US1400561A - mason - Google Patents

Description

C. T. MASON AND W. .l. HART.

IGNITION SYSTEM APPLICATION min oer-1e. 1917.

Patented 1m 20, 1921.

2 SHEETS-SHEET I INVHVTORS. 64M Z a Mam. By -mu/AMJH2gr a? J ATTO C. T. MASON AND W. I. HART.

IGNITION SYSTEM APPLICATION FILED OCT. I6, I917.

Patented Dec. 20, 1921.

2 SHEETSSHEET 2.

INVENTORS.

Chm TMA OM AND BY W/u/AM J. z

ATTORNEY the ang ,UNTITED STATES" PATENT OFFICE.

. CARL T. MASON, OF EAST ORANGE, NEW JERSEY, AND WILLIAM J'- HABT, O]? MOUNT- VERNON, NEW YORK, ASSIGNORS 'IO SPLI'IDOBF ELECTRICAL COMPANY, 01'

mm, NEW JERSEY.

IGNITION SYSTEM.

. Specification of Letterslatent. Patented Dec. 20, 1921.

Application filed. October 16, 1917. Serial No. 196,804.

To all whom it may cmwem:

Be it known that we, CARL T. MASON and WILLIAM J. HART, citizens of the United States, residing, respectively, at East 0range, in the county of Essex and Stateof New J erse county of York,'have invented certain new and useful Improvements in Ignition Systems, of which the following is a specification.

Qur invention relates to a means for firing the fuel charges in an internal combustion engine, particularly ofthe multi-cylinder'type. The system and mechanism which will be described herein relates'to the method of firing an eight cylinder V-type in. which Itwill be apparent from what follows that special arrangements must be provided for firing an engine of this character. In an eight cylinder engine of the four cycle type four ignition sparks are required for each revolution of the crank shaft or one spark for every 90 degrees of rotation of the said shaft. The ordmary two pole type of magneto delivers two sparks substantially symmetrical for each revolution of the armature or rotor; hence to get four sparks the magneto would have to be driven at twice crank shaft speed. It is at once seen that these sparks occur for every 90 degrees of rotation of the crank shaft and in order to use a magneto for firing multi-cylinder engines,

for example an eight cylinder one, it has been customary, in the past, to place the cy1-' inders at an angle of 90 degrees. It has been proposed in some cases to place these cylinders at an agle of 45 degrees when it becomes evident that to fire such an engine the sparks must be delivered at intervals of 45 and 135 degrees of crank shaft rotation. It is at once clear that the ordinary magneto or ignition systems can not be utilized for the purpose at hand.

We have solved the problem in a comparatively simple manner which renders the system but little more expensive than an ignition system used in connection with an engine having its cylinders placed at 90 deand Mount Vernon, in the estchester and State of New I between the cylinders is 45 degrees.

and secondary windings and a rotor operatmg 1n connect1on with the field structure which 18 capable of producing-four current impulses 1n the ignition coil for each rotation of the rotor, all of which will be pointed out more specifically hereinafter.

We utilize a cam 'on the rotor of such a. construction that it acts on the movable arm of the circuit breaker at intervals of 90 and 270 degrees of angular rotation of the magneto rotor. Since the rotor as above described 1s capable of producing four impulses per revolution it will be understood that the cam will act to suppress two of the current impulses which the rotor is capable of generating and will cause utilization of the other two at unequal intervals, that is 90 and 2170 degrees, of rotation of the rotor. By drlving the rotor at twice the speed of the engine crank shaft we produce the four sparks required asymmetrically spaced 90 and 270 degrees of angularity of the rotor but since this runs twice engine crank shaft speed the angularity referred thereto will be 4.5 and 135 degrees. We thus produce substantlally equal sparks but in asymmetri- CalIFGIIOdS of time.

- aving generated the sparks at the proper tension and at the proper time, these must be delivered to the various engine cylmders 1n the proper order. The distributer segments must therefore, be arranged in the same an ular order as the means for producing t e sparks, and in the form shown in the drawings accompanyin this specificatlon we have arranged the distributor segments in one plane so that the total number of sparks are delivered through the distributer, for one revolution of the distributer finger but since only four sparks are requlred for one revolution of the crank shaft the distributor fingermust be geared to run in synchronism with but at one half engine 'crank shaft speed or one quarter of the speed of the rotor of the magneto.

Qurinvention is particularly adapted for firing engines of the type described when used in connection with aircraft machines, but is just as adaptable for use on engines used on automobiles, boats or for other work. When used in connection with an aircraft engine, it is customary to provide an auxiliary means for starting these enines which are usually large and powerful. 11 starting aircraft engines it is usual to operated by hand-after the engine has been primed in the manner set forth above. The operation of this auxiliary or starting magneto provides a series of sparks which are delivered to the cylinders in an angular position a number of degrees later than the time of delivery of the main magneto, which is timed so the'spark has some advance or can be advanced for best running condi-- tions, so that the engine will start on compression in a forward direction. Since this starting feature forms no partof our present invention other than the method ofintroducingthe same in our tpresent type of distributer it will not be re erred to at any length in the following description.

In the drawings, Figure 1 illustrates a magneto suitable for the purpose, having a I portion broken-away to show the rotor.

Fig. 2 is a diagrammatical view of our ignitlon system.

of Fig Fig. 3 1s a plan view of our distributer, but having a portion broken away to show the distributer finger. Y 1

Fig. 4 is a sectional view on the line 4-4 Re erring now to the details, in which like numbers refer to corresponding parts in the variousviews, 1 illustrates a magneto of the Dixie type having a rotor with four lobes, 2, 3 and 4 of which are clearly seen.

The other lobe being directly behind 4 is' not visible. The field structure 5 carries a high tension coil6- having primary winding P and secondary winding S. On the end of the rotor and inclosed within the breaker box cover 7 is a circuit breaker shown on an enlarged scale and somewhat diagrammatically in Fig. 2. One end of the primary winding P is connected to an adjustable contact 8 which cooperates with the movable contact 9 on breaker arm 10 which is grounded at G. The condenser 11 is connected across the breaker points 8 and 9. A cam 12 is attached to the breaker end ofthe rotor and as shown in Fig.2 is about to open the contacts 8 and 9 at the point13. After the bumper 14 has passed over the point 13, the breaker arm closes the contacts 8 and 9 and when the point 15 reaches the bumper 14 the contacts -8 and 9 are again opened a eld until the point 16 is reached which is preferably about 180 degrees from the point 15, which in turn is 90 degrees from the point 13. The angular distance from 16 to 13 is made sufiicient to allow the magnetic flux time to build up through the core of the coil so that the distance from 15 to 16 may be more or less than 180 degrees but preferably more. While the cam 12 has been acting on the breaker arm 10 in .the manner described the rotor'has made one complete revolution and on account of the four lobes would have produced four magnetic impulses through the coil 6 had the primary circuit P not been held open in the manner described. We have found that the holding open of the primary for this period of time is'advantageous in that it gives the iron in the magnetic circuit an opportunity to rest, or recuperate, as it were, by removing the effects of the coil windin iron and even though the rotor 15 driven at twice engine crank shaft speed the two sparks delivered for one revolutionof the on the rotor will stay in at speeds of the rotor greatly in access of-that required. That is to say, the two, sparks delivered as above descrlbed will stay in at a much higher speed of the rotor than they would if the rotor were producing the four'sparks from the coil of which it is capable. ,'We have thus turned an apparent disadvanta e, that is, running the magneto at twice cran shaft speed, into a real advantage which will be speclfically claimed.

Inasmuch as the principles of o eration of the Dixie magneto have been escribed in numerous patents to Charles T. Mason, one

of which' is 1,226,233, issued May 15, 1917,

further description of the magneto does not appear to-be necessary to make this part of our invention clear to one skilled in the art.

. We will now describe our method of distributing the sparking current produced by the magneto. The secondary S of the coil 6 is adapted to be brought out of the insulating terminal 17 and is then connected to the binding post 18 on the distributer block 19. Mounted on the interior of the block 19, preferably molded therein, is an annular ring 20 to which the binding. post 18 is securely connected asshown in Fig. 4. 21 is a distributing fingerhaving a hub 22 pro jecting into a holder 23 to which the finger 21 is securely fastened in any suitable manner such as by cap 24 attached to the end of the holder 23. Fastened to the rim of the 'holder 23 by any suitable means such as bolts 25 is a gear wheel 26 which is adapted to mesh with another gear driven by some portion of the engine. Itwill be'understood that this gear ratio is such that the distributer finger is driven at one-fourth of the speed l iiobml holder 29 which abru sh 3 f adapted to be held in its workin position by spring 31." Directly below the rush holder- I29 1 and electrical? e connected thereto is a second brush hol part of thewl'lm" of the distributer J19 isa series of contacts -35to' 42 inclusivespaced so that the angle A- is22 degrees and the angle MB 67% degrees which isrespectively one half. -the. firing ,angularity of the engine crank shaft since the distributer finger rotates at one half crank shaft speed. Wires run from the terminals 35'to 42 inclusive to spark plugs 43 to 50 inclusive which are located in the cylinders according to the proper firing order. In thediagrammatical view shown in Fig. 2 no attempt is made to show the firing order of the engine. It" will be seen that the secondary or sparking current from the but inasynchronism or unequal intervals-of time. That is to sa ,two sparks travel from I the distributer 22% egrees apart followed by another at 67% degrees away succeeded by one 221; degrees and so on. It will also be seen that the sparks are all full strength although unequally spaced. Attention is called to this as in some types of magnetos used heretofore for production of sparks at unequal intervals more or less distortion of the magnetic material of the magneto has been necessary to getlthe proper spacing of the current waves which has resulted in many cases in sparks not being of equal value. Our method as herewith described obviates this difiiculty.

The starting magneto may be of struction having a primary winding secondary windlng s and circuit brea er 51 adapted to be acted on by cam 52. One end any conof the secondary is grounded in the usual manner and the other end is connected to I terminal 53 at the distributer block 19.

Finger 21 carries a brush holder 54 within which abrush 55 contacts with the inner end of terminal 53 being held in operative position by spring 56. Brush holder .54 has a contact rod 57 connected thereto and embedded in the insulating portion of the finger 21, preferably being molded therein. The outer end 58 of the rod 57 terminates in a point in close proximity to the contact terminals 35 to l 42 inclusive so that when the engine is in a to the plu the crank of the auxilia position to be started on compression the r--34 carrying a brush' 33 which is held in contact" with the annular ring 20 by spring 32. .Circumferentially mounted withinthe inner and Th'efthus produced'in the engine cylinder starts the engine forward and immediatelythe main magneto. icks-itup and further crankin not required. he startingsparkis shown of the ump-spark type but a 'wipe spark contact as used in the secondary of the main magneto m1ght be used, but we eliminate brush wear, etc., by using the jump spark in the starting eircuit. j ,Wh1le' wehave shown anddescribed one embodiment of our. invention it will be unof the auxi iary magneto is derstood by those skilled in the art, that nunerous changes and alterations may be made in the various details of the parts into the system. spirit of our invention and the scope of the ap ended claims. 4 y 3 avingthus described our invention what entering we claim is 2- 1. A distributer'block for use a an ignition system for eight cylinder 45 degree four cycle internal combustion engines, and with a generator ada ted to be driven at twice engine crank sha speed and having a source of magnetic flux, a generating coil, a rotatwithout departing from thev ing element adapted to direct the flux I through said coil incombination with means to produce two current impulses spaced 45 and 135 degrees apart when referred to said engine. crank shaft, said distributer block bemg adapted to. be attached to said engine and having terminals spaced 22} and 67-} degrees with means for connection to sparking devices in said engine c linders, adistributing finger inside said bloc geared to be driven by said engine at one hal crank shaft speed, an' annular ringin said distributer block with means for connecting a terminal of the generating coil thereto, a brush carried by said finger in running contact with said ring-and a second brush in electrical contact with the first for contacting with said block terminals as the finger rotates, a terminal on said block adapted to be connected to an auxiliary generator, a third brush associated with the distributing finger in running contact with the last mentioned terminal, a distributing contact connected to said third brush and ada ted to conduct sparking current to said 'stributer block terminals when said auxiliary generator is operated in the manner de- 2. A distributer block for use in an ignition system for eight cylinder 45 degree four cycle internal combustion engines, and with a generator adapted to be driven at twice engine crank shaft speed and having a source I mg adapted to be attached to saidengine and having terminals spaced 22% and 674 degrees with means for connection to sparking devices erating coil thereto, a brush carried by said finger in running contact with said ring and a Second brush carried in the end of said finger substantially at r ght angles to the first and electrically connected thereto for contacting with said block terminals as the finger rotates, a terminal on said block adapted to be connected to an auxiliary generator, a third brush associated with the distributing-finger in running contact with the last mentioned terminal, a distributing contact connected to said third brush and adapted to conduct sparking current to said distributer block terminals when said auxiliary gen erator is operated in the manner described.

In witness whereof we afiix our signatures.

. "CARL-T. MASON.

WILLIAM J. HART.

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