July 13, 1948- I R. L. SEXTON 2,445,245 ‘ ENGINE IGNITION AND POWER TESTING APPARATUS Filed Aprii 16, 1945 . 2 Sheets-‘Sheet 1

ATTORNEY July 13, 1943- I R. L. SEXTON . . 2,445,245 ENGINE IGNITION AND POWER TESTING APPARATUS

Filed April 16, 1945 _ ‘ ' 2 Sheets-Sheet 2

129.2; I‘ - 12:9, 3.

Poss/2Tv - INYENTOR L. $Ex7'0/v Patented July 13, 1948 2,445,245

. UNITED STATES PATENT } OFFICE

ENGINE IGNITIOJZZJZQWER TESTING ’ L ‘I APPARATUS ‘_ Robert L. Sexton, Flushing, N. Y. Application Aprilv 1.6, 1945, Serial No- 588,565 3 Claims. (013137-116) 1 , 2 This invention. relates generally to. internal, determine whether or not the ignition in that combustion engine testing apparatus, and the is faulty. In the event of dual ignition, the. pressure. of two biflttonsv will determine invention has. reference “more particularly to. a whether or not the ignition of the cylinder is novel aircrait engine ignition and cylinder power 5. iaulty, whereupon the. ‘pressing of the'two‘buté testing apparatus. ' tons alternately will determine which Plug. in it is extremely imnorta in: modern internal ‘ combustion engines and especially aircraft such cylinder is faulty, so that an, airplane op engines, that the same he kept operating e?i— erator is. able to note. even while ini?iehtjjwhich ciently andv with: as short shutdowns for repairs. oi the thirty-six plugs in an eighteenkcylimler as‘ possible. > Theinyestrnent in; modern large air 10 engine is .taulty by merely pressing. ‘buttons; planes. is so sreetthst it is necessary to keep the thereby enabling. the replacement of a. Single (1*? planes- in the. air aenrol;.iiiietelyv seventy per cent festive. plus without replacing eighteen Plugs of the time in ordervto- recoup the investment A. further feature of the present invention is made in the airplane, and hence it, becomesvery to provide. test equipment. tor checking on the 15 torque and power output of any desired cylinder important that engine overhaul periods b of an engine, for example, if it happens to be an. shortened as much as possible > eighteen-cylinder engine, the engine Operator ' When it is realizedthat ignition troubles are the cause of more engine failures than any other may select any cylinder and determine its torque factor, the importance of easily detecting and and power output- In that way he readily deter: locating ignition troubles. becomes very-apparent 20 mines Whether a cylinder is. performing properly, The. present methods of- shoqting. ‘ignition trouble and thereby foretell failures. . i . are arduous andconsumeconsiderable’time. For Very often a cylinder will gradually fall off example; assuming an eiehteenrcylimier aircraft in power, and. this maybe true OI a number of engine is. "rough on the left magneto,” which .cylinders, so that the Overall. power of the engine would tend to. indicate that a rear plug is fouled, 25 falls 0.1‘! and yetthe. trouble is not sufficiently had‘ in that case,- under the present system of testing, to Warrant complete overhaul of the engine. By eighteen 'spark- plugs are usually ehanged, where using. the test equipment of the presentinyene actually onlyoue plug, is at fault. ‘This makes tion,v any cylinder or cylinders falling Off in power ignition repair work on airplane eneinesnot only can be quickly detected and correction made. a. lengthy matter. but also eignensive. Further 30 Furthermore, detonation resulting in. loss of more,.eyl1nders veryoiten fall: off in powerz and power can be detected and. located. upto thev time citrus-invention» it was impossible . A further feature of. the present invention is to‘ determine readily J'llst which cylinder was to provide a small, inexpensive, compact‘, and falling off inpower and to what extent. Further light test equipment that is readily anplled i0 more, faulty ignition results; in. local, radio inter. 35 existing engine installations, and is easily op: ference; which is highly objectionable. especially erated for testing. and locating. ignition troubles andv defective cylinders, even while the engine is intaircraft. ’ I I g . The applicant. hereof‘ has‘ disoovered means running, thereby greatly decreasing the maintee whereby the ignition. of any one selected cylinder nance time heretofore required in servicingaire maybe ‘isolated; so‘ to speak, even. while the 40 planes and cutting; the ‘cost of maintenance engine is running, and tested for faulty action. enormously In the event of suchfaulty action, it known \ “Other features and advantages will hecomeapg de?nitely just where the trouble lies, so thatgcare= patient from the speci?cation, taken in connece fulv and tediousexamination of? all spark 'plugs tion with‘ the accompanying drawings wherein in all cylinders is unnecessary. - . ' . i 45 the invention is embodied in concrete form. important feature of the present invention In'the drawings, I ,_ is: to Provide novel engine ignition and: Power Fig. 1 is a schematic view of the-novel engine testing apparatus which enables the cosine 0P" ignition‘apparatus of this invention shown, as stator to 591st‘; any cylinder in‘ which? he is applied. to a four-cylinder engine; ill'??l’??tlid infill by merelwressing 9.1. huttqll 5° llis- 41A. is a diagrammatic view showinstlis 2,445,245 3 4 apparatus of the present invention applied to a Fig. 3) corresponding to the number of cylinders dual-ignition nine-cylinder aircraft engine; shown in the structure of Fig. 1, wherein a four Fig. 2 is a fragmentary sectional view of a por cylinder engine is involved, which numerals cor tion of the apparatus; respond to and are arranged in the ?ring order of Fig. 3 is an end View of the structure shown in the engine cylinders. The open mouth of this Fig.2; and bell housing ?ts into a circular depression 31 pro Fig. 4 is an elevational view of a part of the vided in a plate 38 attached to the end of the structure of Fig. 2 as taken substantially along magneto housing 39. The bell housing has a the lines 4-4 of Fig. 2. radial lip or ?ange 40 that is engaged by spring Similar characters of reference are used in all 10 pressed washers 4| carried by screws 42, which of the above ?gures to indicate corresponding serve to retain the open mouth portion of the bell parts. housing in assembled relation with the plate 38 Referring now to the drawings, the reference and rotatable with respect to this plate. An in \numeral 5 designates a contact breaker of dex member or pointer-"43 is carried by the plate the engine magneto which, as shown in Fig. 1A, 15 38 for cooperating with the marks I, 2, 3, and 4 may be magneto 6 or 1. The cam 5 is adapted . : on the periphery of the bell housing 24. Obvi to actuate the breaker arm 8 for opening and , ously, if the engine had eighteen cylinders, there closing the contact breaker points 9 located in the . . ' would be eighteen'numbers on the bell housing circuit of the primary winding I0 of the magneto. 24. As is customary, when the primary contact points 20 I '1 An outer end cover or knob 44 is ?xedly mount 9 open, the flow of primary current through coil , ed ,upon the bell housing 24 and has a knurled I 0 is interrupted, causing an' extremely rapid “ “outer surface 45 which may be grasped for turn change in ?ux linkages, resulting in the produc - ing ,this, bell housing so that any particular cyl tion of a high voltage in the secondary winding inder number, such as I, may be aligned with the II of the magneto, which voltage is supplied 25 pointer 43 as shown in Fig. 3. With such position through lead I2 to the ?nger I3 for of the bell housing, the cam follower 29 is so posi passage through distributor contacts I, 2, 3, and tioned angularly with ,respect to the contact 4 and connected I4, I5, I6, and breaker cam 5 and cam groove 28 of the auxiliary I‘! to engine spark plugs I’, 2', 3', and 4'. So far cam that when cylinder I of the engine ?res, the the structure is typical of an engine ignition 80 cam follower 29 will drop into cam slot 28, there system. . _ . by closing contact points 30 at the very moment In its preferred form, the apparatus of the that the in cylinder I ?res. However, present invention is an attachment comprising this action ‘has no‘ effect so long 'as the push-but an auxiliary cam shaft I8 having an enlarged ton 34 is open. If push-button 34 is held closed, hollow inner end portion I9 which ?ts Within a 35 thenevery time cylinder I is about to ?re both recess provided in the outer end of the magneto sides'of the primary winding II] will be grounded breaker cam 5 (see Fig. 2), the said auxiliary because (referring particularly to Fig. 1) with shaft I8 having a driving block or key 29 adapted the contact points 39 closed and switch 34 closed, to ?t into a slot provided in the end of the con the lower side of the ‘primary winding I0, as tact breaker cam 5, whereby this breaker cam shown in Fig. '1, is grounded and its other side is drives the auxiliary cam shaft I8. ' ‘ always grounded, and so no voltage is induced in Shaft I8 is mounted on a rotor-bearing block the secondary'II and consequently the plug or 22 which abuts the enlarged end portion I9. cylinder‘ I Will receive no secondary current and Bearing block 22 'is longitudinally slidable 'in hence will not'?re. I slide-bearing aperture 23 provided in a bell hous 45 _ Likewise, if the knob 44 is turned so as to bring ing 24. _A screw 25 extends through housing 24 the number 2' on bell housing 24 opposite pointer andprojects into a longitudinal groove 26 in rotor 43, then each time that cylinder number 2 ?res, bearing 22, thereby serving to prevent the turn the contact points 30 will be closed, and if the ing of this bearing while permitting longitudinal push-button 34 is also closed at that time, the movement thereof. A coil compression spring 21 50 plug or cylinder number 2 will not ?re since both presses on the rotor-bearing‘block 22 and hence sides of the primary winding II] are shorted. urges the enlarged end portion IQ of shaft I8 ' When applying the device to a dual-ignition inwardly toward and into engagement continu engine as shown in Fig.v 1A, two sets of contact ously with the contact breaker cam 5 to be driven points 30 and 30’ are employed and likewise two by the latter. ’ - 55 push-buttons 34 and 34’ are employed, leads '35 The enlarged portion I 90f auxiliary cam shaft and 35' connecting to the primary winding of the I8 is provided with a peripherallongitudinal cam two magnetos I5’ and ‘I. Only two high tension groove or depression 28 (see especially Fig. 4) leads of these two inagnetos are shown in Fig. 1A which cooperates with a cam‘ follower 29 that connected to a single cylinder, but it will be un serves to actuate a pair of breaker points 30. So derstood that leads are connected to each of the long as the follower 29 is riding on the high sur cylinders. A switch 46 is shown for permanently face 28' of the cam shaft portion I9, the follower grounding the primary ll] of the magneto when 29 holds the breaker points 30 disengaged by desired. In Fig. 1A, thev auxiliary cam shaft I8 ?exing arm 3| upwardly. However, when the is shown driven directly from the engine through cam groove 28 rides under the follower 29, this 65 reduction gearing 56 instead of from the mag follower drops down into groove 28 and allows the neto. ' ‘ resilient arm 3I to move downwardly, thereby en A torque meter is attached to the engine to gaging points or contacts 30 as shown in Fig. 4. indicate the brake means effective pressure These breaker points are connected at one side (B. M. E. P.) or the pressurecomponent of torque (see Fig. 1) through a lead 32, condenser 33, 70 in pounds per square inch. This torque meteris push-button 34, and lead 35 to one side of the illustrated as comprising a sun gear 48, which is primary winding III’. The other side of the break attached by linkage 49 to a plunger 50 working er points 39 are connected by lead 36 to vground. within hydraulic cylinder 5I which is supplied The bell housing 24 is shown on its exterior with oil under pressure by pump 52, and a pres surface provided with numerals I, 2, 3 and 4 (see sure gauge 53, which may read directly in torque $441554 6'1 ' unlts;jif-‘ desired, is connected to-the cylinder?il. plugfohly; by closing switch/‘341 alone;- ' ‘If _ now: A‘ pinion; 54’meshes with the sungear~4l1and¥with the-B; EI'P. does‘fall'ofl', the rear plug'has: the-propeller drive, 'gear- 55 so that the torque faultyignition, andif the B. E; Phdoesrnot'i applied 7to the ‘propeller isv transmitted". through. fall, the rear plug and ignition is all v‘right. The pinion ‘54 and gear~4?~ to plunger 50, whereby - pushhbuttond? is nowclo‘sed; thereby‘grounding meter 53 reads the. torque ofthe. engine or may the rearrplllg, and-thesame procedure iisirep'eated; be calibrated in pressure units, if'de'sired, thereby ‘determining whether the front ‘plug is: From the readingof meter 53,- the brake horse flringiproperlyw Thus’, it is readilypossi'ble tode~ power of the engine can be readilyscalculatedas termine which cylinder is‘ not‘ functioning prop erly, and-ii it is' dual ignition - it‘ is' readily‘ deter; follows: minablei as-to which of the two-ignition ‘systems is“ atf fault" as‘well » as the particular‘ plug‘ which! is - B. H. PM 33,000 ’ wherein T represents the torque. In operation, ‘ In making power’ tests, the engineer will press to determine whether or not the spark plug of a 15 both buttons 34 and 34' simultaneously and note cylinder is functioning properly, it is merely the B. M. E. P. drop, thereby determining the necessary to turn the knob 44 until the desired power output of any particular cylinder by the cylinder number, such as number I, is opposite change in B. M. E. P. reading. By pushing the the index 43 as shown in Figs. 1 and 3. The brake button 34, controlling the front plug, we can test mean effective pressure (B. M. E. P.) is read from 20 the rear plug ignition, and by pushing the vbutton the torque meter 53. The push-button 34 shown 34', controlling the rear plug, we can test the in Fig. 1 is then depressed so as to ground both front plug ignition. sides of the primary l0, thereby shutting off the The apparatus of this invention also serves for high tension power to the plug of cylinder l. The determining the location of faulty ignition caus B. M. E. P. reading of meter 53 is again noted 25 ing radio interference. Where a dual-ignition during the ignition cutout of cylinder l. The system is employed, each magneto is grounded in difference between the ?rst B. M. E. P. reading turn by closing switches 46 and 46' in succession. and the second represents the loss in torque, By grounding switch 46, if the interference ends, which can be converted to horsepower as follows: it is known that the ignition trouble is in the 30 system associated with switch 46. If the trouble lost B. M. EIPXR. P. M.=B' H_ R1051; still persists, then it is the asso ciated with switch 46’. Each plug of the faulty wherein ignition system is then grounded in turn to de l termine which plug is faulty. The connections R 35 to this plug are then checked as well as the plug to detect loose connections. Thus, it will be seen represents the engine factor which does not that merely by pressing buttons 34 and 34' the change. engineer can quickly determine which cylinder For a good cylinder the value of B, H. P. Lost of a multi-cylinder engine is not functioning should equal 40 properly and then readily locate the plug of that 13. H. P. particular portion of the ignition system which K is at fault, thereby enabling the replacement of one plug instead of many plugs and eliminating where K equals the number of cylinders of the the hunt and try methods at present employed. engine. If there is no falling off of the indicated B. M. E. P. when closing the push-button 34, the Since many changes could be made in the above particular cylinder being tested is not putting construction and many apparently widely differ ent embodiments Of this invention could be made out power. If the cylinder is operating properly without departing from the scope thereof, it is there should be a drop in B. M. E. P. which is intended that all matter contained in the above equal to the original B, M. E. P. reading divided description or shown in the accompanying draw by the number of cylinders in the engine. Thus, ings shall be interpreted as illustrative and not this testing device is very rapid in its action and cylinders can be tested as rapidly as the engineer in a limiting sense. What is claimed is: can turn the knob 44 to successive cylinder num 1, Engine and ignition power testing apparatus "bers and press the button 34 and read the meter r comprising an auxiliary cam driven from the en 53. gine, contact points actuated by said auxiliary Where dual ignition is used, as shown in Fig. cam, a housing for carrying said contact points, 1A, to locate the cylinders having faulty ignition, said housing being angularly adjustable with re both buttons 34 and 34’ are pressed or closed spect to said auxiliary cam to thereby effect the simultaneously, thereby grounding the corre closing of said contact points simultaneously with sponding plugs of cylinder l, for example, simul 60 the ?ring of any selected engine cylinder, a cir taneously, whereupon the fall in B. M. E. P. is cuit connecting the engine ignition through said noted. If no fall is indicated, obviously no power contact points to ground, switch means in said is being received from that cylinder, which indi circuit for closing said circuit to cut off the igni cates any one or more of the following difficul 65 tion of such selected cylinder, and a torque indi ties: cator operable from the engine, for showing a. Poor compression, changes in the torque output of the engine re b. Both spark plugs fouled simultaneously (very sponsive to the operation of said switch means. rare), 2. In apparatus of the character described for testing of engine cylinders, contact means con 0. Mixture not reaching cylinder, 70 d. ‘Spark plug wires broken or not hooked to nected at one side with the engine ignition and at plugs. the other side with ground, adjustable means for Assuming that the B. M. E. P. does fall to some setting said contact means for operation in syn extent when both plugs are grounded, the next chronism with the ?ring of any selected engine step is to ground one plug, for example, the front 75 cylinder, whereby the ignition of such cylinder is 8 cut out when desired, and a torque meter attached, switch means serves to shut off the current to the to the engine for indicating change in engine‘ spark plug selected, and a torque meter driven torque with the cutting out of the ignition of such. from the'engine for indicating change'in engine selected cylinder. > ' - torque upon the closing of said switch means. -3. Apparatus for shutting off the supply of high ROBERT L. SEXTON. tension current‘to engine spark plugs during en gine operation comprising a grounding circuit ‘ REFERENCES CITED electrically connected with the spark plugs,-sai'd' circuit comprising make and break contact mem The following references are of record in the bers actuated from the engine and switch means m ?le of this patent: for completing said circuit, means for adjustingv FOREIGN PATENTS said contact members for causing actuation ,of the Number Country Date same in synchronism with the ?ring of any se lected spark plug, whereby the closing of said 139,829 Great Britain ______Mar. 18, 1920,