US1859308A - Engine ignition timeb - Google Patents

Description

y 1932. M. MALLORY 1,859,308

ENGINE IGNITION TIMER Filed Jan. 8, 1927 2 Sheets-Sheet 1 May 24, 1932.

M. MALLORY 1,859,308

ENGINE IGNITION TIMER Filed Jan. 8, 1.927

2 Sheets-Sheet 2 Patented May 24, 1932 UNITED STATES mm: mnnoar, or ronmao, omo

ENGINE IGNITION TIMER Application filed January 8, 1927. Seriaiflo. 159,789.

My invention has for its object to rovide an ignition device for internal com ustion engines that will produce hot arks that endurefor a considerable perio in the spark plugs of the engine and insure ignition at all engine speeds. 7

As is well known induction coils have characteristic time constants in which the maximum number of lines of force are produced 10 by the primer coil with a given current intensity, and i the circuit breaker of the ignit1on system 0 ens the primary circuit to produce sparks before the expiration of the time required for complete building up of the lines of force there is a corresponding reduction of the secondary current and the corresponding reduction in the effectiveness of the sparks. As a result either no sparks may be produced when the primary circuit is broken, or, if produced, the sparks have no heat value and will not ignite the gaseous fuel in the cylinders of the engine.

When, therefore, the engine and, consequently, the timer of'the ignition system is I speeded up, the periods of flow of the primary current is reduced by reason of the increased speed and also by reason that the controlling cams at an increased speed knock the circuit closers away from the circuit closers of the cams and the fixed'contacts of the circuit closers so as to delay the return of the circuit closers to its fixed contact which results in the reduction of the time in which the lines of force of the induction device may be built and consequently results in poor ignition. When, however, the coils are designed to produce short time constants, the battery losses are correspondingly large, since the periods allowed for the primary current to rise to its full value in advance of each spark must necessarily come within the period of each cycle of the engine. Where two coils are used there is invariably a want of synchronism or variation in spark intensity in the ignition of the cylinders of the engine. Economy of time wherein the ignition system may function is absolutely imperative. This is particularly true when eight or twelve cylinders are to be ignited from current transformed from the battery current through a single induction coil.

By my invention high tension sparks of substantially uniform heat value are produced when the engine is running at high and low speeds, and at the same time battery losses are prevented when the engine is running at low speed. A pair of circuit closers are located in the systems involving the use of my invention which will cooperate to extendthe period of closure of the primary circuit as measured 0 in the angle of rotation of the crank shaft when the speed of the engine has increased sufliciently to make such increase desirable. The period of closure as measured in the angle of rotation of the en ine shaft may be ad- 5 justably extended by s ifting one circuit closer relative to the other and the spark may be automatically advanced as desired by shifting both circuit closers relative to a rotative cam that operates to open the'circuitclosers. 7c The circuit closers are connected in parallel in the primary circuit and the circuit may be completed through either or both of the circuit closers. When the speed reaches substantiall the point of limitation of the efii-. ciency o the induction coil when controlled by a single circuit closer the second circuit closer is shifted automatically relative to the controlling cam to extend the eriod of closure of the circuit, as measure in the angle so of rotation of the engine shaft or to mamtain the length of the time of closure substantiall constant or at least of a length to permit t e i 'tion system to fully function and produce ot ignitable sparks.

The invention also eliminates the use of pointed co-acting controlling surfaces on either the cam or the circuit closer, "or on both, and utilizes surfaces, one on the cam and the other on the circuit closer, for producing a relatively gradual movement of the circuit closer as distinct from a sharp, quick movement. This prevents knocking the circuit closer from the surface of the cam and enables the circuit closer to move in accordance with the surface of the cam, notwithstanding the speed of rotation of the cam.

The invention may be used in conjunction with ignition systems of different forms and to illustrate a practical application of the invention I have selected an ignition device containing the invention as an example of such systems and shall describe it hereinafter. The system selected for purposes of illustration is shown in the accompanying drawings.

Fig. lillustrates a vertical section through the timer and shows a circuit closer cam controlling member in one position. Fig. 2 is a side view of a part of the timer shown in Fig. 1 and illustrates a second position of the circuit closer cam controlling member. Fig. 3 is a view of a section taken on the plane of the line 3-3 indicated in Fig. 1 and shows the cam operated circuit closers in one position relative to the cam. Fig. 4; illustrates a similar view showing the circuit closers in another position relative to the cam. Fig. 5 illustrates an end view of the circuit closers when a cam controlling member is located in one position and shows one side of the cam controlling member. Fig. 6 illustrates a view similar to that of Fig. 5 showing the said cam controlling member in another position. Fig. 7 illustrates another part of the cam controlling member and shows the position of the circuit closers when the other side of the cam member is in one position. Fig. 8 is similar to that of Fig. 7 and shows the position of the circuit closer when the said part of the controlling cam is ,in another position. Fig. 9 illustrates a perspective view of the clrcuit closer cam controlling member. Fig. 10 1s a diagram of the ignition system that may be used in connection with my invention.

In the form of construction shown in the figures-the-ignition timer is provided with a shell 1 having a plurality of sections 2,3 and 4 that may be secured together by spring clips 5, a spindle 7 of the type commonly used in such timers, is provided with suitable bearlugs and is rotated by suitable mechanism through which it is connected to the crank shaft of the engine and so as to rotate in the desired speed ratio to that of the crank shaft of the en 'ne.

A suita 1e governormember 10-is supported on'the spindle 7 and so as to be actuated according to the speed of the spindle. In the form of construction shown the governor member is provided with a plurality of balls 11 that are connected to toggle joints 12 formed by the links 13. The links 13 are pivotally connected to the ring 14 that may be suitably pinned" to or otherwise suitably sethe collar 15 will rotate with the spindle 7 and yet may be moved along the spindle. A compression spring 17 is located intermediate the.

ring 14 and the collar 15. As is well known in connection with such governor members the balls 11 will cause the depression of the collar 15 against the elasticity of the spring 17 and according to the speed at which the spindle is rotated. The governor member is located in the shell section 2 of the shell 1.

The spindle 7 is-also provided with a cam 20. The cam 20 is provided with as many raised oints as there are cylinders on the engine wlth which the timer is electrically and mechanically connected and a pair ofcircuit closers 21 and 22 are supported in the section 3 of the shell so as to .be opened and closed bythe cam '20. The circuit closers are located in the primary circuit of the induction coil or transformer of the ignition circuit and when closed establishes a magnetic circuit of progressively increasing density or intensity until the clrcuit closers are opened,

thereby producing inductively a high tension the engine 1n the manner well nown in the art.

Also on the spindle is located a distributor member 25 which makes contact with the contacts 26 in succession as the spindle 7 is rotated. The distributor member 25 is connected in the circuit of the secondary coil and the spark plugs in the engine are connected with the contacts 26 and thus the secondary circuit is established with the spark plugs in succession and in the desired intervals according to the cycle of operations of the engine c linders. The distributor member is locate in the shell section 4 of the shell 1.

My invention particularly provides a means for varying the riods in which the primary circuit is closed in advance of each ignition of the spark plugs automatically according to the speed of the engine and at the same time to automatically alter the location of the period with reference to the cycle of o ration of the particular cylinder in which t e i nition is to take place accordin to the spec of the engine. With this 0 ject in view, I have provided two circuit closers that are located in parallel circuits which may be opened at the same time or at different times so as to vary the lengths of the periods in which the primary circuit is closed, means being provided for shifting one of the circuit closers relative to the cam 20 which is connected to the spindle 7, and relative to the other circuit closer and for shifting both of the circuit closers relative to the cam 20, to advance 'or retard the time, at which the circuit closer that is actuated later by the cam, is opened and at the-same time to shift both circuit closers to prevent over-lapping of the periods of circuit closer and to produce full opportunity for the primary current to build the magnetic circuit in the transformer, or the induction coil, to substantially the maximum andalso opportunity for the full and complete subsidence of the'magnetic lines of force to their minimum. This control of the length and the timing of the periods of the closer of the primary circuit is attained by means of the cam member 30 that is connected to the slidable collar 15or is formed integral therewith. The cam member 30 is so constructed and mounted as to shift the circuit closers 21 and 22 about the spindle for short angular distances. 1

The cam member 30 has a hub part 18 that surrounds the spindle 7 ,the said hub part 18 has a slot 19, and the collar 15 is provided with fingers 29 that engage in the slot 19 whereb the cam member 30 may be shifted along t c axis of the s indle 7 while the collar 15 is not only shi ted along the axis of the spindle "7, but is also rotated with the spindle. The circuit closers 21 and 22 are supported on plates 31 and 32 that are slidably supported in the shell section 3. The plate 32 is sup orted on the bottom of the shell and may e secured in position by a suitable lug or rib 33. The plate 31 is supported on a ridge 34 and in a plane above the bottom. It also may be held in position and guided by a lug or rib 35. The circuit closer 21 is mounted on the plate 31 while the circuit closer 22 is mounted on the plate 32 and so as to be actuated by the cam 20. A pair of spring members 36 and 37 are connected to the wall of the section 3 of the shell 1 and are so formed that they will elastically press the movable parts of the circuit closers towards the cam and the fixed contacts, and at the same time adapt themselves to the short angular displacement that is produced by shifting the plates 31 and 32 to vary the relation between the times of olosin and the times of opening of the primary circuit and the shifting of the times of opening for the purpose of advancing 'or retarding the ignition of the engine cylinders.

The plates are shifted by the operation of the cam member 30, that is, moved by the overnor member 10. The cam member 30 as, preferably, two parts 40 and 41, each of the parts having cam portions located on their ends. the bottom of the shell section 3 and between the plates 31 and 32. The plates 31 and 32 have slots or notches 42 in which the edges of the cam parts 40 and 41 are located. As

the cam member 30 is'moved along the axis of the spindle 7, the cam portions of the cain member 30 operate to shift one or the other of the plates; The cam parts are so formed The cam parts extend through that when one cam part operates to move the plate in one direction the other cam part per-' mits this change in position, the said cam parts being so shaped as to maintain the ends of the notches in close relation to the cam portions and thus prevent any undue shift mg by reason of cam portions being drawn away from the edges of the plates. Thus the plates will be held in proper position by the portions of the cam parts.

The cam member 30 has the cam portions 43 and 44 that cooperate to shift the plate 31 and the cam portions 45 and 46 that cooperate to shift the plate 32. As the speed of the engine increases, the cam member 30 is drawn down by the operation of the governor member 10 and the cam portion 43 shifts the plate 31 and consequently the circuit closer 21 is carried around a short angular distance to the axis of the spindle 7 and in the direction of rotation of the cam located on the spindle. At the same t me the cam portion 46 operates on the plate 32 to shift the said plate and, consequently, the circuit closer mounted thereon in the same circular direction that the plate 31 is shifted but through an angle of lesser degree. This causes the cam 20 to permit closing of the circuit closer 22 by the operation of the spring 37 before the closing of the circuit closer 21 and, consequently, the circuit closer 21 will open after the opening of the circuit closer 22. In the construction shown, the opening of the circuit closer 21 at all times determines the sparking or ignition instant while the closing of the c rcuit closer 22 determines the instant at which the lines of force begin to build" in the magnetic circuit of the induction coil or the transformer. The cam member 30 thus operates inthe manner described to increase the angle of the movement of the spindle 7 during which the circuit is closed as the speed of the engine increases, or to state it another way, the cam member 30 operates to substantially maintain the period of closure of the primary circuit in advance of each ignition constant. notwithstanding the change in speed of the engine. and thus produces an" economical and uniform sparking condition in the ignition system of the engine. This is due to the fact 3 that the cam portion 43 has a greater angular slope than the cam portion 46. The cam portions 43 and 44 have substantially the same slope since they are located in notches on opposite sides of the spindle 7 in the plate instant in the cycle of operations of the engine. It also reduces the angles of the movement during which the prima circuit is closed, or it continuesto maintam the periods of closure substantially constant or such as to be economical insofar as battery consumption in the primary circuit is concerned.

The timer is connected in the usual way in the ignition system except that the circuit closers 21 and 22 are connected in parallel in the primary circuit which is formed on the battery 50, primary coil 51 .and circuit closers 21 and 22. The condenser 52 is connected in parallel with the contacts of the circuit closers. The secondary coil 53 is connected to the ground or frame of the automobile through the battery 50 and to the distributor member 25 that makes contact with the contacts 26 as it is rotated by the spindle 7. The contacts 26 areconnected with the spark plugs 27. The circuit closers 21 and 22 being mounted on rotatable or angularly movable plates '31 and 32 are shifted by the operation of the cam portions 43 and 46 whenthe speed of the engine increases and by the cam ' portions 44 and 45 when the speed of the engine decreases. Since the cam portion 46 has a lesser angular slope to the direction of movement of the cam member as compared to the cam portion 43, the circuit closer 21 is moved through a greater degree angular than the circuit closer 22 as' the speed of the engine increases whereby the periods of closure are maintained in an economic relation as to battery consumption and efiicient ignition. When the speed of the engine decreases the reverse movement is performed by the circuit closers relative to the cam 20 by which they are actuated and relative to each other to maintain the same economic and eflic ent condition.

The circuit closers 21 and 22 are provided with long wiping blocks 48 over which the raised parts of the cam move, the surface of the said blocks being so formed that the circuit closers will be gradually moved away from the axis of the cam without being struck with such a blow as to cause the circuit closers to be thrown away from the cam. The surfaces of the cam 20 and the blocks 48 are so designed as to maintain the blocks in contact with the surfaces of the cam, except during circuit closed periods. notwithstanding variation in the speed of the engine. As shown in Figs; 3 and 4, the blocks 48 are convex where they are engaged by the raised portions of the cam and have a relatively wide area so that the raised portions of the cam will sequentially contact each of the blocks to produce a relatively gradual rise or movement of the circuit closers with reference to the axis of the cam.

I claim:

1. In a timer for ignition systems of an engine. a pair of circuit closers, the primary circuit of the system completed through the circuit closers, the circuit closers being connected in parallel in the circuit, a cam for operating the circuit closers, means connected to the circuit closers for shifting the circuit closers one relative to the other for increasingthe len th of time that the primary circuit is close as measured in degrees of rotation of the cam.

, 2. In a timer for ignition systems of an engine, a pair of'circuit closers, the primary circuit of the system completed through the circuit closers, the circuit closers being connected in parallel in the circuit, a, cam for operating the circuit closers, means connected to one of the circuit closers for shifting the circuit closer relative to the cam for increasing the length of time that the primary circuit is closed as measured in degrees of rotation.

3. In a timer for ignition systems of an engine, a pair of circuit closers, the primary circuit of the system completed through the circuit closers, the circuit closers being connected in parallel in the circuit, a cam for operating the circuit closers, means connected to one of the circuit closers for automatically shifting the circuit'closer relative to the cam for increasing the length of time that the primary circuit is closed as measured in degrees of rotation according to the speed of the engine.

' 4. In an ignition timer, a pair. of circuit closers, a cam for operating the circuit closers, means for causing the circuit closers to advance their opening times according to the speed of the engine and to different extents, the difference in their extent of advancement being also according to the speed of the engine.

5. In an ignition timer for internal combustion engines, a pair of circuit closers, a cam for operating the circuit closers, an engine governor member, means interconnecting the engine governor and the circuit closers for opening the circuit closers simultaneously at low engine speeds and to open them at different times at high engine speeds.

6. In an ignition timer for internal combustion engines, a pair of circuit closers, a

cam for operating the circuit closers, an engine governor member, means interconnecting the engine governor and the circuit closers for opening the circuit closers simultaneousl at low engine speeds and to open them at di erent times at high engine speeds, and to shift the combined closure period preceeding engine ignition according to the speed of the en inc.

7. In a timer or ignition systems of an engine, a pair of circuit closers, a cam for operating each circuit closer, means for rotatably supporting the circuit closers, means for angularly moving the circuit closers according to the speed of the engine.

8. In a timer for ignition systems of an engine, a pair of circuit; @Tmsera J5me @pem :zvting each circuit clossr, means iEQ-l? TO'ZJMEQIQEXST supporting the circuit dmsms, mews Em am guiafly moving the cimui' c clossrs; mcwdjng "so the speed; of the aengine @1161 means Em V8, rying the movemeni; of one circuit dos??? ML ative to the mnvement of the other circui'b closer accordin to speed of the engine, In testimony whereof I have hereunm m signed my name to this specificatione MARIGN EMLLLRYO

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