US1360274A - de lorme - Google Patents

Description

A. C. DE LORME.

IGNITION SYSTEM.

APPLICATION FILED APR. 15, 1919.

Patented Nov. 30, 1920.

2 SHEETSSHEET l- INVE/VTUR HLFIKED C. DE LUKML.

' A TTORNE A. C. DE LORME.

IGNITION SYSTEM,

APPLICATION FILED APR. 15, 1919.

1 3 0 274 Patented Nov. 30, 1920.

2 SHEETS SHEET 2.

} INVENTOR HEFI'KED ED: LU ML BY awe-waif ATTORNEY 30 cycle type four ignition sparks are required UNITED stares ALFRED C. DE

TENT QEHQE.

a2. is i LORME, OF EAST ORANGE, NEW' JER$EY, ASSIGNOR TO SPLITDORF ELECTRICAL COMPANY, OF NEW'ARK, NEVT JERSEY.

IGNITION SYSTEM.

Application filed April 15,

To all whom it may concern:

Be it known that I, ALFRED C. DE LonMn, a citizen of the United States, residing at East Orange, in the county of Essex and State of New Jersey, have invented certain new and useful improvements in Ignition Systems, of which the following is a specification.

My invention relates to the method of firing the fuel charges in an internal combustion engine, particularly of the multi-cylin' der type. The system which will be described herein relates to the method of firing an eight cylinder V-engine in which the angle between the cylinders is degrees.

An application filed by Carl T. Mason and William J. Hart, on October 16, 1917, Serial No. 196,804, describes the special arrangements which must be adopted to fire an engine of this character and sets forth means for accomplishing the result. My invention is directed to improvements of certain details of the abovementioned application and hence much of the descriptive matter thereof will be found in this application in order to make the same clearly understood, but no claim is made for the broad invention set forth in the above mentioned application.

In an eight cylinder engine of the four for each revolution of the crank shaft or one spark for every 90 degrees of rotation grees.

of the said shaft. The ordinary 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 to fire multi-cylinder engines, for example an eight cylinder one, it has been customary, in the past, to place the cylinders at an angle of 90 de- Where the cylinders are placed at an angle of 15 degrees it becomes evident thatthe sparks must be delivered at intervals of 15 and 135 degrees of crank shaft rotation and it is at once seen that the ordinary magneto or ignition system cannot be utilized. In the said Mason-Hart application the problem was solved in a unique manner by using a magneto of the Dixie type, as set forth in Patent 1,226,233, issued Specification of Letters Patent.

Patented Nov. 36 1920.

1919. Serial No. 290,332.

May 15, 1917, to Charles T. Mason, wherein there is'an adjustable field structure carr ing the high tension coil having the usual primary and secondary windings and a rotor operating in connection with the field structure which is capable of producing four current impulses in the ignition coil for each rotation of the rotor, all of which will be hereinafter referred to, and by utilizing 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 is capable of producing four impulses per revolution it will be seen that the cam will act to suppress two of the current impulses which the rotor is capable of generating and utilines the other two at unequal intervals, that is, 90 and 270 degrees of rotation of the rotor. By driving the rotor at twice the speed of the engine crank shaft the necessary four sparks are produced but 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 45 and 135 degrees. Hence substantially symmetrical sparks are produced but in asymmetrical periods of time.

After the sparks are generated, as above described, they must be delivered to the various engine cylinders in the proper order. In the said lllason-Hart application the con tact segments in the distributer block are arranged in such angular order that two sparks follow each other at intervals of 22:}; degrees of rotation of the distributing finger followed by an interval of 67% degrees, the contacts in the block being spaced according to these angles from which it is seen that the distributer block must be made relatively large in order to give suflicient space between the two contacts that are 22!;

degrees apart so that the distributer brush 100 carried by the distributer finger will not leave a track between the said two contacts suflicie'nt to cause the spark to jump from one to the other.

My invention is directed more particu- 105 son-Hart application. In addition to the 110 distributing means for the service magneto, I have shown a source of starting ignition current which is required for starting large engines on compression as set forth in the said Mason-Hart application and which will not be described at length herein.

In my application Serial No. 199,134. filed October 29, 1917, I have shown a distributing device consisting of a block carrying contacts that are equally spaced apart and a double ended distributing finger for distributing the sparking current to the con tacts in such a manner as to fulfil. the firing conditions of the engines. In a companion application, Serial No. 199,135, filed Octoher 29, 1917, I have shown and described another distributing device for the purpose at hand. In the said Mason-Hart application and my two co-pending applications above referred to it is almost necessary that the distributing device consist of the block and rotating finger or its equivalent be placed on the engine otherwise the magneto must be built considerably out of proportion in order to accommodate such a large distributer block.

The invention covered by this application which is a division of my co-pending application, Serial No. 199,136, filed October 29, 1917, is directed to the designing of a distributing device which may be mountedon the magneto without materially increasing the size of the distributer block over that used in ordinary work involving the use of the same number of engine cylinders.

By having the distributing block and finger part of the magneto itself the work of assembling and testing the ignitlon clrcuits is very much simplified although it is to be understood that the block and rotating finger may be placed on the engine separate from the magneto.

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

Fig. 2 is a diagrammatic View of my ignition system.

Fig. 3 shows an alternative form of distributer block and rotating finger.

Referring now to the details, in which like numbers refer to corresponding parts in the various views, 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 1 is not visible. Field structure 5 carries a high tension coil 6 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 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 the 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 of the rotor and'as shown in Fig. 2 is about to open the contacts 8 and 9 at the point-13. After the bumper 14 has passed over the point 13, the breaker arm closes the contacts 8 and 9 and when the point 15 is reached by bumper 14: the contacts 8 and 9 are again opened and held open until the point 16 is reached, which is preferably about 180 degrees from the point 15, which in turn is approximately 90 degrees from the point 13. The angular distance from 16 to 13 is made sufficient 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 made more or less than 180 degrees but preferably more. Vhile 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. It has been 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 windings on the iron and even though the rotor is driven at twice engine crank shaft speed the two sparks delivered for one revolution of 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 described will stay in at a much higher speed of the rotor than they would if the rotor were producing four sparks from the coil of which it is capable. Hence an apparent disadvantage, that is, running the magneto at twice crank shaft speed, has been turned into a real advantage.

Inasmuch as the principles of operation of the Dixie magneto have been described in numerous patents to Charles T. Mason, one of which is 1,226,233, issued May 15, 1917, which also shows a method of bringing out the outer end of the high tension winding of the ignition coil to the rotating member of the distributer, further description of the magneto does not appear necessary to make my invention clear to one skilled in the art.

Referring to Fig. 2, 19 is a part section in perspective of distributer block 18. Mount ed on the interior of the block 19, preferably molded therein, are two rows of contacts arranged four in each row. In the section 19 but two of the contacts 2022 and 2123 in each row are shown. The distributing member or rotating finger 24 carries two distributer brushes 25 and 26 which are electrically connected together and by means of a suitable connector passing through the stem 17 they are connected with the high tension winding S of the coil 6. The brushes 25 and 26 are set intwo different adjacent tributer finger 2 1 also carries two sparking points 27 and 28 whichare electrically connected together'and to contact 29 in the end of the distributing member 24. In distributer'block 18 a terminal 30' is adapted to receive a wire coming from the secondary s of the starting magneto which has a primary P and breaker arm 31 and cam 32. In Fig. 2 the brush connection between termi- 'nal 30 and contact 29 is not shown for thesake of simplicity in drawing. The brushes 27 and 28 are set in retarded position with respect to brushes 25 and 26.

, In the operation of the service magneto as the distributing finger 24 rotates in the direction of the arrow brush 25 engages con,- tact 20 which is connected to the proper spark plug. Since the next spark required must cover 22.; degrees of rotation of the distributing finger it will be seen that this condition is met when brush 26 engages the contact 21 at which time the brush 25 has moved forward 22;}- degrees ahead of contact 20 which is 67% degrees from contact 22, the

same being 90 degrees from contact 20.

Therefore, the next current impulse from the generator is delivered by brush 25 to contact 22 and thence to the proper spark plug and so on for a complete rotation of the distributing finger 2&, it being understood that this is geared to rotate atone half engine crank shaft speed.

The starting magneto may be of any construction or a battery and coil may be used instead. The connection to the starting contacts 27 and 28 being as previously described. The contacts 27 and 28 it being understood are placed with reference to brushes 25 and 26 so that they are opposite the proper distributer block contact for starting the engine on compression by operation of the auxiliary or starting magt neto or its equivalent. The starting spark contacts are shown of the jump-type but wipe spark brushes the same as 25 and 26 may be used but where the starting contacts are used only occasionally and for short intervals of time" the jump-spark eliminates brush wear.

Instead of having the contacts in the dis tributer block symmetrically arranged 90 degrees apart in two rows and staggering the brushes in the rotating finger the proper amount, I may reverse the procedure and arrange the contacts in one row in a distributer block so that they are displaced 221 degrees from the contacts in the other row, in which case the service brushes on the dis- It is apparent that the position of the grooveand ridge may be reversed. Various other modifications may be made in the numerous details, all of which will be understood by those skilled in the art, without departing from the spirit of my invention or the scope of the appended claims.

itiaving thus described my invention what I claim is i 1. In an ignition system for eight cylinder 45 degree four cycle internal combustion engines, a generator adapted to be driven at twice engine crank shaft speed and having a source of magnetic flux, a generating coil, a rotating clement adapted to direct the flux through said coil in com bination with means to produce two current impulses spaced 45 and 135 degrees apart when referred to said engine crank shaft, a distributing device consisting of a block having terminals spaced 90 degrees apart in two rows with means for connection to sparking devices in said engine cylinders, the contacts in one row being displaced 221- degrees from the contacts in the other row, a distributer finger in said block geared to be driven at one half crank shaft speed and having a pair of brushes adjacent to each other but in different planes to correspond to the two rows of terminals, and in electrical connection with the coil whereby said current impulses are conveyed to said block terminals at intervals of 2235 and 67} degrees of rotation of the finger as and for the purpose described.

2. In an ignition system for eight cylinder 45 degree four cycle internal combustion engines, a generator adapted to be driven at twice engine crank shaft speed and having a source of magnetic flux, a gen erating coil, a rotating element adapted to direct the fluX through said coil in combination with means to produce two current impulses spaced i5 and 135 degrees apart when referred to said engine crank shaft, a distributer block having terminals equally spaced 90 degrees apart in two rows which are displaced as to each other 223; degrees with means for connection to sparking devices in said engine cylinders, a distributing finger carrying a pair of brushes in adjacent planes corresponding to said rows of block terminals inside said block geared to be driven at one half engine crank shaft speed, with means for connecting a terminal of the generating coil to said brushes, said brushes being adapted to contact with said block terminals first in one row then in the other successively according to the firing order of the engine, an auxiliary ignition generator. a terminal on said block adapted to be connected to said generator, a brush associated with the distributing finger in running contact with the last mentioned terminal, a pair of contacts displaced one behind each of the main brushes and connected to the brush associated with the distributer finger and adapted to conduct sparking current to said distributer block terminals when said auxiliary enerator is operated in the manner described.

3. The combination with an eight cylinder 45 degree four cycle internal combustion engine and a sparking device constructed to deliver four current impulses when driven at twice engine crank shaft speed, of a distributing mechanism comprising a rotating finger geared to rotate at one fourth of the speed of the rotating element of the sparking device and a distributer block having eight contacts arranged around the periphery of said block in two rows of four each at equal angular intervals of 90 degrees but the contacts in one row being displaced 229; degrees from those in the other row, said distributor finger carrying two brushes in line in adjacent planes corresponding to said rows of contacts with means for conveying the sparking current impulses to said brushes whereby when said finger is rotated the current impulses are conveyed to the said contacts alternately and successively in the two rows as and for the purpose described.

In witness whereof I aflix my signature.

ALFRED C. DE LORME.

Images