US1512673A - Internal-combustion engine - Google Patents

Description

Get. 21 1924. 1,512,673

L. BREGUET INTERNAL COMBUSTION ENGINE Filed Nov. '7, 1922 :5 Sheets- 521?- 1 I IIU'U'GTI/t T y 1 u I Attorney;

Oct. 21 1924. 1,512,673

L. BREGUET INTERNAL COMBUSTION ENGINE Filed Nov. 7, 1922 3 Sheets-Sheet 2 Attorneys L. BREGUET INTERNAL COMBUST ION ENGINE Filed Nov. 7, 1922 3 Sheets-$hoot 5 2112/ 711 tor Q :4, f" M-q y Patented Oct. 21, 1924.

UNITED STATES PATENT OFFICE.

otus nnnoun'r, or rams, nnancn, assrcnoa T socmrnanomn nns a'rnnmas n'am'rzon LOUIS BBEGUET, or rams, rnancn INTERNAL-COMBUSTION ENGINE.

Application filed November 7 1922. Serial No. 599,594.

To all whom it may concern Be it known that I, LOUIS Bn'nounr, a citizen of France, and a resident of Paris, France, have invented new and useful Improvements in Internal-Combustion 1 Engines, which arejullyL set-forth in the following specification.

The present invention relates to an in ternal combustion engine which is chiefly 10 applicable to aircraft, and in which the crankshaft speed. may attain and even exceed the known speeds of engines of the explosion type, contrary to what prevails for internal combustion engines of the Diesel type. For these latter engines it is impossible to obtain a high crankshaft speed by reason of the slow rate of combustion of the liquid fuel which takes place by 'deees and is enerally incomplete.

In the engine according to this invention,1

the combustion is not efiected, in a progressive manner but is immediate and complete, by reason of the preliminary and. int1mate mixture of all the particles of the combustible and of the air necessary to obtain the entire combustion. To this end, the air is compressed on the adiabatic principle in the useless space of a compressor cylinder and it-is brought into the ower cylinder through a passage wherein t e spraying of the fuel takes place, so that each particle of fuel shall be in contact with the molecules of air r uired for its total combustion. Ignition is normally obtained by-the 86 high temperature of the air due to the preliminar compression, or by contact between the car ureted mass and a wire heated to incandescence by the electric current, or a like incandescent body.

on the other, hand, it is recognized that the power of an internal combustion engine will vary according to the density of the air-contained in the cylinders after the suction has taken place, and hence the ower is found'to decrease with the altitu e for thedensity of the air then diminishes.

The present invention accordingly comrises a special injection device for liquid el, as well as the use of an auxiliary. .com-

pression cylinder of the double-acting ty e which affords an additional supply for t power cylinder. I

The following description, to ther with the accompanying drawmgs whic are given or the driving iston rods.

Fig. 1 is an e evational view of the section four'compression cylinders disposed in pairs,

and Fig. 5 is the corresponding plan view.

Fig. 6 shows the complete cycles of the englue and compressor.

Fig. 7 is an elevational view of the section of the injection device, and Fi 8 is a horizontal section on the line X- of Fig. 7

The following description relates to-an engine having but a single power cylinder, but it is obvious that an engine may be constructed with any suitable number of pairs of compressor cylinders and power cylinders in combination.

The power cylinder 0., Fig. 1, is mounted together with an auxiliary compressor cylinder b which is connected therewithby a passage of suitable shape 0 formed in the cylinder-heads. Cylinder b is provided with the inlet valve d and discharge valve 6 closing the passage 0. The exhaust valve f is mounted in the head of cylinder a. A fuel injector g is mounted upon the passage 0. The two pistons k, Z are disposed respectively in the cylinders a, b, and the piston rods m, n are connected with the crankshaft o, whereof the cranks p, q are spaced at an 'angle a, Fig. 3, such that the piston Z will have a certain calculated lag behind piston 70.

If the engine is supposed to in operation at the end of the combustion period, it is owerved that the valves e and f are now closed; the gas burned under presence will expand. thereby driving the piston in the sense of the arrow 1 so that said pistonwill rotate the crankshaft b rod m as indi by the arrow 3, Fig. 2. on near the lower dead center, the valve i will open with the proper lead upon the exhaust, and piston k then rises according to the arrow 2 expo t the burnt gas; when near the upper center the valve f is closed.

Concurrently, at the end of 00101711,

of an engine with four power cylinders and 'sure through the open valve d.

tion period, the piston l which is actuated by the action of the crankshaft and piston rod n, will draw in air at atmospheric pres- Shortly after the lower dead center, valve d closes and the piston l which continues its movement will compress in an-adiabatic manner the air in the compression chamber 1' which is made as small as possible, that is, the chamber is reduced to the useless space which is unavoidable. Before the upper dead center is reached, the valve 6 o ens, and the air compressed for examp e, at 50 kilograms per square centimeter proceeds through the passage 0 into the power cylinder 1); at the same instant, liquid fuel is injected in a fine spray from the injector g into the passage 0, and each particle of the fuel is instantly and entirely ignited upon contact with the molecules of air which have been hi hly heated by the adiabatic com ression. ft is observed that the action 0 the said passage isquite analogous to that of a carburettor as well as a pressure burner, and the speed of combustion will vary directly as the speed of carburation; the latter depends directly upon the flow of air in the passage 0. This output is determined by the cross-section of the passage and by the differences of pressure in the com ressor and the power cylinders, these di erences depending upon the differences in volume and consequently upon the cylinder bore and. stroke. When the piston of the compression cylinder has driven into said passage all the air under compmsion, the valve 6 will close and the fuel injection also stops; the burnt gas expands, and the same series of operations continues.

W'ith the said invention, the power cylinder can be given the proper volume in order to obtain the maximum power from the volume of air compressed by the cylinder, that is, if the volume of cylinder a is double that of b, the expansion Wlll be such that the power obtained will be greater than \what could be obtained from a cylinder of the same volume as b, and furthermore, the gas will be cooled to a greater degree by reason of this expansion. For this reason the exhaust valves and the valves (1 and 6 will not be brought to a red heat, as in most en ines, and they will therefore have a longer uration.-

In the engine having four elements (or power and compressor pairs) Figs. 4 and 5, each pair comprises a com ressor cylinder 1 having two cycles mounted together with a power cylinder 2, connection between cylinders being made by the passage 3 of proper shape formed in the cylinder head. linder 1 is provided on the upper head wit an inlet valve 4 and on the lower head with an inlet valve 5, a stop screw 6 and a stufling box and guide 7 for the rod 8 of piston 9;

the head of cylinder 2 is provided with the exhaust valve 10, and the two cylinders are cut off from each other by the closing of the injection valve 19.

Two pistons 9, 11 are disposed respectively in cylinders l, 2. Piston 9 is connected with the crankshaft 8 b a rod 13 and the projecting portion 8 sli able in the tight stufiing box 7 piston 9 has formed therein an aperture l4 closed normally by a valve 15 urged upon its seat by a calibrated spring 16. When at the bottom of the piston stroke the valve stem comes into contact with the stop screw 6. Piston 11 is connected with a second crankshaft 17 by a rod 18.

Suitable means are provided such as gear ing, chains, connecting rods and the like, in order that the crankshaft 17 shall drive the crankshaft 12 in a synchronous manner, that is, that the number of revolutions per minute of the crankshaft 17 shall be exactly the same as that of crankshaft 12. The cranks 18, 13 of the pistons are preferably given an angular spacing so that the iston 11 shall have a certain lead with re erence to piston 9. Fuel is injected through the small oles 3 provided at the center of the passage 3 and connecting the latter with the fuel feed passage 3"; the fuel is supplied in proper amount in the said feed passage b an ad justable pump of a suitable type. he holes 3 are closed by the injection valve 19 of drum shape which is urged u on its seat by the spring 20 which is secure at one end to the stuffing box 21 and at the other to a washer 21 attached by a pin to the rod of said spring; at the upper end of said rod is mounted a washer 23 serving as a support for the spring 24 which is controlled by a fork 25 actuated by a cam 26. The tight workin of the injection valve is ensured by the stu box 21 and also by the fact that the top 0 said valve drum is caused to fit when the valve is raised upon a ground seat formed in the ca of the stuffing box 21.

The power an compressor cylinders can be cooled by a water jacket 27, by cooling fins 28 or by like means. Any suitable control can be used for each of the inlet, injection and exhaust valves, such as trip levers, cam shafts, gearing and the like.

The operation of the said apparatus is as follows:

If the engine is supposed to be operating at the end of the combustion period, the passage 3 has now been closed by the valve 19 and the fuel and air injection In the compression 0 linder, the valves 5 and 15 are closed. The valve 4 is adapted to open under the action of the cam shaft; the crankshaft 12 driven by crank 17,- which is actuated by the descent of piston 11 on the power stroke-will move according to the arrow A (by rod 13 and projection 8) the piston 9 which will compress the air in the lower chamber and draw air from the atmosphere into the upper chamtion, and. piston 9 continuin cording to the arrow B-wil draw air at atmospheric'presi1reinto the lower chamher, at the same time effecting the adiabatic part or 1g. 7,

her through valve 4:. When near the lower dead center, the valve 4 closes, and valve 15 bearing upon the stop screw 6 is lifted (the valve spring being calibrated so that the valve Wlll not open by itself under the pressure of I the air compressed in the lower chamber) and opens the aperture '14 throu h which the compressed air flows into t e upper chamber. As soon as the piston rises, the valve 15 which no lon r cooperates with the stop screw 6 will fal upon its seat by means of spring 16, closing the aperture 14; valve 15 then opens by the normal sucto move accompression of the air in the upper chamher until the latter becomes reduced to the useless space which cannot be avoided in practice, the air being compressed for example at kilograms per square centimeter atvthe end of the piston stroke. At the same time the piston 11 when rising has expelled the burnt gas through valve 10.

. Shortly before the upper dead center, the

injection valve 19 is lifted so as to uncover the injection holes, and the liquid fuel under ressure, proceeds therefrom as fine spray mto the assage 3 and thence into the cylinder 2 a ove the piston 11. llnasmuchas each particle of the spray is in intimate contact with the molecules of the highly heated air, it will be at once ignited and entirely consumed; the device as a whole will act as well-regulated burner, the rate .ot combustion of the burner depending only upon the difierence between the ressures in cylinders 1 and 2. When the va ve 19 rises, its upper beveled part will fit into the like seat in the cap of the stufiing box 21, in order to increase the fluid-tight action of the latter. p I

When the piston has driven into the the valve 19 is pressed on its seat by the spring 20 and closes the passage 3, arrest' at the same time the injection of combustible. The burnt gas expands, impelling the piston 11, and thisaction corresponds to the wer stroke; the'stroke which has just been will again commence.

It is observed that the rateof combustion will be regulated by the rate of flow of com pre air through the said passage, and this rate of flow'will do nd upon varies tions in'the bore and stro in the two cylinders or upon theangular spacing oiwthe dead centers of the pistons, or agam,' pon variations in compression of air in the compr cylinderwhich are brought about y varying the closing'of valves 4 andli by a set of adjustable cams controlled by the cylinder 2 all the airwhich it oomwithin a certain limit, or up to 6000 meters,

at which height the density of the air is about one-half the density at the ground. When near the ground, the valve 5 may be left constantly open so that piston 9 shall not compress air in the lower chamber, and when the altitude increases and the aircraft is flying at high altitudes of 5000 to 6000 meters, the valve 5 will close as soon as the lower chamber is filled, and the. whole volume drawn in will proceed into the upper chamberafter being compressed, and thence into the power cylinder 2.

For intermediate altitudes between 0 and 6000 meters, the pilot may set back the time of closing of the valve 5 by using a series of adjustable cams acting for instance by means of rods 31 or rockers 32, so that only a part ofthe air drawn in will remain in the 'lower space of the cylinder 1, and only the said portion will pass through the valve 14 into the upper chamber of the cylinder 1; the pressure in this space, which had been reduced on account" of the rarefaction of the admitted air at the given altitude, will be restored in this manner; Use might be, made of an aneroid barometer chamber for the control of the cam for valve 5, whereby the pressure in the upper space of said cylinder shall be maintained constant as far as 6000 meters in an automatic manner.

Should it be'desired to employ the said engine at altitudes above the maximum,.for instance 6000 meters, for which the compressor is designed, the cylinder 2 may be used as a com ressor in order that the volume of admitted air shall remain the same as when on the ground, as far as possible; in this event it is simply necessary to provide the superposed ports 29 and 30 in the cylinder 2, these being so disposed that the piston 11 when at the bottom of the stroke shall attain the lower level of port 29 so as to entirely open the same; said port is connected by suitable iping with an air fan or the like which-dc ivers air into cylinder 2. The port 30 discharges the burnt gas to the atmosphere,

In these conditions, if the discharge valve 10 is constantly closed for example by raising the cam shaft controlling the same, the

r passing through the lower dea center,

the piston 11 rises according to arrow B, successively closing the ports 29 and 30, and compressing the pure air in the top of cylinder 2 after the port 30 is closed. This air serves for the combustion of the excess of sprayed fuel supplied by the said injection device. By means'of the said arrangement which is applied to the compression cylinder, the engine 18 enabled to maintain its power, save for ressure losses and leakages, as far as altitu eson the order of 10,000 meters, provided the power cylinder has about double the volume of the compression cylinder. The conduits connected with the ports 29 and 30 can be closed when not in use by any suitableimeans, such as cocks or valves.

Obviously, the present invention may be carried into efiect by the use of any desired number of power cylinders, each with the corresponding double-acting compression cylinder. The cranks of the crankshaft 17 are properly set in order that the shaft may operate with the required uniformity. If desired, all the cranks might :be disposed upon a single shaft, and the passage 19 might also be cooled by suitable means.

In the drawings, the said passage is cooled by the jacket 27 for one-half the length, but this could beextended to the entire length, or use could be made of a separate jacket provided with a rapid circulation. The compression cylinder 1 may H alsobe cooled by a water jacket.

A simpler apparatus may be provided in which a high compression is not used, and in this case the compressor 9 may be singleactin or in one cycle; the lower surface of cylinder 1 is now open to, the atmosphere, and the valve 15 is eliminated, the rods 13 and 18 are preferably connected with a common crankshaft.

Obviously, the shapes, sizes, details and material are susceptible of all necessary variations without departing from the principle of the invention.

What T'claim is:

1. An internal combustion engine comprising a power cylinder, an air compression pump cylinder adjacent the same, a

passage connecting said cylinders, means for closing off said passage, a compression piston in said pump cylinder, a positively controlled air suction valve mounted in the cylinder head of the pump which is provided with said passage, a second positively controlled air suction valve mounted in the opposite head of said ump cylinder, an automatic valve mounted on the pump piston for the flow of air from one side of the piston to the other, means for in'ecting fuel into said assage during the ow of compressed air rom the pump to the power cylinder, whereby the fuel is sprayed and the sprayed comibustible will be immediately and totally consumed in contact with the molecules of compressed and highly heated air before entering the said power cylinder.

2. An internal combustion engine comprising a power cylinder, an air compression pump cylinder adjacent the same, a passage connectin said cylinders, means for closing off sai passage, a compression piston in said pump cylinder, a positively controlled air suction valve mounted in the cylinder head of the pump which is provided with said passage, a second positively controlled air suction valve mounted 1n the opposite head of said pump cylinder, an automatic valve mounted. on the pump piston for the flow of air from one side of the piston to the other, means for injecting fuel into said passage during the flow of compressed air from the pump to the wer cylinder, whereby the fuel is spray and the sprayed combustible will be immediately and totally consumed in contact with the molecules of compressed and highly heated air before entering the said power cylinder, a port provided at the lower part of the power cylinder for exhaust of burnt gas, a second port the bottom of which is brought into coincidence with the top of the power piston when the latter is at the lower dead center and serving as an inlet for compressed air for scavenging purposes and for filling the power cylinder with fresh air.

lln testimony whereof 1 have signed this specification.

LOUIS BREGUET.

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