US2621473A - Internal-combustion engine having multiple compression and expansion - Google Patents

Description

CHE GINE HAVING MULTIPLE COMPRESSION AND EXPANSION 5 Sheets-Sheet 1 Filed Aug. 10, 1946 c 4 mm A MN v .m fi A 5/? 1 vw V mw L1 1 m v WT I t a a 0\ 1 J Q\ x Q j m \\N 5 6 N QM Q X L W 6E m Q Jw 1% @m 6% JET. 1% r a m. N Q 3 A.NACCACHE -COMBUST Dec. 16, 1952 ION ENGINE HAVING MULTIPLE INTERNAL COMPRESSION AND EXPANSION 5 Sheets-Sheet 2 fifiln Filed Aug. 10, 1946 hvvau1vn; ALBERT A/ecucu 3v f 5 Z: gr

/ Arromvv s Dec. 16, 1952 A NACCACHE 2,621,473

INTERNAL-COMBUSTION ENGINE HAVING MULTIPLE COMPRESSION AND EXPANSION Filed Aug. 10, 1946 5 Sheets-Sheet 3 TI km 11 111 109 103 702 llvnwran ALBERT A61 renew: M, 14%, y

A Tron/v: r:

Dec. 16, 1952 A. NACCACHE 2,621,473

INTERNAL-COMBUSTION ENGINE HAVING MULTIPLE COMPRESSION AND EXPANSION Filed Aug. 10, 1946 5 Sheets-Sheet 4 bvnwran Azeuar Nqccacx/r m, mu mfw Dec. 16, 1952 A. NACCACHE INTERNAL-COMBUSTION ENGINE HAVING MULTIPLE COMPRESSION AND EXPANSION Filed Aug. 10, 1946 5 Sheets-Sheet 5 //VVNTOR ALGERT Nut-Ac:

Br- E Patented Dec. 16, 1952 INTERNAL-COMBUSTION ENGINE HAVING MULTIPLE COMPRESSION AND EXPANSION Albert" Naccache, Beirut, Lebanon Application August 10, 1946, Serial No. 689,703 In France December 1 2', 1945- 5 Claims.

The present invention relates to gaseous fuel burning piston engines and more particularly to a means for increasing the efiiciency of these engines by compression of the operating fluids and expansion of the inert exhaust gases in stages.

The objects of the invention are to provideimproved means for achieving the five results listedbelow separately or in combination.

First;-Efiecting compression of the feedfluids, whether gaseous mixture or air, by successive stages and in separate chambers.

Second'.Cooling: the. feed fluids after certain stages. of their partial compression.

Third.--Effecting the expansion by successive stages and in separate chambers.

Fourth.--Ef1ecting cooling of the power pistons which effect the final compression and at least the initial expansion, especially the cooling of these pistons by the circulation through their skirts either of feed fluids previously partially compressed and cooled, or else by circulation at high speed of air that has been compressed and cooled.

Fifth-scavenging. of the inert gases of combustion from the engine by a compressed air blast into the combustion chamber at the end ofthe fourth stroke of the power piston in that chamber.

In order to achieve the objects outlined above, compression is. carried out in separate chambers working in series, final compression being effected in the last chamber, that is, the chamber in which combustion occurs and which corresponds to the combustion chamber in a standard 4-stroke cycle engine.

On the other hand, expansion is carried out in two separate chambers operating in series, the initial expansion occurring in the combustion chamber, i. e., the same chamber, in which on the one hand the final compression Occurs, on-

the other hand is the chamber in which initial expansion occurs.

The invention relies especially on the combination with one or more compressors of diiierent receivers 01' reservoirs serving, as it were, as accumulators that allow, in the first place, thestoring up of the fluids compressed and dischargedby one or more compressors; in the second place, the cooling of these fluids; in the third place, the passage of these fluids through the airtight chamber formed by the inside of the pistons for cooling of the pistons; in the fourth place, the feed to the inlet valves of the engine as well as to the valvesthat control the delivery of the compressed air to the combustion chambersrequired to scavenge waste gases; and, in the fifth place, for other useful purposes if required.

Connections and link-ups between the chambers of the. various compressors and the control tanks or reservoirs, between the different tanks or parts of these tanks, and between these tanks and the compression chambers of the engine allow the meeting of the changing problems brought. about. by the various special cases concerned in their employment.

Other features. of the improved engines of the present invention, all: of which are assumed to bevertical for the purpose of illustration, are also brought. out in the. following description, takenbyway ofv example, of the engines illustrated in the accompanying drawings, in which:

Fig. 1 is a fragmentary axial longitudinal. sectional view of' one form. of' engine constructed in accordancev with the principles of. the present invention;

Fig. 2. is a fragmentary side elevational view of the. engine shown in Fig. 1.;

Fig. 3 a. top; plan view of the engine shown in Fig. 1;;

Fig. 4. is. an. axial transverse sectional view ofanother form of. engine embodying the principles of the present: invention;

Fig. 5' is. a fragmentary axial longitudinal sec.- tionof the engine disclosed. in Fig. 4;

Fig. 6' is. a fragmentary side elevational viewof the engine disclosed in Fig. 4;

Fig. 7 is a top plan View of the engine disclosed in Fig. 4; and

g- 8 i a sectional view taken on a substantially diametrical plane through the control valve. and the partition shown in Fig. 4.

Referring to Figs. I to 3, there is, shown an. internal combustion engine having an engine. block 3 which has formed therein a pair of compressor cylinders 11- and 7 la, two driving or power cylinders. 9, 9a and a. pressure, reducing or expansioncylinder '52 into which exhaust gasesare discharged from the two driving cylinders 9, Sa All of these cylinders are arranged. in line and the driving, cylinders are ofreduced diameter relative to the other cylinders.

Reciprocable within the drive cylinders 9 and 9a are hollow drive pistons. I- and la,.and a hollow compression piston l" is. reciprocable in the expansion cylinder 12; These pistons I, la, and!" have ports i6, [6a, and I7, respectively, in, their skirtswhich periodically during the reciprocation of the pistons register with. ports: l8, Isa, and [9' shown in Figure 3 in the side walls of the cylinders 9; 9a and 12. Preferably the power pistons l and la are fourstrokes orone cycle out of phase relative to each other so that one piston is moving through its power stroke while the other is moving through its suction stroke.

This engine has a crank case 25, a fragment of which is shown in section in the lower portion of Fig. 1, and a crank shaft 24 driven by the drive pistons l and la and suitably supported in the crank case for rotation. The expansion piston l" in the expansion cylinder 12 is operatively connected to and driven by the crank shaft, this piston being 180 degrees out of phase with respect to the drive istons l.

The means for feeding gaseous fluid such as a combustible fuel mixture or air to support combustion to the drive cylinders 9 and 9a includes means for passing this fluid through the pistons I, I" and la for the purpose of cooling these pistons. Referring to Fig. 3 it will be seen that a pair of control reservoirs or tanks 5 and 6 are secured by any suitable means on opposite sides of the engine block. Each of these tanks may be provided with suitable cooling means l2 (Fig. 2), such as a water cooling system, which may be of conventional construction. The cooling means in the tank 6 is similar to that in the tank 5, and is not separately illustrated. Thus, any fluid contained in or flowing through these tanks is cooled.

This fluid, which may be a gaseous fuel mixture or air as previously stated, depending on the type of engine, is drawn from any suitable conventional source into the compressor cylinder H through a channel 16 which ha a suitable check valve 80 therein and is discharged through a duct I8 into the tank 5, a check valve 8! being provided in duct 18. From the tank 5 the fluid passes to the second cooling reservoir or tank 6, suitable ports and passageways l8, IBa, and (9 being provided to communicate the tank 5 with one side of the cylinders 9, 9a and 12. Other ports and passageways 23, 23a, and 24 connect the other side of the cylinders with the tank 6 so that the fluid in passing between these two tanks must necessarily pass through the ports in the cylinder walls and through the hollow pistons I, la and I" when the ports in the cylinders and pistons are brought into register by reciprocation of the pistons. Since the fluid is cooled in tank 5 it will absorb a large quantity of heat from the pistons, thereby cooling the latter.

Such heat as the fluid picks up in passing through the pistons I, la and I" is removed in cooling tank 6, the fluid remaining under pressure. From this tank the pressurized and cooled fluid flows through inlet conduits l3 and [3a (Fig. 3) and inlet valves [4 and 14a into the power cylinders 9 and 9a. These inlet valves are driven from the engine by suitable well known mechanism not shown and operate alternately so that one of the power pistons is moving through its power stroke while the other is moving through its intake stroke.

Exhaust gases from the power cylinders 9 and 9a are discharged into the expansion cylinder 12 through passageways 54 and 54a in the heads of the cylinders 9 and 12. Flow through these passageways is controlled by valves 53 and 53a (Fig. 3) driven from the engine by suitable mechanism not shown designed to open these valves alternately upon the suction strokes of the piston I". Upon the compression or exhaust strokes of the piston l" valves 53 and 530, are held closed and exhaust valves 55 (Fig. 1) open to establish communication between the expansion cylinder 12 and the atmosphere through ducts 13 (Fig. 3) for discharging the partially expanded exhaust gases in cylinder 12 to the atmosphere.

Assuming for the purpose of illustrating the operation of the engine that the power piston la, Fig. 1, is at the end of its compression stroke, the power piston I therefore is at the end of its exhaust stroke and the expansion piston l" at the end of its suction stroke. At the moment the inlet valves l4 and Mo to the power cylinders 9 and 9a are both closed while the two inlet valves 53 and 53a to the expansion cylinder [2 and the exhaust valves 55 are also closed. Ignition of the combustible fuel mixture in the power cylinder 9a, which may be made to take place in a conventional manner not shown, and the consequent explosion or combustion of the gaseous fuel mixture causes the gases to expand and the power piston to to be driven through its power stroke. The powe piston I being connected to the same crankshaft 24 as th power piston la is simultaneously driven by this connecting rod through its suction stroke, its inlet valve 14 opening to admit cooled fluid from the reservoir 6 through duct [3. During this time the expansion piston I" being connected to the crank shaft is driven through an exhaust stroke, the valves 55 opening to allow discharge of the partially expanded exhaust gases from the cylinder 12 to the atmosphere while the valves 53 and 53a remain closed.

The power stroke of the piston la is followed by its exhaust stroke during which time the valve 53a associated with the cylinder 9a opens to admit exhaust gases from this power cylinder to the expansion cylinder 12 and the expansion piston I is moved through its intake stroke to allow the exhaust gases from the power cylinder 9a to expand partially. All other valves remain closed, and during this time the power piston la is moved through its compression stroke so that the parts are again in the position shown in Fig. 1.

Upon completion of the compression stroke of this piston the combustible mixture in the power cylinder 9 is ignited and the power piston I therein is driven through its power stroke, the valves associated with this cylinder remaining closed, while the inlet valve Me to the power cylinder 9a opens to admit pressurized cooled fluid from the tank 6 to the power cylinder 9a. At this time both valves 53 and 53a which control communication through passageways 54 and 54a remain closed while valves 55 open so that exhaust gases are discharged from expansion cylinder [2 by the piston i" which at the time is moving through its exhaust stroke.

In the last stroke in the cycle of operation of the power piston la all of the valves associated with its cylinder 5a remain closed so that the fluid previously introduced into this cylinder is compressed. At the same time the intake valve M associated with power cylinder 9 remains closed While the valve 53 associated with this cylinder opens so that exhaust gases in this power cylinder are discharged into the expansion cylinder '12, the piston I" in this cylinder at this time moving through its suction stroke and the valves associated with this cylinder being closed.

This completes the description of one cycle of operation of each power cylinder, from which it will be seen that the expansion piston i completes two cycles for each cycle of the power pistons and la.

To provide air compressed to the right pressure for scavenging the power cylinders 9, a secnd: compressor cylinder Ila is provided in which a piston 10a is reciprocable, this piston preferably being driven by the previously mentioned crank shaft 24. It will be noted in Fig. 1 that the two compressor pistons TI) and Illa are 180 degrees out of phase relative to each other and displaced 90 degrees relative to the power pistons I and In and compressor piston I. Upon the suction stroke of the piston ma, air is drawn through a, passageway I into the compressor cylinder IIa, a suitable inlet valve 82 being provided in this passageway. The compression chamber Ila is provided with the conventional inlet and exhaust valves 56a and 5111, respectively. Air under pressure is discharged from the cylinder Ila upon the discharge stroke of the piston tea in this cylinder past av suitable check valve 83 in a duct. I9 (Fig. 3) and into a tank or reservoir ll; secured on one side of the engine block. Preferably this reservoir is cooled as is reservoir 5 by a conventional water cooling or other cooling system I2.

A duct 84 connects the reservoir 11 to inlet valves I4 and Ida in the head of the driving cylinders 9 and 9a. These valves may be of conven: tional construction not shown and are driven from the engine in timed relation to the movement of the power pistons l but so that they open for only a short interval just prior to the time that the exhaust strokes of the power pistons I and Id end.

The volume of the reservior 17 relative to the volume of the cylinder IIa supplying air there to and the volume of the power cylinders 9 and 9a when the power pistons I and la approach the upper end of their stroke is such that the pressure of the air in reservoir I? is always higher than the pressure of the inert gases in the upper end of either of the power cylinders 53 and 9a during the time the inlet valves 1s, I ia are open. Furthermore, the volume of air which may be delivered to either of the power cylinders is above the volume of the upper ends of these cylinders. Thus, the compressed air admitted through the inlet valves I4 and Me scavenges the warm and inert exhaust gases from the upper ends of the power cylinders 9 and 9a causing these gases to be discharged past valves 53 and 53a into expansion cylinder I2. At the same time the ends of the pistons I and Id are cooled by this air.

It will thus be seen that there has been provided an improved engine in which compression of the operating fluids is performed in stages with the final compression occurring in the cylinder which forms the combustion or explosion chamber. Furthermore, these fluids are cooled between stages of compression so that they are cool when admitted to the combustion chamber and therefore may be compressed to a higher degree than if they were warm. Another advantage arising from the cooling of the operating fluid between the stages in its compression is the fact that this fluid may be used to cool the power pistons in its passage from the accumulator tank 5 to the tank 6.

In accordance with another feature of the inconnecting structure. which may be provided.

This difi'icultyis avoided in the modified engine disclosed in Figs. 4 to 8 by arranging the power and compressor pistons in tandem or axial alignment. The connecting rods are connected to the compressor pistons in these piston assemblies and since these compressor pistons are of larger size than the power pistons, room is present for a.

connection of the desired .sturdiness.

In Figs. 4 to 8, the same or similar parts will be referred to by the samev reference characters used to identify those parts in describing Figs. 1 to 3.

Referring to Figs. 4 and 5,. it will be. seen that the modified engine has a block: Iilllin which a. plurality of axially aligned variable diameter.

first and second cylinders I82, IilZ-a and I 02" and IIJI, m ld and I0!" respectively, are formed, separated by partitions I04. Power pistons I and Id are reciprocable in the cylinders m1, lid and are connected by rigid links I05 and Idea, respectively, passing through partitions IM- to compressor pistons I03, Iota which, are reciprocable in the cylinders m2, IBM from tubes H2. The lowermost ends I29, IZt-a, I28" of the pistons I. Ia and I" reciprocate in the lower end. of: cylinders InI, 1cm. ml" and operate as compresso in these cylinders.

Air is admitted to the cylinder IE2, iromtubes II2, through ports MI in the side walls. thereof. Cylinders H3211, H32" also have similar ports, such as ports III, leading to tubes H2. Discharge of air from these cylinders to an accumulator tank or reservoir III'I, which is divided by partitions I 2| into a central compartment I23 and end compartments I24, I24a, is controlled by a rotary valve 22 (Figs. 4 and 8) mounted upon a shaft II driven from the engine by any suitable means not shown in timed relation to the movement of the pistons. This valve rotates in a water jacketed chamber and has passageways adapted upon rotation of the valve to be brought into communi cation with passageways in the partition members IIM communicating with the upper ends of the cylinders I02, IIlZa, I92" and with the lower ends of the cylinders IDI, IIlI'a, IIJI".

In general an engine having its power and compressor pistons arranged in tandem may be organized to operate in much the same manner as the engine previously described. The compressor pistons in the compressor cylinders compress the operative fluid in stages and this fluid is cooled at an intermediate stage or stages in an accumulator tank 5. From this tank it flows through diametrically opposite ports 8 and 8a in the walls of the cylinders Illl, IIJIa and ID! to an accumulator tank 6 when diametrically opposite ports I and Ta in the power pistons I and Ia are brought into register with the ports 8 and to by reciprocation of the pistons I, Ia or it may be discharged directly to the atmosphere through ducts H3 and H311 as described hcreinafter. The cooled fluid flowing through the hollow power pistons I, la cools the same and the heat picked up by this fluid is extracted when it flows into the accumulator tank 5. From, the tank 6 the fluid may flow through conduits l3. and I 311 to the chambers of inlet valves I I and I 404 in the head of cylinder IBI, IIIIa for admission to the working cylinder.

Thus in the engines illustrated in Figs. 4 to 7, the fluids required for the feed, for the cooling of the piston and for the scavenging of the waste gases are compressed by the compressors I83, Inca and I03" and I20, mm and I28" to create a circulation of the various fluids through the accumulator tanks and through all the pistons I and la to the upper ends of the cylinders IOI and Illla which serve as combustion or explosion chambers.

For the collection and cooling of the fluids discharged by the compressors I 03, MM and I93". 9. third accumulator tank Iill (Fig. 4) is provided and is cooled by liquid circulation or other suitable conventional means. As this tank is connected to the adjustment member or valve 22 of which it closes the ports, these last are cleared by straight ducts H (Fig. 4) or ducts Hi8 bent upwards allowing the fluids an airtight passage through the tank. A tubing I99 bent downwards allows ultimately certain of the compressors I20, I2Ila and I28 to draw precompressed and cooled fluid for the combustion or explosion chambers from the bottom of accumulator tank I01. As explained previously, the tank I81 is divided into airtight compartments by vertical partitions I2l, I2ia and the compartment I23 may act as a scavenging air storage tank, storing up the compressed fluid required for the scavenging of the waste gases while compartments lied, I241: supply the compressors I28, IZIla and I253".

As previously explained, a discharge duct II3 (Fig. 4) in the accumulator tank 6 may if desired be arranged as an extension of the intercommunication ports 8 and 8a to allow the direct discharge into the atmosphere of the fluid which has been used to cool the power pistons I and Ia.

In that case the tubing I3 and 13a connects the lower end of the accumulator tank 6 or its compartment I22 with the chambers of inlet valves I4 and Ma of the engine cylinders and conveys cooled fluid to the inlet valve chambers.

A tubing I I4 may connect the lower end or the scavenging air chamber 923 of the accumulator tank I01, to the chambers of the scavenging air inlet valves I l and I ia carried in the head of the engine cylinders lcl and It! a. The valves (4 and 14a are timed to be open for a short interval just prior to the time that the exhaust strokes of the power pistons I and la end. Tubing H interconnects the end compartments of the accumulator tank 5, which is divided by the partitions In, to balance pressures in these compartments. Tubing H6 connects the distributor valve 22 with the central compartment of the accumulator tank 5.

While the principle of operation of the engine shown in Figs. 4 to 8 is similar to that of the en gine shown in Figs. 1 to 3, a brief explanation follows, in which the compressors and explosion chambers are designated by letters, for purposes of clarity. The combustible mixture from the conduits II2 enters the compressor chambers E through the ports II I. The mixture is compressed and flows through the valve 22 into the end compartments I24 of the tank lift, from which it is withdrawn by the conduits El and distributing valve 22 into the compressor chambers C of the compressors I28. The combustible mixture is compressed for the second time and is expelled through the distributor valve 22, pas- .sageway 2 I, and conduit I06, into the cooling accumulator tank 5, from whence it flows through the pistons I and Ia to the accumulator tank 6 when ports I and 8 are aligned. The cooled combustible mixture from the tank 6 is admitted through the ducts I3 and |3a and inlet valves I4 and I la to the cylinder chambers A. The burned and partially expanded gases are admitted to the expansion chamber B and then exhausted to the atmosphere.

Cooling of the expansion chamber piston I" is insured by air taken in through the ducts H0 and distributor valve 22 to the compressor chamber G. Compressed air flows through the valve 22 and the ducts I I6 to the central compartment of the tank 5 and then through the aligned ports I and 8 in the piston I" and cylinder I2 to be exhausted through the duct H3.

scavenging air is taken into the compressor chamber F through the port IN, is compressed, and is sent through the valve 22 to the central compartment I23 of the cooling tank It". It is cooled and flows through the conduits H4 and valves is and Ma into the driving cylinder chambers A to scavenge the burned gases into the expansion chamber B.

Having thus described my invention, what I claim as new and useful and desire to secure by Letters Patent of the United States is:

1. In an internal combustion engine, a plurality of power cylinders, pistons in said power cylinders, an expansion cylinder adapted to receive exhaust gases from said power cylinders on the exhaust stroke of the pistons in said latter cylinders for further expanding said gases, a plurality of compression cylinders, a compression piston in each of said compression cylinders, a first cooling accumulator receiving fluid discharged from at least one of said compression cylinders, a second cooling accumulator, means for conveying fluid under pressure from said first accumulator to said second accumulator including ports through said power and expansion cylinders and pistons adapted to register for the flow of fluid therethrough for a portion only of the stroke of said pistons, a third cooling accumulator receiving air under pressure discharged from at least another of said compression cylinders, and means for establishing communication between said third accumulator and the inlet end of said power cylinders including means to admit cooled air to the cylinders for scavenging purposes and to cool said power pistons.

2. In a four cycle compound combustion engine, two piston operated fluid compressors, a cooling accumulator tank for receiving the fluid delivered by said compressors, two power cylinders, inlet valve means for said power cylinders, power pistons in said power cylinders, a relief cylinder for expanding the exhaust gases from said power cylinders, a piston in said relief cylinder, said pistons in said power and relief cylinders being hollow and said power and relief cylinders and pistons having apertures adapted to register during the reciprocation of said pistons, conduit forming means for connecting said compressorfed fluid cooling tank with, the first of said power cylinders, said relief cylinder and the other of said power cylinders to establish a flow of cooled fluid through the said hollow pistons when said apertures register, outlet conduits adapted to recover the fluid heated in its passage through said pistons, cooling tanks into which said outlet conduits are adapted to discharge said heated fluid, and a pipe system for feeding cooled fluid to the inlet valve means for said power cylinders alternately to provide a constituent of an operating fluid for said power cylinders and to scavenge the inert exhaust gases from the power cylinders.

3. In a compound combustion engine, two twocycle piston operated fluid compressors, a cooling accumulator tank for receiving the fiuid delivered by said compressors, two power cylinders, inlet valves for said power cylinders, four cycle pistons in said power cylinders, a relief cylinder for expanding the exhaust gases from said power cylinders, a two cycle piston in said relief cylinder, said pistons in said power and relief cylinders being hollow and having diametrically opposite apertures and said power and relief cylinders having apertures adapted to register with the apertures of the respective hollow pistons in said cylinders during the reciprocation of said pistons, conduit forming means for connecting said compressor-fed fluid cooling tank with, the first of said power cylinders, said relief cylinder and the other of said power cylinders to establish a flow of cooled fluid through said hollow pistons, outlet conduits adapted to recover the fluid heated in its passages through said cylinders and pistons, cooling tanks into which said outlet conduits are adapted to discharge said heated fluid, a pipe system for feeding the cooled fluid from said cooling tanks to the inlet valves of said power cylinders, a third compressor, an auxiliary tank adapted to receive the air delivered by said third compressor together with means for utilizing this air for scavenging the burned gases from said power cylinders.

4. In an internal combustion engine, a plurality of power cylinders, pistons in said power cylinders, an expansion cylinder adapted to receive exhaust gases from said power cylinders on the exhaust stroke of the pistons in said latter cylinders for further expanding said gases, a plurality of compression cylinders, a compression piston in each of said compression cylinders, said power cylinders each being arranged in tandem with compression cylinders, 21. first accumulator receiving fluid discharged from one or more compression cylinders, a second accumulator, means for conveying fluid under pressure from said first accumulator to said second accumulator including ports through said power and expansion cylinders and pistons in register for the flow of fluid therethrough for a portion only of the stroke of said pistons, a third accumulator receiving air under pressure discharged from one or more compression cylinders, means for establishing communication between said third accumulator and the inlet end of said power cylinders including means to admit air to the power cylinders for scavenging purposes, a common crank shaft for said pistons, and means for establishing communication between said first and third accumulators and predetermined compression cylinders including a distributing valve operated by said engine, said valve also controlling the flow of fluid to and from the compression cylinders supplying said first accumulator.

5. An internal combustion engine as defined in claim 4, wherein each of said power cylinders is arranged in tandem with first and second compression cylinders and wherein interconnected pistons are provided in said cylinders, including a double acting piston having one side constituting a power piston and its opposite side constituting a first compression piston, and wherein a second compression piston is provided connected to said double acting piston and to said crank shaft.

ALBERT NACCACI-IE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PA'I'ENTS Number Name Date 740,711 Sutton Oct. 6, 1903 967,828 Pierson Aug. 16, 1910 1,347,087 Gernandt July 20, 1920 1,431,547 Smith Oct. 10, 1922 1,844,109 Speer Feb. 9, 1932 1,904,871 Lindberg Apr. 18, 1933 2,242,538 Naccache May 20, 1941 2,325,032 Biichi July 27, 1943 FOREIGN PATENTS Number Country Date 17,961 Great Britain Aug. 18, 1904 309,009 Great Britain Apr. 2, 1929 680,374 France Jan. 18, 1930

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