US1743023A

US1743023A - Internal-combustion engine

Info

Publication number: US1743023A
Application number: US120311A
Authority: US
Inventors: Russell S Carter
Original assignee: Individual
Current assignee: Individual
Priority date: 1926-07-03
Filing date: 1926-07-03
Publication date: 1930-01-07
Anticipated expiration: 1947-01-07

Description

R. s. CARTER 1,743,023

INTERNAL COMBUSTI ON ENGINE Jan. 7, 1930.

Filed July 5. 1926 4 Sheets-Sheet 1 Jan. 7, 1930. 5 CARTER 1,743,023

INTERNAL COMBUSTION ENGINE Filed July 5. 1926 4 Shets-Sheet 2 Jam. 1?, 393%,

R. s. CARTER INTERNAL COMBUSTION ENGINE July 5. 1926 4 Sheets-Sheet Filed W .H We

Jan. 7, 1930. w R 5 CARTER 1,743,023

INTERNAL COMBUS TI ON ENGINE Filed July 5. 1926 4 Sheets-Sheet 4 87 i iNVENTOR 55 V Patented Jan. 7, 1939 UNITED STATES "PAT r Fries RUSSELL S. CARTER, O1? HEWLETT, NEW YORK INTERNAL-COMBUSTION ENGINE Application filed July 3,1926. Serial No. 120,311.

There is more or less crank case contamination, as is well known, in the operation of internal combustion engines on liquid fuels of considerably lighter gravity than the lubricating oil. That is to say, more or less of the fuel finds its way past the piston into the lubricating oil, and this reduces the viscosity of the lubricant and its lubricating qualities. It has heretofore been proposed to distill the lubricating oil, i. e. vaporize the lighter fuel oil, by applying heat to the fuellubricant mixture, and usually this has been done by means of a vaporizer, external to the engine, between which and the lubricant sump a circulation of the fuel-lubricant mixture is maintained while the engine is in operation. While this practice limits the degree of contamination, it does not prevent crank case contamination as is obvious.

I contemplate recovering the fuel which enters the crevice between the piston and cylinder wall before it has an opportunity to mix with the main body of lubricating oil. With the common hollow type of piston, I prefer to direct this escaping fuel into the hollow of the piston, from whence it can be recaptured readily. Also I contemplate using the engine piston or pistons to vaporize the liquid fuel entering the crevices between the pistons and the cylinder walls. Ordinarily the piston is quite the hottest part of an internal combustion engine and is a source of adequate heat to vaporize the escaped fuel. Furthermore, thereby I make use of the latent heat of vaporization to moderate the temperature of the piston. The fuel may be vaporized on the outside of or within the piston and the products of the vaporization can be re turned to the combustion spaces directly, or removed from the engine case by suction, or blown out, and thence can be discharged into the atmosphere or passed into the engine intake passages, or returned to the body of liquid fuel at a convenient point, in the last case usually after condensation. Ordinarily I use suction when the vapors are to be removed from the engine case. The quantity of lubricating oil taken out of this case along with the fuel vapor can be limited by oil traps placed along the outgoing lines,or when the fuel is vaporized, by arranging to take the fuel vapor from a high point in some chamber or space where the fuel vapor tends to collect above the lubricating oil because of the greater specific gravity of the latter; both expedients can be resorted to conjointly. For example, in vertical engines, when the fuel is delivered into or developed within the cylinder space below the piston heads in the form of vapor, openended outlet pipes, telescopic or otherwise, can be extendedupwardly to points close to the underside of the piston heads, or at least well up into the cylincers, to withdraw the vapor. Especially in such situations I contemplate sweeping out the fuel vapor by an air flow of large volume, and to assist this sweeping out of the fuel vapor without entraining an undue amount of the lubricant, the air to sweep out the vapor can be admitted into the engine case through open-ended inlet pipes similarly extending up into each cylinder and placed more or less diametrically opposite the outlet pipes, so that the air flow is substantially localized to the region of the densest fuel vapor and above the region of considerable crank case fog, i. e., above the region of the denser atomized or vaporized lubricant. vVith certain engine constructions however,

it may be desirable to employ air outlet or inlet ports opening into the crank case below the cylinders in addition to or as substitute for the outlet and inlet pipes within the cylinders. -A regulating valve or valves may be added to proportion the air flow these two ways as conditions dictate.

Locating the inlet pipe, or both the inlet and outlet pipes, with its or their ends within the cylinder space accomplishes another i1nportant function, namely, the, air flow tends to cool the piston head by reason of its contact with or through ventilation of the region of the piston head. An air inlet pipe, or both inlet and outlet pipes, within each cylinder space is useful for this purpose alone, that is to say, independently of and unaccompanied by prevention of crank case contamination.

About an internal combustion engine there are a number of parts subject to reduced atthrough the crank case.

' case.

mospheric pressure and hence potential sources of suction to create the air flow However, since an air flow of large volume seems preferable, the air intake of the carburetor is the most suitable natural suction source from this standpoint, and furthermore this arrangement preserves any recovered fuel by returning it to the engine for combustion use and tends to riclien the combustion mixture for a time after starting when an unusually richmi'xture is desirable. If taking all the combustion air through the engine case tends 'to extract too much of the lubricating oil or imposes an unnecessary restriction on the floiv of combustion air, a part of thejcombustion air can be furnished independently of thecrank case, only a part being taken through the A fixed leak from atmosphere, for example, will permit acertain part of such suction-created air flow to 'be taken direct from the atmosphere; or a regulating valve may be interposed in the leak to permit regulation of--the -part of the combustion air tobe taken through the engine case and the part to be furnished independently of the crank case.

'Such a valve maybe independently adjusted, or interconnected for conjoint operation with one or more of the engine controls. For example, it may be so interconnected with they throttle thatincreasing the throttle opening causes a'larger part of the total combustion air to be taken in independently of the engine case, thus relieving the restriction on the air flowfwhen high speeds or large loads demand great power from the 'engine,-as hereafter referredto again. Also for example, since "the greatest deliveries of fuel in the form of liquid to the combustion space occur when the engine is choked, the regulating valve may beinterconnected with the choke, either independently of the throttle or conjointly with the throttle but in such manner that all or a large part of the total air is taken through the crank case whenever the choke valve is closed. regardless of the'position of the throttle. This produces the maximum fuel-reinovingflow at the time when most needed;

'however, this arrangement also produces maximum piston cooling at starting, when quick heating of the engine is frequently highly desirable, and hence where such cooling predominates another relation may be hereafter. I

If desirable, the suction ofthe carburetor can be aided or supplanted in causing the air flow through the engine case. A blowermay be usedeither engine driven or driven 'byits own motor; the engine pistons also may be used forthis'purpose as hereafter explained. Thus if the factorof piston cooling suflers unduly by limiting-theair flow to less'than maximumathigh loads and high s'peedsithat is to say, at those times when heatisdeveloped "at the greatest rate, such aids or substitutes "plugs at 5,

so as to obtain the maximum or an increased flow through the engine case at wide open throttle without unduly limiting the volume of combustion air supplied to the engine. 7

Such aids may be kept in constant operation so long as the engine is running, or brought into operation'oiily as the throttle. position or other conditions dictate.

Regulation can also be obtained by regulating the tendency of the aid to move air, or by a passage-restricting valve or valves, or by valved leaks to or from the atmosphere on the carburetor side of the valve, or the side toward the aid, or both. By'employing a suitable device or arrangement, a greater volume of air may be employed for cooling, for example, than is required for combustion, the part not needed for combustion being bled off. A blower' detailsof construction which bring about the recovery of the fuel. a V

The invention is illustrated in the accompanying drawings, ratherdiagrammatically, in connection with multi-cylinder engines. Fig. 1 is a vertical section of such an internal combustion engine with my invention applied. Fig. 2 is an elevation of the same' engine, partly in section. Fig. 3 is a sec tional plan View of the same substantially along the broken line III-III of Fig. 1. Fig. 4 is a perspective diagrammatically illustrating the interconnection of the throttle, choke and by-pass regulating valves of Figs. 1 and 2. Figs. 5, 6 and 7 are respectively a vertical section, elevation and plan of one of the inlet valve structures of the engine of Fig. 1. Fig. 8 illustrates another porting for the admission of air to the cylinder spaces. Fig. 9 is a vertical section of an engine embodying another form of my invention. Fig. 10 is an elevation of the engine of Fig. 9. Fig. 11 is a sectional plan thereof, substantially on the line XI-XI of Fig. 9. Fig. 12 is a sectional elevation of a modification of a detail. Figs. 13, 14, '15 and 16 are'sectional views of further modifications.

Many details of engine construction have been omitted from various figures of. the

drawing, as will be apparent. Referring first to Figs. 1 to 7: The engine case comprising the usual crank case 1, the cylinder'block or blocks'2, which are'vertically mounted'therei on, and the head '3, which is illustrated as detachable from the-cylinder block. Custoimary enginevalves areindicated at 4, spark carburetor at 6, throttle valve at '7,-int'akemanifold at 8, andth'e pistons at i 9 within the cylinders. The pistons are of hollow type, as will be seen from Fig. 1, and somewhat below the piston head and piston rings 14 are pierced with a series of holes 10, which, externally of the piston, open into circumferential grooves 11, one in each piston. Liquid fuel passing the piston heads and moving toward the lubricant sump in the bottom of the crank case 1, enters the grooves 11 and therefrom is directed through the ports 10 to the inside surface of the wall of the respective piston. If desired, an oil collecting ring 12 may be located in the groove 11 to assist in trapping the fuel and direct ing it into the ports 10; by oil collecting ring, it will be understood of course, I refer to pie ton rings which are pierced radially and usually grooved circumfercntially, such as are commonly used in internal combustion engines to prevent an excess of lubricating oil from creeping upwardly along the cylinder wall into the combustion chamber, If desired also, additional rows or series of ports can be pierced lower down in the piston walls to intercept any fuel passing the first series; another such row is illustrated at 13 together with its own collecting ring 12, but usually one or two rows of ports 10 in the upper half of the piston will be sufficient. The fuel passing through the ports 10 and 13 in liquid form, along with any lubricating oil that may be entrained, is delivered into the receptacles or

lips

17 and 18 respectively placed below each series of holes, which cause the fluid to be retained in contact with the piston walls long enough to permit the fuel to be vaporized; the unvaporized oil will find its way down the piston walls into the sump. The upper edge of each lip may be placed below lLS ports as illustrated, so that even if the lip should become t ll d with fuel and oil, there will be no tendency for this accumulation to cause a backward flowthrough the ports 10. Further, the upper edges of the lips (see lip 17, Fig. 1) may be turned back away from the axis of the piston so that any liquid thrown out of the receiver by the reciprocation of the piston will be thrown against the walls of the piston rather than toward the axis from whence the liquid might fall into the lubricant sump. It will be understood however that the lips or receivers for the fuel ano oil may assume various forms, their purpose being, in Figs. 1 to 7, principally to delay the immediate flow of the fuel liquid down the piston walls and thence into the lubricant sump and to cause the fuel liquid to be retained on the walls of or in heat-exchange relation to the piston for sufficient time to permit the heat of the piston to vaporize the fuel; in certain cases, no added lips may be needed at all, the mere length of the piston or irregularities of its surface retaining the fuel long enough to assure vaporization.

The fuel vapor thus produced in the hollow of each piston is removed through the outlet stand pipes 21, of which thereis one or more for each cylinder as appears from Fig. 3. These stand pipes reach up into the cylinders from below and are secured by the brackets 22, their upper open ends being telescoped by the pistons as the latter move downwardly, and reaching not quite to the piston heads when the pistons are at the extreme ends of their expansion strokes. Air is admitted to the cylinder spaces and the hollows of the pistons through similar stand pipes 23 ;cthat is to say the stand pipes 23, open at their upper ends, also extend upwardly into the. cylinder chambers from below and are carried by brackets 22 and reach not quite to the piston heads when the pistons are at the ends of their expansion strokes. The

stand pipes

21 and 23 of each cylinder are located more or less opposite each other as appears from Fig. 3. For convenience or construction, I usually use a single inlet structure 24 for each two adjacent stand pipes 23 (see Figs. 1, 3 and 5), and these structures can be ex-- tended up into the chamber containing the valve push rods 25 as illustrated in Fig. 1, so that the air flow aids in cooling the push rods and valve springs as well as to extract the fuel vapor and cool the pistons. Louvers 26 and 27 in the plates closing the chamber for the push rods permit the entry of air and with cloth or wire screens 28 clean the incoming air. Usually I also arrange the outlet pipes 21 in pairs similar to the pairing of the pipes 23 (see Fig. 3), and all these outlet pipes open into an outlet manifold 31 running substantially the length of the engine. The manifold 31, in turn, opens by means of a passage 32 extending across air intake of the carburetor 6, so that the latter may take all its air by way of the

passages

32 and 33 and through the engine casing.

over the outlet pipes 21tends to produce a noticeable inspiration and aspiration through the pipes 21 and interchange of air through tiie manifold 31, with a surging tending to disturb the desired delivery of air to the car-, buretor and the proportions of the combustion mixture, valves such as 33 can be added to prevent air passing backwards from the manifold into the pipes 21. These valves 33 can be light flap valves, one for each of the;

pipes 21, closed by gravity and any tendency there may be for the air to flow backwards. Stops 3 1 prevent these flap valves opening too far, and for convenience they are mounted in cages 35, one cage and pair of valves, these cages being inserted into the manifold 31 at the feet of the pipes 21 and the openings for the cages covered by plates 36.

The entire volume of the combustion air,i3

the engine to the- If the reciprocating action of the pistons;

for each pair of pipes 21;;

more or less to the exclusion of air "taken throughthe engine case by Way of the crosspassage 32; thisleak is shown in the drawings as closed by a'flap valve 41 carried on a pintel '42. In the present instance, this added valve '41 g is 'interconnected with the carburetor throttle 7 and choke in such a manner that more or less of'the combustion'iair is taken 32o in throughthis leak'39 as'the engine i'scalled on for more power -'for higher speeds or greater-loads, thereby more or less remov ng therestrictionimposed by theengine case=on the flow of combustion air andpermitting 125 greater charges of combustible mixture to be fed-to the cylinders, and also when startingthe engine, at :which latter'time it is ifre quently desirable-that the cooling effect of theair flow on'the'pistons be eliminated in 30 order that the engine'maywarm up as quickly as possible. This interconnection of the valve is best illustrated in the diagram of j 4. As appears in that figure, the throttle valve 7 is operated bythe rod'43 andvan arm 85 44 on the throttle'valve shaftyactingagainst a spring 38 which tends to close the throttle. An oppositely extending =arm45 on the throttle shaft connects with a rod 46 which leads to an arm 47 on, the 'pintle42 no of the leakvalve 41, and-a collar 48 is fixed to this-rod 46 in such a position as to strike the arm 47 and open the valve41 atth'e proper time, usually after the throttle 7 has been opened to a certain extent, say about onells-eighth or one-quarter'of its ull opening; thereafter collar 48 opensthe-leakvalve along with the throttle according to some proper ratio as will be understood A spring 49 works against the thrust of the collar 48 60 and closes'the valve 41 when released by the collar. For connection'to the choke, an oppositely extending arm 50 on'the pintle 42 is arranged to receive an extension of the choke operating rod 51, which is shown provided with a collar-52 whereby the rod51 can close the choke 40 against a-spring tendingtoopen it, and also witha collar 53"for'picking up the arm and thereby-opening the valve 41; the v collar '53 is usually so placed-on the'rod 51 Mthat'the choke rod 51 does not'open the leaik valve 41 unlessthe choke 40 is itself moved to nearly closed position, or to {that position usually given'to the choke in starting the engine in cold weather. A slidin collar '56 on the rod 46, fixed collar 57"a'nd interposed cold piston to rise more 'quickly to a point where the engine acts well and Where the ducetl spri'ng 58 may act to or assist inclosin'gthe leak'valve'41, thesp'rin'g 58 and sliding of and-the -positionof therod 46.

Ordinarily I prefer this method ofopera- .tion, namely, eliminating or materially reducing-the 'flow of air through the engine 7 case,-while thechoke isclosed, since this oper- 'ation delays "thebe'gin'ning of piston cooling for a time and"permits the temperature of a piston'may act asa vaporizer. While the largest quantities of fuelindiquid form enter the combustion spaces at this time, when the engine'iscold and choked,=the increase in contamination is not-so great as mightbeexpected since the 'fuel liquid does not pass 35 over thepistons-and enter the sump immediately, but is delayed by the piston'rings and passes the rings rather slowly. Furthermore, I contemplate making the lip or

lips

17 and 18 of such capacity, as reservoirs, as

to retain such liquid aspas'sesthe rings until the piston heats up and'the-air flow is restored. Inthe'usual operation ofthe choke therefore I contemplate that the air flow will be restored in'time to perform its function of -'95 extracting the escaping 'fuel.

Figs. -1-'to"7 also illustrateone 'manner of aiding the 'engine suction in causing the air flow-through the engine case, such aid being aiforded'by the pistons themselves in conjunction with the valves 33 on the outlet pipes and further valves 59 on the air inlet pipes. One of-these valves 59'is provided for each inlet pipe 23 and they are so arranged as to permit a floW-of'air into the cylinder spaces but to prevent'a flow outwardly from the cylinder spaces through'the pipes 23. As shown in Fi s. 5, 6,'and 7 th'ese'valvesmay'be intro readily by dividing the air inlet 24 Q which of a partition 60, and hanging'on this partition the two corresponding flap valves 59; these may be assisted to their closed positions by light springs, such as61, although it will be apparent that the tendency for the ai-r'to' 115 f flow backwards out of the cylinders,--through the pipes 23, as the pistons reciprocate will dagain forcing out this air through the "pipe 21, and thus "the pistons,

:of them selves, producing an air 'flow through the cylinder chambers. If'necessary, "the restriction to a free interchange of air "from 130 serves two of the pipes 23, as by means I cylinder to cylinder through the crank case may be increased tothe desired extent, as by means of plates 62 of thin metal extending across the lower ends of the cylinders, but pierced, of course, for the passage of the

pipes

21 and 23 and the connecting rods extending etween the pistons and the crank shaft. Other means for increasing the restriction or even substantially entirely preventing the interchange can be devised readily. I have also illustrated an oil trap, in this case supplemental to the

pipes

21 and 23, for reducing the amount of oil taken out of the engine case along with the fuel. Here the trap consists simply of a small sump 63 into which the manifold 31 drains; a U-shaped pipe leading from this sump and opening within the crank case permits accumulations of oil in the sump 63 to pass therefrom into the crank case with.- out permitting air to pass from the crank case into the sump 63 and thence into the manifold 31 under the suction of the carburetor. I have also illustrated a heater for the manifold 31 and the air going to the carburetor, this heater being in the form of a passage 65 running beside the manifold 31 into which more or less of the engine exhaust can be directed at 66 and led out at 67 (Figs. 1 and 2) as will be understood.

While, as before pointed out, an inlet pipe leading well up into each cylinder, such as 23 for example, is preferable in most instances, it may be desirable or sufficient in some instances to admit air directly into the crank case by one or a distributed lot of holes 5 L (Fig. 1), either supplemental to or as a substitute for the pipes delivering directly into the cylinder chambers; when supplemental to such inlet pipes, the flow the two ways may be regulated, and for. the present purposes the holes 54: may be regarded as so chosen as to size and in such numbers as to afford suitable fixed regulation. In other cases the pipes 23 may be dispensed with by piercing an inlet port or ports in the wall of each cylinder at a point uncovered by the piston on its upward stroke. Such a construction is shown in Fig. 8, an inlet port for the sweeping out air being shown at 68. Reference characters heretofore used appearing on this figure identify various parts, so that the construction will be understood.

Figs. 9, 10 and 11 illustrate principally the use of a blower 7 5 in connection with or as part of my invention. Various modifications of general application are also illustrated. Of the latter character, it will be observed that the lip which aids in retaining the liquid fuel on the piston walls, may be a se arate plate 76 bolted or otherwise attached to the piston. At 77 is indicated a hole in this plate to permit the plate to pass down over the air outlet pipe 7 8 on the downward movement of the piston. The air outlet pipe 78 is like the outlet air pipe 21 of the preceding figures,

air flow. Valves corresponding to the valves- 33 may be used, however, if necessary, as ine dicated at 80, although the superior suction produced by or with the aid of the blower tends to render even these valves unnecessary. The presentfigures also illustrate that the incoming air can be taken 1n at 81, that is to say at the top of the case enclosing the valve rockers and after passing through this valverocker-case 82, passed down through the pipe 83, around the push rods 84, and thence to the intake pipe 79; thus the entire valveoperating system is cooled. They also illustrate that the outlet manifold 85 may be simply a pipe laid lengthwise of the engine and slotted at intervals opposite the feet of the outlet pipes 78; at these outlets are located brackets 86, each of which contains a flap valve for the corresponding outlet pipe 7 8 while yokes 87 and bolts 88 draw the pipe down against the brackets 86 with the slots opposite passages containing the valves 80. The blower 75 is interposed between the outlet of the manifold 85 and the intake of the carburetor, which are connected to the inlet port and outlet portof the blower respectively. An oil trap 89, however, with an oil return pipe 90, may be inserted between the manifold and the blower. In Fig. 10 the blower is shown as separately driven, that is to say, driven by an electric motor 91, and the motor 91 may be a source of regulation by affording regulation of the speed of the blower. As an alternative the blower may be driven by the engine itself, as directly by the fan belt 100 as shown in Fig. 12. In either case I ordinarily insert a regulating valve between the blower and the carburetor choke 40. The regulating valve illustrated com prising a chamber or part of the passage may open at one side and a valve 96 with two wings pivoted midway in the opening so that it can simultaneously open the blower outlet and the carburetor intake to the atmosphere as will be apparent from Fig. 10. In the pres ent instance I have illustrated the regulation for this regulating valve 96 as entirely independent and in no way connected to the throttle 7 or choke 40; it is not essential. however, that this valve be unrelated to the engine controls.

As before explained, a blower provides an adequate flow of air both for contamination prevention and piston cooling under all condition without restricting the power output of-the engine. Indeed the engine may be supercharged by the blower, that is to say,

the combustion or fuel mixture delivered tothe combustion spaces at super-atmospheric pressure, so that by one system I can prevent crank case contamination, moderate the temperature of the pistons, and increase the power of=the engine by supercharging.

Figs. 13 and 14 illustrate modifications of the contamination-prevention feature of my invention in which the escaping fuel is returned to the combustion spaces directly. These figures show sections of engine pistons. Referring first to Fig. 1-3 Adjacent: the top of the piston is placed a pierced liquidcollecting ring 106 similar to an oil ring, which can be'denominateda fuel collecting ringrather than an oil collecting ring because of its position and principal function. The central portionof the piston top or head is depressed to form a receiving chamber for the fuel at a pointon thepiston when the temperatureis higher than directly at the crevice and liquid fuel entering the crevice between the piston and its cylinder wall is goicollected by the ring 106 and-directed by the inclined passages-107, into the receiving chamber whence itmay be vaporized by the piston and consumed by the heat of combustion.

Obviously vaporizing from the recaptured liquid fuel is delivered directly into the combustion space. The-inclining of the passage 107 prevents fuel liquidbeingfed backwards toward the cylinder walls, and the'passages may open into the depression above the lowest point thereof for the same result. If desired this arrangement maybe used in combination with and supplemented by an internal lip such as 17 with its passages 10and collecting ring 12 before described. If carbon tends to closeisuchpassages as 107 unduly, they may be made in more generous proportions, other forms adopted or arrangements made to avoid the action. Thus, for example,in Fig.,

14, the outlet of each passage 107 lies in a plane making a sharp angle with the general plane of the piston head. Furthermore a flange-like protuberance 108 extends. inwardly over the piston head proper partially closing the receiving chamber on the head of the piston whereby it tends to retain unconsumed' liquid fuel on the heated surfaces for a longer time for vaporization purposes. The throat of the chamber may be made of proportionate size to give the best results, the flange being enlarged if necessary or desirable as indicated by the broken lines 109. I

believe it is better to open the outlet ends, of.

' the passages 1071above the edge of the lip flange 108,.as illustrated, rather than below it, in order that any-liquid that may be thrown oil the floor of the receiving chamber may not be thrown directly into the passages. The

pistons of these Figs. 13 and 14 and of Figs.

15 and '16 also may be assumed to be used with any ordinary carburetor type of engine using liquid fuel of considerably lighter gravity than the engine lubricant.

In Fig. 15 the fuel vapor is also delivered substantially directly into the combustion chamber for immediate use, the receiver or receiving chamber 115 for the liquid fuel being'entirely closed however so that the liq-.

uidis shielded from direct contact with the flame in the combustion chamber. The chamber 115 it will'be observed is within the piston, as illustrated, between two piston heads retaining plug is set in at 120. In vertical v engines at least I do not contemplate that a spring or any other arrangement will :be'need ed to hold the valve to itsseat, for on the working stroke the pressure Withinthe combustion space holds the valve down, and on the compression and exhaust strokes (fourcycle operation is assumed) the piston moves against the valve and'is somewhat supplemented by pressure. On the suction stroke I desire the Valve to open, and both the inertia of the valve and the suction in the com v bustion chamber tend to open it. Suction is then applied to the chamber 115 to evacuate it: and I contemplatethat suction will be applied in this manner to the passages 117' throughout the major part of each suction stroke, so that at least every fourth stroke.

applies suction to the cylinder wall to sweep off escaping fuel. In so far as the chamber 115 continues at reduced pressure after the valve 119 closes, suction is applied to the cyl-,

inder wall during the other strokes also. The outlet passages 118 may be elongated as illustrated, that is, its entrance located rather close to the flooror a sump of the chamber if it is desirable to return recaptured fuel to the combustion chamber in liquid form at.

any time, for example in case the chamber 115 should receive some time an overcharge of liquid fuel. The recaptured fuel is returned to the combustion chamber in the form of vapor however, proportionally to the eleva- V tion of the entrance of'118 above the chamber bottom.

The modification of Fig. 16 is rather similar to that of Fig. 15 in principle but is a form in which the invention can be applied to standard pistons. .The piston head is opened at the center and threaded. Into this opening is screwed the plug having a receiver or receiving chamber 126 for therecaptured fuel,

valve 127, and pierced valve retaining' plug 128. As before, the escaping fuel maybe recaptured in the circumferentialgroove129 (in which may be seated a fluid-collecting ring asbefore). Pipes 130 (as many as may conduct into the hollow of returns directly to the combustion space. By opening a passageway 131 from the hollow of the piston to the chamber 126, suction strokes will tend to withdraw vapors from the cylinder spaces and crank case also, and return them directly to the combustion space. The construction can be supplemented by a lip 17 ports 10 and collecting ring 12 such as shown in Fig. 1, for example, if desired, the vapors produced within the piston hollow by these means being returned to the combustion space directly instead of in the more roundabout manner illustrated in Figs. 1 to 7 in the alternative the lip, etc. with the passage 130 and valve 127, or analogous constructions,

may be used without the passages 131. If desired, either passage 130 or the up-rising passage leading directly to the valve 127 may be provided with valves for manual adjustment.

It will be understood that my invention is not limited to the details of construction illustrated and described above, except as appears in the following claims.

I claim:

1. In an internal combustion engine, means to retain on a piston until vaporized the liquid fuel passing the piston head, and a receiver for the products of such vaporization to keep the same from reaching the main stock of engine lubricant.

2. In an internal combustion engine, a piston having a recess to receive liquid fuel reaching the piston, and means for removing, from the engine case, products of vaporization from the liquid reaching said recess.

3. In an internal combustion engine, a hollow piston having an internal liquid-receiving recess opening to the hollow in said piston, a port to pass liquid fuel into said recess, and means for receiving products of vaporization from the liquid reaching said recess to keep fuel from diluting the stock of engine lubricant.

4. In an internal combustion engine, a hollow piston having a port to pass into the hollow of the piston fuel reaching the piston in liquid form, and means for removing fuel reaching the hollow of the piston without mixing said fuel with the main stock of lubricant in the engine.

5. In an internal combustion engine, a hollow piston having a port in its side wall to the piston liquid fuel passing the piston head, and means for removing such fuel from the engine case, said means taking the fuel from the piston.

6. In an internal combustion engine, a hollow piston having a port to pass into the hollow of the piston fuel reaching the piston in liquid form, said piston being adapted to retain liquid fuel passed into its hollow until said fuel is substantially entirely vaporized, and means for removing the fuel vapor from the engine case substantially as rapidly as it 1s formed.

7. In an lnternal combustion engine, a hollow piston having a port in its side wall to conduct into the hollow of the piston liquid fuel passing the piston head, said piston being adapted to vaporize fuel within it, and means for removing such fuel vapor from the engine case, said means taking the fuel vapor from within the hollow of said piston.

8. In an internal combustion engine, a hollow piston having a port in its side wall to conduct into the hollow of the piston liquid fuel passing the piston head, and having a baffle extending inwardly from the piston side wall below said port to restrain the flow of liquid entering the piston through said port.

9. In an internal combustion engine, a hollow piston having a port in its side wall to conduct into the hollow of the piston liq- ,uid fuel passing the piston head, and having a baffle extending inwardly from the piston side wall below said portto restrain the flow of liquid entering the piston through said port, and means for removing from the engine case the fuel vapor produced by the piston.

10. In an internal combustion engine, a hollow piston adapted to vaporize liquid fuel tending to pass the piston and deliver the vapor into the hollow of the piston, passageway means providing an outlet for the vapor leading from the hollow of the piston, and means for applying suction to said passageway.

11. In an internal combustion engine, a hollow piston adapted to vaporize liquid fuel tending to pass the piston and deliver the vapor into the hollow of the piston, passageway means providing an outlet for the vapor leading from the hollow of the piston,

passageway means providing an inlet for air opening into the hollow of the piston, and means for applying suction to said outlet passageway.

carburetor for the engine, said passageway leading to a carburetor air intake so that a vapor-removing air flowis created.

13. In an internal combustion engine, a hollow piston adapted to vaporize liquid fuel tending to pass the piston and deliverthe vapor into the hollow of the piston, two

stand pipes extending into the piston when the piston is at the end of its working stroke, and a carburetor for the engine, one of said stand pipes leading to an air intake of the carburetor and theother'stand'. pipe providing an inlet for air.

14. In an internal combustion engine, a hollow engine piston adapted to liquid fueltending to deliver. the fuel vapor into the hollow of:

the piston, and an outlet pipe. arranged to' conduct such vapor away, saidoutlet pipeder chamber to a .point close to the piston head when the pistonv isat the endof a .power stroke.

16. In an internal combustion engine, a: hollow engine piston adapted to vaporizeliquid fuel tending to pass thepiston and deliver the fuelvaporinto. the hollow ofthe piston, and'a pipe to-admitair to the engine case to sweep out such fuelvapo'r, saidpipei reaching into the interior of the; piston and delivering air therein. 7 17. In an internal combustion engine; a

deliver the fuel vapor into the hollow-ofthe piston,- and a pipe to admit air to the engine case tosweep-out' such fuel vapor, said pipe "being a stationary stand pipe reaching into the cylinder chamber to a point close to the piston head when the pistoniisat theend=of a power stroke.

18. In a multi-cylinder internalcombustion engine a plurality of hollow pistons,

I l ports in the sides thereof to pass into the hollows. of the pistonsthe liquid fuel tending t to pass the pistons, means withinthe pistons to retain said liquid fuel on the. pistons until vaporized thereby, a stationary air-inlet stand pipe and a stationary outlet stand pipe extending into each of said pistons to ad acent the head thereof when the respective piston V is at the end of its working stroke, a: blower, :the intake of which is connected-to saidoutlet pipes, a flow-operated valve in each of said outlet pipes to prevent flow therethrough 1nto the respective cylinder chamber, a carburetor, an air-intake of which is connected to the Q discharge of said blower, said blower be ng retor into the combustion spacesofthe engine at superatmospheric pressure, and-011 trap meansinterposed in'the linebetween the vaporizepass the piston and hollow engine piston adapted to. vaporize liquid fuel tending to pass the piston and adapted to deliver air through said carbu by thefactthat the. said valve isiconnected to one of the engine controls andisadjusted thereby.

V 21. In an internal. combustion engine, means for permitting a flow of air througha cylinder chamber of the engine, between the head of the piston therein andthe crank shaft, a blower tending to produce such flow, a car'- buretor' for the engine, passageway means;

directing such flow into an. air intake of the carburetor, and a valve for opening saidpassageway means tothe atmosphereto a regulatable amount. r

22. An internal combustion engine having a carburetor, characterized by the fact that a piston thereof hasia receiving chamber forliquid fuel within its cylindrical Wallstore ceive and vaporize fuel, and that the cylindrical wall of the piston is pierced with a passageway to conduct liquidfuel into said re- COIVGL- I p 23. The engine of claimr'22, further characterized by the fact that a liquid collectingring on the piston directs liquid fuel into the pierced passageway.

24-. An internal combustion enginehaving means at the side of the piston to collect liquid .fuel tending. to pass the piston and deliver it for vaporization to a. portion ofthe piston hotter than the side of the piston.-

25. An internal combustion engine having a carburetor for its fuel, characterized by the fact that the side of 'the piston-is provided witha passage to direct liquid fuel tending to pass the'piston, to a portion of thepiston nearer its axis-where the fuel issubject to greater heat to vaporize it.

26. In an internal combustion engine, the combination of a hollow engine piston having a passage for passing into the spacewithin the guiding skirt of the piston fuel;tend-' ing to pass the piston, and meansfor sucking fuel from within the skirt and returning it to a combustion space of the engine;

27-1w an internal combustion engine the combination of a hollow engine piston having a passage for'passing into the piston fuelv tending to pass the piston, the piston-being porized, and means for withdrawingthe fuel vapor from withinthe it; to the engine.

In testimony whereof, I have signed this specification.

. RUSSELL S. CARTER adapted to retain the liquid fueluntilivapiston and returningv