US 1649700 A
Description (OCR text may contain errors)
y I Nov. 15, 1927.
F. JOBES INTERNAL COMBUSTION ENGINE Filed April 23, 1924 3 Sheets-Sheet 1 Nov. 15, 1927. 1,649,700
INTERNAL COMBUSTION ENGINE Filed- April 25, 1924' s Sheets-Sheet 2 mlllllll" mayo/d Z I gwu roz azwfi y Nov. 15, 192 7.
F. MJJQBES INTERNAL COMBUSTION ENGINE Filed April 23, 1924 3 Sheets-Sheet 3 mw h M Z2 W 8 Patented 1 5 i uui frsn STATES sm: u some, or ANN Anson, MICHIGAN.
A ucauonmea A ril as, 1924. Serial No. 70s,57 5.
This invention relates to internal combustion engines, and more particularly to internal combustion engines of the constant yolume type adapted to be operated on gaso- 5 line or other li ht hydrocarbon fuels.
An object of tliis invention is to materially increase the thermal efficiency of such engines v Another object of this invention is to maintain substantially the same efliciency throughout the full throttle range of an infternal'combustion engine.
A further object of this invention is to secure in a constant volume type of internal combustion engine a high maximum, mean eiiective pressure in the cylinder in order that" the power output maybe high in proportion to the piston displacement.
A still further object of this inventionis 2" to provide means to prevent'detonation at all engine loads in an internal-combustion engine having a higher than normal compression pressure;-
It has long bQBIYlKIIOWIl that the thermal efliciency of an internal combustion engine depends directly upon the expansion ratio, which is limited to a t extent, by the compression pressure 0 the engine. While this desirable theoretical condition of cfficieney can be gained in practice to some degree, the expansion ratio is materially limitedbythe relatively low compression pressure under which. the ordinary en ine may work, for it has been determined t at above the usual pressures, a peculiar condition of combustion develops especially when using an explosive mixture composed of li ht hydrocarbons orsimilar fuels mixed with air. When such a fuel is highly com ressed 40 and ignited a phenomenonknown as etonation takes place in which the rate of combustion increases abnormally, making it'sub stantiallyan instantaneous process, and r0 ducin a characteristic knock in the com ustion 0 amber. Operation of a motor under these conditions results in rapid overheating.
to such an'extent that it is impossible to 0perate it for an eat length of time or with a high therma e ciency. In order to secure x a higher thermal efliciency, itecomes nece ssary to provide means for cntrolling thls phenomenon, and much attention has been an engine is-fuIly describe in my copendling detonation, the use of inert gases mixed devoted in recent years to the solution of this problem, butin general the various solutions put forth have proved to be complicated or' unreliable commerciall Experimental work has demonstrated that therate of combustion in the cy-linderof an internal combustion engine may be me.- terially decreased by addin to the combustible mixture a quantity 0 inert gases, an abundant supply of which is to be found in the products of combustion from such anengine. By providing means to properly proportion the diluent to the mixture, at the fuller throttle loads, it is possible to design an engine having a considerably higher compression ratio than is permissible when no detonation control is effected. The 0 oration of such an engine is fully describe in my copending application, Serial No. 669,173, filed'Oct. 17, 1923.
It has also been demonstrated experimentall that when a small localized charge of com ustible mixture having access to 'a large volume of pure air or excessively lean mixture .is burned under pressures which ordinarily cause detonation, the effects of such detonation are absent, and it is there fore permissible to use in en ines operating in this manner, a considerab higher com-H pression-ratio than is otherwise found rmissible. En 'nes of this ty have 11 built, butoit as been'determined that the maximum power output is unusually low 86 owing to the difiiculty of rapidly and completely intermingling the localized char e with the large volume of air, during the sma 1 period devoted to combustion, as is necessary in order to secure the complete burning of Q a mean nearnormal mixture for the produc-- tion of a high maximum power output at full throttle loads. The 0 oration of such ing applicationy Serial No, 696,878, filed Mar. 4, 1924., I
This invention includes a combination of the two above mentioned means for controlwith the combustible mixture being restricted to the fuller throttle loads, whileat the minimum and intermediate loads, a 10- calized charge of rich combustion mixture is burned w1th access to a large volume of:
pure air or lean mixture, with which it may intermingle during the process of combustion.
A highly satisfactory type of engine is provided b such acombination of control means, ma ing it possible to design an engine having an unusually high compression ratio, which will operate without a trace of detonation, and in which there is also secured the valuable features of a constant compression ratio at all throttle loads, thus maintaining full efliciency throughout the throttle range. This latter feature is due to an arrangement which provides that onl a small char e of combustible mixture 1Sr drawn into t e compression chamber and retained in an isolated portion thereof, there being admitted a volume of pure air suflicient to fill the remainder of the compression chamber at substantially atmospheric pressure. Thus, even at reduced loads, the small combustible charge is compressed to the same pressure as the charge at full load, which pressure is materially higher than permissible in engines not including detonation controlfThere isalso provided means for securing 'a high degree of turbulence of the pure air contained within' the combustion chamber during the compression and expansion strokes, which is an effective solution of the problem of securing a high mean effective pressure in an engine which may be considered to belong to the partially localized charge type.
For a full understanding of this invention, reference should be had to the accompanyin sgaecification taken with the drawings, in w Figure 1 is'a transverse section through the upper structure of one cylinder of an internal combustion engine, constructed ac cording to this invention;
Figure 2 is a partial plan view of the en ne with parts broken away;
igure 3 is a schematic diagram showing the path of the inert gases;
Figure 4 is a side elevation part1 in section of a modified form of device or regulatjlng the flow of inert gases to the cylinder; an
Figure 5 is a longitudinal section through the combined expansion chamber and cooling device for the inert gases.
In Figure 1, the usual cylinder 10 is shown fitted with a piston 11 of well-known form and connected to a crank shaft (not shown) bymeans of a connecting rod 12 and wrist pin "13. The cylinder is surrounded bv a water jacket 14 for cooling urposes. The upper end of the cylinder is c osed by means 0 a c linder head 15 which includes the dome-s aped combustion'chamber 16, offset from but communicating restrictedly with,
the upper end of the cylinder through the passage 17 the pocket 18 communicating restrictedl with the combustion chamber through .t e assageway 19;the spark plug or ignition evice 20; the water jacket 21 and the combustible mixture inlet manifold 22.
Arranged beside each cylinder in the manner common to the usual type of L-head motor, is the inlet valve 23 and the exhaust valve 23'. These valves are retained on their seats by the usual valve springs 24 and opened in the well-known manner by cams such as 24 mounted on a cam shaft driven from the crank-shaft. These valves open into the combustion chamber 16, and the exhaust valve controls a passage leading to the usual exhaust manifold 25, while the inlet valve 23 controls a assage 26 leading to a manifold 27, which is open at one end to the atmosphere as shown at 27.
The portion 28 of the cylinder head extending above the piston has merely suiiicient clearance 29 at top dead center for safety, so that at the completion of a compression stroke, all the gas contained between the portion 28 and the piston head, is violently projected into the combustion chamber 16 through the restricted opening 17, thereby causing a high degree of turbulence within the chamber.
The isolated pocket 18 is of comparativelysmall volume compared with the volume of the combustion chamber 16, and the assageway 19 is restricted, directed away rom the piston and shaped somewhat as a Venturi tube in order that the products of combustion issuing therethrough may more readily interminglc with the air contained in the combustion chamber 16. The upper end of the pocket 18 is normally closed by a spring controlled valve 30 fitting upon a seat 31, which is integral with the valve cage 32. This cage is suitably inserted, preferably by threading, into the pocket 18 and contains a valve guide 33 mounted on the'spider 34. Between it and the washer 34, on the end of the valve stem, there is a spring 35 normally tending to retain the valve 30 against the seat 31. The upper end of the valve cage is closed by means of a cap 36, while the manifold 22 communicates with the interior of the cage. A carburetor, 22 having an induction tube 37 is adapted to be attached to the manifold 22, and is provided with the usual butterfly throttle valve 38 mounted on a shaft 39 which is adapted to be rotated by means of the arm 40.
This carburetor may be of relatively small size compared with the size of the engine to which it is attached, and is normally ad justed to deliver an extremely rich "com bustible mixture to the pocket 18 of the engine.
gases to the cylinder, there is provided In order to provide a supply of inert Ill" means, attached to the air manifold 27 and 139 projecting therein near the air inlet, for the admissionof such gases. The hollow casting 41 is adapted to be bolted tothe intake manifold 27 and has. in its upper end an aperture 42 through which a boss on the. casting 43 is adapted to project.- This caste ing 43 is rigidly secured to the patt 41 and circular recess 47 with .the vertical 'bore 43.
contains a vertical circular hole 43 passing completelythrough it. Into the lower endof this hole is fitted the nipple 44 having the end bent at right angles so that it forms a horizontally projecting jet 45. A passage 46 extends transversely into the casting 43 and communicates by means of an enlarged To provide means to control the amount of gas flowing fromflthe passage 46 to the bore '43, there is provided a hollowtubular member 48 closed at its upper end and having a working fit in the bore. Arranged between the lower end of the tubular'member 48 and the nipple 44 is a coiled spring 49 normall retaining the tubular valve member 48 in the position shown in Fig. 1, so
" 55, to the arm and at 56 to an, extension 57 on the cam. The portion connectedto the ham is tubular and internally threaded to fit corresponding external threads on the rod-portion, so that the relative positions of the arm 40 and the cam may be adjusted byv withdrawing the pivot 56 and screwing the tubular portion on or of! of the rod, the lock nut 58 being provided to maintain the adjustment fixed The cam 51 is substantially circular in form,concentrically mounted'about the pivot.52 ,'buthason the side opposite the extension 57 a lobe 59 which is so positioned as to contact with the rounded upper end. of the tubular valve member 48 when the throttle valve 38 is opened to a position corresponding to considerably more than one half load of the engine, and from thereon the member 48 is progressively depressed as the throttle is opened to its maximum position. I
In order toobtain a satisfactory. quantity of inert gases .under the proper conditions, it has been found desirable to withdraw an excess amount from the exhaust manifold and allow them to pass into an expansion chamber where the excess quantity is exhausted to the air, the remainder passing through a cooling device before being led into the passage 46. Such an expansion hollow tubular casing 60 is closed by heads- 61 and 62, each provided with a'nipple for the attachment of a pipe. This-chamber is divided into two main portions by means of an integralwall 6'3, andthe upper chamber formed thereby is divided into any suitable number of compartments, shown asfour, by means of the perforated ,baflieplates 64 spaced by springcollars 64. The
wall of the largest one of these compar-t- I ments is provided with a series otexhaust ports 65-whereby the excess gas inay bebar- I ricd away to the atmospheres-The spacing collar is perforated to register with.v the ports 65 and is pr vented fromrotatingby the pin'65'. The wall 63 and a similar-wall 66 near the lower end ofthe casing are provided with perforations into which are tightly fitted a series of longitudinal tubes 67 connecting the upper compartment'of the chamber with a small lower compartment .68
leading to the outlet thereof. Water is adapted to be circulated around the tubejs67 within the compartment 69, and there is shown at 70 an inlet and at 71 an-outlet for such cooling water which may be conveniently taken from the radiator 'of the in ternal combustion engine.
. Figure 3 shows the manner in which the expansion and cooling device is connected between the two manifolds, the path of the gasesibeing indicated 'by the arrows. The gases from the exhaust manifold 25 pass through a pipe or'tube 72, enter the upper end of the combined expansion and cooling device 60 where they are expanded in the upper. compartment, the excess gases ex hausting through the openings 65, and theremaining gases passing down through the tubes 67 which are surrounded by the cool ing water, where they are cooled: before I passing out through the pipe 73 and enteringthe passage 46. When 'thetubular valve member 48 is depressed by the cam lobe 59,
the openings 50 therein register-with the cavity 47 connected to the passageway 46 and-allow the cooled exhaust gases to-pass' within the tubular valve member and out through the jet 45 where they intermingle with the in of the inlet manifold 27. v
n Fig. 4, there'is disclosed a modified form of device for regulating'the amount of inert gases which are admixedwith the pure.
pure air taken in through the open-l 2 air flowing in the inlet manifold. The cas-i." 'in 75 has a right angled elbow at the lower en and is adapted to be bolted against the side ofthe cylinder so that its bore 7 6 com- I municates with the passage 26. leading to the inletvalve 23. The v'erticaltubular por-' tion 77 is provided with an aperture 78 through which atmospheric air is taken. The bore 79 in the upper'end of the. member an E on I
75 is closed by means of a casting 8 hav ing a boss 81 fitting into the opening and ing the bore 82 transverselyis the passage 85 having threaded therein the nipple 86 adapted to be attached to a pipe leading from the expansion and cooling device -pre viously described. The junction of the passage 85 and the bore 82 is enlarged at 85- and the upper end of the passage 82 is pro-- vided with a valve seat adapted to coopcrate withthe tapered point of a threaded valve plunger 88 having a knurled head 89 for ease in manual adjustment. The threaded portion 90 of this valve stem engages an internally threaded portion of the casting 80, and it is'retained against movement and leakage by means of.-a packing 91 compressed and retained in position by the packing nut 92 having suitable threaded engagement with the reduced upper end of the casting 80.
While the method of operation of the modification shown in Fig. 4 is'considerably different from that disclosed in connection with Fig. 1, yetthe results obtained are substantially the same for the following reasons. In an engine of the constant'compression lo-- calized charge type, the percentage of the products of combustion mixed with pure air in the exhaust. is directly proportional to the engineload. Hence with a fixedsetting of the valve, 88- a. substantially constant volume'of exhaust gases enter through the 'et 84: and mix with the 'pureair admitted .-t0 the cylinder through the mentioned intake valve but-at extremelysmall engine loads the actual products of combustion mixedin these exhaust gases-are very small dueto thesmall" amount ofcombustible mixture burned in the cylinder, with a large amount of air, but as t e: engine load increases the percentage of the products of combustion also increases so that at iull engineloa'd the of engine. By means of manual regulation of the valve-plunger 88 the amount of inert gems admitted can be regulated so ,that just,
' the proper. amount is obtained at maximum load to prevent detonation.
While it is most desirable to expand and cool the products of combustion before they are intermingled with the intakeair, quite satisfactory operation can be obtained without this procedure although the volumetric eflicienoy of the engine will be somewhat lowered owing to the expansion of the intake air due to its being heated by the products of combustion resulting in. a smaller actual quantity of air being taken in, which of coursematerially reduces the compression pressure within the cylinder resulting in a reduction in power.
Operation. The operation of an engine constructed according to this invention may best be understood by tracing its cycle of operation at minor, intermediate and maximum engine loads. In each case it will be understood that the engine is considered to be ready to begin its intake stroke.
At minor engine loads, the carburetor throttle valve 38 will be in a closed or nearly closed position and as the piston moves down'through the first fifteen totwenty percent of the suction stroke the main inlet valve 23 and the exhaust valve 23 previously mentioned remain closed under the action of the valve springs 24 so that a negative.
pocket 18,. It will be understood that this charge of combustible mixture is exceptionally vrich and is of a quantity insuificient to fill the pocket 18. Upon the completion of the mentioned interval of the intake stroke the air inlet valve 23 is opened under the action of its cam 24;, allowing during the remainder of the intake stroke of the piston, a large volume of air to flow into the combustion chamber, the rich mixture receding into the pocket and allowing the valve 30 to close since the negative pressure is materially reduced by the opening ofthe large air passage to atmosphere through the valve 23. At the end of the intake stroke, the valve 23 is closed and the usual compression stroke follows'immediately, the peculiar shape and offset position 'of the combustion chamber 16 causing a high degree of turbulence of the air which. is rapidl transferred from the cylinder to the com ustion chamber and at the same,time causing considerable turbulence within the pocket 18 due to the restricted size and peculiar shape of the opening 19. It should be noted that at the completion of the compression stroke the air contained between the piston head and the overhanging portion of the cylinder headis violently pI'0]eCt8(l through the opening 17 into the combustion space 16 in such a manner that it sweeps the walls of this space and causes a somewhat circulardnotion of the air within the chamber 16. r Upon the completion of the compression stroke the charge or combustible mixture within the pocket is is fired by the spark .plugJ2O, and assisted by the high degree of tar ulence within the pocket, the rate of flame propagation is very rapid and the, heat liberated due-to the com bastion causes a rapid expansion of the gases I resulting in the passage ofa large part of- I the-gases projected out through the opening them out of the pocket through the Venturi shaped opening 19 into the excess air filling the combustion space 16 where they are violently intermingled with the air. At this point it will be well to consider that all of 19 are not in a process of combustion, but
some are. rather unconsumed particles adv'ancing before theexpanding flaming. mix.
ture which is ignited near the rear portion or the pocket 18,- and some of the projected flaming mixture is incompletely burned due to the richness of the mixture as admitted to the pocket 18.- 'These unconsumed particles areswept away by the turbulent air'in the combustion chamber and intermingled with it thereby forming an extremely lean mixture which is ignited by the high temperature and pressure'of the projected-flaming mixture resulting in complete combustion of said formed extremely lean mixture with no trace of detonation. Following this initial combustion the usual expansion stroke of the piston occurs, the first movement of the piston away from the wall 28 creating a vacuum into which. the burning gases are immediatelydrawn. aiding in the turbulenceand so promoting the rapidfiame propagation. At any desired point in the expansion. strolre the exhaust valve maybe opened by its cam as is well known in the usual types of internal combustion engines,
the exhaust valve opening occurring before the completion of the expansion stroke ln order to reduce the'pressure within the cylinder to atmospheric before the beginning of theexhaust stroke in order that there may be the 'least possible amount of back pres-- sure.
It is essential-to the satisfactory operation ofan engine of thetype disclosed that the charge of richcombustible'mixture be maintained substantially isolated during the intake stroke, from the large volume'ofair ad'- mitted duringthe'latterpart of that stroke until the engine load increases to the point where the temperature and pressureof the combustion are sufliciently'high to insure the complete combustion of any excessively lean mixture that mightbe formed by admixture-- of any part of the rich charge carriedout of the pocket and intermingled with the air admitted during the intake stroke The,
above results may be best' obtained by using a small carburetor-of the conventional type adjusted togive a mixture of the desired richness in combination with a pocket 18 large enough to hold the entire volume of.
' put is increased from minimum to a certain critical value by increasing the volume of mixture, maintaining it at a near constant strength and constructing the pocket 18 large enough to contain all of this mixture up to that critical load, Another possible method of control permits the use of a some-. what smaller pocketinto which is admitted at below the critical engine load a constant volume of mixture just sutlicient to fill the pocket, and in order to increase theengine power the richness of the charge is increased vfrom'nznnimum up to the point of critical load after which an increasing volume of nearl constant richness is admitted, an in.- creasin volume of which is carried out of the'poc st and mixed with the air until at full engine load a combustible mixture only slightly lean is built up in the combustion chamber. This latter condition is also duplicatiad in the first mentioned method of contro r The operation of the engine at intermedi-.
ate loads above the critical ,point previously mentioned begins with substantially the sameoperation as previously described, but there 1s of course a larger volume of combustible m1xture taken into the oclret 18 due to the Wider opening of the t rottle 38, and some of thismixture overflows into the combustion chamber 16 where it is quickly swept awayfrom' the mouth of the ocket by the turbulent air within this com ustion chamber.-This is again repeated at the completion of the compression stroke so that there is, formed a very uniform lean mixture with in the combustion chamber. These opera-.
tions cause within the 1pocket 18 the turbu lent condition previous y mentioned so that upon ignition the previously described op-- erations take lace, the flaming mixture issuing through t e passage 19 igniting the extremely lean mixture within the combustion chamber 16, but contrary to the usual practice, combustion of this lean mixture is very ra id andcomplete owin to the hi d ee of turbulence and high gressure mii ntifi h ed within the combustion chamber. The remaining o erations are substantially identical with t ose previously described.
'At full engine load the operation of the engine is ulte similar to that taking place at interme iate engine loads, but a larger volume of the rich mixture issues from the port 19 and is commingled with the air in the combustion chamber 16 forming a mixture only slightly lean which is com ressed with the usual turbulence in the com ustion chamber as previously described. As the strength of the mixture thus formed apg is forced into thepocket 18 where it mixes proaches that of a normal mean mixture the conditions giving rise to detonation are present making it necessary to provide an additional means for controlling or preventing it, and by reference to Fig. 1 it will be noted .that as the throttle reaches a position corresponding to that of approximately full load the link 54 rotates the cam 51 so that the lobe 59 contacts with and depresses the slidable valve member 48 to a position where the apertures 50 therein register with the circular enlargement 49 and allow the products of combustion to flow from the jet 45 and in termingle with the intake air in the correct proportion to prevent such detonation. Thus at the higher engine loads the mixture formed within the combustion chamber is diluted with the necessary inert gases i. e. the products of combustion, to control the increasing tendency to detonate. A similar result is attained by the use of the modification shown in Fig. 3 as previously explained. Upon conclusion of the intake stroke the charge is compressed into the combustion chamber and pocket 18 and fired as'before.
Since during the latter part. of the intake stroke, air diluted with the products of combustion is being admitted, and since the air admitted earlier in the stroke has already swept away a large portion of the excessively rich mixture issuing from the port 19, then at the completion of the intake stroke there is a quantity of air outside ofthis port which at the beginning of the compression stroke therein, and necessary to complete its combustion is provided. Owing to the high degree of turbulence set up through the early part of the" expansion stroke by the rush ofgas out of the chamber -16 to fill the-space evacuated" by the descending piston,'a further discharge of the flaming mixture out of the pocket is induced by the decreasing pressure within the combustion chamber as the volume occupied by the gases is so enlarged. This condition favors the rapid commingling of the gases so that their further combustion progresses throughout the early part of the power stroke. .At this point. it is well to note that the highest possible maximum power output from an engine of this type may be secured by adjusting the strength and.
volume of'the rich mixture retained within the isolated pocket so that only a mean normal mixture is formed therein at the completion of compression and so that the commingling of the charge carried out of the pocket duringthe intake stroke with the .air later admitted is such as to form a nearly mean normal mixture, diluted with the necessary products of combustion to prevent detonation when compressed into the combustion chamber 16. j
Since.- this invention is mainly concerned with the power cycle'of an internal combustion engine, there has not been. shown nor.
described any of the means for. operating the valves nor for drivin the cam shaft or lubricating the engine, an it is to be' understood that any suitable methodsfor obta ning the, desired results along these lines may be used, and it is not desired to restrict the engine to any particular type of valves such as the poppet valves shown, for it may be readily seen that the same results may be obtained with rotary, piston, etc. type valves,
and that the particular position of the valves is of little consequence, as it is evident that the exhaust valve may be arranged in the head directly over the inlet valve, and vice versa. It niayisometimesbe desirable, especially in high speed engines of this type, to
provide mechanical meansfor opening the rich mixture intake valve 30,, and in such cases it is evident that the air inlet valve 23 may be timed to open during the entire intake stroke and the timing of'the mechanically operated valve 30 may be arranged to open said valve through a suitable fraction of the first part of the intake stroke sufiicient to permit the flow of the rich charge to the pocket 18. It is also evident that when mechanical operation of the valve 30 is used that a carburetor having no throttle valve may be used and the engine throttled' (its power output varied) by using means such as a longitudinally adjustable cam shaft having thereon conical tapered cams to operate valve 30, these cams in their various possible positions engaging to open the valve 30 "for varying fractions of the intake stroke, so that the volume of charge admitted to the pocket may be varied from only sufficient for idling purposes to that excess over the capacity of the pocket necessary to form the previously explained admixture with the air admitted at full engine loads. In such a modification,-there may be interlinkage be tween, the means shifting the camshaft lon-- gitudinallyv and the cam disc v51 so that the products of combustion maybe added to the charge substantially as described for the illustrated. modification. The engine would otherwise operate substantially as described for the present modification; It is also evident that the passage 19 -ma.y."be formed from a suitably shaped bushing pressed into thecylinder head so that the Venturi shaped passage passing centrally through the bushing may occupy the same relative position.
as illustrated. This passage 19 should also be asshort as posible and yet secure the isolation of the charge contained within the pocket from the air admitted to the combustion chamber during the intake stroke. It is also evident that when this invention is adapted to a' two cycle engine, means may e provided for pumping the charge into the pocket 18 and the air into the combustion chamber.
It is also to beunderstood that an engine operating substantially as explained in the previous part of this specification up to engine loads permitting the forming of an admixture of a part of the charge admitted to the pocket and the air admitted to the combustion chamber, but forming a lean mix- 18, to at near maximum loads supply a mixture decreasingin richness until at full load the mixture supplied would be normal in strength and to adjust the admixture of mixture and air in the inductance (air) passage'so that at full engine load a normal completely combustible mixture would be so formed by admixture. Thus at full engine.
load a normal mixture diluted with the products of combustion necessar to prevent detonation would be burned. .T e modification of a carburetor to function as described could be very readily carried out one number of conventional type carburetors, or if desired a new carburetor might be designed to so function. k e
In modifications of this invention, it may be found that with engines designed for various duties (some requiring high speed operation, some lowi and etc.) the most suc-- cessful operation wi 1 require various timing of the valve mechanism controlling the admittance of the rich charge to the pocket 18 and it is therefore evident that itshall fall within the scope of this in'ventionto' vary such timing considerable from that s ecified in reference to the illustrated modi cation.
In withdrawing products of combustion from the. exhaust manifold in any modifica-' tion, it is preferable that they be Withdrawn as remote from the exhaust port of the en gine as is convenient so that their temperature be as moderate as possible.
It is also to be understood that he capacity of the passage 17 shallordinarily be I at least equivalent to that of the air passage not limited to this modification, for it isa obvious that the same results may be obtained by various means, the preferred form of which has been disclosed, but it is to be understood that this invention shall be limitcd only by the appended claims.
Having thus described my invention what I claim as new and desire to be secured by Letters Patent is:
1. In a high compression internal combustion engine, a cylinder, a piston therein, a combustion chamber offset from, but communicating with said cylinder through a reduced passage, a pocketv communicating with said combustion chamber through a restricted opening, means to supply a combustible mixture to said pocket, an ignition device in said pocket, an air intake valve communicating with said combustion chamber and means to supply -avariable quantity of inert gases dependent upon engine throttle load, through said air valve.
2. In a high compression internal combustion engine, a cylinder, a piston therein, a combustion cham e r offset from, but communicating through a reduced opening with said cylinder, the end of said cylinder being otherwise closed by a cylinder head substantially engaged by the piston at top deadcenter, a pocket communicating with said combnstion chamber through [a restricted passage, a carburetor connected to said pocket to supply combustible mixture thereto, an ignition device in said pocket, an exhaust valve in said combustion chamber, an inlet valve therein, means for operating said valves, a. manifold leadir to said inlet valve and open to the atmospere, a jet in said manifold and means to supply inert gases to said jet in proportion to said engine throttle load. 3. In a high compression internal oombus tion engine, a cylinder, a piston therein, a combustion chamber offset from, but communicating through a reduced opening with id cylinder, the end of said cylinder being 0 herwise closed by a cylinder head substantially engaged by the piston at top dead center, a pocket communicating with said combustion chamber through a restricted passage, means for supplying an excessively rich combustible mixture to said pocket during the initial part of the intake stroke, an intake valve controlling a passage to a manifold open to the atmosphere, means to open said intake valve'after the initial part of the intake stroke and means for supplying inert gases to said manifold in suificicnt quantities to prevent detonation at all loads.
4. In a high compression internal combustion engine,a-cylinder, a piston therein, a combustion c ber oitset from, but communicatingcthrolrgh a reduced opening with said cylinder, the end of said cylinder being otherwise closed by acylinder head substantially engaged by the piston. at top dead center, a pocket communicating with said combustion chamber through a restricted passage, means for supplying an excessively rich combustible mixture to said pocket during the initial part of the intake stroke in suflicient quantity to overflow said pocket at large engine throttle loads, means to complete the filling of the cylinder with air to mix with said overflow forming within the combustion chamber a substantially normal combustible mixture means to dilute said mixture with inert gas in proportions to just prevent detonation, an ignition device in said cylinder and an exhaust valve.
5. In an internal combustion engine having a compression pressure'above that required to produce detonation, a cylinder, a combustion chamber, means to supply an excessively rich combustible mixture to sa 1d combustion chamber, means to supply air in a, turbulent state to said combustion chamber, means regulatingthe admixture of said air and combustible mixture in accordance with engine throttle load, ineansto ignite said combustible mixture inan isolated .portion of said. combustion chamber, and means to prevent detonation at higher engine loads by proportionately "diluting said air with products of combustion.
6. In a'high compressiomconstant volume internal combustion engine, a cylinder, a piston therein, a combustion chamber offset from, but communicating with said cylinder through a reduced opening, the end of said cylinder being. otherwise closed by a cylinder head substantially engaged bythe piston at top dead center, an exhaust valve, an intake valve communicating with an intake manifold open to the air, a jet opening into said manifold, valve controlled means to supply cooled products of combustion to said manifold, a pocket communicating through a re stricted opening with said-combustion chamher, an ignition device in said pocket, a valved port opening into said pocket, means to supply an excessivelyrich mixture to said pocket in insufficient quantity to fill said pocket at engine throttle loads less than those giving sufiicient temperature and pressure of combustion to insure a complete combustion vof any excessively lean mixture formed by a part of the excessively rich combustible mixture charge and gases ad'- mitted through said intake valve to the combustion chamber, and in sufiicient quantity to form by such admixture an only slightly lean mixture in the combustion chamber at maximum engine throttle loads, and means for simultaneously controlling the amount of charge and the proportion of products of combustion admitted.
7. In a high compression internal combustion engine, a cylinder, :1 piston therein, a combustion chamber offset from, but communicating thru a reduced opening with said cylinder, the end of said cylinder being otherwise closed by a cylinder head substantially engaged by the piston at top dead center, a pocket communicating with said combustion chamber thru a restricted assage, an ignition device in said poc et, means to supply said pocket with an exces' sively rich combustible mixture during the nearly part of the intake stroke, means supplying to the combustion chamber, during the remainder of the intake stroke, substansure complete combustion of any lean mixture formed in the combustion chamber due to the admixture of overflow combustible mixture and air, an exhaust manifold, means to cool and expand a portion of the products of combustion therefrom, means to conduct said products to the combustion chamber and means to regulate the quantity so admitted in proportion to the throttle position,
8. In a high compression constant volume internal combustion engine, a cylinder, a iston in said cylinder, a combustionchamiier offset from but communicating through a reduced-passage with said cylinder, the end of said cylinder being otherwise closed by a cylinder head substantially engaged by the piston'at top dead center, a pocket, communicating with said combustion chamber through a restricted opening, a spark plug in said pocket, a valve in said pocket, :1 carburetor connected to said pocket through said valve, a throttle valve between said carburetor'and pocket,-an intake manifold open to'the atmosphere for said cylinder, an exhaust manifold for said cylinder, a valve be- .tween each manifold and the cylinder, a connection between said manifolds, and expansion'and cooling device in said connection and means dependent on throttle position for re lating the flow of exhaust products throug said connection. 1 9. The method of operating an' internal combustion engine comprising, admitting to the combustion chamber during the intake stroke successively a volume abnormally rich combustible mixture and a large volume of air, maintaining the mixture substantially isolated from the'air during intake and compression at low engine loads, and at higher engine loads formin a readily i itible admixture of pa t of't e combusti le mixture and the air, a dingto this charge a determined quantity of expanded and cooled products of combustion to prevent detonation, compressing the charge, igniting first the rich combustible. mixture, expanding the products of combustion throughout the during the ex us stroke.
10. The met of operating an internal combustion engine comprising taking into the combustion chamber successively during the intake stroke aco ntrolled quantity of excessively rich combustible mixture and a large volume of air at times diluted with cooled products of combustion, maintaining the charge of combustible mixture substanbut communicating through a reduced opening with said cylinder, the end of said cylinder being otherwise closed by ahead substantially engaged by the piston at top dead center, a pocket communicating with said combustion chamber through a" restricted passage, an ignition device in saidpocket,
means supplying said pocket with a controlled volume of excessively rich mixture during the early part of the intake "stroke, an
inlet ,valve controllinga passage from said combustion chamber to the atmosphere, and adapted to positively open late during the usual intake stroke, means isolating the charge of rich mixture admitted to said pocket from the gases admittedto said combustion chamber by said inlet valve during the intake stroke at engine throttle loads below those giving temperature and pressure of combustion suflicient to insure the combustion of any lean mixture formed by admixture of apart of the rich charge carried out of the pocket and intermingled with ases admitted to thecombustion chamber t roughsaid inlet valve, forming at engine loads insuring the combustion of a lean mixture formed by admixture of said rich mixture carried out of the pocket and the gases admitted to the combustion chamber through said inlet valve, a lean mixture increasing in richness until at full loads an only slightly lean mixturejs so formed, an, exhaust valve assage opening into said combustion and cham er, said exhaust valve being adapted to positively open said exhaust passage durin the usual exhaust stroke, and means adapted to supply to said combustion chamber products or c mbustion. Suflicient to c nated from the air during the intake trol detonation at near maximum engine loads.
12. The method of operating an internal combustion engine comprising taking into the combustion chamber during the intake stroke a large volume of air and a controlled volume of rich combustible mixture,
the latter being admitted during the early part of the intake stroke, maintaining th charge of rich combustiblefmixture substantially isolated from the air admitted during the intake stroke at engine throttle loads up to that insuring the complete combustion of any lean mixture formed by admixture of a part of the charge of rich mixture and the large volume of air admitted to the compression chamber, forming during the intake and compression strokes, at engine loads above the critical mentioned, by admixture of a portion of said rich charge and the air admitted to the combustion chamber, a lean mixture increasing in richness until at full throttle loads an only slightly lean mixture'is so formed,- diluting the air admitted with products of combustion in quantities just suflicient to. control detonation when the engine is heavily loaded, compressing the charge, igniting the rich charge when compressed, expanding the ignited charge and exhausting it.
13. In a high compression internal combustion engine the combination of a cylinu der, a piston in the cylinder, a combustion chamber offset from, but communicating through a reduced passage with saidcylinder, the end of said cylinder being otherwise closed by a cylinder head substantially engaged by the piston at top dead center, a pocket communicating with said combustion chamber through a restricted opening, an
ignition device in the pocket-,valved means supplying said pocket with rich combustible mixture in quantities insuificient to fill the pocket at low engine loads and in a large excess over the capacity of the pocket at full engine loads, an intake manifold open to the atmosphere, a valve between said cylinder and said manifold adapted to connect the two during-the latter part of the usual intake stroke, an exhaust manifold for said cylinder, a valve between said manifold and i said cylinder adapted to connect the two during theusual exhaust stroke, a connection between said manifolds, and means positively controlling the flow of products of combustion through said connection so as to supply to said intake manifold a quantity sufficient to control detonation only at near maximum engine throttle loads.
14. In a high compression internal combustion engine the combination of a cylinder, a piston therein, a combustion chamber ofiset from, but communicating through a reduced opening with said cylinder, a pocket communicating withsaid combustion chainher through a restricted passage directed at an angle away from the piston and sometion chamber so that air only is supplied to the combustion chamber until the engine throttle load becomes great enough to insure complete combustion of any lean mixture supplied to the combustion chamber, means to allow the exhaust gases to pass from the combustion chamber during the usual exhaust stroke, means adding to the charge admitted to the combustion chamber sufficient prod-' nets of combustion to control detonation only at near maximum engine throttle loads. In testimony whereof I hereunto aflix my signature.
FRANK M. JOBES.