US2059802A

US2059802A - Engine

Info

Publication number: US2059802A
Application number: US667096A
Authority: US
Inventors: William F Logan
Original assignee: LOGAN NEWVILLE MOTORS Inc
Current assignee: LOGAN NEWVILLE MOTORS Inc; LOGAN-NEWVILLE MOTORS Inc
Priority date: 1933-04-20
Filing date: 1933-04-20
Publication date: 1936-11-03
Anticipated expiration: 1953-11-03
Also published as: DE639863C; GB434612A; FR771485A

Description

Nov. 3, 1936.

W. F. LOGAN ENGINE Filed April 20, 1933 ill l'o: a4

Nov. 3, 1936. w. F, LOGAN 2,059,802

ENGINE Filed April 20; 1933 6 Sheets-Sheet 2 IlliilH mgg llllilll?! 114 w v 3mm Nov. 3, 1936. w. F. LOGAN I 2,059,802

' ENGINE Filed April 20, 1933 6 Sheets-Sheet 3 Nov. 3, 1936. w LOGAN 2,059,802

ENGINE Filed April 20, 1933 6 Sheets-Sheet 4 i v 747 5 u Gum/M1 3 Nov. 3, 1936. I w LOGAN 2,059,802

ENGINE Filed April 20, 1955 e Sheets-Sheet 5 IN VENT OR ami/m ATTORNEYS Nov. 3, 1936. w LOGAN v 2,059,802

ENGINE Filed April 20, 1933 6 Sheets-Sheet 6 Patented Nov. 3, 1936' UNITED STATES PATENT OFFICE ENGINE Application April 20, 1933, Serial No. 667.0%

Y 29 Claims.

This invention relates -to engines, and more particularly to engines of the type employin what are known as floating pistons. While in its broader aspects the invention has utility when applied to steam and air e gines, the invention is of particular utility w en embodied in an internal combustion engine, and it will therefore be more particularly described with reference to such use. The present application is a continuation in part of my application Serial No. 580,176, filed December 10, 1931, entitled Gas engines, and of my application Serial No. 498,189, filed November 25, 1930, entitled Gas engines.

. It is an object of this invention to provide a energy of a moving column of substantially incompressible liquid and the potential energy of an elastic means under conditions which permit the development and use of said energy with high efliciency. 1

Another object of this invention is to provide an engine of the type just characterized wherein form delivery of power and wherein vibrations and irregularities of operation eliminated.

Another object of the present invention is to provide an engine of the type first characterized wherein the delivery of power is under the control of parts whose speed is regulated independently of any fluctuations in speed of the floating 0 piston during its power stroke. Y

Another object of this invention is to provide an internal combustionengine of the type employing afloating piston wherein the compression of the fuel mixture and the time of its ignition as wel1 as its admission to and discharge from the. combustion chamber are controlled independently of fluctuations in speed of the floating piston during its combustion stroke.

Another object of this invention is to provide an engine of the type first characterized which are substantially the delivery of the kinetic and potential energy avoids the tendency of the floating piston to rebound at the end of its power stroke.-

Another object of this invention is to provide an engine of the type employing a floating piston wherein the use of a crank mechanism is avoided and wherein power is delivered to the driving shaft substantially at right angles thereto at all times.

Another object of this invention is to provide an engine of the type employing a floating piston which avoids the conditions consequent on the occurrences of dead centers,and which avoids irregularities of speed, vibrations, shocks, jars and the like. 1

Another object of this invention is to provide a novel internal combustion engine wherein compression of the fuel mixture after ignition with the resultant energy losses is entirely avoided.

Another object of this invention is to provide a novel internal combustion engine which enablesthe cylinder clearance to be materially reduced with substantial increase in efficiency.

Another object of this invention is to provide a novel internal combustion engine wherein it is practicable to furnish each charge of fuel with such a. quantity oi. oxygen as will obtain substantially a complete combustion of said fuel in the combustion chamber with the resultant elimination of fuel losses.

Another object of this invention is to provide a novel engine which enables the production of high power at relatively low speed or high speed at relatively low R. P. M. at the engine.

Another object of this invention "is to provide a'novel engine in which there is a substantially smooth and" uniform delivery of power to the driving shaft throughout the operation of the same.

Another object of this invention is to provide a novel engine which facilitates close regulation 'of the speed and delivery of power and which also provides flexibility of design in securing desired rates of power delivery and desired rates of revolution through a wide range.

Another object of this invention is to provide a novel engine whereby increased power per unit of fuel consumed and increased thermal efliciency can beobtained.

Another. object of the present invention'is to provide a novel engine wherein the heat losses are so reduced that a cooling system is generally unnecessary, although one may be used if preferred.

Another object of this a novel internal combustion engine which enables V 60 I ment.

the maintenance normally of a constant air and fuel mixture irrespective of variations of load on the engine, but which also enables variations of mixture for variations of load or speed'if preferred.

Another object of this invention is to provide a novel internal combustion engine wherein a low exhaust temperature and pressure can be obtained and also efllcient scavenging of each combustion chamber effected.

Another object of this invention is to provide a novel engine which has low weight per unit of power delivered and which therefore readily lends itself to use in airplanes, automobiles and the like.

Another object of this invention is to provide a novel engine which is simple in construction, strong and rugged in service, and economical in operation and maintenance, and which readfly lends itself to a wide range of control and use.

Another object-of this'invention is to provide a novel method for controlling and utilizing the energy developed by a floating piston.

Other. objects will appear as the description of the invention proceeds.

The invention is capable of receiving a variety of mechanical expressions, two of which are illustrated on the accompanying drawings, but it is to be expressly understood that the drawings are for purposes of illustration only, and are not to be construed as a definition of the limitsof the invention, reference being had to the appended claims for that purpose.

Referring in detail to the drawings, what the same reference characters are employed to indicate corresponding parts in the several figuresr I Fig. 1 is an elevation of a preferred embodiment of the present invention;

Fig. 2 is a side elevation of the embodiment of F Fig. 3 is a front elevation on a smaller scale of another embodiment of the present invention;

Fig. 4 is a longitudinal section through the embodiment of Fig. 3 on a slightly enlarged scale;

Fig. 5 is a vertical section, on a still further enlarged scale, taken on the line 5-5 of Fig.4;

Fig. 6 is a detailed sectional view of one of the mechanically operated by-pass valves;

Fig. 'I. is a somewhat schematic view illustrating another arrangement and location of the valves;

' Fig. 8 is a detail of thestop for each piston' unit as used in the embodiment of Figs. 1 and 2; Fig. 9 is a sectional view of the embodiment shown in Fig. 1; f

Fig. 1 0 is a somewhat schematic viewillustrating an arrangement and location of the valves, and

Fig. His 9. vertical section of another embodi Referring first to the embodiment illustrated in Figs. 3 to 6, inclusive, and particularly to Fig. 4, a base section I II, of any suitable size and construction, is mounted on any suitable foundation or frame'and provides a receptacle or tank. Suitably mounted above said receptacle I0 is a cylinder block ll, here shown as including two cylinders l2 providing combustion chambers, but it is to be expressly understood that the invention is not restricted to the use of only two cylinders as willhereinafter appear. As shown, a shaft housing I 3 is interposed between receptacle II and cylinder block ll andis suitably secured to each.

as by bolts, screws, welding, etc.,' at the flanges H and ii. The cylinder block I I is provided with a suitable head 18 attached to the body thereof in any suitable way and in the form shown a water jacket ll isprovided for the cylinders and ders I2 providing combustion chambers, and I hence here shown as two. Said cylinders 2| communicate with and are here shown as projecting into'th'e interior of the tank It, and suitably mounted on the bottom of said tank II are valves 23 which normally close the bottom of thecylinders 2|. Said valves may be of any suitable construction and as hereinafter'pointed out in con junction with the embodiment of Fig. 1 preferably take the form of elastic balls, but as here shown, the valves arein the form of disks provided with stems 24 which are reciprocably mounted in spiders 25 formed on or attached to the bottom memberll. If-desired s'aid spiders may be mounted on removable plates 26 suitably secured over openings in the bottom member 22,

said openings being suflloiently large to permit the withdrawal of the spiders with the valve members moimted thereon. Said removable plates 28 may be secured in pomtion in any suitabl way. as by bolts through flanges 21 means, however, may be provided for' gaining access to the valves. Each valve 13 is normally -with interposed gaskets 28. Any other suitable urged into its position for closing the bottom of its opposed cylinder 2!, and to this end, a helical spring 29 surrounds each valve stem u and reacts between the spider 25 and the valvedisk 23 to normally urge the latter into its seating position.

Although it is possible to operatethe engine using a compressed gas in the tank above described, it ispreferredto use a liquid subjected to the pressure of an elastic medium because of the relative incompressibility of liquid. Tank I0 is accordingly partly filled with a liquid 3|, such as oil, the volume of liquid therein being sumcient to assure that under no conditions of operation will the lower open ends of the cylinders II be uncovered. Saidliquid may be introduced into j the tank ll through any suitable filling opening, and'a drain opening is indicated at 3|. 000pcrating with the surface of the liquid as, either directly or through an interposed plate or plunger as hereinafter explained, .is an elastic medium which is under a substantial initial compressionand which, may be further compremed when liquid is forced from the cylinders 2| into the tank- IO. Said medium thereby acts as a storer of potential energy and subsequently delivers said stored energy as hereinafter explained. While said elastic medium may take the form of springs or equivalent elements, the preferred elastic medium is a gas, such as air fllling' the space 32. Said air is under a substantial initialpressure.

and may be introduced through any suitable pipe as 33. The initial pressure of the air employed The interior ofsaid tank It is in communi- 75 cation with the cylinders 2|, and the connections therebetween may take a variety of forms. As here shown, a by-pass conduit 35 of any suitable construction, shown as a pipe which leads to the interior of each cyinder 2| adjacent the lower end thereof, projects to the exterior of the tank, through suitable fluid-tight joints, as shown in Fig. 3. Pipe 35 also communicates with the interior of thetank ID at a point below the surface of the liquid therein, sufliciently below the minimum liquid level so that its inlet will never be uncovered by said liquid under any condition of operation. As here shown a pipe section 36 leads from said conduit 35 and opens into the tank at 38 adjacent the bottom thereof. Said by-pass conduit 35 is provided with a valve mechanism 39 for each cylinder as hereinafter explained, said valve mechanism as shown being disposed exterlorly of the tank, but the valves as well as the connections orconduits between the tank and work cylinders may be within the tank as will hereinafter appear. I

Cylinder block ii, in addition to the two cylinders l2 providing combustion chambers 40, includes a pair of cylinders 4| providing compression chambers, although as hereinafter explained in conjunction with the embodiment of Fig. 1, a

single compression chamber can be used for both cylinders l2, or compression chambers may be formed within the cylinders l2 below the pistons thereof or within the cylinders 2| above the pistons thereof. Each cylinder i2 is substantially in alignment with a cylinder 2!, and in the form here shown the cylinders l2 and 4! are also arranged in longitudinal alignment, but this is not essential, as the cylinders l2 and M may be otherwise arranged and the compression cylinders 4i may if preferred be disposed laterally with respect to the cylinders l2.

Eachcylinder i2 is provided with a piston 42 which is connected through a piston rod 43 of any suitable size and construction with a piston M disposed in the associated cylinder 2i, or a single cylinder and piston combining the functions of cylinders i2 andfil and pistons '42 and 54 could be used. In the form here shown (see Fig. 5) piston rod 63 is provided with an offset a to pass around the driving shaft 46, but as shown in the embodiments of Figs. 1 and 2, the driving shaft may be disposed laterally with respect to the piston rods lt so that the latter may extend in right lines. The driving connection from each piston rod t3 to'the driving shaft 65 is such that there is a right angle delivery of power from the piston rod'to the driving shaft throughout the work stroke, and as. the present invention employs pistons which are to float when moving under the expansion due to combustion of the fuel mixture, the construction is such that during the stroke of each piston pair, iii and id,

under the propulsion due to the combustion of -ates with a segmental gear48 that has teeth for slightly over 180, so that there is at least one tooth more than 180 of teeth for a purpose hereinafter explainedr- Said segmental gears 48 are suitably secured to the shaft 46, and each gear is so disposed that their teeth mesh with the corresponding rack 41 only during the up stroke of the piston pair, while during the down stroke of the piston pair the cutaway portion of the segmental gear is opposed to the rack 41, or the segmental'gear may be constantly in mesh with the rack and a one way clutch be interposed between the gear and the shaft. The diameter of the gears 48 is selected to eifect the desired lever ratio suitable for the particular length of stroke and timing employed.

Each compressor cylinder 4 I' is provided with a piston 50 driven from the driving shaft 46 in any .suitable way, here shown as through a piston rod 5| and crank 52. Compressor 4| may operate to compress only the air to support the combustion of the fuel, after which the fuel may be in-' jected into the compressed air, as by an injector of any suitable construction, opening for example into the combustion chamber, or the fuel as well as the air may be mixed in the compressor and subjected to compression in advance of introduction into the combustion chamber. The compressed air from the compressor may be introduced after the piston 42 has made its scavenging stroke or the air may be introduced to help purge the combustion chamber of burnt gases. The fuel used may be either gaseous or liquid introduced into each compressor from any suitable carbureting device 53. Each compressor is provided with a suitable inlet valve 54 and outlet valve 55, and each cylinder is also provided with a suitable inlet valve 56 and outlet valve 51. Said inlet and outlet valves are operated in any suitable way in timed relation with the movement of. the pistons, and as here shown said valves are tappet valves operated by rocker arms 58 suitably pivoted on brackets 59 and in turn operated by rods 60 and rocker arms 6| suitably pivoted on brackets 62. Rocker arms iii are operated from cams 63 mounted on a cam shaft 64 driven in any suitable way as by a chain drive 66 from the driving shaft 6. .It will be understood] that the cranks b2 and earns 63 are so constructed and arranged as to effect the intherein, the transfero-f the charge to the combustion chambers 48, and the exhaust of the .burnt gases from said combustion chambers in proper timed sequence with the operation of the parts to effect the cycle of operation herein=- after explained.

As before noted each cylinder 2i is provided, in the by-pass conduit 35 associated therewith, with a suitable valve mechanism 39 for opening and closing communication between said by-pass and the interior of said cylinder. Said valve mechanism may be ofany suitable construction and operated in any suitable way from the driving shaft or cam shaft. As here shown, theconduit leading from each cylinder 2i has a valve housing .10 which, as shown in the enlarged detail of Fig; 6, contains a butterfly valve disk "II operable or solid. As here shown a liquid fuel isv by a crank arm 12 disposed. exteriorly of the housing 10 and mounted on the pivotal axis l3 46. Said cams are so arranged "as to effect the operation of the valves H in the timed sequence hereinafter described. By-pass 35 is also preferably provided with a suitable valve '|8 whereby the size of thepassage for fluid flow may be varied; 'I'his'valve may be manually or automatically operated.

Any suitable means are provided forigniting the fuel mixture in the combustion chambers 40, spark plugs 80 being diagrammatically indicated and controlled through a distributor III of any suitable character and construction driven from drivingshaft 46. Driving shaft 46 is also shown as provided with a pulley 82 as indicative of any suitable driving connection from said shaft 46 to the means to be driven, or a flywheel may be pro-' vided if desired.

The cycle of operation of the engine is as follows: The fuel mixture, or the air alone if a fuel injector is used, is drawn into a compressor 4| and compressed therein, and the charge is then transferred to a combustion chamber 40. Compressor 4| is of such size that a suflicient quantity of air is drawn thereintoto effect a substantially complete combustion of the fuel, whether gaseous or liquid and whether introduced into the compressor or into the combustion chamber itself, When the piston 42 has reached the top of its stroke and after'the fuel mixture is introduced into the combustion chamber, said mixture is ignited. As said ignition occurs only after the piston 42 has reached its uppermost position, there is no compression of the mixture after ignition, and therefore the entire force of expansion arising fromthe combustion of the fuel mixture is directly applied to the piston 42. Piston 42 being a floating piston, it is forced downwardly at precisely the rate at which expansion of the mixture occurs under combustion, it being remembered that during this stroke of piston 42 there is no mechanical connection between the piston' and .the driving shaft. Hence there is no mechanical restraint upon said piston to cause the normal expansion of the mixture under combustion to be retarded, and therefore the tendency for the energy to be dissipated in heat to the engine walls is materially reduced. Moreover, as there is no compression of the mixture after combustion starts, the heat losses characteristic of the compression of ignited charges is avoided. Also, as the amount of air initially provided is sumcient for complete oxidation of the fuel, the heat losses incident to delayed burning of the gases are largely avoided. In other words, the piston is free to move at the variable rate at which the mixture tends to expand naturally when combustion is free and complete.

The movement so imparted to piston 42 by the expanding gases in the combustion chamber 40 is transmitted through piston rod 43 to the associated piston '44 in cylinder 2|. As soon as the pressure per square inch on piston 44 is sufilcient to overcome the pressure per square inch of the compressed air on the oil 30, valve 23 is opened and the .oil is driven from the cylinder 2| by the advancing piston, the entire end of the 'cylinder being preferably open so as to offer the minimum resistance to the flow of the oil. If the piston in the other work cylinder were held against move.-

ment, or if the invention be embodied in asingle cylinder engine, this displacement of oil from the cylinder 2| to the tank In is converted intopotential energy in the form of an additional com- *pression of the gas in the space 32. As a matter Ill into a second cylinder 2|. Simultaneously with or immediately after the initiation of the combustion stroke of the piston 42," the butterfly V valve 12 for the opposite cylinder 2| is opened and the oil flows into said cylinder 2| to move the cor der 2| is at a varying rate, however, because of the'varying rate of movement of the piston in the combustion chamber, there is the development of both' potential energy in the compressed gas and kinetic energy in the flowing oil, the former conserving the energy that would otherwise be lost if there were a controlled rate of development of pressure on the oil in the first cylinder 2|. In other words substantially all of the energy developed by the expansion of the fuel mixture under combustion and the inertia of the moving pistons is captured by the moving oil and compressed gas in the tank, the latter acting as a reservoir for the energy developed in excess of the controlled rate of output through the oil and delivering said stored energy to maintain a uniform rate of output throughout the work stroke. But the piston 44 makes its work stroke at a substantially uniform pressure, because the actual variation in pressure in the compressed gas in the tank I0 is in fact relatively small.

During this work stroke of the piston 44 the nected to the piston 44 that is making the work stroke is at this time scavenging its corresponding combustion chamber 40, and as the next charge is being compressed in the chamber of the associated compressor 4| it is possible to hold the outlet valve of said combustion chamber open for a major portion of the stroke'and effect a satisfactory scavenging of the combustion chamber. During this same stroke the compressor piston 50 is making its compression stroke, its suction stroke having been made during the work stroke of the piston 44 first referred to, and as the working piston 44 approaches the end of its stroke, the outlet valve from the corresponding combustion chamber is closed and the inlet valve.opened, while the outlet valve. from the associated compressor chamber is opened simultaneously so'that the compressed charge is transferred to the combustion chamber last referred to. when thispiston 42 reaches the top of its stroke, the charge is ignited and the cycle is repeated, the 011 now being driven from the second" cylinder. 2| into the tank I at the rate determined by the floating piston 42 in the combustion chamber, while the first referred to piston 44 is new performing its work stroke, and its assoa ciated piston 42 is scavenging its combustion.

chamber. 40, and the related compressor 4| is simultaneously making its compression stroke.- It will be understood that the two piston pairs 42 and 44 have their phases 180 apart.'

As each segmental gear 48 extends for one or more teeth beyond 180 a driving relation is established between the first tooth of the second segmental gear to go into operation and its rack before the last tooth of the segmental gear that has been performing a work stroke becomes disengaged from its rack. Hence there is no' intertion between the successively acting racks and the driving shaft, and the output of power is therefore smooth and continuous.

From the foregoing description the preferred embodiment of Figs. 1, 2, and 9 will be understood from a brief reference to the differences thereof from the embodiment of Figs. 3 to 6, corresponding parts being given the same reference characters as in the embodiments of Figs. 3 to 6. The embodiment of Figs. 1, 2, and 9 as shown has its tank or receptacle section III sub-divided into a base portion III) and an upper portion III, said two portions being suitably united as by bolts passing through flanges II2. Base portion IIII may be mounted on any suitable foundation II3 as by bolts II4. The provision of the joint at IIZ permits the upper part of the engine to be lifted with respect to the lower portion III] for access to the bottom of the tank and the valves therein, etc. If preferred, however, the tank may be made in one piece or in any other desired combination of sections. The portion III in this embodiment also includes the portion of the casing which houses the driving shaft and associated parts.

In place of disk valves 23 within the tank, the

I present invention employs spherical valves I23 mounted on coil springs I29. Said valves are preferably constructed of an elastic medium and constitute elastic balls that may give in the event that an undue pressure is imparted thereto.

In this embodiment the oil space within the tank I0 is separated from the compressed gas space therein by a plunger I35, the cylinders 2| in this embodiment having intermediate the same a centrally disposed cylinder I36 which opens at its botttom into the oil space I31 and has above the plunger I85 a space I38 for the compressed gas. Therefore, even though the engine be turned upside down, as may occur in use on an airplane, the oil in the space I31 cannot uncover the bottoms of the cylinders 2i and the inlets to the by-pass 35. It may here be noted that so long as the operating fluid is maintained in sealed contact with the pistons 44 it is unnecessary that saidpistons work in or even project into the tank I8.

In this embodiment a single compressor 4I is provided, withsuitable' connections and valves for supplying compressed charges to the two combustion chambers 40, and the driving shaft 46, which is so positioned as'to avoid any offset in the piston rods, is provided with a beveled gear I 48 which meshes with a beveled gear I4I of one half the diameter'of gear I40 on a stub-shaft I42 that carries an eccentric I45 for driving the piston 50 of said compressor. The outlet valve I54 of the compressor controls the admission of the compressed fluid into a storage space I55 which communicates with one or the other of the combustion chambers when one or the other of the inlet valves I55 of the latter is opened. As the com- This embodiment also eliminates a separatecam shaft, all of the cams for operating the inlet andoutlet valves being mounted directly on the driving shaft 48 as shown at I59. Likewise the injector being generally indicated at I85 and communicating. with any suitable source of fuel. As shown in the fragmentary view of Fig. 8, each of the work pistons 44 may be provided with a cushioning or stop device in the event that the piston tends to move too far on its working stroke. As here shown each work piston '44 has mounted above and resiliently spaced from the same a stop member I45 which has an axially extending rim- I46. The end of the cylinder is provided with an overhanging and inwardly directed rim member I4'I spaced from the wall of the cylinder sufficiently to provide an annular recess that will receive the rim I 46 and cooperate therewith to form,

in effect a dashpot. Stop member I45 is normally spaced from the piston proper 44 by a coil spring I48. A suitable gland may be provided around the piston rod as shown. at I49.

Ifthe piston 44 tends to overtravel the rim I45 will enter the annular space between the cylinder wall and the rim I41, acting as a dashpot and bringing stop member I45 to rest, while the spring I48, as member I45 is. retarded, will oppose resiliently the relative approach of piston 44, but

yielding until the piston is stopped. Hence the combined dashpot and spring action will bring the piston 44 to rest at the end of its stroke without shock or jar.

It is also preferred to provide means whereby any oil leaking past the piston 44 will be returned to the tank. As here shown the upper end of the piston 44 is recessed, and the body of the stop member I45 is so shaped as generally to conform and mate with said recess. At the bottom of said recess one or more check valves I5I control passages I52 in the piston, said valves being normally held closed by springs I53 as well as by the pressure existing at the under side of the piston. If oil should escape past the piston, however, it will flow into the recess I58 and collect therein. When the stop member I45 is arrested by the engagement of its rim I45 within the rim I41 and piston 44 continues to move against the tension of the spring I48, any oil trapped in recess I5I] will be placed under suflicient pressure by the relative movement of the recess in the piston and the stop member to force the valve orval'ves I5I toopen and return the oil to the interior of the tank. A suitable valve controlled passage may be similarly provided whereby the pressure of the air in the tank may be maintained atthe desired value by the action of the piston and stop member.

Otherwise the construction and manner of operation will be apparent from the more detailed explanation of the embodiment of Figs. 3 to 6.

Fig. 7 illustrates an arrangement wherein the passages of communication between the tanks and work cylinders as well as the valves for con trolling the same are disposedinside of the tank. As here shown, each work cylinder communicates with the tank I0 through a short passage I60 formed in the wall of the cylinder, thus eliminating the friction incident to the use of long pas- 75 sages. The by-pass valves are also now located in the tank, and may take any suitable form.

, within the cup is forced away from stop I 16 and further into cup closure of said orifice. Arm I16 is rotatably 'place of the separate adjustable valves 18 for varying the size of the by-pass in the embodiments of Figs. 1 to 6, lever i63 carries a pair of wedge-like stops I 65 and asecond pair of movable wedge members I66 connected by Parallel links I61 and an intermediate link I66 so that said wedge members I66 may be protruded to a greater or less extent between the stops I65 and the ends of the valve rods I62. Link I68 can be operated manually or mechanically, and thereby the extent to which the valve rods are moved by the movement of the lever I63 may be adjusted manually or automatically. A coil spring I69 normally holds the lever I63 in operative. relationship to its thrust rod or camoperating member. In place of providing the passages I66 in the walls of the cylinders, said passages may be provided in the ball valve members I23 provided the valve members I6I are so mounted as to cooperate with said passages without interfering with the proper opening of the valve members I23 under the pressure developed in the cylinders during the power strokes. Such an embodiment isshown in Fig. 10.

The ball valve members I23 are provided with passages ",4 of suitable shape designed to be closed at the appropriate times by valve members I6I. Valve member I6I is slidable and rotatably engaged on pin I, said pin being permanently mounted in arm I10 and extending centrally member I6I againststop I16 formed on pin I1I. When valve member I6I is closing oriflce I14 it Spring I12 then acts to insure complete mounted on rocker arm I13 by pin I11 such a connection allowing ball valve member I23 .to open without hindrance when valve member I6I is closing orifice I14. Rocker arm- I13 is rotatably mounted on pin I18 and is actuated by appropriate cams on shaft 46 working through push rod I19. The ball valve members themselves may be operated to admit the liquid to the work cylinders and provide the controlled admission of fluid thereto if also mounted so that they will open without resistance under the pressure developed in the .cylinders during the power stroke while subject to operation by suitable valve operating rods extending into operative connection there-.

- correct time in the cycle of the engine as one piston nears the end of its power stroke push rod I19 is depressed. Ring member I62 is moved ,down- I15 formed on the arm I10. Spring I12 is designed and placed to hold valve wardly and engages ball valve member I23 of an associated cylinder forcing it downward a prede termined amount and allowing the liquid to flow into the associated cylinder for the commencement of the workstroke in that cylinder. At the correct time in-the cycle the downwardpressure on push rod I19 is released, spring I29 forces ball valve member I23 upward, carrying with it ring member I 82 and push rod I19, and reseats ball valve member I23 in its seat at the lower end of cylinder 2| at which time ring member I82 is freed from engagement with ball valve member I23 and thereafter exerts no influence upon it until the next appropriate phase in the cycle.

It will therefore be perceived that a novel engine has been provided which employs a floating piston that is so combined with energy transferring means that a highly eflicient, accurately controllable and smoothly operating engine is provided. Moreover, a combustible mixture is exploded under conditions whereby the energy derived is utilized with maximum eiflciency, since the expansion of the mixture under combustion is, converted into the kinetic energy of movement of piston 42 without the losses heretofore characteristic of engine cycles wherein compression of the charge continues after combustion begins, while the expansion of the burned mixture is substantially unrestrained as well as complete so that the development of heat by delayed combustion or restrained expansion, which heat is largely dissipated through the engine walls or in the exhaust gases, is kept to a minimum. While the dissipation of energy by heat is not entirely eliminated experience has demonstrated that the loss of energy by heat dissipation is so far reduced that the engine does not become overheated although no means are provided for circulating a cooling medium in heat interchanging relation with either the cylinder head or the cylinder walls. Hence a saving in the weight of the parts required for sucl'f cooling systems as have heretofore been employed is eifected, and as the engine remains relatively cool in operation, there is less danger from the warpage and injury to the parts that arises from high heat, so that the engine can be made of lighter construction than heretofore considered feasible for like outputs of power.

The energy'derived from the motive fluid is therefore largely converted into kinetic and potential energy, and the efliciency of the engine is therefore relatively high. Not onlyonay the float-- ing piston move at the rate determined by the natural tendency of the fluid to expand but in the 'case of a combustible mixture it moves at the rate determined by the tendency of the gases to expand under free combustion in the presence of an adequate supply of oxygen. Also full advantage is taken of the inertia of the moving piston to transfer energy to the fluid within the tank.

'The pressure on the fluid within the tank is so selected as to assure that each floating piston will be brought to rest at theappropriate position for the end of its explosion stroke, which also assures that there is sufilcient pressure on the liquid to effect the working stroke without any large change in relative pressure of the gas on the-oil. As before noted, as soon as the pressure on the piston exceeds the pressure in the tank the outlet valve for the cylinder '2I is opened, and throughout the explosion stroke the oil is forced from the cylinder into the tank at the rate at which the piston moves under the action of the expanding gases. As soon-as the plunger H comes to rest as because of the dropin the pressure of the ex-' panding gases that is driving piston 42, and the momentum of the moving parts is overcome by the pressure on the oil, the valve closes because at this instant substantially atmospheric pressure is acting on the top of the

piston pair

42, 44, while the pressure within the tank is acting to close the valve. As any oil remaining in the cylinder 2| is substantially incompressible and therefore inexpansible, and as thepiston' 44 cannot rebound without creating a vacuum at its under side, the piston 44 therefore tends to remain stationary at the bottom of its stroke until such time as the corresponding valve 1| is opened to admit oil under pressure into said cylinder 2i. Hence any rebound of the piston at the end of its stroke is eifectively prevented.

As soon as the valve'between the tank and a work cylinder is opened the oil under pressure flows into the work cylinder at the rate determined by the size of the passages, which may be controlled and adjusted by the valve mechanism provided. In fact the oil being forced from one cylinder 2| is, as to a considerable portion thereof, displacing an equal quantity of oil into the other cylinder 2|, so that one piston 44 is moving the other piston 44 indirectlvthrough the intermediary of the oil in the tank l0. -But the inflow of oil into the second cylinder 2| is at a uniform rate and under a substantially uniform pressure,

efliciency, because throughout the stroke the de-' livery of energy from the rack 41 to the segmental gear 48 is substantially at right angles to the axis of the driving shaft, and therefore the power losses heretofore characteristic of crank mechanisms are avoided.

As one segmental gear comes into operation just prior to the preceding segmental gear going out of operation, the delivery of power to the driving shaft is smooth and regular, and without interruption, and hence there is an absence of shocks, jars, vibrations, etc. Also the force 'of expansion in the combustion chamber and acting on the liquid in the tank is equalized by the elastic medium in the tank, and any shocks and jars that would otherwise be created by the ignition of the charge as well as vibrations are eliminatedby uid to each cylinder 2|, and also the admission and exhaust of the combustible charge to and from the combustion chambers, and the admission and exhaust of the air or charge to and from each compressor, and the ignition of the charge, are all under the control of the driving shaft, which in turn-is moving at the controlled rate determined by the flow of oil into the cylinders 2 I. Hence any irregularities in the rate of movement of the pistons in the combustion chambers are not reflected in the rate of movement of the driven parts. This enables the rate of power delivery to be nicely adjusted without loss of emciency in the combustion chambers, becausethe'pistons in the combustion chambers may move at a relatively highand varying speed in conformity with the speeds and loads. low, while its horse power per unit of fuel conefficient use and expansion of the gases therein; while the rate of work delivery may be controlled accurately since all of\,the other functions of the engine are under the control of the driving shaft moving at the controlled speedlof the working pistons. On the other hand, the present inven-v tion makes possible the development of relatively high power or high speed although the number of explosions per minute are kept relatively low, because by varying the rate of delivery of the liquid into the work cylinders the rate of power delivery can be varied independently of the rate of which explosions occur, and therefore the present invention enables the development of power for speed or speed for power. Furthermore, while the fuel mixture may be maintained constant under variations or load, if preferred, the fuel mixture may be varied which will vary the length of the a power strokes and therefore the power or speed developed.

The present invention further enables the clearance inthe cylinder to be reduced with corresponding increase in efficiency. Thus in the embodiment of Figs. 1 and 2 wherein-the fuel is injected into each power chamber after the compressed air is transferred thereto from the compressor and after the piston has reached the top of its stroke, the cylinder clearance can be reduced to that amount that is suitable to provide for the proper volume of air. to combine with the injected fuel under such pressure as can be efliciently developed by the compressor, and a substantial increase in efliciency can' thus be obtained in accordancewith recognized principles governing increased pressure and decreased clearance. At the same time there is no danger of preignition because of the fact that the cylinder remains relatively cool and moreover, preignition would be without disadvantage because of the fact that the fuel is not introduced until E of the pistons and therefore largely restored to the tank by the operation of the pistons moving on their power strokes. Hence this restored pressure largely compensates for the power needed to operate the compressor, while the compressor, in the embodiment of Figs. 1 'and 2 particularly utilized for compression that part of the cycle where crank action is most efficient.

Furthermore, the present invention enables the heat units of the fuel consumed to be so utilized as work as to result in high thermal efiiciency,

" and at the same time the engine is simple in construction, strong and rugged in service and read.-

ily lends itself to a wide flexibility in use and design, so that it may be applied to various services and .deliver power under a wide variety of. Its weight per horse power is sumption is high.

While the embodiments illustrated on the drawings have been described with considerable particularity, it is to be expressly understood that the invention is not limited thereto. The principle underlying the present invention having been explained in detail, it 'will'at once be apparent to those skilled in the art that considerable departure may be made from the embodi merits illustrated and described-without depart- 15 mg from the spirit r the invention. The invention can also be applied to steamor air engineswith advantage. Although a liquid as well as an elastic medium are preferably used in the tank the invention asto certain features thereof can be used with advantage where the tank contains only a compressed gas, but withsuch a construction it is more dimcult 'to prevent leakage around the pistons and more dimcult to con- 10' trol the engine because of the compressibility of the operating fluid. Various other constructions of devices for compressing and introducing the fuel charge, transferring power from the pistons to the driving shaft, etc., may be used, various other forms of valves and valve operating mechanisms may be employed, other forms of elastic means may be used for cooperating with the 4 liquid in the tank, etc., and engines .may be built up of any suitable number of cylinders operating on the principle herein disclosed, or even a single cylinder may be used with some advantage, if a flywheel is also used, while changes may be made in the details of construction, materials, sizes, arrangements, and proportion of the various parts,

25 and certain features used without other features,

without departing from the spirit of this inven-.

'4 tion. Reference is therefore to be had to the and work chambers, a receptacle containing a liquid and an elastic medium under compression, connections between each work chamber and said receptacle, to carry said liquid.

means for varying the rateof flow of said liquid 40 in said connections, a driving shaft, and means for disconnectingsaid driving shaft from each piston means during the combustion stroke thereof and for connecting said shaft to said piston means during the return stroke thereof.

2. In an internal combustion engine, cylinders providing a'plurality of combustion chambers and a like. plurality of work chambers, piston means in each associated pair of combustion and work chambers, a receptacle containing a liquid and anelastic medium under compression, connections between each-"work'cylinder and said receptacle to carry said liquid, means for controlling the rate of flow of said liquid in said connections, a driving shaft, means for discon-" lns ai riv shaft from c Piston 7. In an internal combustion engine, cylinders means during the combustion stroke thereof and for connecting said shaft to said piston means during the return stroke thereof, a separate compressor driiren by said driving shaft, and valve controlled connections for transferring a charge from said compressorto the combustion chambers.

3. In an internal combustion engine, cylinders providing a plurality of combustion chambers and a like plurality of work chambers, piston means in each associated pair of combustion and work chambers, a receptacle containing a liquid and an elastic medi under compression, connections between each work cylinder and said receptacle to carry said liquid, means for varying the rate of flow of said liquid in said connections,

a driving shaft, meansfor disconnecting said driving shaft from each piston means during the e combustion stroke. thereof and for connecting said shaft to said piston means during the return stroke thereof, and means controlled from, said driving shaft for igniting the charge in each combustion chamber after the piston therein has completed its return stroke. l

4 In an internal combustion engine, cylinders providing a plurality of combustion chambers and a like plurality of work chambers, piston means in each associated pair of combustion and work- -chamber,s; a receptacle containing a liquid and an elastic medium under compression, connections between each work chamber and said receptacle, a driving shaft, means for disconnecting said driving shaft from each piston means during the combustion. stroke thereof and for connecting said shaft to said piston means during the return stroke thereof, means controlled by said driving shaft for opening and closing communication between each of said work chambers' and said receptacle, and means for varying the size of said opening.

5. In an internal combustion engine, cylinders providing a plurality of combustion chambers and a like plurality of work chambers, piston means in each associated pair of combustion and work chambers, a receptacle containing a liquid and an elastic medium under compression, connections between each work chamber and said receptacle,

tacle when the corresponding piston means starts on its combustion stroke.

6. In an internal combustion engine, cylinders providing a pluralityof combustion chambers and a like plurality of work chambers, piston means in each associated pair of combustion and work chambers, a receptacle containing a liquid and an elastic medium under compression, valve controlled connections between each work chambet and said receptacle, means for controlling the time of opening of said valve, a driving shaft, and means for disconnecting said driving shaft from each piston means during the combustion stroke thereof and for connecting said shaft to said piston means during the return stroke thereof, said last named means providing substantially ea right angle transmission of power to said driving shaft throughout the work stroke of each Piston means.

providing a plurality of combustion chambers and a like plurality of work chambers, piston means in each associated pair of combustion and work chambers, a receptacle containing a liquid and an elastic medium under compression, valve controlled connections between each work chamher and said receptacle, means for controlling the time of opening said valve, a driving shaft, and means for disconnecting said driving shaft from each piston means during the combustion stroke thereof and for connecting said shaft to said piston means during the return stroke thereof, said last named means for one piston means remaining connected to said driving shaft until said connecting means for another piston means has become connected with said driving shaft.

' 8. In an internal combustion engine, in combination with a driving shaft, means providing a. plurality of combustion chambers, a piston in each chamber adapted to be moved by the exaosasoa pansion of an ignited combustible mixture unrestrained by mechanical connection to said driving shaft, a receptacle containing a liquid and a compressed elastic medium, means providing a like plurality of work chambers adapted to communicate with said receptacle, piston means in each of said work chambers connected to one ofsaid first named pistons and adapted to. force liquid into said receptacles and another of said work chambers and tofurther compress said elastic medium during the combustion stroke of said piston, and means to connect the piston means in the cylinder into which liquid is being forced to said driving shaft while liquid is being forced thereinto.

9. In an internal combustion engine, in com-.

bination with a driving shaft, means providing a plurality of combustion chambers, a 'pistonin each chamber adapted to be moved by the expansion of an ignited combustible mixture unrestrained by mechanical connection to said driving shaft, a receptacle containing a liquid and a compressed elastic medium, means providing a like plurality of worklchambers adapted to communicate with said receptacle, pistonv means in each of said work chambers connected to one of said first named pistons and adapted to force liquid into. said receptacle'and another of said work chambers and to further compress said elastic medium during the combustion stroke of said piston, means for controlling the rate of flow of said liquid into said work chamber, and means to connect the piston means in the cylinder into which liquid is being forced to said driving shaft while liquid is being forced thereinto, said last named means applying torque to said driving shaft substantially at right angles there-' to throughout the work stroke of said piston means.

10. In an internal combustion engine, in combination with a driving shaft, means providing a" plurality of combustion chambers, a piston in each chamber adapted to be moved by the expansion of an ignited combustible mixture unrestrained by mechanical connection to said driving shaft, a receptacle containing a liquid and a compressed elastic medium, means providing a like plurality of work cylinders adapted to communicate with said receptacle, piston means in each of said work chambers connected to one of 'said first named pistons and adapted to force to said driving shaft whileliquid is being forced thereinto, and valve means operated by said driving shaft for, controlling the admission of liquid to each work chamber. Q

11. In an internal combustion engine, in com- I bination with a driving shaft, means providing a plurality of combustion chambers, a piston in each chamber adapted to be moved by the expansion of an ignited combustible mixture unreton, means to connect the piston means in the cylinder into which liquid is being forced to said driving shaft while liquid is being forced thereinto, and a pressure controlled valve for opening communication between each work chamber and said receptacle when a piston starts on its combustion stroke, said valve closing said communication as soon as said piston stops on its combustion stroke.

12/in an internal combustion engine, in combination with a driving shaft, means providing a plurality of combustion chambers, a piston in each chamber adapted to be moved by the expansion of an ignited combustible mixture unrestrained by mechanical connection to said driving shaft, a receptacle containing a liquid and a compressed elastic medium, means providing a like plurality of work chambers adapted to communicate with said receptacle, piston means in each of said work chambers connected to one of sa d first named pistons and adapted to force liquid into said receptacle and another of said work chambers and to further compress said elastic medium during the combustion stroke of said piston, means for controlling the time of flow of said liquid into said work chamber, means'to connect the piston means in the cylinder into each chamber adapted to be moved by the expansion of an ignited combustible mixture unrestrained by mechanical connection to said driving shaft, a receptacle containing a liquid and a compressed elastic medium, means providing a like plurality of work chambers adapted to communie cate with said receptacle, piston means in each of saidwork chambers connected to one of said first named pistons and adapted to force liquid into-said receptacle and another of said work cyl= inders and to further compress said elasticmedium during the combustion stroke of said piston,

means for controlling the time and rate of flow of said liquid into said work chamber, and means to connect the piston means in the cylinder into which liquid is being forced to said driving shaft while liquid is being forced thereinto, said last named means remaining connected to said driving shaft until another piston means is connected to said driving shaft.

14. In an internal combustion engine, in combination with a driving shaft, means providing a plurality of combustion chambers, a piston in each chamber adapted to be moved by the expansion of an ignited combustible mixture unrestrained by mechanical connection to said driving shaft, a receptacle containing a liquid and a compressed elastic medium, means providing a like plurality of work chambers adapted to communicatewith said receptacle, piston means in g piston, means for controlling the time and rate of flow of said liquid into said work chambenmeans to connect the piston means in the cylinder into which liquid is being forced to said driving shaft while liquid is being forced thereinto, and means controlled by said driving shaft for igniting a fuel charge in each combustion chamber after the piston therein has reached the end of its return stroke.

15. In an internal combustion engine, in combination with a driving shaft, means providing a plurality of combustion chambers, a piston in each chamber adapted to be moved by the expansion of an ignited combustible mixture unrestrained by mechanical connection to said driving shaft, a receptacle containing a liquid anda compressed elastic medium, a plunger means in said receptacle separating said liquid and said compressed elastic medium, means providing a like plurality of work chambers adapted to communicate with said receptacle, piston means in'each of said work chambers connected to one of said first named pistons and adapted to force liquid into said receptacle and another of said work chambers and to further compress said elastic medium during the combustion strokeof said piston, means to connect the piston means in the cylinder into which liquid is being forced to said driving shaft while liquid is being forced thereinto, and said plunger means in said receptacle retaining said liquid in operative position with respect to the piston means in said work cylinders irrespective of the vertical position of said liquid with respect to. said receptacle.

16. In an internal combustion engine, in combination with a driving shaft, means providing a plurality of combustion chambers-and a like plurality of work chambers a floating piston in.

a each combustion chamber connected to a piston in an associated work chamber, a receptacle containing a, liquid and a compressed elastic medium formaintaining said liquid under a substantial pressure, means of communication between the liquid in said receptacle and each of said work chambers, each floating piston being adapted to move its associated work piston to force liquid from its work chamber into said receptacle at the rate determined by the normal expansion of a 'fuel mixture under combustion,

each combustion chamber connected to a piston.

in an associatedwork chamber, a receptacle con-,- taining aliquid and a compressed elastic medium for maintaining said liquid under a substantial pressure, means of communication between the liquid in said receptacle and each of said work chambers, each floating piston being adapted to move its associated work piston to force liquid from its 'work chamber into said receptacle at the rate determined bythe normal expansion of a fuel mixture under combustion, and means normally closing communication between each" work chamber and said receptacle but opened by the pressure generated by the combustion of the fuelcharge in the corresponding combusfuelcharge. 18. In an internal combustion engine, in com- I is being forced bination with a driving shaft; meansproviding a plurality of combustion chambers and a like plurality of work chambers, a floating piston in each combustion chamber connected to a piston a. fuel mixture under combustion, said pistons being disconnected from said driving shaft throughout the combustion strokes thereof, and means for connecting each work piston to said driving shaft throughout the 'period that liquid into the corresponding work chamber.

19. In aninternal combustion engine, in combination with a driving shaft, means providing a plurality of combustion chambers and a like plurality of work chambers, a floating piston in the rate determined by the normal expansion of a fuel mixture under combustion, and means for controlling the time at which said liquid under pressure in said receptacle flows into a second work chamber to move the piston therein on its work stroke.

20. In an internal combustion engine, in com- .blnation with a driving shaft, means providing a plurality of combustion chambers and a like plurality of work chambers, a floating piston in each combustion. chamber connected to a piston in an associated work chamber, a receptacle containing a liquid and a compressed elastic medium for maintaining said liquid under a substantial pressure, means of communication between the liquid in said receptacle and each of said work said valve means and the time of flow of said second work chamber, and means for connecting liquid under pressure in said receptacle into a each workpi'ston to said driving shaft during its work stroke, said last named means delivering power to said driving shaft by a right angular application of torque; thereto throughout the vworking stroke of said piston.-

21. In an'internal combustion engine,'in combination with a driving shaft, means providing a I plurality of combustion chambers and a like plurality of work chambers, a floating piston in each combustion chamber connected to a piston in an associated work chamber, a receptacle contain- ,ing a liquid and a compressed elastic medium 7 for maintaining saidliquid under a substantial pressure, means of communication between the 75 each combustion chamber for compressing a gaseous charge to be delivered to said chamber,

' means for transferring said charge to said chamber, and means for igniting a fuel mixture in said chamber when the piston thereof has reached the end of its return stroke. 1

22. In an engine, in combination with a driving shaft, means providing ,a plurality of power chambers and a like plurality of work chambers, a floating piston in each power chamber connected to a piston in an associated work chamber, a receptacle containing a fluid maintained under a substantial pressure, means of communication between said receptacle and each of said work chambers, means for. controlling the rate of flow of said liquid into each of said work chambers, each floating piston being adapted to move its associated work piston to force fluid from its work chamber into said receptacle at the rate determined by the normal expansion of the motive fluid in said power chamber, said pressure fluid flowing from said receptacle into a second work chamber to move the piston in said work chamber on its working stroke, and means for connecting each work piston to said driving shaft only during its working stroke.

23. In an engine, in combination with a driving shaft, means providing a plurality of power chambers and a like plurality of work-chambers, a floating piston in each power chamber connected to a piston in an associated work chamber, a receptacle containing a fluid maintained under a substantial pressure, means of communication between said receptacle and each of said v worl' chambers, each floating piston being adapted to move its associated work piston to force fluid from its work chamber into said receptacle at the rate determined by the normal expansion of the motive fluid in said power chamber, said pressure fluid flowing from said receptacle into a second work chamber at a substantially uniform rate to move the piston in said work chamber bers, a floating piston in each power chamber connected to a piston in an associated work chamber, a receptacle containing a fluid maintained under'a substantial pressure, means of communication between said receptacle and each of said work chambers, each floating piston being adapted to move its associated work piston to force fluid from its work chamber into said receptacle at the rate determined by the normal expansion of the motive fluid in said power chamber, 'said pressure fluid flowing from said receptacle into a second work chamber at a sul stantially uniform rate to move the piston in sa:' 1 work chamber on its working stroke, means for connecting each work piston to said driving shaft only during its working stroke, and a valve cooperating with each of said work cham rs to motive fluid by combustion, medium by the action of said expanding motiveon its working stroke, means for connecting each fluid at a greater rate than it is to" be utilized permit flow of fluid therefrom and to prevent rebound of the piston therein at the end of the power stroke. a v

25. In an engineTin combination with a driving shaft, means providing a plurality of power chambers and a like plurality of work chambers, a floating piston in each power chamber connected to a piston in an associated work chamber, areceptacle containing a fluid maintained under a substantial pressure, means of communication between said receptacle and each of said work chambers, means for controlling the rate of flow of said liquid into each of said work chambers, each floating piston being adapted to from its work chamber into said receptacle at therate determined by the normal expansion of the motive fluid in said power chamber, said pressure fluid flowing from said receptacle into a second work chamber at a substantially uniform rate to move the piston in said work chamber on its working stroke, and means for connecting each work piston to said driving shaft only during its working stroke, said last named means providing a right angle transmission of torque from each work piston to said driving shaft throughout the working stroke thereof.-

26. In an engine, in combination with a driving shaft, means providing a power chamber and a work chamber, a floating piston in said power chamber .connected to 'a piston in said work chamber, a receptacle containing a liquid and is connected to said driving shaft only during the work stroke thereof. 4

27. The method of utilizing the energy developed by a motive fluid ina combustion engine which includes the steps of expanding the displacing a liquid .ment while simultaneously compressing an elastic medium by that displacement of the liquid medium which is in excess of that flowing to the driven element, and continuing the flow of said liquid medium to said driven element by the pressure of said compressed elastic medium.

28. The method of utilizing the energy developed by a motive fluid in a combustion engine which includes the steps of expanding the motive fluid by combustion at a rate which is determined by therate of combustion, displacing a liquid medium by the action of said expanding motive fluid at the variable rate determined by the rate of expansion of said motive fluid and which is in excess of its rate of useby adriven 1 element during a portion of the expansion period,

expanding motive fluid into drivin relation with said driven element and simultaneously compressing an elastic gaseous medium by that displacement of the liquid medium which is in extinuing the 110w of said liquid medium to said- 12 v cess of that flowing to the driven element, condriven element by the potential energy stored in .said elastic medium, and controlling the rate of flow of said liquid medium to said driven element to determine'the work function of the engine.

29. The method of utilizing the energy developed by a motive fluid in a combustion engine which includes the steps of expanding the motive fluid by combustion, displacing an element and a liquid medium in contact therewith by the action of said expanding motivefluid at the variable rate determined by the rate of expansion of said motive fluid and which for a portion of said period of expansion is in excess of the rate of use of-said liquid medium by a driven element, flowing said liquid medium by the action of said expanding motive fluid into driving relation with said driven element and simultaneously compressing an elastic medium by that displacement of the liquid medium which is in excess of that flowing to the driven element, utilizing the potential energy of said compressed elastic medium to continue the flow of said liquid medium to said driving element after the rate of flow of the liquid medium by the expanding motive fluid has decreased, and then reversing the movement of said driven element by the combustion of said motive fluid to drive said first named element in the opposite direction by flowing said liquid medium and compressing said elastic medium as defined.

v WILLIAM F. DOG-AN.