US1463956A - Assigmoe to the daytoit ezigihjeeb - Google Patents

Description

Aug 7, 11923. 11,463,95fi

J. H. HUNT IGNITION SY STEM Filed Jan. 2, 1918 3 Sheets-Sheet 1 MAW 26 5595 Aug; '5, 1923. v 11,463956 J. H. HUNT IGNIIIO SYSTEM Film Jan. 191s s Sheets-Sheet 2 Aug. :2, 1923. I 11 463.956

' J H. HUNT IGNITION SYSTEM Filed Jan, 2, 1918 3 Sheets-Sheet 75 l atented Z DAYTON, OHIUQASSIIGNOE T THEE DAYTON ET TGIB TEERTNQ GOMPANY, A CORZEQEATTUN 01E. OIHEEDQ y IGNITTU'N SYSTEIVI.

Application filed January 2, 1918. Serial No. 209,814.

To all whom it may concern:

Be it known that l, JOHN, H. HUNT, a citizen of the United States of America, residing at Dayton, cou'nty of Montgomery,

El and State of Ohio, have invented certain new and useful Improvements in Tgnition Systems, of. which the following is a lull, clear, and exact description.

This invention relates to ignition equipment for multi-cylinder engines and has tor its object the. provision of means for preventinp ignition upon, reversal of the engine. Further objects and advantages of the present invention will be apparent from the ta following description, reference being had to the accompanying drawings, wherein preferred embodiment of the present invention is clearly shown.

Jig. l is an end View of .l V-type engine having an overhead cam shatt'enclosed in a housing upon the ends or which are mounted ignition units embodying the present invention;

- Fig. 2 is a plan view of an ignition unit embodying the present invention, the distributor and distributor rotor being removed;

Fig. 3 is a wiring diagram showing in diagrammatic form the timer mechanism shown in Fig. 2. and also a diagrammatic representation of a distributor and of an induction coil, and electric connections between the several elements of the ignition unit;

Figs, 4- and 5 are diagrammatic plan views of the timer and distribulor rotor oi" the ignition unit, showing relative position during normal and reverse rotation of the engine, respectively.

Referring to Fig. 2 of the drawings, designates the ignition unit having a circular base 21, which is adapted to secure the unit in place upon the cam gearing housing oi the engine, as shown .in Fig. 1, which shows a multi cylinder V-typ-e engine having cam shafts placed above the cylinder heads. The usual end cover for the cam shatt gearinc; housing is replaced by the base 21, which serves as a support for a timer cup 24. The timer cup 24 is provided with bearings (not shown) for a central shaft 26, carrying at its upper end a timer cam 27 and distributor rotor 28.

The rotor 28 comprises an armiid of insulating material mounted on cam 27 and held in proper relation with the cam by means of thereof with the arms 65, 66 and 67 respeclocating pin 35, carried bv the cam and engaging recess formed in the rotor. Both the rotor and cam are secured in place upon the shaft 26 by means of a screw 36 engaging in a tapped hole- 36 in the end or the shaft 26. The cam 27 is broached as at 3? for the securing thereof upon shaft 26 in fixed relation. The rotor carries a metallic spr ng 88, which engages a rotary contact 39 of conducting material. The function of spring 38 will be described later.

all designatesa distributor track located above the timer cup anolconcentric therewith, in a manner which forms no part of the present invention, but which is described in the co-pending'ap lication of William A. @hryst and John Hunt, Serial No. 208,369, filed December 22, 191?. Metallic stationary contact elements 4-8 are located 4' upon the track, and are connected in proper ielation with the various spark plugs o-tthe engine.

Upon the bottom of the timer cup 2% is mounted a breaker arm'bracket 59,.by means of pins 60, 61 and62, extending through the bracket and timer cup; and by means or a stud 63 mounted in the timer cup and having: its uppen end threaded to engage a nut 64. The pinbOj e-xtends through a round hole in the bracket and serves as a pivot about which the bracket may be swung for adjustment, which will be described later, slotted apertures being formed in the bracket "for the reception of the pins 61 and 62, and for the stud 63.

lit will be seen that by loosening the nut 64, the bracket 59 may be swung about the pin to a desired position and may be secured by tightening the nut 64. The breaker arm bracket 59 carries breaker arms 65', 66 and 67, mounted upon posts 68 secured to the bracket,'but insulated there from. The arms 65, btiand 67 are provided.

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with contacts 70, 71 and 72 respectively,

which engage with stationary contacts 73, 7d and 7 5 respectively, which are adjustably mounted upon upturned cars 76, formed integral with the bracket 59. Springs 77, 78 and 79 are electrically connected at one end with the member 58 and at other portions tively. -Thesprinn's serve to keep the stationary and movable contacts in touchingrelation, except at such times when the cam co-operating with the fiber 'tollowers 80, 81

m f incense and 82 will cause thepairs of contacts to prevent rebound or chattering when F6V0lV ing high speeds. This feature, however, forms no part of the present invention, but is full described and claimed in the patent A of J. Hunt, No. 1,426,873, issued August A. resistance coil 84, supported upon a spool 85 ot nonconducting material, is1nprimary'winding, and 118 the secondary winding of the induction coil carried by a base 106 in any suitable manner. One end of the primary winding 117 is connected by wire 125 with binding post 125 carried by base 106. The other end of the primary 117 and one end of thesecondary 118 are connected together by a wire 12-6, which is connected with binding post 127, by means of wire 127. The other'end of secondary 118 is connected with a metallic button 120,

carried by the base 106.

The circuits through; the ignition unit are shown diagrammatically in Fig. 3, with a single source of current supply. rent from the battery 130, grounded on the motor base, passes through connections 54, 12?, 127 and 126, through the primary Winding 117, and connections 125, 125*, and

54, to the connecting plate 58, from'whichare taken four parallel circuits. One circuit is formed through the breaker arm 05, contacts and T3, to the distributor base which forms a ground connection on the engine; a second circuit is through resist' ance 81, breaker arm. 67, contacts and T5, to ground; a. third circuit is through breaker arm (56, contacts 71 and Tel, to ground; and the fourth circuit is through wire 89, condenser 88 to ground.

One end of the secondary circuit 118 is grounded through the battery or through the timer, and the other end may be connected wit-h the rotor 28, as by button 12$) contacting with spring 38. This connection is indicated diagrammatically by wire 129 The cu1= Attention is now directed to Figs. a and 5-. The arrows'in Fig. l indicate the direction of rotation of the camand distributor rotor when the engine crank shaft is rotating in the normal direction. Tl e arrows in Fig. 5 indicate the direction of rotation of these elements upon a reversal of the engine. Fig. 4 shows the relative position of the cam and cam followers just before the camtouches followers 80 and 81, and after en-' gaging follower 82. it will be noted that upon rotation of the cam in the normal direction, contacts 72 and 75 will separate bc fore contacts 70, 73 and contacts 7 1 and 71. Cont- acts 70, 73 and Ta and 71, are so located withrespect to the cam that scparation is effected simultaneously.

Adjustment to bring about this simultaneous separation is effected by means of the adjustable breaker arm bracket previously described. lt will be seen that by rotating the bracket 59 about pin 00, the edges of cam followers and 81 maybe brought diametrically opposite to one another, so that both followers will be ci'igaged by the cam lobes at the same time. This adjustment oft'ollowers 80 and 81 will not aiiect the relation of follower S2 to the cam, for the reason that follower 82 is the same distance from pin 60 as the center of cam 27. Hereafter breaker arms and 60 with their parts co-operating therewith, will be known as main circuit breakers. 'lhe breaker arm 67 with its cooperating parts will be known as the resistance circuit breaker since resistance 8 is-included-between the breaker arm and the connecting plate 58. Two main circuit breakers are used so that in of faulty adjustment of the breaker contacts. two chances are await able of obtaining perfect contact during the period oi closing of the primary circuit.

Upon reference to Fig. 5, it will be noted that upon reversal of rotation of the cam, the main circuit breakers open before the resistance circuit breaker opens. Referring again to big. a, it will be noted that just as the main circuit breakers open, the distributor rotor will be in contact with one of the stationary contacts a3, while, referring to Fig. 5, it will be seen that upon a reversal of the engine, the resistance circuit breaker will be closed when the main circuit breakers are open, with the result that all of the primary current must now pass through the resistance 8%. \Vhen these conditions are present, the current in the primary will not only be greatly reduced, but the change in intensity of the magnetic field surround ing the induction windings will take place at a much slower rate than when the con: denser only is in parallel with the main circuit breakers, with the result that the voltage induced in the secondary is greatly reduced so that no spark would jump at the spark plug, were the greatly reduced sparking impulse to be distributed thereto.

As an extra precaution against sparking upon a reversal of theengine, the distributor rotor is so arranged with relation to the cam that at the time when the much e-nfeebled sparking impulse isinduced in the secondary, the rotor will not be in contact -with any one of the stationary contacts 13,

but there will be a gap between these ele-' ments as shown in Fig. 5. i

When the circuit is finally broken, upon the separation of the contacts of the resistback-firing of the-engine upon a reversal of rotation is afforded.

The timer is rendered ineffective to break the primary circuit in such a manner as to induce a current in the secondary of suthcient strength to cause sparking, and the distributor is rendered ineffective to distribute even the much weakened sparking impulse which may be created upon reversal of the engine. Therefore, the possibility of serious accidents and of damage to the engine, attendant upon back-firing, often occurring when the engine is started by rocking the propeller against compression, has been eliminated in a thoroughly reliable manner.

1 shows an end view of a multi-cylinder engine 136, which is of the V-type, consisting of a crank case'13'? upon which are mounted rows of cylinders 138 having their axes arranged at an angle of 45 degrees. 139 designates the crank shaft, and 140 and lell designate the cam shafts, the overhead cam shafts operating valves (not shown), which.

control the inlet and exhaust ports of the cylinders. The'cam shafts are driven from the crank shaft 139, by means of a gear 142, connected to the crank shaft, which drives the gear 1 13, mounted on a vertical shaft 144, which carries a gear 146.

A shaft is connected with shaft 1 M so as to drive a generator 135 for charging the battery 130, shown in Fig. 3. Thebattery charging circuit is disclosed in the -co pending application Serial No. 208,369, to which reference has been made.

Gear 146 meshes with gears 147 and 148, mounted on shafts 149 and 153 respectively, which are supported by pedestals 150 and 154: respectively. Shafts 1&9 and 153 carry at their upper ends gears 151 and 155, which mesh with gears 152 and 156, mounted upon the cam shafts 1 10 and 141 respectively. The relative size of the gears just described is such that the cam shafts will rotate at one-' half engine speed. Cam shafts 1 10 and M1 and the gearing co-operating therewith are inclosed in housings (not shown). Upon the ends ofthese housings are mounted ignition units 20 and 20 the bases of which serve as covers for the housings.

The act of mounting'the ignition units upon the 'cam'shafthousings accomplishes the connection of the timer cam shafts 26 with camshafts 140 and 141 and also accomplishes the making of an electrical connection between the ignition unit and the engine frame, upon which the source of ignition cur-' rent supply is grounded. The timer arms 93 are connected together by means of rods 15'? and 158, having threaded engagement with an intermediate turnbuckle 159. The rod connected with the arm 93 of unit 20*, is

operably associated with any controllinglever within easyreach of the operator, by means of which the timer cups may be shifted about their respective axes, vtoefiect advance or retard of the ignition. By adjusting the distance between the points of connection of rods 15? and 158, with arms 93, by 'ineans of turnbuckle 159, the time relation of the two units may be synchronized;

A high-tension conduit 163 mounted upon the intake manifold 16% serves asa housing for the high-tension cables leading from the distributor units 20 and 20 to the various spark plugs of the engine. Each engine cylinder is provided with two spark plugs so that in a 12-cylinder engine there will be two sets of spark plugs, twelve spark plugs in each set. One set of plugs is connected with the unit 2C" by means of the high tension cables 161, and the other set (if spark plugs is connected with ignition unit 20" by means of high-tension cables 162. In. the embodiment of the invention disclosed there are in fact twelve, each of cables 161 and 162, but

for the sake of clearness but two each of said cables 161 and 162 are shown.

It will be noted that the c in 27 is provided with asymmetrical lobes The reason for this is thatrthere ma be provided a 7 continuous series of sparking impulses of equal intenslty, but 1n asymmetrical succes- V sion in order to provide ignition for the en gine disclosed having asymmetrical firing order. This feature does not form a part of the present sole invention, but is-descrlbed in detail and claimed in the co-pending application of William A. Chryst and John H.

'Hunt, Serialhlo. 208,369, filed December 22,

The distributor contacts 43 must also be asymmetrically spaced in correspondence with the timer cam lobes in order to distribute properly the sparking impulses to the engine having two rows of 6 cylinders in each row, and the axes of the two rows converging from the crank shaft at an angle of 45 degrees, the firing intervals are d5 degrees and degrees or crank shaft rotation alternately. in the ignition timer which operates at one-hall engine speed, the spacing of the cam lobes and distributor contacts is'QFZ-l; degrees and 37; degrees, alternately. This particular arrangement is substantially shown in the drawings:

While there been shown but one condenser in the primary circuitof the ignition unit, is understood to be within the province of this invention to provide a plurality of condensers in parallel, so that any oil the condensers fail to operate, the remaining condensers will still be effective.

While the form of mechanismherein shown and described constitutes a preferred form-oi embodiment of the invention, it is m to be understood that other forms might be adopted, all coming within the scope oil the claims which follow, I

/V hat I claim is as follows:

L ln an ignition system for internal-combustion engines, the combination with means for producing sparking impulses, which upon normal operation oi the engine .Wlll provide ignition; of means operating upon reversal of the engine for weakening the sparking impulses to a degree such that ignition will not be provided;

2. ln an ignition system for internal combustion engines, the combination with means for producing sparking impulses, said means including an inductive winding and provisions, operable during normal engine rotation, for producing a relatively rapid change of magnetic flux in the region of said Winding; of devices, operating during a reversal of engine rotation, for eii'ecting a relatively slow change of magnetic fiuzr in the region of said winding.

3.. ln an ignition system for internal combustion engines, the combination with means for producing sparking impulses, said means including a secondary inductive winding, a current source, a primary inductive winding and provisions operable during normal-engine rotation to obtain a relatively quick ire-- ductionof current in said primary winding; of devices, operating during a reversal of engine rotation, for eilecting a relatively slow reduction 01 current in said primary winding.

In an ignition system "for internal c'ombustion engines, the combination with a primary circuit for creating a magnetic field, and a secondary circuit in which is induced a current upon achange in the intensity of the field; of means for causing a decrease of flux at a maximum rate during normal operation; and means operative upon a reversal of the engine for causing the decrease or flux to the field; of means for causing a decrease oi flux at a maximum rate during normal operation causing the induction or sparking impulses; means operative upon a reversal of the engine for causing the decrease of flux to take place a slower rate, whereby the voltage induced in the secondary is reduced to a value less than that required to cause a spark in the engine cylinder; and means for distributing sparking impulses to the engine cylinders upon normal operation of the en gine, said distributing means being inoperative upon reversal of the engine to distribute the weakened sparking impulse to any of the engine cylinders.

6. In an ignition system for internal-combustion engines, the combination with a cursaid coil; and means effective upon a reversal of the engine for obtaining a comparatively slow dissipation oi the energy of: the coil whereby said timer will be inefiective to cause said coil to provide ignition for said en in e. 1 Y

Z, In an ignition system for internalcombustion engines, the combination with a current source and an ignition coil; 0t engine controlled means controlling delivery of current to said coil for causing said coil to provide ignition during nonnalengine operation, but including provisions during a reversal of engine operation to produce a relatively slow dissipation of energy in said coil before the current in said coil is interrupted, whereby said coil cannot provide ignition for the engine.

8. lln an ignition system for internal-combustion engmes, the combination of means for producing a series of sparking impulses in. predetermined sequence bearing, during normal engine operation, a certain time relation to the engine cycle, but a difierent time of relation upon reversal of the engine;

means for distributing to the various spark plugs in similar sequence during normal engine rotation, but inoperative to distribute when the impulse producing means operates upon reversal of the engine; and means-operative upon reversal of the engine to weaken the sparkin impulses, whereby the tendency of the distri utor to function is gradually reduced.-

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ltlll Stll reversal; and means operating during a re-. versal of engine operation to produce. a rela-fltively slow dissipation of energy in said coil' before the current in said coil is interrupted;

by the timer, whereby said coil cannot pro vlde ignition for the engine.

1O. In an ignition system for internalcombustion engines, the combination with means for producing a series of sparking impulses in predetermined sequence bearing, during normal engine operation, a certain time relation to the engine cycle, but adifi'erent time relation upon reversal of the engine; means including a rotating contact and sta'- tionary contacts for distributing the sparking impulses to the various engine cylinders in similar sequence during normal engine rotation, but operating upon reversal in such a manner that, at the time when a sparking impulse would be created, a gap will exist between the distributor rotating contact and a stationary contact and means operative upon reversal of the engine to weaken a spar-king impulse, whereby the tendency of the sparking impulses to jump said gap is greatly reduced.

11. In an ignition system for internal combustion engines, the combination with primary and secondary circuits, a source of current in the primary circuit, and means for making and breaking the'primary circuit during normal operation of the engine for creating sparking impulses in the secondary circuit; of means for rendering said primary circuit breaker ineflective to" break the primary circuit during the reversal of the engine, at a time when a sparking impulse, it created, would be etiective to ignite.

a charge of gas in the engine. 7

12. In an ignition system -for internal combustion engines, the combination with primary and secondary circuits, a source of current in the primary circuit, and means for breaking the primary circuit during normal operation of the engine for creating sparking impulses in the secondary circuit; of means operating upon reversal of the engine to place a shunt circuit around said prlmary circuit breaker at a time during "erersal beforethe primary circuit breaker is opened.

13. in an ignition system for internal combustion engines, the combination with primary and secondary circuits, a source oat current in the primary circuit, and means for breaking the primary circuit during normal operation ofthe engine for creating sparking impulses in the secondary circuit; of means operating upon reversal of the en gine to complete the primary circuit through a resistance at a time during reversal before the primary circuit breaker is opened,

14;. lln arr-ignition system for internalcombustion engines, the combination with primary and secondary circuits, and a source of current in the primary circuit; of a main :circnitbreaker in the primary circuit'; means for opening the; main circuit breaker; a resistance circuit shunted around the main circuit breaker; and means for breaking the resistance circuit, the latter means operating duringnormal operation of the engine before the main circuit breaker opened. and operating during a reversal after the main circuit breaker is opened.

15.111 an ignition system for internal combustion engines. the combination with primary and secondary circuits, and a source of current in the primary circuit; of p a main circuit breaker comprising movable and stationary contacts; a resistance circuit shunted around the main circuit breaker, .includinga breaker for the resistance circuit which comprises movable and stationary contacts: and a common means for moving the movable contacts in recurrent sequence, so that during normal operation of the engine, the resistance circuit breaker will be in open position when the main circuit breaker opens, and so that during a. reversal. the resistance circuit will be closed at the time when the main circuit breaker opens.

16. In an ignition system for internal combustion engines. the combination with primary and secondary circuits, and a source of current in the primary circuit; of a plurality of main circuit breakers in parallel in said circuit; a resistance circuit in-the primary circuit connected in parallel with the main'ocircuit breakers, said resist ance circuit including a circuit breaker, each of'said breakers including stationary and -movable-contacts and common means for main circuit breal, ers are opened when the resistance circuit is closed.

17. in an ignition system for internal combustion engines, the combination with primary and secondary circuits. and a source of current in the primary circuit; oi. a main circuit breaker in said circuit; a resistance circuit shunted around the main circuit breaker, including a breaker for the resistance circuit, said circuit breakers including stationary and movable contacts; an engine driven member having means for moving the movable contacts in timed relation to the engine, such that during the normal operation of the engine, the resistance circuit breaker will be in open position when the main circuit breaker opens, and so that during'a reversal the resistance circuit will be closed at a time when the main circuit cycle; means for distributing the sparking impulses when produced in a similar cycle, the spark impulse producing means and distributor being so constructed that, upon a reversal of rotation of the engine, the. distributor cannot function at a time when sparking impulses are produced; and means operative upon reversal to weaken the sparking impulses, whereby the tendency of the distributor to function is greatly reduced.

19. In an ignition system for internal combustion engines, the combination with primary and secondary circuits; of a timing device including cooperating contacts in the primary circuit; a distributing device in the secondary circuit; an engine driven member having means for opening the contacts to.

induce sparking impulses in the secondary circuit 1n recurrent sequence having a certain relation to the engine cycle during normal operation but a different relation during a reversal of the engine; means connected with the engine driven member for causing during normal operation the distribution of impulses in said recurrent sequence, but inoperative to distribute sparking impulses when created upon reversal of the engine; and means controlled by the engine driven member for weakening the sparking impulsesupon a reversal, so that the tendency of the distributor to function is greatly reduced.

20. In an ignition system for internal conibusti'on engines, the combination with primary an? secondary circuits; of a timing device inc uding cooperating contacts in the primary circuit; adistributing device including stationary contacts and a rotor contactin the secondary circuit; anengine driven main her having means for opening the contacts in the primary circuit at times having a certain relation .to the engine cycle, during normal operation; means connected with the engine driven member for operating the rotor to distribute in a cycle similar to the timer cycle, the contact opening means operating upon a reversal of the engine in such a manner that a gap will exist between the rotor and any one 01: the stationary distributor contacts when the primary contacts are being opened; and means controlled by the engine driven member for weakening the sparking impulses caused by opening the primary contacts upon a reversal, so that the tendency of a sparking impulse to jump the aforesaid gap will be greatly reduced.

21. In an ignition system for internal combustion engines, the combination with primary and secondary circuits; of a timing device including cooperating contacts in the primary circuit; a distributing device including stationary contacts and a rotor contact in the secondary circuit; an engine driven member having means for opening the contacts in the primary circuit at times having a certain relation to the engine cycle, during normal operation; means connected with the engine driven member for operating the rotor to dis ribute in a cycle similar to the timer cycle, the contact openiug means operating upon a reversal to change the time relation of the timer cycle to the distributor cycle, the change beingso great that a gap will exist between the rotor and any one of the stationary distributor contacts when the primary contacts are being "opened; and means controlled by the engine driven member for weakening the sparking impulses caused by opening the primary contacts upon a reversal, so that the tendency of a sparking impulse to jump the aforesaid gap will be greatly reduced, the means for weakening the sparking impulses consisting of a resistance and cooperating contacts in series and connected in panallel with the first mentioned contacts in the primary circuit, the engine driven contact opening means operating upon a reversal to open the first mentioned contacts at a time'whe'n the second mentioned contacts are closed, and during the normal operation to open the first mentioned contacts when the second mentioned contacts are in open position.

22. 'In an ignition system for internal combustion engines, the combination with a condenser unit in a circuit; of a resistance unit in a circuit parallel with the condense:- circuit; means for periodically short circuiting both circuits; and means for periodically opening the resistance circuit,

23. in an ignition system for internal combustion engines, the combination with a con denser unit in circuit; of a resistance in a circuit pinnliel with the condense" circuit; means for periodiceliy short-circuiting both circuits; end menns for periodiceliy' 24. in en i nition stem for internet combustion engines, the combinntion with an inductive Winding; of on engine operated member; means controlled thereby and effective during normal engine rotetion for producing it relatively rapid change of megnetic flux in the region. of said winding; and devices, controlled by said engine 0 ernted member, and efiective during reverse of en- 20 gine rotntion to produce e re'letiveiy slow change of magnetic flux in the region of solo Winding.

25. In en ignition sys em for internal combustion engines the combination with e current source; of en ignition coil hnving pri mery end secondery Windin an engine driven member; means controlied thereby end effective during normal engine rotntion for producing e reietiveiy rapid reduction oi current in said primary Winding; end devices controlled by seid engine operated v rnernber; end efiective during reversel of engine rotation to produce it relatively slow reduction of current in said primory Wind- H19.

In testimony whereof I efiix H1 signature.

JGHNIL HUNT. Witnesses:

U. D. Mower.

. J. W. ltioDorrnnn.

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