US1107501A - Internal-combustion engine. - Google Patents

Description

C. E. DURYEA.

INTERNAL GOMBUSTION ENGINE.

APPLIUATION FILED Amma, 1910.

1,107,501 Patented Aug. 18, 1914.

2 SHEETS-SHEET 1.

THE MORRIS PETERS CO., PHOToLlTHo.. WASHING roN, D, C.

C. B. DURYEA.

INTERNAL GOMBUSTION ENGINE.

APTLIUATION FILED APR.28, 1910.

1,107,501. Patented Aug.18,1914.

2 SHEETS-SHEET 2.

THE Nnnnm PFM-Ps co., PHoTo-LlTHo, WASHINGTON, D. C, I

CHARLES E. DURYEA, OF READING, PENNSYLVANIA.

INTERNAL-COMBUSTION ENGINE.

Specification of Letters Patent.

Patented Aug. 18, 1914:.

Application led April 28, 1910. Serial No. 558,235.

To all 'whom t may concern:

Be it known that I, CHARLES E. DURYEA, a citizen of the United States of America, and resident of Reading, in the State of Pennsylvania, have invented certain new and useful lmprovements in Internal-Combustion Engines, of which the following is a specification.

My invention relates to the class of internal combustion engines commonly termed two-cycle wherein the piston uncovers an exhaust port near the end of theworking stroke and wherein the next charge is, by the same motion of the piston, lightly compressed in the crank box and by this com pression is transferred to the cylinder ready for compression by the piston on its return stroke.

The objects of my invention are the overcoming of some of the defects of the usual type of two-cycle engine as well as the attainment of speeds usually considered beyond the practical range of this class of engines. Among these objects may be mentioned means for insuring more complete introduction of explosive mixture or air into the crank box, more direct transfer (and with greater completeness) of the charge to the firing chamber, better cooling of the piston head and cylinder head, less admixture of thenew charge with the old during the expulsion of the old and admission of the new, positive ignition of the new charge at the right time and place, simplification of the ignition system and of the construction of the engine, particularly with regard to the heated condition under which a high speed engine, especially if air cooled, must work, and a number of other objects which will appear in the specifications herewith. I accomplish these objects by the mechanism shown in the accompanying drawings in which- Figure l is a sectional elevation of the parts embodying my present improvements and such other parts as are necessary to a proper understanding thereof. Fig. 2 is an end view looking at the interior of the piston. Fig. 3 is an end elevation of the opposite end of the piston removed. Fig. l is an enlarged cross section on the line 4-4 of Fig. 1. Fig. 5 is a perspective view of the mounting and housing for the spring.

Similar letters refer to similar parts.

The explosive charge is admitted in the usual way from any preferred form of carbureter to the crank box.

From the crank box it the mixture is passed through a valve c in the head d of the piston. It is well known that the center of the piston is the place most ditlicult to cool 1n most engines. By passing the fresh mixture through it, this objection is overcome. Here I lit a very large valve c and make this of spheric section so that it will take the pressure of the explosion with very little amount of metal. Further I support this valve c and stem well up into the spheric portion so the weight of the end of the stem and the spring attached thereto, `balances the weight of the head and the valve has no tendency to drop down at the head and fail to strike its seat properly. This mounting fits it to the horizontal type of motor without placing the valve cross wise the axis of the piston as has been done. I provide in this mounting d2 a housing for the spring cl3. This serves several purposes. It insures that a broken valve stem does not get loose and into the crank case where it might get under the cranks and damage the case. Also that the spring da is housed from the larger part of the volume of the charge and so is not exposed to heat if this charge should by chance take re while in the crank box and rush out past the spring while hot and burning. Such exposure would heat and destroy the temper of the spring.

vlln order that the fresh charge may not mix with the old charge excessively, I provide a nozzle Z4 to the piston and direct the charge up toward the center of the cylinder head in a round stream of small circumference and cross area and consequent rapid speed. The opening of the nozzle Z4 is less than the diameter of the valve c so if the valve should break from its stem or mounting d2 itl could not get out into the cylinder proper and be the cause of damage. The nozzle Z4 is also preferably small so that it may not expose a large area to the burning charge when ignited and it is made a part of the piston so that the heat may be carried by the continuous metal kdown to the walls of the piston and there be cooled by ioo contact with the cool walls of the cylinder. The cylinder head e is made spheroidal, somewhat elongated, so as to provide 'room for the nozzle and so as to lbest mass the stream of new charge and retain it in the cylinder head instead of letting it pass down the walls and out the exhaust ports f f. In the more common constructionswherein the new charge is admitted by a port uncovered by the piston shortly after' the exhaust ports are opened, the new charge is turned up one side of the cylinder with the result that does not mass in the head but largely by its inertia rushes" ver'tle t0n and down and out the other side with'the exhaust. rIhis is specially'true of engines having hemi-spheric heads yyet it is well known that the hemi-spheijic shape of head offers least wall surface to absorb heat.

In the Imore common CODS'Kruction the ports must extend well aro-und the cylinderl circumference in order to get the new charge in and the old charge out quickly and even under most favorable conditions', authorities on' two-cycle automobile engines assert that the exhaust ports should be uncovered nearly 600 before dead center.l Such uncovering results in waste of power and a noisy y exhaust. I, by extending the exhaust ports i all around the cylinder with such bridges as o are necessary for' strength .and to hold the rings in place tothe piston, can run at high speed with exhaust ports which uncover but oto 100 ahead of dead center, about half l the usual distance from Adead center. This adds tothe power and economy ofthe en-g gine but does not materially lessen the time for admission due to the fact that the valve c in the piston is verylarge and so can let the transfer be made quickly and also that it v can open just as soon as they pressure is off of it and remain open till theexhaust port is closed and the pressure on the working side o f the valve as great as that on the crank box side.' This method of admission pre'- vents any possibility,V of rush of burning gases back into the crank box and insures that the old'charge is expanded and cooled by this expansion below the burning point before thek new is admitted by thev opening of the valve, irrespective of the engine speed. It is also readily seen that Yin high speed engines of the vmore common WP?, the short space between the two ports offers a ready passage for gases under compression in the crank box to pass around the piston parallel to the usual piston rings and escape into the exhaust passage, or when there is vacuum in the crank box, for the burned gases in the exhaust pipes to be sucked back into the crank box to a greater or less extent; In engines which are run quite vcool the oil will largely pack this space but in automobile and aeronautic work where cooling water is not rreadily had, the oil gets very'hot and thin and so does not offer much hindrance to the passage of gas in eitherdirection as stated. This is particularly true in air cooled engines where pistons are made considerably smaller than the cylinder bore to allow for expansion.

I show in Fig. l the construction of piston which consists of the shell of which the nozzle cl* forms part, the head CZ and the valve mounting cl2 which also serves as a stand for the piston pin bearing g g. The said bea-rings g g, the mounting cl2 and the head CZ are all held in place by studs 72, 71, fastened to the piston proper and having nuts z' zf. on their ends tof bind the bearings and all parts Vtogether; By this constructiomthe pistone-pin bearings never get hot for they have very little connection with hot vparts and are cooled by the rushof the new charge by them on its way to the cylinder proper. The valve action I have described prevents the fresh gas from being exposed tothe old till the pressure of the 'old haspassed away on which account there is very little likelihood that there*v will be backring into the crank case butto prevent this even in case the valve spring d? should break, I insert a screen of woven wire c between the piston head Zand the valve mounting d?. Thisl has a very large area and so offers very little resistance to the passage of the gases. e It is not likely tov clog easily and if clogged can be reinoved and cleaned easily, when the piston is out of the engine.` One of the requirements of an automobile engine is that it be flexible. n That is, it must be capable of ruiming at low speeds and under the action of atluottle as dees a steam engine. In the common two cycle engine throttling results in less admission of mixture from the crankcase and as a result of this more of the old gases are held in the cylinder. This dilutes the new charge veryv much and makes the engine likelyv to miss fire through failurel to ignite the little new charge that was admitted. My construction causes the little new charge admitted to pass into and through the noz-- zle Zt washing out the old ahead of it and remaining in the nozzle quite fully.` I then provide a spark forignition in the nozzle and thus make sure that the fresh charge however small will ignite because it is un` diluted or not largely diluted. Further by igniting the charge farthest from the exhaust ports 'I insure that this gas ismost fully burned when the exhaust opens Vand is therefore most sure to be not burning when the fresh charge enters, thus again 'insuring that at'high speeds the engine will not fail to function properly or backfire.

I show in Fig. l a formv ofinake and break sparker which issuited to my use. This consists of a plug 76 screwed or fas-r tened into vthe cylinderfin any well known manner. The end of this plug 7c has a` pivoted lmovable electrode Z attached thereto and of such shape that mo-tion of the piston against its shorter end will lift the longer end away from the insulated electrode m. These Contact ends stand slightly out of the center line of the plug and this permits the insulated electrode m to be eccentric at its end and be adjusted forwear or time by slightly twisting it. The movable electrode Z has a push rod a bearing against the outer surface of its short arm, and far out from the plug body is a spring 0 which keeps the two points in contact. The location of this spring 0 keeps it from the heat far enough to insure its temper remaining intact. It is evident that if the end yof the piston nozzle (Zt contacts with the short arm of the electrode Z it will separate the contact points and cause an electric arc if current is flowing at the time of the separation. But it is well known that for high speed the spark should occur some time in advance of the need of power so as to give the explosive mixture time to burn. This spark advance is usually gotten by some manually controlled device but, especially in aeronaut-ic work, it is essential that as few controlling devices as possible be present. I therefore fit to the nozzle Z4 a loose bar Z5 headed at each end and sliding in a guide hole provided therefor in the structure of the nozzle (Z4. The bar Z5 is longer than the guide hole and will move lengthwise the pistons so far as this excess length will permit at each piston stroke if the piston is moving fast. If the piston is moving slowly, as when turning the engine over by hand, the bar Z5 will simply move with it and will break the sparker circuit when the piston is almost at the proper dead center. This will be too near the dead center for the engine to reverse its direction or back-kick. But when the piston is moving fast, rapidly acc-elerating its motion to the center of its stroke and as rapidly retarding to the end of the stroke the bar @Z5 will accelerate with the piston but being longer than its guide and therefore free to move with relation to the piston will not retard with the piston but will throw forward to the limit of its movement and arrive in contact with the arm of the electrode Z sooner than if not thrown forward. It will therefore make the spark sooner and give the advanced spark position desired. Instead of a loose bar, other forms of the loose mass may be employed. This method of advance is not a variable method because up to certain speeds it does not advance, then its advance will be uncertain till still higher speeds are reached when it will be found positive in action. By some experiment the proper amount of advance for best average high speeds can be found and the spark position fixed at that point. Practice seems to indicate that this proper advance is about 1g inch of piston movement in an engine having a piston stroke of 4F25 inches. .But the quality of the mixture and the size of the spark s-eem to have some effect on this position. The large spark does not seem to require so great an advance and the power seems to be greater with the large spark. I therefore prefer to supply this plug with electricity from some source of energy which is not scanty or unreliable, particularly at high speeds.

One end of the wire w may be lgrounded on the engine and the other carried to the plug in a single cylinder engine or in the two cylinder engine most used by me, both wires go to their respective plugs. I lubricate these engines by feeding cylinder oil with `the fuel in proportions o-f about one to two pints to each five gallons of fuel, and this not only gets rid of the complications of oilers but feeds oil proportionate to the power and the oil keeps the leather joints from getting hard.

It will be seen that my design not only insures charges of like quality and of large size but that it transfers these charges in the most direct manner to the extreme head of the cylinder cooling the piston, the spark plug and the cylinder head and passing through the old charge with the least presentation of surface to the old charge and forcing the old charge out the exhaust ports most evenly. Further my location of and size of spark insures firing even the smallest charges and firing that part of the charge near the valve early so it may be burned and extinguished before the next charge enters. The spring tension on the valve c holds it against rising except when there is suliicient pressure under it to insure a flow of new charge faster than the usual rate of flame propagation and thus insures freedom from back firing with lean mixtures even if the screen c were absent. My oiling method insures perfect lubrication of the various parts without complexity and loss of power and proportionate to the power being produced. The late opening exhaust ports give increased power and quick escape of the gases as well as even distribution of the heat of the exhaust.

While I have given my preferred method of accomplishing the objects set forth modiiications thereof may be used without departing from the spirit of the invention.

To get the valve e in place, the mounting Z2 is usually made in two parts. The head Z is shown of disk shape but may be coned and fitted to a coned seat for easy removal.

I have described this engine cylinder and the piston therefor as machined inside and out but without specially calling attention to this feature of the design. Such method of making them insures concentricity and `that expansion under the heat of hard workL does not distort them as would likely be the case if they were not concentric and even walled around.

I have found by experiment that if the eX-1 haust opening is not provided on all sides the old charge goes to the open side and is followed by the new with resultant dead space opposite the port. I can therefore place the nozzle of the piston eccentrically and the spar-ker likewise and thus lessen this: dead space but the work of machining is greater in this event and it is only warranted when it is not convenient to cut the eX-. haust port all around (excepting the neces sary bridges for strength, of course). I have; shown the piston pin as supported in bear-- ings held by the studs but it will be evident` that the more common construction wherein the pin is fixed to the studs and the bearings are in the rod end, will serve just as well. I' do not attach the pin to the walls of the piston becaus-e when the piston expands`- under heat the pin does not and this dis. tort-s the piston. The shape of the nozzle has much to do with the results attained, The outer surface makes an easy line for the flow of the exhaust gases and presents no corners to get overhot. The base has much metal in it and large connecting area with the walls of the piston so it draws the heat away from 1 the point rapidly. The point is convergent so as to throw the new charge into a small` round rapidly moving stream and to be cooled by it. It made divergent the point does not properly cool.

I claim- I. In a high speed gas engine, a pistonf having a head and an integral nozzle above? said head and a valve mounting within the, piston and' removable from beneath the head, s said valve mounting being independent ofi the nozzle; u 1

2. In a high speed gas engine, a piston: having an integral nozzle, a head, and a` valve mounting and valve beneath the head, -g

said mounting being independent of the nozzle and mounted within the head and remov- 4. In a high speed gas engine, a piston having an integral nozzle above its head, the head being of greater diameter than the nozzle outlet, a valve mounting, a valve and means detachably supporting said valve and valve mounting beneath the head and permittinw of removal thereof in a direction away :trom the nozzle.

5. In a high speed gas engine, a piston embodying a shell, a nozzle rigid with the shell, a head detachable from the shell and a valve and valve mounting removable from the shell in a direction away from the nozzle,

said valve being located beneath the head and removable by movement in a direction away from the nozzle.

6. In a high speed gas engine, a piston embodying a shell and a nozzle integral therewith, a` detachable head within the shell, means d'etachably connecting said head and shell, piston-pin bearings supported upon said means, and a valve mounting also supported by said means.

7. In a high speed gas engine, a piston shellhaving integral nozzle, studs mounted in said nozzle, a piston head, a valve mounting, a valve within the nozzle of greater diameter than the nozzle outlet and pistonpin bearings supported by said studs, with means for detachably uniting said bearings, mounting and head.

' Signed by me at Reading, Penna., this 15th day of April 1910. CHARLES E. DURYEA. IvVitnesses:

Riina E. DURYEA, D. M. STEWART.

Copies of this patent may be obtained` for ve cents each, by addressing the i Commissioner of Patents, i Washington, I). G.

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