distributing high tension current to spark plugs. ternal combustion engine of the above type. i2 and 3 of engine iO is provided whereby the . A still further object is to provide a novel ig lengths of the high tension leads or conductors nition system which is so constituted and ar are kept to a minimum, thereby reducing capac ranged as to materially reduce the danger of ig 25 ity losses, the possibilities of ignition failures, nition failures and inefficiency at high altitudes and the radio shielding requirements. Likewise, in engines having large numbers of cylinders. the necessary parts or units of the present novel Another object is to provide a rovel system of ignition system are kept relatively small and are supercharging the chambers of an ig adapted to be relatively evenly distributed on the inition system to thus enhance the operating 30 engine, thereby conserving space and insuring characteristics of the engine at high altitudes. less air resistance and better balance and, hence, The above and further objects, and novel fea- . a minimum of vibration. Said system, in the tures of the invention will more fully appear from . form shown, comprises a double 5 for the following detailed description when the same supplying and distributing high tension current is read in connection with the accompanying 35 to both sets of Spark plugs 2 and 3 in each row drawings. It is to be expressly understood, how of cylinders ff. One suitable form of magneto ever, that the drawings are for the purpose of for this purpose is illustrated in U. S. applica illustration only and are not intended to define tion for patent Serial No. 433,175, filled on March the limits of the invention, reference being pri 3, 1942 by Jakob R. Frei for improvements in marily had for this latter purpose to the ap O magneto. . It is believed to be unnecessary to pended claims. show a magneto in detail in the present applica In the drawings, wherein like reference char tion, since the magneto, per se, does not consti acters refer to like parts throughout the several tute a part of the present invention. views, - v Each magneto 5 is preferably removably se Fig. 1 is a diagrammatic, isometric view of a 45 cured on a so-called mounting pad 6, which may portion of an engine embodying one form of the be integrally cast with the cone-like nose of en novel ignition system comprehended by the pres gine fo and has an opening 7 that receives the ent invention; driven end of the rotor shaft of the magneto. Fig.2 is a diagrammatic illustration of said Said shaft is drivably connected in any suitable ignition System as viewed from the front of the SO manner, preferably through an adjustable cou engine; . pling to an engine driven shaft (not shown) jour Fig. 3 is a diagrammatic view of said system, naled in a hollow boss 8 on the nose of the en with parts broken away, showing samples of the gine. The rotor of each magneto 5 may be con cylinders;electrical connections for one bank or row of structed in accordance with any of several well known and suitable designs and is rotated in any

2,414,000 3 4 suitable manner, such as in the manner pointed through a metallic manifold ring or tube 46 out above, in timed relation with the engine which is mounted on the nose of engine ?o in crankshaft between two ignition coils 20 and 2 Side of the circularly arranged 5. which are diagrammatically illustrated in Fig. 3. Tubes or conduits 45 may be detachably secured The primary windings 20a and 2a of said coils 5 to magnetos 5 as well as to the outer periphery are connected in circuit with circuit breakers 22 of ring 46, the connection at the magneto being and 23 in the usual well-known manner, said cir of the plug and Socket type for leads 43 and 44 cuit breakers being simultaneously and period to thus permit quick and easy assembly and dis cally opened and closed by a 24 that may be assembly. on the rotor shaft of the magneto, or otherwise 0. For the purpose of convenience and simplicity, Operatively connected thereto, for rotation in all of the so-called ground wires in ring 46 (two timed relation therewith for the purpose of caus for each magneto) are connected to separate ing high tension current to be induced in second terminals in the Socket portion 47 of a "Cannon' . ary windings of Said coils. connector or similar multiple plug and socket Secondary windings 20b and 2 b of ignition connector, the details of which are well-known coils 20 and 2, respectively, of each of the seven and, hence, not shown. The plug portion 48 of magnetos 5 are electrically connected by suit Said connector is secured to a flexible metallic able brushes to the rotating arms 25 and 26 of Shielding tube 49 housing the necessary exten 27 and 28, respectively, which are sions of said ground wires 43 and 44 from each housed in oppositely disposed portions 29 and 30 magneto. Tube 49 may be similarly provided at of the metallic casings of said magnetos. Dis its other end with a "Cannon' connector for tributor arms 25 and 26 may be operatively con ready connection to a Switch mechanism 50. nected to and driven Synchronously with the The latter, which does not, per se, constitute a magneto rotor, as is Common practice in the mag part of the present invention, is so constructed neto art, for conducting high tension current in that when the control lever 5 is in the illus predetermined sequence to circularly arranged, trated or off position, all primary windings 20a non-uniformly spaced contacts or terminals 3 and 2 fa of the magneto coils will be grounded and 32 in distributor blocks that are preferably through the Switch mechanism and, hence, ren mounted in removable sections 29a and 30a df der the magnetos inoperative for generating high the magneto casing portions 29 and 30, 30 tension current for distribution to Spark plugs Separate high tension leads 33 and 34 extend 2 and 3. When lever 5 points to 'I' on the from contacts 3 and 32 to spark plugs 2 and face of switch 50, only the coils for furnishing 3, respectively, through tubular metallic shields Current to spark plugs 3 on the exhaust side 35 and 36 (Fig. 1). Each of the latter prefer of the cylinders are grounded, thus permitting ably comprises a rigid tube 37, a short flexible the engine to run on a single set of spark plugs tubular section 38 connected thereto, and a short 22. When lever 5 is at 'E' only the coils for rigid section 39 provided with an internally furnishing current to Spark plugs 2 are ground threaded nut 40 for detachably connecting the ed, thereby permitting the engine to run on spark shield to the magneto casing portion 29a ar 30a plugs f3. With lever 5 pointing toward “B,' . (Fig. 4). Extending radially from each tube 37 40 full operation of all magnetos and, hence, ig are six flexible metallic conduits 4 provided with nition by both sets of spark plugs is permitted. means for detachably securing the same to Conduits 45 and manifold ring 46 may be con shielded spark plugs 2 and 3 in a manner well veniently referred to as a ground wire harness, understood in the art, one of said conduits being Said ring being secured to the nose of the engine shown in detail in Fr. 5. High tension current 45 by suitable brackets or the like in any manner conductors 33 and 34 are thus led from conductor Well understood in the art. Manifold conduit housings 29a and 30a where they are connected 49 may also be considered as a portion or ex to terminals 3 and 32 through manifold shield tension of the ground wire harness. This har ing conduits 38, 37, and individual conductors neSS Serves not only to protect the electrical coln branch off through flexible conduits 4 for elec 50 ductors contained therein and to prevent elec trical connection to spark plugs 2 and 3. trical and magnetic radiations therefrom, but, All free space in the distributor block housings as hereafter pointed out, may also be employed 29a and 30a and in shields 37, 38, 4 is preferably as a unit in a system for supercharging the filled with a yieldable insulating compound 42, magnetos and distributor chambers associated Such as polymerized cashew nutshell oil. The 55 therewith. latter may be injected in liquid form into the For the purpose of increasing the ease with space to be filled and is then reduced to a unitary which engine to may be started, the above yieldable solid by chemical reactions, a solid described ignition System may be supplemented which has good electrical qualities and is capable With a novel booster circuit, the current pro of withstanding high temperatures. Shields 37, 60 ducing ability of which does not depend upon 38 may be secured by means of suitable brackets the Speed of rotation of the engine crankshaft (not shown) to a suitable rigid portion of the as does the current Supplied by magnetos 5. engine structure. As shown, the booster circuit comprises a buzzer In order to provide simultaneous and simplified coil 52 which includes a primary winding 53, a control of the operation of all seven of the inag 65 Secondary winding 54, and buzzer contacts 55 netos (5 from a centralized and convenient and 56 (Fig. 3). Miovable contact 55 of booster point, means are provided for grounding all of coil 52 is connected to one end of primary wind the primary windings 20a and 2 fa in all of Said ing 53, and the other end of said winding is magnetos through a common control switch that connected to a battery 57 through a lead 58 may be located in the cockpit of an airplane or 70 which extends through the ground wire harness at Some other suitable location. From the un manifold 46 and is connected by means of plug grounded ends of the primary windings of the connector 47, 48 with a lead 59. The latter coils in each magneto, leads 43 and 44 are led branches off from shielding tube 49 at any suit from the magneto into a metallic shielding tube able point and has a operated switch 60 45 which is preferably flexible and, thence, 75 interposed therein so that the booster circuit 2414,000 5 s is, permitted to function only when the engine . The gas may be supplied directly into the mag starting mechanism (not shown) is in operation. neto casings from the ground wire harness, Stationary contact 56 of the booster coll is also which casings may be rendered relatively gas connected to a lead 6 which extends through tight by suitable sealing means around the shafts manifold ring 46. Lead 6 is extended through which extend therefrom, or the same may be "Cannon' plug 47, 48 and a wire in tube 49 to supplied into a gas-tight casing or hood sur switch 50, the connection thereof to said Switch. rounding each magneto. A small amount of being such that when the latter is in any of the leakage is, of course, desirable to permit proper three "on" positions, the primary winding 53 is circulation and, hence, prevent any undue ion grounded through the Switch to permit the Con O ization of the gaseous medium within the dis pletion of an electrical circuit containing said tributor chambers. However, if an inert gas is primary winding and battery 57 when starter employed, it is likely that very little, if any, cir operated switch 60 is moved to closed position. culation would be required. p When lever 5 of the switch is in off position, . There is thus provided a novel ignition system as shown, winding 53 is not grounded and, hence, 15 for engines having large numbers of cylinders the booster coil will not function even though. and particularly for such engines employing switch. 60 is closed. . . - double ignition in each cylinder. Having re The secondary winding 54 of booster coil 52 is gard for the large number of cylinders, the igni permanently grounded at one end and is con tion system provided is very simple from the nected at its other end to one distributor of each 20 standpoints of construction and installation and magneto 15 by means of a single although dis lends itself readily to inspection, repair and over continuous lead 62. The latter together with the hauling. Additionally, said system includes shielding therefor is divided into a plurality of simply constructed parts and units which are in sections 63 and one section 64. Each of the Sec terchangeable and which may be inexpensively tions 63 comprises a shielded insulated conductor 25 repaired or replaced in case of damage without having a plug connector at each end similar to removing the entire system, thus materially re that shown at the outer end of lead ducing the costs of operation and upkeep. The 33, 4 of Fig. 5; The plug connectors at the ad system is also novelly constituted by separable jacent ends of adjacent sections 63 extend into units which may be conveniently arranged on the sockets at opposed sides of portions or bosses 65 30 engine to minimize the lengths of high tension on distributor housings 29 and yieldably engage leads and, hence, minimize ignition losses and a conductor 66 (Fig. 3) which conducts high ten increase operating efficiency. The novel igni sion current from secondary winding 54 to a sta tion system comprehended also includes a novel tionary ring 67 in an insulating block mounted booster circuit for starting purposes. Further in distributor housing 29. From said ring the 35 more, the system provided ends itself to eficient current jumps across a short gap to a contact supercharging of the distributor chambers for 68 that rotates with distributor arm 25 and dis high altitude flying and is so constructed that tributes the booster current to contacts 3 for it permits of maintaining critical flash-over dis transmission to spark plugs 2 in the desired se tances relatively large without unduly increas quence (Fig. 3). The distributor contacts for. 40 ing the Space required by any of the parts or the booster current in the seven magnetOS 5 units. . . . are thus electrically connected in parallel with Although only a single embodiment of the in each other, thereby simplifying both the booster vention has been illustrated and described in de circuit, per se, and the radio shielding required tail, it is to be expressly understood that the in therefor. Section 64 or the booster circuit is sin 45 Vention is not limited thereto. For example, ilar to sections 63, except that one end thereof various changes in the design and arrangement plugs into the booster coil 52 for connection with of parts illustrated will now be apparent to those one end of secondary winding 54. skilled in the art and may be effected without As best illustrated in Figs. and 2, booster coi departing from the spirit and scope of the in 52 is mounted on the nose of engine to relatively 50 vention. For a definition of the limits of the near ground wire harness manifold 46. Leads invention, reference is had primarily to the ap 58 and 6 from the booster coil may be shielded pended claims. . by a tube or conduit 69 which may be detach What is claimed is: ably secured to the coil housing and the manifold 1. An ignition System for a dual ignition in ring. - - 55 ternal combustion engine with a plurality of For high altitude flying it becomes desirable to groups of adjacent cylinders comprising a plu maintain a pressure within the magnetos and rality of magnetos, a pair of ignition distribu particularly within the distributor chambers tors operatively associated with each of said mag thereof, which pressure is higher than the atmos netOS, and means Operatively connecting the dis pheric pressure surrounding the aircraft at high 60 tributors of each of said pairs to spark plugs altitudes. The magnetos of the novel ignition in the same group of adjacent cylinders of said system comprehended by the present invention engine. may be readily and conveniently supercharged 2. An ignition system for a dual ignition in for this purpose by the addition of very little ternal Combustion engine comprising a plurality extra equipment. The air or other gas, such as 65 of magnetos, each of said magnetos being adapted an inert gas, may be supplied to the magnetos to generate electrical current for firing spark through the ground wire harness 45, 46 from a plugs in a separate group of adjacent cylinders suitable pressure source, such as a tank of com of said engine, a pair of ignition distributors op pressed gas or a suitable pump 70 (Fig. 3). As eratively associated with each of said magnetos, shown, the output or pressure side of pump 70 70 and means operatively connecting the distribu is operatively connected to one end of manifold tors of each of said pairs to spark plugs in the ring 46. same group of adjacent cylinders. If desired, the supercharging gas may be 3. An ignition system for a dual ignition in passed through a suitable filter and dryer to re ternal combustion engine comprising a plural move any foreign matter or moisture therefrom. 75 ity of magnetos, each of said magnetos being

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2,414,000 7 adapted to generate electrical current for spark distributors, a source of booster current, and plugs in a separate group of adjacent cylinders, means including a conductor and a rotary con two ignition distributors operatively associated ducting element in each distributor for distrib with each magneto, and means operatively con uting current from said booster source, said con necting the distributors associated with each ductors being connected in parallel branches of magneto to spark plugs in the same group of an electric circuit including said booster source. adjacent cylinders, said magnetos and distribu 9. In an ignition System for an internal com. tors being so constructed and operated that Suc bustion engine, a Source of high tension current, cessive ignitions of charges in the engine cylin a plurality of distributors for distributing said ders take place in cylinders of different groups. 0. current to the Spark plugs of Said engine, each 4. An ignition system for a dual ignition in of said distributors comprising a conducting ele ternal combustion engine comprising a plurality ment, and means connecting said elements to of magnetos, a pair of ignition distributors op said source, said elements being connected in eratively associated with each of said magnetos, parallel with each other. and means operatively connecting the distribur 5 10. In an ignition system for an internal com tors of each of said pairs to spark plugs in the bustion engine having a plurality of radially dis same group of adjacently mounted cylinders of posed rows of cylinders, the combination of a said engine, said distributors being so operated magneto mounted on said engine adjacent each that successively firing spark plugs are located of said rows of Cylinders, each of said magnetos in cylinders of different ones of said groups of 20 comprising a distributor, and a radio-shielding cylinderS. harness for the high tension leads to a set of 5. In an ignition system for a dual ignition in spark plugs in each row of cylinders, each of ternal combustion engine comprising a plurality said shielding harnesses having the manifold of magnetos, each of said magnetos being adapted thereof connected directly to the casing of the to generate electrical current for firing Spark 25 magneto mounted adjacent the corresponding plugs in a separate group of adjacent cylinders row and extending therefrom along said row of of said engine, a pair of ignition distributors cylinders. t operatively associated with each of Said mag 11. In an ignition system for an internal con netos, means operatively connecting the dis bustion engine having a plurality of radially dis tributors of each of said pairs to Spark plugs in 30 posed rows of cylinders, the combination of a the same group of adjacent cylinders, a Source magneto mounted on said engine adjacent each of booster current, means in at least one dis of said rows of cylinders, a distributor on each tributor of each of said magnetos for distrib of two opposite Sides of each magneto, and a uting booster current to spark plugs connected radio-shielding harness on each side of each row to said distributor, and means for connecting 35 of cylinders for shielding the high tension leads said last-named means in parallel and to said to sets of spark plugs on opposite sides of each source of booster current. of said rows of cylinders, the manifold of each 6. In an ignition system for internal combus harness being directly connected to the casing tion engines, a plurality of magnetos, a distribu of the magneto adjacent the corresponding row tor having cooperable stationary and rotary con 40 of cylinders. ductors for distributing high tension current 12. In an ignition system for a radial type from each of said magnetos, a source of high ten internal combustion engine, the combination of a sion current, such as a booster coil, and means plurality of magnetos circularly arranged on said for connecting said stationary conductors in par engine, each of said magnetOS having at least one allel with each other and to said source of high (5 distributor operatively associated therewith, a tension current whereby current from said source single source of booster current, contact means is distributed by said distributors. in each of said distributors for distributing cur 7. An ignition system for internal combustion rent from said source to the spark plugs of said engines comprising a plurality of distributors for engine, said contact means including a ring-like distributing high tension current to the Spark SO stationary conductor in each distributor, and plugs in the engine cylinders, each distributor means for connecting Said conductors in paral comprising a plurality of spaced output termi lel with each other and to Said Source. nals and a rotating element adapted to trans 13. In an ignition system for a dual ignition mit high tension current to said output termi internal combustion engine having a crankshaft nals in predetermined sequence, a common Source 55 and a plurality of rows of cylinders extending of high tension current, conducting means in radially from said shaft, the combination of two each of said distributors in spark gap relation sets of spark plugs in the cylinders of each row, with said rotating element, and means connect a plurality of magnetos for generating high ten ing said conducting means of each distributor in sion current, and distributor means for distrib parallel with each other and in a circuit with 60 uting high tension current from each of said said common source of high tension current. magnetos to two of said sets of spark plugs in 8. In an ignition system for an internal Com the same row of cylinders, each of said magnetos bustion engine, a plurality of distributors adapted supplying current to spark plugs in different cyl to distribute high tension current to the Spark inders than each other magneto. plugs of the engine, a regular source of high ten sion current operatively connected to each of Said WALTER J. SPENGLER.