BE728429A - - Google Patents

Description

  

    <Desc / Clms Page number 1>
 



  'Stratified feed motor'
The present invention relates to a reciprocating piston type internal combustion engine with a layered fuel system which provides stratification of the feed for complete combustion of the fuel in the cylinder which serves as the combustion chamber. and, more precisely, to an internal combustion engine of the Otto cycle type for

  <Desc / Clms Page number 2>

 spark ignition of the air-fuel mixture, in which combustion of the stratified feed is carried out, i.e., a stratified feed of an easily ignited combustible mixture is burned in the vicinity of the region including the spark plug.



   Attempts to improve internal combustion engines, especially gasoline ones. have so far aimed at a greater power flow and a higher thermal efficiency, as well as an improvement of the mechanism. When it comes to eliminating the portion of the air due to tailpipe emissions, manufacturers have simply relied on certain accessories for the reduction of harmful gases.

   However, emissions containing carbon monoxide, CO, hydrocarbons, HC and nitrogen oxides, NOx, have increased so rapidly in recent years that the limitation and elimination of these harmful hazardous substances for the public or the production of cleaner exhaust gases, has become a problem of paramount importance which must be solved even at the cost of some sacrifice in the output power, thermal efficiency and other characteristics of the engines.



   As is well known, it is important in the combustion chambers of internal combustion engines that the injected fuel, whether in the form of mist or vapor, is suitably mixed with the necessary quantity of air for perfect combustion. . Perfect combustion in engines with an advanced fuel stratification system in the combustion chambers would result in cleaner emissions. If the engines are further equipped with means for purifying the exhaust with some improvement rather than a loss in engine efficiency, then the result would be even more satisfactory.

  <Desc / Clms Page number 3>

 



   It is known that in conventional gasoline engines the concentrations of such noxious gases can invariably be reduced to much lower levels by achieving good combustion of mixtures with sufficiently poor air-fuel ratios for the control of gasoline. dangerous emissions.



   Generally speaking, a decrease in fuel supply relative to a dcnne air intake improves fuel consumption although the engine generates less power. With leaner air-fuel ratios, however, fuel consumption is increased and thermal efficiency is disruptively affected due to slower combustion speeds and greater chances of a faulty ignition. - dO to rarefied and deviated mixtures in each cylinder.

   Thus, fuels burned at excessively lean air-fuel ratios produce only poor thermal efficiency and low power output, and lean blends slow the spread of flame, as a physical phenomenon of an unavoidable nature. The use of a lean air-fuel ratio therefore results in a drop in combustion rate, which in turn results in an increase in exhaust temperature and therefore a possibility of exhaustion. damage to the exhaust valve. irregular combustion cycle, engine malfunction, insufficient power output, poor acceleration and difficulty starting.

   For these reasons, the use of lean air-fuel ratios has not been considered in the past.



   More recently, during attempts to use lean air-fuel ratios, several proposals have been made regarding the stratified fuel system according to which a spark plug is provided in part of the main combustion chamber or in a auxiliary chamber

  <Desc / Clms Page number 4>

 and a gas mixture in the combustible range is formed ignited and burnt and, then, combustion of a leaner mixture in the rest or the assembly of the main cylinder is carried out.

   It is known that in this stratified fuel system, in which the engine is operated with a relatively rich fuel mixture, maintained in the region near the spark plug, and with an overall lean mixture offered throughout the entire process. 'internal space of the cylinder (i.e. with excess air). it becomes possible to improve the specific heat of the active gases so as to more closely approximate a pneumatic cycle, to prevent heat dissociation, and to reduce the loss of heat by cooling to ambient elements. so that improved thermal efficiency and lower fuel consumption can be achieved and.

   furthermore, since the combustion is carried out with a large air supply, the harmful components of the tailpipe emissions can be significantly reduced.



   However, although many versions of the principle of layered feeding have been studied and developed so far, none of them has reached a satisfactory degree of perfection in controlling the harmful contents of exhaust emissions, as well as with respect to utility in actual applications, due to design and controllability imperfections, complexity and other construction problems, etc.

   In particular, it is in fact very difficult to maintain an air-fuel ratio higher than 15 / @, which corresponds (approximately) to the theoretical mixing ratio or @@ between about 16/1 and 17/1 which is generally considered. as feasible .; in each cylinder of the engine and throughout the load range. In addition, the higher the air-fuel ratio

  <Desc / Clms Page number 5>

 and the slower the combustion rate, the higher the exhaust temperature.

   This tends to cause disturbances in the exhaust valve system, increased irregularity of the combustion process, uneven engine operation and frequent occurrence of ignition faults, which in turn results in a difficulty in starting and reduced acceleration. Worse, the air-fuel ratio in this range can increase NOx emission to a maximum.



  If the compression ratio is increased in order to achieve better efficiency, the Nox emission will increase even more. In order to reduce the latter possibility, attempts have so far been made only with some sacrifice in engine efficiency. A delay in the timing of the ignition is an example. However, this results in a reduction in the power output and an increase in the exhaust temperature.



   Recirculating part of the exhaust gas to the intake side is found to be effective, but again reduces the available power and the use of a very rich mixture intended to compensate for the loss of power leads to a increase in CO emissions. Overall, therefore, this approach to the problem does not help clean up the tailpipe emissions.

   Stratification of the power supply is beneficial for improving thermal efficiency for operation at part load, but with ur. engine having to run under full load, it does not ensure good gasification and good mixing of fuel with air so that the engine can deliver sufficiently high power.

     In order for the system to be able to meet the requirements of engines working under a high load, it was necessary to inject the fuel quickly with an injection pump into the cylinder while

  <Desc / Clms Page number 6>

   the latter is completely open and to provide means for adjusting the timing of the injection, which are capable of varying the vaporization and mixing time over a wide range.



   It is almost impossible to prevent the emission of the harmful exhaust components (ie the three components mentioned above) from the combustion chamber, despite these additions. Other disadvantages include an inevitable increase in equipment costs.



   The stratified feed motors designed heretofore not only require expensive accessories of complex design, but present difficulties in obtaining precise and efficient stratification of the feed under all loads. with a lack of stability in the supply obtained and thus they could not offer performance very comparable to those of conventional internal combustion engines.



   According to a version of the stratified supply system, a recess is formed in the crown of the piston and fuel is injected there directly for its vaporization and its stratification.



   This naturally increases the load on the piston, makes temperature control and therefore cooling difficult, and can shorten piston life. In addition, the additional weight which is inevitably given to the reciprocating part due to the special construction hinders the high-speed operation of the engine and makes it impossible to improve efficiency, such as for example an increase in power output.

   Other disadvantages include reduced sweep efficiency, because the recess in the piston head serves as a dead space.
The object of the present invention is to obtain perfectly
1 purification of the exhaust from the combustion chambers of internal combustion engines ;, piston type and reciprocating mocve.;, Without allowing the appearance of harmful components NAss emissions and also allowing an improvement remar-

  <Desc / Clms Page number 7>

 sance provided by the engine and other features.



   Another object of the invention is to eliminate the disadvantages of stratified feed cropping systems which oppose the successful commercialization of the principle and to enable a stratification of the feed to be achieved with conventional engines. mixed in a stable and positive way over the whole load range, without the need for any expensive special accessories, as well as to achieve an improvement in the possibility of ignition, combustibility and the possibility of control - of, all these elements combining to contribute to the improvement of the general efficiency of the engine, in particular with regard to the improvement both of the efficiency and of the durability of operation under full load.



   Another object is to provide an internal combustion engine with a single combustion engine which is defined between the cylinder and the piston and into which fuel is injected directly for efficient charge stratification. so that a desirable mode of combustion is readily obtained by properly taking advantage of the self-circulating property of the exhaust, without imparting any special directionality to the air and inducing any vortex of air around it. the central axis of the cylinder, and also by using the scavenging air current which is produced naturally during the exhaust, supply and compression strokes of the piston,

   to thus obtain in a simple way a combined combustion of the fuel in order to allow the simultaneous control of the three noxious pollutants which constitute a social danger.



   Another object is to obtain operation in a wide range of loads with a poor overall air-fuel ratio by obtaining a stratification of the feed which;

  <Desc / Clms Page number 8>

 can be spread over the rete of the @@ ll @@@@@ @@ ice by the force resulting from a current of coughing air in the combustion chamber of the cylinder and the displacement of a mist from the cylinder. adapted spray nozzle on the cylinder head, thus ensuring additional stability of the argumentation without any attempt to create any special swirling current for the lamination,

   but by injecting the fuel through a swirling air stream having as its basis the sweeping air stream of the loop type and the preservation of its dynamic force in order to form clouds of stratified shape by dispersion, mixing and evaporation and, at the same time, in order to increase the proportion of air on the outer side and to increase the exhaust composition on the inner or concentric side, and in order to maintain this ratio and to perform further an adaptation of the air supply to the combustion process or, in other words, to establish a stable stratified supply by obtaining a rich mixture on the peripheral side and a lean mixture on the concentric side.



   Another aim is to provide an internal combustion engine capable of maintaining good combustion conditions throughout the range from idle to full load operation by injecting fuel from a suitable position and under. an appropriate angle against the sweeping air stream or a swirling air stream based thereon, in the cylinder of an ordinary valveless two-stroke engine, thereby achieving a positive and stable stratified supply which can be spread on the inner surface of the cylinder head by the resultant action of the compound current with the swirling air and the movement of atomized particles. and widening

  <Desc / Clms Page number 9>

 sant the routine tolerance of injection and ignition or firing.

   



   Another object is to provide a stratified fuel engine which eliminates the valve mechanism of an internal combustion engine and which can easily pick up speed without valve flushing, which is otherwise inevitable, resulting in evaporation and cooling due to the direct injection of fuel during the compression stroke of the piston, while reducing the residence time of the mixture in the hot cylinder in order to avoid heating of the intake manifold , therefore by improving the so-called mechanical octane index, which allows an increase in the compression ratio to a fairly high level, so that the engine can offer an efficiency perfectly comparable with conventional engines. in operation under full load.



   Yet another object is to provide an engine of the stratified fuel system in which the ignition or ignition and combustion of the fuel mixture is not carried out simultaneously with the injection of this fuel and, despite the limitation of the octane number, fuel is injected at a certain crankshaft angle before firing or ignition, leaving time for evaporation.

   dispersing and mixing, i.e. using the swirling air stream based on the scavenging air in the cylinder, fuel is injected against this stream from a position suitable and at an appropriate angle to it, so as to form a layered supply spread over the inner surface of the cylinder head by the compound action with the swirling air stream, thereby allowing full using air and making possible the elimination of a smoke limit, a configuration insensitive to poor atomization.

   the time required for fuel injection and firing, improved durability and controllability, improved con-

  <Desc / Clms Page number 10>

 tribution to noise control by omitting the valve mechanism and drive and transmission means therefor, while also obtaining an improvement in the durability and safety of the engine.



   Yet another object is to provide an internal combustion engine of simple and compact construction in which the mass of atomized fuel particles injected into the combustion chamber of the engine is combined under optimum conditions with the purging air stream or the swirling air stream being based thereon, such that the mixture containing the fuel particles can be completely spread over all of the corners of the inner surface of the cylinder head.

   making the best use of the combining action of the mass of the particles with said air stream, while an extension is formed on the cylinder head by protruding towards the purging air stream of such that a thick delineation layer is provided downstream or to produce a zone of turbulent flow by partial removal, so that an appropriate concentration and distribution of the stratified feed is provided and favorable gas flow conditions for flame propagation can be achieved by combining the action of the air stream with any one or a given combination of characteristics formed by the spreading of the atomized particles, the atomized mixture and the propagation of the combustion flame,

   thereby eliminating the drawbacks of high fuel consumption and poor flexibility which have been observed with the conventional homogeneous mixing system, while achieving remarkable improvements in low fuel consumption, flow rate high power and high sensitivity.

  <Desc / Clms Page number 11>

 



   Another aim is to offer at a low cost. an economical stratified feed motor that can be tricky. No-restriction design with a semispherical contour cylinder head to defibrate the combustion chamber and also provide a recess from the inner wall surface to prevent wasteful dispersion of the atomized fuel particles, with the stratification of the feed obtained by the combined movements of the fuel with the sweeping air stream or a swirling air stream based thereon, while being designed to serve as an evaporation section to ensure good setting possibilities. underway, the engine being fitted with a piston which is light and intended for high speed operation,

   so that it can combine the above characteristics with improved thermal efficiency or better average effective pressure in order to contribute to an increase in specific engine power.



   To achieve the foregoing objects, the present invention essentially provides an internal combustion engine of the stratified fuel system which comprises a reciprocating piston, a cylinder providing an exhaust port and a scanning port intended to be opened or closed by the cylinder. displacement of the piston, and an injection nozzle provided in the cylinder head to supply fuel to the cylinder, such that the spray from the injection nozzle mounted in the cylinder head is directed towards the internal surface of said cylinder head against or in a swirling stream of fresh air to provide a combined action for the stratification of the combustible mixture along the surface of the cylinder wall.

  <Desc / Clms Page number 12>

 
 EMI12.1
 a ;:

  aractéristi <rue --- 7portant of the present invention is to provide a; <re. = i O! ': ". b'.l5 ::::' O ¯ner ^ e; 6ponding to? '/ steme <3'alime; tatiJn 3ai: iqu1 as-: co :: ç for ur. loop or cross scan,: = n = or = ton; i.tg C ":": "" .. 5 j =.> r direct '-: ne mass. :: e par- ¯irles finernen-> tJris4-; 1 \ 1e <; r'au = ant tiriide or zon; and of gaseous fuel irlected from an a ;; stage of i.n; ection of fuel stonted to the :: e of cylinder making up a chamber of combustion, in the sweeping air stream or a swirling air stream based thereon or both in the cylinder and
 EMI12.2
 in order to spread, '3ce to' action ccr: .m ^ ée, the fines rt1cu: es or the
 EMI12.3
 gas mixture 5; r # é j vapc3tin a-: a form 'stratified on the internal surface of - -3 * -! * of c ::

   1 i ^ dre, for a ruse to had or a uiterous ignition
Another important feature is the provision of an internal combustion engine of the reciprocating piston type, operating according to the direct injection system, in which a combustion chamber is defined between the head of a cylinder receiving a piston. and the piston head and a squirting flow formed by the inner surface of the cylinder head and the upper surface of the piston head is superimposed and combined with the sweeping air stream or a swirling air stream based on it in the cylinder, so that the gaseous mixture of fine particles of injected fuel and the gas formed by its evaporation can be dispersed, rarefied or concentrated,

   or the draft
 EMI12.4
 receives a flowed or '-mo! t :: rb =: lenc = localized, in order: to thus obtain a state deJ1 = é J'ç: lime: '1t.ri; = ¯ati fied suitable for combustion.

  <Desc / Clms Page number 13>

 



   Another feature of the invention is that the internal combustion engine of the circular or cross-swept type provided comprises means for directing the mass of fine particles injected from the fuel injection nozzle in the head of the cylinder towards a cavity. formed in this cylinder head. thereby dispersing the mass of particles before they are introduced and mixed into the scavenging air stream or the swirling air stream based thereon or both, in the cylinder, such that a fuel mixture can be laminated @ mixed along the cylinder wall.



   Another feature of the invention is that, in the engine provided having an injection nozzle in the cylinder head for supplying fuel to the cylinder, this cylinder head has an internal wall surface with a curved contour, for example. example with a semi-spherical section, and furthermore a cavity is formed in the already curved internal surface.

   means being provided to allow direct injection of fuel from the injection nozzle in the direction of the cavity in order to avoid uneconomical dispersion of the atomized fuel particles and to effect the dispersion and mixing of the fuel with air in this region, as well as stratifying the combustible mixture in the combustion chamber by one or a given combination of the operations of dispersing and mixing, stratified stabilization and transport of the fuel particles by the casing of scavenging air or a swirling air current produced by the reciprocating piston in the cylinder, to then burn the mixture in a stratified state, thus allowing complete combustion.

  <Desc / Clms Page number 14>

 



   In accordance with the present invention, the fuel supplied to the engine is already spread in the region of the cylinder head and possibly entrained by the swirling ar main stream E - since the main stream has a centrifugal force field. . the fuel is displaced under the combined action of centrifugal force and turbulence. Therefore, the induced current of localized airflow accompanying the injection of the mass of atomized fine fuel particles also effectively contributes to the spreading and turbulence actions.

   In addition, the fine particles injected from the nozzle are exposed to the air current flowing at a relatively high velocity, which combines with the gradual increase in air temperature due to the progression of air. the compression stroke to give a good mixture of fuel and air. This mixture circulates on the vortex in the cylinder and is stratified with concentra- tions such that the mixture is relatively uniform along the inner wall surface of the cylinder. cylinder head but becomes progressively leaner as it moves away from the surface of the cylinder head. The stratification of the power supply is thus carried out efficiently and positively, which provides a remarkably good capacity for adaptation to the air drawn into the engine.

   As regards the region outside the scavenging air stream, such as for example the region adjacent to the cylinder, a good degree of scavenging is obtained in the vicinity + mediate of the internal wall surface of the head, while this degree decreases towards the center of the cylinder where an increased amount of residual gaseous constituents from the previous run remains. When stratification of the feed is carried out so as to form a rich mixture in the region of the stream. outside) the main vortex, the feed composition is stable and the air supply is well balanced with the air consumption.

  <Desc / Clms Page number 15>

 



   Likewise, it is possible according to the invention that the combustible mixture is spread stably over an extended region of the surface of the inner wall of the cylinder head and the mixture is then maintained for a relatively long period of time. in the space of the cavity, the possibility of modifying the spark angle with respect to the setting of the fuel injection then being made * sufficiently large to allow a relatively free selection of the setting over time of the spark - that regardless of the timing of the injection This tendency becomes more pronounced with the rise in temperature of the head.

   Fuel particles injected from the orifice of the injection nozzle are spread and evaporated as they approach the inner wall surface of the head, except for conditions at the very beginning and. as a whole, the swirl rate within the cylinder is suitably slowed down to allow stratification of the feed to easily achieve a desired intensity and richness.



   The air-fuel mixture containing injected fuel particles and the fuel evaporated from the inner wall surface of the cylinder spread well into all recesses of the combustion space and from the surface of the particles. and the densities of the particles as well as the mixtures per unit of volume do not reach very high values. Factors combine to exclude the possibility of a faulty ignition due to too high a concentration around the spark plug during the introduction of excess fuel.

   Even with operation at partial load and with low fuel injection, a sufficient air-fuel ratio is maintained in the ignition zone of the combustion in order to exclude an ignition fault, retarded combustion or other cloudiness with a fairly lean general mixture.

   The fact that good combustion is thus

  <Desc / Clms Page number 16>

 
 EMI16.1
 total load and in> 3 ==; ce; li == -'1U'C '.in cnc tirJ1e ", e.'l s1-; a partial light and oei e; c4à = nt .j' a: ¯ : .e: -, ::. tiC4 in air, offers practical advantages :: - .; :) r: ne3 oared ': rc ;!,. ::' :; cr des mcT: 1 ..:. rs The consumption 3ci =.:. cr by caxbarant in the part-load region where the cars are generally made to run is greatly improved and, in addition. a p-. ication of the exhaust ga .: obtained positively in order to solve the problem of dangers due to emissions polluting the air, easily and without resorting to complex and expensive additional accessories for this purpose.

   In addition, direct fuel injection offers powerful acceleration, good fuel distribution and the ability to adapt to efficiency under easy flow.



   According to the present invention, the fuel can be easily ignited either by the mass of fine atomized particles of the injected fuel, silk by the gas mixture consisting mainly of the vapor coming from the atomized fuel and the liquid film deposited on the wall surface. internal cylinder, or by mixing the two. The ignition flame strongly promotes further evaporation. After firing or ignition, the combustion gas which is light flows naturally to the center of the main swirl stream and is replaced by fresh air, which in turn participates in the process. mixture formation and subsequent combustion.

   With such a combustion mechanism, it is possible to realize the fuel injection with a pressure high enough so that the ignition and combustion
 EMI16.2
 are mainly initiated by the mass of fine particles atomized at the time of start-up and immediately after start-up when the cylinder temperature is low, and by decreasing the injection pressure when the cylinder temperature is increased

  <Desc / Clms Page number 17>

 to a suitable level, which consequently reduces the load imposed on the injection pump, while then allowing the mixture of vaporized fuel and air to resume the task of ignition and combustion. from the mass of fine particles which have been automated,

     to ensure satisfactory combustion and operation
In the combustion mechanism according to the present invention, the speed and the highest temperature of combustion can be controlled in part because the mixture contains a certain amount of residual gas (i.e. inactive gas) already. burned during the previous stroke and partly because the residual gas is distributed more densely in the central area than in the nesting part, therefore the rate of pressure increase can be kept at a lower value than in conventional four-stroke engines which burn homogeneous mixtures and the maximum pressure inside the cylinder can also be reduced to provide a lighter engine.

   It is further possible to minimize the noise produced and therefore to achieve a quieter operation of the engine. The arrangement contributes to a large extent in controlling the emission of NOx, which is a source of danger to the public. Since the fuel is supplied by direct injection into the cylinder and the residence time in this cylinder in the form of unburned mixture is reduced, the anti-knock property of the fuel is enhanced - moreover, since it does not there is no exhaust valve and other parts that can serve as a heat source, for example in the vicinity of the cylinder head and since the combustion chamber has a semi-spherical shape which is compact and close to an ideal configuration,

   the mechanical octane number of the carburart

  <Desc / Clms Page number 18>

 is increased and improved thermal efficiency is obtained due to an increase in the compression ratio. The moderate pressure increase rate and the relatively low maximum pressure allows the use of moving parts of reduced weight and quiet operation at high speed, thus making it possible to expect an increase in pressure. specific engine power.



   According to the invention, the combustion is obtained using particles and a spread mixture; over the entire region along the inner wall surface of the cylinder head and. therefore, the thermal load on the engine is heavy on the cylinder head and relatively light on the piston, the moving part. This is highly beneficial in cooling the piston and in lubricating the sliding surface of the piston relative to the surrounding wall of the cylinder.



  On the other hand, the stationary head which is subjected to a high thermal load can be cooled relatively easily from the outside and thus the temperature control is made easy. The ample time allowed for the ignition timing over time results in a stable and practically useful stratified fuel supply while allowing operation with a lean, total air-fuel ratio.

   With the qualities which preceded the engine can dispense with a choke or throttle with remarkable advantages as to the improved thermal efficiency and the reduction of the harmful contents in the exhaust emissions during the operation under a partial load.
Although the excess air used according to the invention reduces the combustion temperature, on the other hand it improves

  <Desc / Clms Page number 19>

 the specific thermal ratio of the active gas. -reduces- the loss -of - - heat by cooling to the outside and reduces thermal dissociation during combustion. This leads to an improvement in thermal efficiency and to a strong reduction in the percentage of carbon monoxide. CO in the exhaust from excess air.

   In addition, the presence of excess air, the absence of the possibility of uneconomical dispersion of the fuel particles and the stable stratification of the feed combine to prevent the extension of the area in which the mixture becomes. too poor to burn. this in turn reduces to an appreciable extent the emission of hydrocarbons, HC. in the exhaust due to incomplete combustion, keeps the combustion temperature low and keeps the combustion temperature and maximum pressure during combustion at moderate levels with an air-fuel ratio generally lean enough to fall into the ignition fault zone.

   Because of the self-circulating property of the exhaust which is peculiar to the inactive gas and also because the distribution factor in the exhaust flow pattern is high in the central region of the combustion chamber, the production of nitrogen oxides, NOx (especially in the high temperature zone in the center of the combustion chamber can be reduced suitably.

   It should be particularly noted that, in the engine according to the present invention, the combustion temperature in the central region of the combustion chamber is effectively kept low because of the relatively high percentage of residual gas which has already burned in the combustion chamber. during the previous stroke in the central region of the cylinder and therefore a general purification of the exhaust is made possible without a resulting reduction in engine power.

  <Desc / Clms Page number 20>

 
 EMI20.1
 



  '' - 5rI = 9 ---: 5 -.-: Cr -.- t; qu H is envisaged according to the invention q--: :::: -: r. : L ¯¯ 2.:. :.:, "l: .. dra. your sawyer does not SU¯:,?:" ".. 1" '? t e = ¯ ¯ ¯ ¯ ¯ ¯ ¯. : ¯. - "!: '31i: e: 1 :: at.i mais serve ga' :: 'ee: 1:':.:: R. Ce:?. ==: a #; 'r', ..: 1 cnxumasde ate temperature is made xtr: 7 ':: -. e .. :: 3. ",; - ..;.: - :. : - ,: 1;:,; e: '1'S an no way imposed on udder = c =, <.!. -j): 1.:.: .. r '. = no larger amount of the feed al: ¯¯3¯éQ and hralée along the surface of pa: ^. ¯: tez-: z l: 2 of c.W¯nd..rQ, an consequently reducing; '.' 1 charge.:.: E =; 1 <r '; e imposed on the piston.

   Thus, a combustion engine == ie = n-; 4th ¯¯ ... = .. general ¯or¯ of the two-stroke ee, in which? E .; . z .'-- - s,. "alternative ent have: no additional weight3i = ,: W 3:;: - ':;>'. 1 .-: - ¯ :::, :: light for m1n high speed operation53e cor.yr:; 2 -c, ar n3équent 1 3-improve the effective pressure: ave # ne c 1.?;. qp = enra = ion of the specific engine power, can be offered 3VC a simplified construction and at
 EMI20.2
 a low cost price.
 EMI20.3
 



  Since <3 the motor according to the invention depends uniquenent on the combustion in a main combustion chamber of simple design, it is free from the complexity of the engines with ali-entation stratified ordinairaséquipésd'une auxiliary chamber. 1. Can do without the current ccrcnunication passages which entail additional t: eriç ^ es losses and it offers a less large surface area of pa> i. The engine following the i: 1'.1 <1. :: :) :; :; e e, = = d,; 1 '; cu; lz = 1a 1 t d; ¯ ..... ¯.:. S = -¯on often proper {iX ';: -'-;' ::;: .- ::> 3 ': .--:' -.> '; - : .-. iu # .1 -.-... .. ¯ ¯¯ la: r.ê .. "er aison, 1: .-: - '. (-is the" ^' 3 '. ¯ :: ... :. 'C. ..¯¯: - 1-, il #. R:' - F such. -That they are 8 = 4jà <# 1-. -; 5r '; "- '2 1- 7 * 3 c :: js # defined by pis-' 7. f =: n; n- -;, a ;;. - :: '" 1 ", t.? 3 = - Jns4quelt, there does not exist ¯ ¯¯¯ ,, -: PJ ,.

   S: 1J¯:;, .¯: ¯: ti.; R: ne .iizr, i "'.. ::: é - :: nta1r at the 3tr" JCt: \:.-.-, SG1W' TI cs' 1 '' <'- ...:' 1CE'r: a '¯ weight, 302 =: 1 ce q' .. It conceals the thermal load, with the result that 1 '± fet du
 EMI20.4
 ;;;; t.7 :: r ,,:, \ ::? t ..: C ': .. t: .¯t., mm <aremenP.dra -Ta <- -> 9nt - <W + <qUa> iement

  <Desc / Clms Page number 21>

 Improved - The fuel injection is not directed towards the sliding face of the cylinder nor towards the piston.

     but it is temporary. It is retained in the cavity where it is not directly exposed to the air stream pr @@ c @ pal and thus the injected particles are atomized into tiny particles. Therefore, the atomized particles in a suitably layered state are carried away by the main stream under the combined action of the scavenging air stream or a swirling air stream based on the latter and even more. air current which is superimposed on it.



  In this way, the lamination is carried out stably. There is no possibility that the atomized particles will be projected directly against the sliding wall surface of the cylinder and thus the disturbances which are often encountered on the lubricated surface due to direct fuel injection into the cylinder such as. in conventional engines can be avoided. Also, it is possible to omit the choke for air intake with a stratified feed engine or, even if the choke is provided, the dependence on it can be remarkably reduced. . This feature can be fully exploited from a different perspective painting.

   For example, in an engine of the crankcase compression type, the suction and crankcase compression works can always be kept above certain values regardless of the operating conditions. If necessary, by cutting off the fuel injection during * decelexation
 EMI21.1
 a = in increase, t3nt the compression work in the crankcase by adjusting the air throttle, it is possible to obtain the effect of a
 EMI21.2
 motor brake, so SOr'¯2 that the disadvantage of insufficient motor braking for a conventional two-stroke motor can be easy-
 EMI21.3
 "" 6 ",;

   ".... ±; 1. N¯.a f: 3." '' '' - "" '¯.2 ""'. A.1 "-6

  <Desc / Clms Page number 22>

 
According to the present invention, a swirling air stream having the basis of the purging air in the cylinder of an ordinary two-stroke valveless engine:

     is used and the fuel is injected against cu following the direction of the vortex from a suitable position and at an appropriate angle relative to it and, Tracs to the action combined with the curant of swirling air, the -speed is spread along the inner surface of the cylinder head to achieve a stratification of the feed. In doing so, it is possible to use not only gasoline.

   but also lower quality fuels such as kerosene and light oil as well as gaseous fuels such as propane, depending on the combustion mechanism and the course of the mixing process - This system can be applied just as effectively to four-stroke engines which have the slow sweeping behavior of two-stroke engines It is not necessary to have an adjustment means to keep the mixture ratio of the air intake constant as is necessary in conventional engines ¯ The fuel alone can be adjusted independently of the air supply, while the air intake is kept open and the possibility of control is simplified.

   Since the fuel is injected directly into the cylinder instead of being supplied to the engine suction inlet as is usual, there is no possibility of reducing the efficiency of the engine suction volume and gaseous fuels can be used without reducing the power delivered compared to liquid fuels. Further, the period during which the fuel remains as an unburnt mixture in the cylinder is reduced and this coupled with the inherently high anti-scaling property of LPG gas. ensures improved thermal efficiency due to the increased ratio:

   compression and makes possible the expectation of an increase in the power supplied.

  <Desc / Clms Page number 23>

 



  Further, according to the present invention, the fine atomized particles of fuel: injected or a mixture in the form of a mist of the vapor thereof is ignited and. consequently, the engine which is not yet sufficiently: warmed up or which is still cold can be; nor started without difficulty. Therefore, the engine is suitable for cold starting and provides a good ignition and combustion process under any load condition.

   The mode of combustion is in most cases such that the flame propagation of the vaporized mixture is combined with the spreading and combustion of fine fuel particles and, therefore, the rate of pressure increase is relatively low. and a quiet internal combustion engine can be obtained with which minimum operating noise can be obtained.



   In the engine cylinder, stable stratified power is offered under optimum conditions and, therefore, there is no critical relationship between fuel injection and purging air stream, while wide facilities are available. offered for crankshaft angle across range from near piston bottom dead center to compression stroke. The same is true of the fuel injection with respect to the timing of the ignition.

   For example, while the fuel injection initiation angle is changed from 1400 before upper dead center to 80 before this same dead center, i.e. over a range of 60 depending on the crankshaft angle, the timing of the ignition can be changed independently of this and ignition as well as operation is made possible without any undesirable consequences over a range from about 40 forward of the upper dead center to a point beyond this dead paint, although this is accompanied by some flow in the ures- -
 EMI23.1
 ... Stt,

  ..flffi and the effective pressure tnoy '(this has co1fir-

  <Desc / Clms Page number 24>

   Fuel and ignition can be controlled independently of each other to a very large extent. There was no limit imposed by difficult-to-adjust critical ratios between the three requirements of air swirl, fuel injection and ignition, as seen with conventional tratified fuel engines. In this sense, the engine can be treated practically as an internal combustion engine of the electric ignition type and, moreover, it can be made to function rationally by changing the above factors in wide ranges.



   According to the present invention, operations with excess air, in particular with very lean air-fuel ratios, are possible without trouble. It is for this reason that it is not necessary to have an adjustment of the air restrictor in the partial load range or, if there is one, the dependence on this. adjustment is reduced.



  This also serves to improve thermal efficiency and reduces harmful levels in the exhaust during operation or at part load. In the wide load range from no load to medium load, the fuel consumption rate of the engine according to the invention is close to that of commonly used Liesel engines. Under full load conditions, the engine according to the invention can provide the tendency for ordinary fuel consumption of gasoline engines. Thus, a remarkable improvement in efficiency is possible for a gasoline engine using a spark ignition system.

   As an automobile engine, for example, the engine according to the invention can offer not only smooth running characteristics with the specific power inherent in the gasoline engine, but also the economy of

  <Desc / Clms Page number 25>

 Almost as satisfactory fuel and 1: 1 exhaust purification cannot be used with existing diesel engines, yet still lack the smoke characteristic of the latter.



   Further, the present invention provides an engine capable of achieving even more stabilized power stratification, by expanding the range of mutual tolerances of fuel injection and ignition, establishing operation and stable and favorable engine performance while still ensuring the achievement of clean exhaust emissions. Since the feed thus stratified is such that the mixture is richer and the density per unit volume of the mixture greater in the vicinity of the peripheral region, the balance between the fuel supply and the intake d air and naturally maintained in a favorable manner. The process of movements is stabilized and the flow of the mixture is relatively moderate in the vicinity of the spark plug.

   There is no possibility that the flame will go out. In addition, due to the generally ideal contour of the combustion chamber, the fluctuation of the combustion cycle is limitedēAll this leads to the net benefit of a positive materialization of efficiency improvement and reduction. hydrocarbons imbrQlés in the exhaust.



   Since the stratified feed is formed in the combustion chamber of the engine and the combustion process does not involve the instantaneous timing of fuel injection and ignition relative to the vortex of As in conventional stratified fuel engines, a very wide tolerance is offered as to the timing of fuel injection and ignition according to the present invention. Therefore, the timing for fuel injection and firing can be set freely and independently of each other to a very large extent.

   For example, it is possible to fix the timing of the fuel injection and modify the

  <Desc / Clms Page number 26>

 ignition advance angle only. This eliminates the control delicacy in ordinary stratified feed motors.



   For the practical implementation of the present invention. the wide tolerance between the fuel injection and the alloying and the formation of the air stream also offers a fairly high degree of flexibility with respect to inadequate injection conditions, such as, for example, during fouling of the fuel. injection nozzle for fuel supply. Thus, a minor deterioration of the injection conditions cannot have a appreciable detrimental effect on the efficiency and this is another factor which contributes to the better reliability of the engine.

   As a result, the timing for the priming of the fuel injection can be fully advanced and the effective crankshaft angle for the injection can be increased, thereby forming a mixture. suitable without any interruption in the main air flow for the turbulent flow in the cylinder.



  It is made possible to operate with the speed of use of the air inside the cylinder under full load conditions increased to the extreme limit and with the air-fuel ratio increased to the excess in the entire space of the combustion chamber, with a condition practically free of -4-ruined and without any disturbance. There is no possibility that operation will be limited by exhaust and smoke before the mixture inside the cylinder becomes completely excessively rich. Thus, the engine according to the invention is advantageous in practice in that it can operate with excessively rich ratios between air and fuel under conditions also of full load, in a satisfactory manner as the engines.

  <Desc / Clms Page number 27>

 classic.



   It should be obvious that effective means for purifying exhaust emissions, improving engine efficiency and for simplifying and extending the life of component parts can be incorporated, where it seems appropriate, in the construction.



   Further details and features of the invention will emerge from the following description, particularly applicable to a two-stroke engine of the valve and piston type, with the Schnuerle scavenging system, as an alternative. non-limiting example and, with reference to the drawings, in which:
Figure 1 is an elevational view in section of an internal combustion engine according to the present invention - -
Figures 2 and 3 are large-scale and partially sectional views of the engine of Figure 1-
FIGS. 4 and 5 are schematic views mainly illustrating the movement paths of the particles or of the fine droplets of the injected fuel.



   Figures 6 and 7 show trajectories of fuel droplets as developed along the inner wall surface of the cylinder head and as seen at the piston head.



   Figure 8 is a schematic view of the relationship between the cylinder head and the main air stream inside the cylinder.



   FIG. 9 is a schematic elevational view showing another form of current injected from an injection nozzle.



   Figure 10 is a schematic plan view taken along the line I-I of Figure 9.

  <Desc / Clms Page number 28>

 



   Figure 11 is a schematic plan view of another embodiment taken along line 1-1 of Figure 9.



   Fig. 12 is a side elevational view in section of a still another form of mechanism having essential elements for obtaining a layered feed.



   Figure 13 is a side elevational view mainly illustrating the travel paths of the injected fuel droplets in Figure 12.



   Figure 14 is a plan view illustrating the trajectories of the fuel particles in Figure 12.



   Figure 15 is a side elevational view in section including another form of fuel injection nozzle.



   FIG. 16 is a side elevational view showing mainly the travel paths of the injected fuel droplets,.



   Figure 17 is a plan view corresponding to Figure 16.



   Fig. 18 is a side elevational view in section of another form of cylinder head, including parts essential for forming the laminate filler.



   Figure 19 is a sectional view along line IIeII, of Figure 18.



   Figures 20 and 21 are schematic views illustrating the travel paths of the fuel droplets in Figure 18, Figure 20 being a side elevational view and Figure 21 a plan view.



   Figure 22 is a sectional view of yet another form of mechanism having essential parts to the formation of the laminate feed.

  <Desc / Clms Page number 29>

 



   Figure 23 is a sectional view along the line III-II of Figure 22.



   Figures 24 and 25 are schematic views illustrating the travel paths of the fuel droplets shown in Figure 22. Figure 24 being a side elevational view and Figure 25 a plan view.



   An essential feature of the present invention lies in the fact that the fuel injection can be carried out either against or along the direction of the main air flow in the engine cylinder without any disturbing effect, so that the stratified feed realized by the main air stream is available widely in time for ignition and that, in particular, the contour of the cylinder head, the construction and the location of the fuel injection nozzle and other factors combine under optimum conditions to allow the injected fuel droplets to be spread and evaporated, except at the very start of injection,

   as it approaches the inner wall surface of the cylinder head-
Another equally important feature is that a recess or cavity is provided in the cylinder head so that the spread droplets of fuel injected into the engine cylinder are not directly exposed to the main air stream in the cylinder. but are temporarily retained in the cavity so that they can be reubited into a mist forming mass consisting of a large amount of the fine particles and this mass can be subsequently entrained by the main air stream as a fuel mixture .



   Referring to Figures 1 to 8, a reciprocating piston 1 is connected to a piston rod 13 in a

  <Desc / Clms Page number 30>

 housing 12 and it is housed in a cylinder 4 which is formed with an exhaust port 2 and a scanning port 3, both intended to be opened and closed by the movement of the piston 1.



  The head of cylinder 4 has a semi-spherical inner wall and is formed with a cavity 6 of smaller radius and is deeper than the semi-spherical contour. Through the internal wall surface of this cavity 6 is provided an injection nozzle 7 intended to supply fuel to cylinder 4.

   Fine fuel droplets supplied from the injection nozzle 7 are directed to flow along the surface of the inner wall of the inner wall of the cavity 6, so that the fuel flow can be introduced against cu in the direction of a swirling stream of fresh air S of a: r supplied to cylinder 4 and the resulting action can laminate the combustible mixture along the surface of the wall cylinder 4.



  The cavity formed in the cylinder head 5 is shaped like a semi-sphere, sector or other configuration effective for layering the feed. The surface of the wall in the direction of injection of the injection nozzle 7 provided in this part is shaped so that a front edge part 8 which constitutes a delimitation between the head 5 and the cavity 6 is connected to an inclined wall portion 9 and the opposite end of the wall portion 9 is uniformly curved and extended by a planar or curved top portion 10. As viewed from the top, the front marginal portion 8 is formed as a circle: concentric with cylinder 4.

   The cavity 6 is also equipped with a spark plug 11 near the center and the injection nozzle 7 along the spark plug was in a suitable position and at an appropriate angle relative to it.

  <Desc / Clms Page number 31>

 



   The injection nozzle 7 is provided with a nozzle orifice
7 'on one side of the end which is intended to inject fuel towards a swirling air stream S which is based on the sweeping of the cylinder 4, at a certain angle of spray divergence.



  Although the zone of directed injection is located beyond the spark plug II in the upper part 10 of the cavity 6, it still lies along the inner wall surface in the vicinity of the spark plug (Figure 2 ). This inner wall surface has a suitable shape so that a suitable localized air stream can be produced in the cavity 6.



   On the contrary, in FIG. 3, the injection nozzle 7 is located upstream of the spark plug 11 with respect to the swirling current S and the flow of fuel injected by the injection nozzle: 7 is directed downstream, so as to flow on the sweep current. The location of the nozzle is such that, in the absence of the air current, the injected fuel would reach a region close to the region upstream of the spark plug 11 (i.e. - say the region / lying not beyond this candle 11). In any case, the elements are arranged so that the injected fuel can be finely atomized and sprayed at a certain angle of divergence from the swirling stream S based on the sweep stream.



   In Figures 9 to 11, the injection nozzle 7 is shown as provided substantially in the center of the upper part 10 and is provided with several nozzle orifices 7. for the areas to which the fuel is. directed. In the embodiment shown in Figure 9, for example, a nozzle 7 is used to inject fuels in radial streams, which represented a combination of streams having either normal or opposite force components to DOBIGINAL swirling s.

   Even the streams of injected fuel

  <Desc / Clms Page number 32>

 
 EMI32.1
 which extends "laterally or perpendicularly to the air stream as shown in Fig. 11 has a certain angle of divergence and can also be divided into two groups, one having opposite force components and the other inverse components.The axis line of the jet streams is considered to be an end where the entity or the component of opposite or reverse force is reduced to zero. Therefore, it can be incorporated into a current either opposite or reverse When incorporating splash flows, these streams can be set up to create even more favorable flow conditions and atmosphere for combustion.



   Although not shown, the injection nozzle 7 preferably has three or more nozzle ports 7 'in order to produce by itself a relatively uniformly dispersed mass of fuel droplets in the frontal region. When two of these nozzle orifices are provided, they obviously cannot by themselves provide a uniform mass in the opposite region, but the front wall surface of the cavity 6 in the shape desired to stop and disperse the mass of the droplets. injected fuel and consequently form a flow of droplets in which any rarefied inhomogeneous part is compensated by these dispersed droplets. In this way, a relatively uniform mass of fuel droplets is obtained throughout the region in front of cavity 6.

   In the region of direct injection in the direction of injection, each fuel stream is not extended excessively laterally along the adjacent internal parai surface, but instead moves in the form of a ribbon. Thus, it is taken into account that the streams can be dispersed with sufficient spread of a relatively homogeneous mixture along the cylinder head portion 5 and carried by the swirling stream.

  <Desc / Clms Page number 33>

 S, in order to achieve a stable stratification of the diet.



   For the purposes of the invention, the cavity 6 is intended to serve as a recess in which the atomized fuel particles introduced therein are not directly exposed to the main stream of swirling air S produced in the cylinder 4, but are at on the contrary, temporarily retained and mixed: in such a way that a large quantity of the fine droplets can coexist. Likewise, the cylinder head 5 constitutes the part which surrounds the interior of the cylinder from the vicinity of the upper dead center of the piston 1 or, in other words, the wall part of the cylinder head other than the part along which the piston 1 slides inside the cylinder 4.



   As piston 1 in cylinder 4 descends from an upper position adjacent to cylinder head 5, exhaust port 2 is opened first, allowing part of the exhaust to escape. and then the scanning lumen 3 is opened, when the fresh air compressed in the housing 12 is injected through the scanning lumen 3 as a stream of scavenging air S1 as indicated by a dotted curve with an arrow. In this way, the residual waste gases in the cylinder 4 are swept away and fresh air is supplied to it.

   When the piston 1 is near the lower dead center, as shown in figure 1, the exhaust port 2 and the engine scan light 3 are both open and the scan is performed with air. cool, while a strong scavenging air stream SI is created from inside the cylinder. Subsequent raising of piston 1 first closes scanning port 3 and then exhaust port.

  <Desc / Clms Page number 34>

   2.but the air encoder in the cylinder remains since it is replaced by the swirling air stream S, as shown in figure 2, due to the law of conservation of motion or by its force of inertia and it is gradually damped.



  The swirling air stream S has a normal vector of rotation with respect to the axis of the cylinder and the composition distribution of the air and the exhaust gases already burnt from the previous stroke in this zone of the vortex is such that the proportion of exhaust gases is high in the central zone and the proportion of fresh air is high in the peripheral zone.



   In such a flow zone, pressurized fuel is injected from the ejection nozzle 7, in the form of finely atomized droplets and at a suitable time.



   The injection is directed towards the interior of the cavity 6 of the head
5 and towards the wall part 9 a recess provided so that the air exerts only a slight influence. Thus, any anti-economical dispersion of the fuel droplets injected at high speed into the non-combustible region is excluded and the dispersion and mixing of the tiny particles in the recess is promoted to an optimum state. In other words, the mass of the injected fuel droplets is thus formed into a stream of deflected and dispersed fuel droplets and a relatively homogeneous mass of fuel droplets or a mass containing a mixture of air and fuel is obtained. Vaporized fuel is produced, throughout the region in front of cavity 6.



   The actions described above are reinforced by the combined action of the air currents S and SI and consequently the operations of dispersion, scattering, mixing and transport are carried out in succession for the stratification of the feed. To be more precise, the flow of the air currents S and Si gives the same effect as that obtained by a generator of turbulence in the frontal marginal part 8 of the

  <Desc / Clms Page number 35>

 cavity 6. Local turbulence produced in this region causing mixing, dispersal and rarefaction? suitable air with the mass of fuel particles containing the vapor thereof.

   The resulting mixture is richer towards the peripheral outer region and leaner towards the inner central region of the vortex. Since the flow zone is formed by a vortex, a centrifugal force acts and, since in this flow zone the proportion of fresh air is increased and the mixture becomes richer and therefore the bulk density is higher towards the outer region, the flow conditions are extremely stable.

   Thus, the overall stability of the flow maintained despite the localized mixing effect, for example through turbulence, means that the extension of the portion of the layer which is made too lean to burn is avoided or minimized, if there is one-
As described, while the obtained general air-fuel ratio is high from the standpoint of the combustion chamber as a whole, it is possible to prevent unnecessary scattering of the injected fuel droplets and to prevent the expansion of the fuel droplets. the layer made too lean to burn, consequently keeping the emission of unburnt hydrocarbons in the exhaust to a minimum. Part of the mass of injected fuel droplets strikes the surface of the wall and is deposited there.

   However, this is a secondary phenomenon. Most of the fine droplets are rapidly evaporated, because the fine droplets are very widely scattered, the wall temperature is kept at a moderate value, and the temperature of the air itself increases with the progression of compression. If the mass of the fuel droplets is caused to partially subsist

  <Desc / Clms Page number 36>

 until the final stage of compression, its evaporation is favored by the heat of ignition and combustion and it is gradually incorporated into the stratified charge in order to take part in the combustion, thus contributing to combustion full of fuel.



   We will now examine the case of a typical droplet of fuel injected through the nozzle orifice 7 'of the injection nozzle 7 shown in FIG. 4. At a pint P immediately after injection. , the vector of the displacement velocity @pr is significantly greater than the vector of the air velocity pp @ and therefore the influence on the displacement path of the droplet is limited and the deviation from the line CO which is the primitive course in the absence of a vortex. is negligible. In fact, however, the droplet is so tiny that it can be braked very easily, and by the time it has reached point R its velocity vector @@ has already fallen to a very low level.

   On another side-. the value of the vector of the speed of the swirling air RR changes little and is considered almost equal to PP 'and. therefore, the influence on the displacement path of the particle is large, and the deflection value is also increased. Therefore, the curved path OO is followed.



   Even if the fuel droplets are injected in the same direction with the same speed, their trajectories vary with dimension. As shown in Figure 5, for example, a large droplet is projected along the line CO1 of relatively low curvature. The smaller the dimension of the particles and the greater the curvature, as illustrated by way of example by the curves OO2 and OO3 Even small droplets tend to circulate on the vortex S and to be entered for example following the

  <Desc / Clms Page number 37>

 curves OO4 and OO5 before reaching the surface of the wall.

   The mass of the fuel droplets injected from the nozzle 7 adopts a certain distribution probability curve although the fuel is finely atomized and, therefore, part of the fuel consisting of relatively coarse droplets is dispersed over a surface. extended area of the surface of the wall and is deposited there, while the remainder which constitutes the majority of the fuel approaches the internal deposition surface of the head 5 but changes direction and accompanies the vortex S.

   -
In the above, it is possible to modify the trajectories of the fuel droplets by suitably adjusting the position and height of the nozzle 7 and the contour of the internal wall surface of the head 5 and also to modify the distribution. trajectories as well as the concentration and distribution in the mixtures of the vapor obtained from the wall surface.



   Generally, as illustrated in Fig. 6, fuel in the form of droplets is injected through the nozzle 7 'with a divergence of a certain spray angle a, but it is subjected to the action of the opposite vortex S. Considering two typical droplets M and N, they are considered to have the velocity vectors MM 'and @@ On the other hand, the vectors of the air current velocities are shown by the vortex vectors S, i.e. MM and NN Therefore, the two droplets tend to deviate from each other, i.e. the tendency appears towards a plus wide spray angle a.

   As already e: plique, this depends on the size of the droplet regardless of the injection speed.



  Therefore, as illustrated in Figure 7, the trend is favored by the associated local air currents due to fuel injection.

  <Desc / Clms Page number 38>

 fuel and, in total, the fuel droplets which would be injected directly into zone E if it were not for the opposing air stream F, are dispersed opposite the counter air stream in the extended region up to zone S. The fuel droplets, approaching the wall are moved in the direction of the swirling current S.

   In addition, since the temperature of the air increases with the progress of compression, and because the fuel droplets are maintained at a relatively high speed compared to the flow speed of the air vortex. , as already described, the evaporation from the surface of the fuel droplets is accelerated.



   If the head temperature is kept high enough, the fuel dispersed and deposited over the large area is quickly evaporated and mixed in the turbulent swirling air stream. It thus contributes to the formation of the swirling current together with the fine droplets which do not settle on the wall surface of the cylinder and evaporate by themselves, in order thus to arrive at the stratified feed. After the fuel injection and the large scattering, the great dispersion and the mixing of the sufficient quantity of fuel and after a good progress of the evaporation, the mixture is ignited and ignited by the spark plug 11 located in or downstream of the fuel loaded region.

   In the vicinity of the spark plug 11, the atomized stream contains a larger quantity of fuel droplets and has such a high droplet density that ignition is possible even if the mixture has only a limited vapor content.



     Thus, with the exception of the very first stage of fuel injection, this fuel is spread as it travels towards the inner wall surface of cylinder head 5,

  <Desc / Clms Page number 39>

 regardless of the mixing action due to the turbulence and it moves further through the swirling air stream.

   This is combined with the presence of fuel droplets in the area of the centrifugal force having the vortex as its base, in order to allow the fuel droplets having a density greater than that of air to approach the surface of the head. 5 and, at the same time, incorporating these droplets into the vaporized fuel mixture of higher density than air, so that a stable state of stratification of the feed can be obtained.



   The intensity of this lamination can be varied by changing the location of the nozzle 7, the contour of the inner wall surface of the head, etc. It has been shown by experience that when the configuration of the cylinder head 5 is as shown in Figures 1 to 5 in Figure 8. The front marginal part 8 forms an angle with respect to the vortex and the delimiting layer downstream is thick or a localized counter-flow region G is produced or turbulence formed from this region, the mixture containing the atomized fuel droplets is spread over or beyond the angular portion throughout the region of the head 5, thereby allowing a desirable combustion process.

   Therefore, when fuel is injected against the direction of the swirling air stream in the cylinder, the combustion flame propagates through the entire region inside the head 5. This means that the heat load is. important for the internal surface of the head but reduced for the surface of the piston 1 and this brings many advantages from the point of view of cooling and lubrication. The effect is further beneficial for the purification of exhaust emissions.

  <Desc / Clms Page number 40>

 although hydrocarbons, HC, and carbon monoxide, CO which are
 EMI40.1
 remained unburned during the combustion stroke and the escape remains on the inner wall surface of the teat,

     the incident purging air acts to acon -le the air injected into the exhaust valve chamber of a conventional four-stroke engine. This amounts to saying that the reaction of imbr @s residues is favored by the supply of fresh air and this not only helps to produce a clean exhaust, but imposes a significant combustion load on the internal wall surface of the head, which is very effective and useful to promote the actions described above
When from another c3zé, the fuel stream injected from the nozzle 7 flows in the direction of the swirl S and merges with it as shown in Fig. 3, the relatively coarse fuel droplets are little. affected by the draft,

   ! due to the injection angle and they are scattered and deposited on the inner wall surface up to the spark plug 11 and are finally evaporated as the relatively fine droplets approach the inner wall surface of head 5 5 but, before contact with it, they accompany the movement of the swirling air stream S
 EMI40.2
 and, hence: t: 5th note that in the case of the air stream in nppcsiticn, the mixture connenan, the fuel particles and stratified.



  In this case, t:) \ :: - '! F, :) i3. the vortex is made more i-tsnse by the air current accompanying the = "c2iD: 7 3 carburT-. 3 '= c for result fir' :. 1 -. '., 3, -y ^ .E containing las gac = # ele = ts'. ^. i :: -. :: ra..ït is er.sin of> 3rala = 7 .'Cr'.vr¯2r'c'¯ ^ ... and = 1 from # 20ec # <1. the shape of a ribbon.



   In the above, the injection of fuel from the nozzle has been described, by way of illustration, as then being carried out after the completion of the balzyage and / the intake ports.

  <Desc / Clms Page number 41>

 and -air exhaust have been closed and the air flow inside the cylinder there has become a swirling current.



   In fact, however, the fuel can be injected into the air stream which takes the form of a sweeping air stream or a swirling air stream based on the flowing air stream. say that the exhaust port or both the exhaust port and the intake port are kept open, unless atomized fuel particles or the resulting mixture escapes through the exhaust port . This is quite advantageous under increased loads, because the dispersion, mixing and evaporation of the fuel is completely achieved.



   In FIGS. 12 to 14 there is shown an embodiment in which the atomized droplets coming from the orifice 7 'of the fuel injection nozzle 7 are not directed along the upper part of the cavity. 6, but they are supplied to the latter in particular in the immediate vicinity of the vortex S inside the cylinder - At the point P which is relatively close to the orifice 7 'of the nozzle, the existing velocity of each droplet is high and the resistance vector to which the droplet is subjected as it is projected towards = obverse of the still air is = and the resistance vector when the droplet remains stationary and only the vortex S exists is PQ,

   while the direction is identical to the direction of the tourbillon in this sentence. If the vector PQ is divided into the two force components, - '' - one in the direction of pp and the other in the direction which is perpendicular to it, we then obtain PQ 'and PQ ". Since the existing speed of the droplet at point P is much greater than the speed of swirling air, P 'P is much greater than PO Therefore, the vector P' Q 'is the resistance force to which the droplet is subjected against the direction projection, but given that it is: much greater than PQ "which represents the force causing the

  <Desc / Clms Page number 42>

 
 EMI42.1
 trajectory in the direction perpendicular to P 'ç' the çourtilerte = deviated from the + a j = cr = 1: e pri: n.: o. ':':

  'V2 .wain cēte 3n Z' Anz * n :. this of the tourbiü :. ¯¯¯ but.? ::: d3r¯ ¯-. -j: xnioia 1. ,, -. '. 7: '2.3: C:;,': "7. ' : 'lt..¯ ..:. ¯:.:' d "2-'UV - ': -., is originally l -?'. cfe,.:.: t1i: l" ue =. ii = api '.: e; e: - ;: .3.': è "; '3 d- = -.1 -: -; ..:.: -... lowercase mass, # 1 = te, e: ie elie-xème. fo e;: 'o,?. 2, - = r = ce of resistance at 3C. ±. The droplet es = submitted in the projection J; rs with the speed "'xi plants"' -'l poinc R is also W ':. the than RR'. On the other hand c ¯S the speed of the vortex S does not undergo = ... ¯. No appreciable variation and the resistance vector thus ar =, where = is RR?. Being asleep J the trajectory d2 the droplet is curved enough up to pcin ': R. R'R and RR- e; this point are approximately perpendicular to each other. Thus, the deviation of i the particle is cor.a = tè = able and the radius e curvature of the - 2 =
 EMI42.2
 roof is small.

   With -, a new progression, the vector of p7D-
 EMI42.3
 çression and the iec-¯eur 1e are directed 5 = li:; i "': -: - o2 way. It follows that çz ia is sour-4-se to U2 é = 7? drag and that the = 3': '0: 1 de = owrü'.: Ra de sa :: = oJ ectcire is r¯. ^. T: greater, from szrte 'J: l ..- = 1a.] Where \ .tte :;': :::. e eu1: 3rd è.5p- "ac2 = on the i.OLIDiiCi :. ¯. U- ... "1t C. ^ ¯ 33.t 1. i:;: ¯'¯¯: a? Īs'J secJ; = ca> == and localized,:.:. = -. C . ::. Jr ':? Ag: le :: 1 ECiC1' ::!. J ": 2-7) 1..I '" 1t SOB: .3 form of a trap of': ":: êS go'j celet. '": e: .. â': 'J-.i.:;és. serves 2? 1.: in j proT: lc ...: vr) ir - :. a.:i : 7 '\ e: 1-: .- = - s g01; :::: 2 = - = -. ::: es ..: e (,; 3I:.:.: R ": -J: - : ': 3.

   OZ'OdUCIC¯ '. : 4 @ a ':: ....: -.:': "'::;' ë -W 1" Js ....:. > q = 1 = from 41¯ - azni- .1 la "..--: E..3: 2" '¯: ..:. r ..:. i. ;; nE:.:': : i.:. ". :: - .." 1: ..- :. i- ": 04E'I'.lGr. '? C.,:":': - "'-: = -:' -: '' '' - 4 '' 1 1: -: = 1 .i; ¯ .ge = é # i; 1 = .E ;, '?;.: "7t') :: ':': ' : -: -. = -. at the time when 1 'was in.- es.: ... ¯ .-' ¯? 2¯., 2 a = t = e,; 1, Da-is ce zas, Les fines ÇOi: W lc ' t S injected a = 2x'¯? v of the nozzle 7 scrr- 3C1 :: PlSeß..3: .me TTi2sse well .if = é = e! 1 '::. e. = e that of the current of' .3. ": ':!:". iue ¯e 3roll.;. ent zroc7ressil ce La cc- = se de compr ± ssion. ia empéraure of: 'air esz a-ig-.7.entëe ē:

  'at-

  <Desc / Clms Page number 43>

 combined tion causes rapid evaporation of the droplets..and. preparing to mix fuel with air, exactly the same way as described above. This mixture forms
 EMI43.1
 -n density pattern #ei .-- e 1 density is relatively mini- forms along the surface of the inner wall of the cylinder head and becomes more narrow moving away from the surface of the head
 EMI43.2
 of ± * ylihÉre, 1o s% * i -¯..¯ïcr¯ that the mixed feed is thus efficiently obtained.



   The spark plug 11 is in a good ignition position, because it is located downstream of the injection axis line, even when the engine is at idle with very lean fuel supply injected. In addition, such a combination is largely insensitive to the relationship between ignition and combustion and the timing of ignition.



  In other words, a large tolerance is offered for a fairly free selection of one anqle advance for ignition with respect to a predetermined time setting of the injection and independently thereof. Furthermore, by providing the front marginal part 8 which serves as an angular part for the current
 EMI43.3
 ± 'ai scanning Si, the: é-a .-. Çz containing the atomized droplets is spread over the entire region downstream of the angular part or, beyond this, in the space of the cavity 6 of the
 EMI43.4
 t: Ste- 5, n-.è'ra when the cr'jc \ e 3e delimitation downstream is thick ::: rsç: .l '.1; -2 = é, ¯cr de ¯¯.¯¯¯ e - ¯¯ .. iE: 7t partial G oi a turbu- -e7 # ù e; -. : - 5.l ta !:

   c: xist- es - c, r¯it a very good process of conbustisn
Figures 15-17 show a useful embodiment in which a gaseous fuel, such as propane, is used for direct injection into the engine. In this embodiment, the tip of a fuel injection valve 17 is curved, extended and provided with a flattened nozzle tube 16 and

  <Desc / Clms Page number 44>

 extended laterally at the front end, so that a gaseous fuel can be injected into the space 6 in the cylinder head 5 with a certain angle of divergence to effect the mixing of the towed stream V against the line. direction and with vortex 5 that the sweeping air in cylinder 4 is based on.

   The @fuel injection valve. ' is of the solenoid type for supplying gas under controlled pressure and allows injection of gaseous fuel into the combustion chamber while the valve is held open. with an opening controlled on a crankshaft angle which is determined after the closing of the exhaust light 2, according to the speed of rotation of the engine and the position of the operating lever (not shown). The nozzle tube 16 is shaped with an outlet port 15 through which the gaseous fuel is injected at high speed and with a certain angle of divergence.

   In the part of the stream adjacent to the outlet 15, the proportion of air in the mixture is so low and the injection speed so high that the stream is subject to little influence from the vortex. lon S in the cylinder and the passage is unlikely to be curved. As the injected gas progresses, it is more and more mixed with the scorching air and it takes on a greater width with a progressive reduction in speed Thanks to the contours of the cylinder head 5 and the cavity 6, the speed of the gas is greatly reduced as it approaches the inner wall surface.

   Further, under the powerful influence of the vortex S in cylinder 4, the gas stream is pushed downwards as shown in figure 16) and it is spread along the inner wall surface: as shown in figure 16). figure 17). and while it is mixed with the air stream

  <Desc / Clms Page number 45>

 swirling, it generally circulates as if it were carried by the vortex.

   Particularly due to the fact that the front marginal part 8 which protrudes somewhat against the vortex S is provided on the head part 5, a thick boundary layer or a counter-flow region is formed downstream or although turbulence due to separation from the stream is produced, with the result that the mixture is made relatively homogeneous and is well spread across the gap in the cavity 6 of the cylinder head.



   Fuel injection serves to spread the mixture and at the same time accelerate the turbulence and brake the vortex. A strong component of turbulence which the vortex itself contains is useful for mixing fuel and is desirable for increasing the rate of combustion. Approximately when the spreading of the mixture is complete, the average circulation speed of the vortex tends to decrease as a whole.



   When the timing of the injection is advanced and this injection is carried out for an extended period as described previously. the gaseous fuel already injected is mixed with the swirling air and the mixture is forced in succession from the inside of the head towards the upper part of the piston 1 in the cylinder 4, until this cylinder is filled with The mixture.



   On the other hand, if the time of injection is delayed and the injection is limited to a short period of time, the result is a stratified feed inside the head.



  When the mixture is ignited with the help of a spark coming from the spark plug 11, with an adjustment in the appropriate time after injection, the combustion is amoxcee While the fuel

  <Desc / Clms Page number 46>

 
 EMI46.1
 ;? lzex: n: ecé ::: ar -: - :: - =. 3. - -:: '- ::': '"". T :: .¯j -2 .àGe - - "" -:; =: from a:' :: 2 i ::.: --- '::: 4: -'- ::: s ::.;: -:;: -:.-......-.:; ..:;., J: - ::'.} r -. :: ":.: t3.JC the --i:;:. =: .-: = e.; = e. ¯ ¯.w¯ -7 -. '::: ..-'. -: = - 51 ..: 5 in line .1- "1 ie ¯ -: - 7: .. J:";. '= - .:: ¯ .:.: "2 = e; - = -. (: ', c1 "' .. $ = ¯ C1C: de la 1; y, e i'- -.......: ':' l.:.r '': ': '4:' ":: '. T'l ... j'-4e;. =.) G-.css:' - I" s. \ 2:!: At by CO! 1Séq-è :: : 2 ¯'3. ¯ ¯: - .: 1.:..)Ir;;-- :: ..; e-t2L. ¯ ":". 3? 2. ':' .. ,, ' You.

   This 2ST. that if the ratio ds, '.: ei.' .. g less than 3v of cfi11: 2 according to 1.;!, = <-: -. 5 of I52 at ie richness ^ 2 ¯; ie'1 which is very desirable for sCls to fire and TOC.7uSW. It, that it becomes possible to use the powerful energy of the combustion flame produced by ignition for the easy reaction of the
 EMI46.2
 relatively poor lange entounnt. Ine ocnne '; OJ7'.!: US :: O: 1 is thus obtained with a general a.r-carbura ... ^ ¯ ratio very high.



  Since the s-.istem ^ t''W '4 # e 3Gy.¯Ctl a ^ O v2.1 which has no throttle. the amount of air supply required is little different under parrielle loads Ceei combines with
 EMI46.3
 poverty of c3 = 'urar, injected qT-j. ? r2Q has z- the cc'nbujiion in order to keep the temperature of the nozzle tube? 5 at a low level.



  Therefore, in these - = ';) ndit'; 'o: 1s, :: "' au-J7.1: 1ta ': icn ce -e-rperature of the gaseous fuel at c. = # Xrs of the injection is limited and in part, DU because LPG gas, / a similar gas originally has a greater
 EMI46.4
 density than air: at mother temperature, the resulting centrifugal force of the vortex tends to facilitate the sLat.i: .¯¯3- tion of the feed. This makes it possible to use even leaner air-fuel ratios.
The intensity of the lamination can be controlled by modifying the configurations, locations, directions of the nozzle tube 16 and its opening or outlet 13 as well as the internal contour of the head 5.

   The gaseous fuel injected from

  <Desc / Clms Page number 47>

 
 EMI47.1
 the sort is ccr.:e^a.,=ee^¯ T1éènçé, é ': random and stratified. I more, 7- = rt given that Ze caï tu-a ¯.: - a:;:.: C, s:; nz.c¯é ::. I: = ec1: e!: Slow in ''. 2 cylinder le = e ^ .ae ^ = .. ¯ -, z-: 7, e: ièmis5 11 -7ote -,; - r is not sacrificed as in 5 '.' '¯ -.'. ^ 2 classic view supply of the car- -During in the lur-tiere of a ': 7: ll.ss :: ..: Jn fui. engine. For these reasons, i? z'is not due? ossihili ': ë deze reduction of the power supplied retort in the case of an engine operating with liquid fuel.

   In addition, the residence time of the fuel in the form of unburned mixture in the cylinder is shortened and the anti-drug benefit.
 EMI47.2
 This is coupled with the mechanical octane number added due to the nature of the fuel and also with the increased compression ratio in order to achieve improvements in thermal efficiency and power output.



   In FIGS. 18 to 21. another useful contour has been shown of the cavity 6, formed in the cylinder head 5 in the embodiment described previously. In this case, the cavity 6 has practically a ton of. 'a sector contour and the opposite wall surface in the direction of injection of an injection nozzle
7 provided in the cavity st constituted by a frontal marginal part 8 which serves as a delimitation between the head 5 and the cavity 6, and a wall part 9 adjacent and perpendicular thereto, the vertical wall part 9 being extended to the 'other end by a curved part 13 to a flat or curved upper part 10.

   The cavity 6 thus offered has a wall / internal surface of such shape that the cavity is shallow in the vicinity of the front marginal part 8 and becomes progressively more <deep towards the injection nozzle 7. In addition, the inner wall surface in the cylinder head 5 is preferably curved to a semi-spherical counter generally matching that of the upper part of the piston.

  <Desc / Clms Page number 48>

 



   As shown in Figure 18 an injection valve 17 having an injection nozzle 7 directed to inject the fuel either at an angle or parallel to the upper part of the inclined plane of the inner wall surface of the head 5 is provided in the vicinity of the deep part 14 of the cavity 6 The injection nozzle 7 is made with one or more orifices and it is intended to inject the fuel at a certain angle of divergence in order to disperse fuel particles as seen in Figure 19. Even with a single port nozzle and simple design. fuel dispersal is obviously achieved satisfactorily by the combined action with the opposing air stream and with the aid of the head configuration.



   In the embodiment shown, two spark plugs 11 are fitted in the cavity 6 of the cylinder head 5. One is provided downstream of the nozzle 7, as observed following the direction of the flow of the current d. air sweep, and the other is conveniently located on the inclined plane surface of cavity 6.



  The internal contour of the cavity 6 is such that, as shown in Figures 18 and 19, it consists of a portion of inclined and planar upper wall sec-tor 10 and a diagonally cut portion 19, together defining a space in which the mass of the injected fuel spray is spread by the sweeping air stream or a swirling stream thereof. and one. relatively quiet recess and the part of the wall surrounding it. wherein the fuel is not subjected to the influence of the high air speed of the main sweep stream or the main swirl stream thereof. The front marginal portion 8 is preferably an arcuate shape concentric with the cylinder

  <Desc / Clms Page number 49>

 4.As best shown in the plan views of Figures 19 and 21.

   Likewise, the wall part 9 can be formed with an inclined plane instead of a vertical plane. In any case, the mass of the injected particles is deflected and dispersed to form a stream of particles which will fill the region in front of cavity 6 thereby forming a relatively homogeneous mass of fuel particles across the front region or back of the cavity 6. In addition, the particles are temporarily retained in order to provide a high density of particles, so that a stable stratification of the feed can be achieved. The path of each fuel particle injected from nozzle 7 into the cylinder head is as shown by the dotted line in Figure 20.



   Although it has a certain wide angle, the speed of the particles is such that the resistance vector to which the particle is subjected as it travels through still air is P'P-
If the particle is still at point P and there is a vortex S, the resistance vector thus produced is @@ @ the direction is similar to that of the air current at this point.



   If the vector PQ is divided into two force components, one following the direction of P'P and the other in the direction which is perpendicular to it, we then obtain PO and PO, respectively ¯ Because of the fact that the speed particle at point P generally much higher than the speed of the air stream, P'P is greater than po Therefore, the vector P'O is almost equal to the force of the resistance to which the particle is subjected to the opposite of the direction of travel and it is clearly greater than the vector PQ "which deviates the trajectory which is normal to it, as in the case already described. For example, the speed existing at the arrival at the point R is- very low and the

  <Desc / Clms Page number 50>

 vector R'R to which the particle is subjected in its circulating sns is small.

   In the meantime, the speed of the air stream 3 undergoes practically no change and. therefore, the advancing particle is fairly exposed to the main air stream and is strongly influenced by it. As a result, the particle follows a path, as it progresses, such that it is more and more strongly deflected by the air stream S, and the radius of curvature is decreased until the particle is carried over. the draft.

   This is to say, as illustrated in Fig. 20, that the fuel particles perform a compound motion with a tendency to broadly spread along the upper portion 10 as it approaches this upper portion of the inclined plane and they are entrained on the air stream S with the loss of most of the kinetic energy in the direction in which they were injected from the nozzle 7.

   Since this air current swirls in the vicinity of the head 5 and the particles are in the region of centrifugal force, a force is exerted to attract the particles towards the inner wall surface of the head, but they are largely spread along the inner wall surface of this head 5, while being suitably mixed by the air stream which in itself has a fairly vigorous turbulence. In this way, the stratification of the feed is achieved, forming a mixture which is richer towards the surface of the inner wall of the head 5. Although this depends on the direction of injection from the nozzle 7, only a small part of the atomized particles is spread, dispersed and deposited on the inclined flat surface 10 and other parts.

   These particles are also evaporated by heating by heat from the wall surface and the combustion flame and therefore form a mixture. However, this is only a part

  <Desc / Clms Page number 51>

 
 EMI51.1
 u - a seconaaxre pnenomene for The rortation to the mixture comsustloem 9¯ ": ¯" ,,:, "", ...- ,,; -:

   1 <> .- = -:. => -; <. =. i.-¯ = 'àJ¯; -, 1..j, - ..-....- we. =.;. ç ', ¯¯-¯ ;;, ¯,' # 1
Most of the fuel in the form of fine particles of injected fuel from nozzle 7 is exposed to the relatively high velocity of the air stream and, with the gradual progress of the compression stroke, the temperature of the air. also increases and the mixture is stratified with accelerated evaporation, until finally an atomized fuel mixture or a cloud containing the evaporated fuel is caused to circulate as part or all of the swirling air stream S.



   Since the internal contour of the head 5 is caused to converge, as shown in figure 19, towards the spark plug 11 and because of the action of the centrifugal field of the vortex, the mixture is collected in the vicinity of the spark plug 11 as a relatively rich cloud. In the hollow of the recess 6 where the spark plug 11 is located, conditions of relatively slow air flow are maintained. Since a pocket-like obviously which provides protection against the rapid air flow, this is desirable for the growth of the flame caused by ignition with an electric spark.

   Thus, this not only serves as a powerful source for ignition of the ambient mixture, but is also effective in preventing misfiring, fluctuation of the pressure inside the cylinder at each stroke, and fluctuation of the maximum pressure. .



   Fuel particles injected from nozzle 7 include those at low velocity or excessively tiny in size. These particulate contents tend to be easily entrained by vortex S. For example, as indicated by the dotted line W in Figure 20, they can

  <Desc / Clms Page number 52>

 take part in combustion instead of being retained or deposited and evaporated in the vicinity of the spark plug 11 and without being dispersed to waste from the stratified feed.



   The advantages that can be derived therefrom include increased efficiency and reductions in unburnt hydrocarbons in the exhaust.



   Even when the amount of fuel injected per cycle during full load operation is large, the combined action of the air flow S or s1 allows the fuel particles to be so completely dispersed that there is no air flow. danger of a faulty ignition due to excessive conservation of fuel around spark plug 11, although it should be noted that better results are obtained by replacing the process of injecting a large amount of fuel into the limits of a small crankshaft angle by injecting the same amount of fuel within a crankshaft angle of a certain extent. In such operations under heavy load, it cannot be overlooked that the combined use of two spark plugs
11 for simultaneous ignition gives satisfactory results.



   Although the two spark plugs in this embodiment are located on the axis line of the scavenging air stream, experiments have shown that they can give results as satisfactory as those stated above when placed. in the upper part 10 or the side wall part of the cavity 6, symmetrically with respect to the axis line.



   It should be taken into account, however, that this factor is closely related to the configuration of the cylinder head S.

  <Desc / Clms Page number 53>

 



   Further, with this embodiment, the squirting flow formed by the planar side portions 19,19 of the inner wall surface of the cylinder head 5 and the corresponding upper portion of the piston 1, produces a pair of vortices in the combustion chamber 20 during the compression stroke, in particular when approaching the end of this stroke, and the vortices as well as the turbulence produced are superimposed on the movement of the particles.



   The combined movements serve to promote the dispersion of the fuel particles along the upper part 10 of the inclined plane and in the vicinity of the deepest part 14 of the cavity, to avoid excessive consumption of the mixture in the vicinity of the line of. axis on which the spark plugs 11 and the nozzle 7 are located, and to push the laminated feed against the internal wall surface of the head 5.



   It is possible as a variable to intensify the squirting by shaping the flat side parts 19,19 of the head very closely to the upper plane around the upper dead center of the piston 1 or so as to decrease the clearance at the upper dead center. and, conversely, to weaken the giclecaeat, for example by gradually increasing the aforementioned clearance towards the center of the head, so that the stratified feed can instead be collected in the direction of the axis line. After firing, the combustion gas becomes lighter and moves towards the center of the vortex. or it is replaced by fresh air which forms a mixture with the fuel. in order to take part in the combustion.

   Thanks to the squirt formed by the inner surface of the cylinder head and the upper part of the piston, the mixture containing the fuel particles is suitably dispersed - or concentrated and it is then superimposed on the vortex S inside the cylinder.
 EMI53.1
 cylinder. This facilitc, ls cor..b1U: tion who knows the ignition.

  <Desc / Clms Page number 54>

 



   In FIGS. 22 to 25, another embodiment has been shown which, like that which has just been described, comprises a head 5 with a practically semi-spherical internal contour and which is fitted with an injection valve 17 in a suitable location, this valve being located such that the nozzle 7 at its end (shown as a nozzle with a suitably selected number of holes and associated injection angles) has a direction of injection at the end of the nozzle. 'against the direction of the sweeping air stream S. The semispherical inner wall of the head is formed with a sector-shaped cavity 6 and the tip of the nozzle 7 protrudes at a point which constitutes the pivot point of the sector. The cavity 6 is shallower at this location and the depth of the cavity increases towards the wall of the sector surrounding it.

   The upper part 10 which constitutes the sector is planar, while the wall 21 surrounding it is of cylindrical shape, in parallel association with the cylindrical wall surface 4 'of the cylinder.



   In this embodiment, the injection direction W from the nozzle 7 is substantially perpendicular to the axis of the injection valve 17 and directed towards the surrounding wall portion 21 of the cavity. The corner where the wall part 21 of the cavity 6 meets the sector part 10 is shaped as a suitably rounded corner 22 and the other end of the wall part 21 is shaped as a sharp marginal part 23.



   The opening angle of this sector varies according to the number of holes in the nozzle, the angle of divergence of the injection, the adaptation position of the injection valve, etc., but it is generally determined so that a layered feed can be formed with expansion

  <Desc / Clms Page number 55>

 suitable and a vortex drive in the cylinder-
In the illustrated embodiment, two spark plugs 11 are fitted on the upper part 10 of the sector plane in the vicinity of the two lateral edges of the sector cavity 6, in selected positions where they are not directly exposed to the main current. of purging air S or to the main vortex stream having the latter as its base in the cylinder,

   but on the contrary by protruding in a relatively calm atmosphere and in a suitably rich mixture.



   In the present case, the fine fuel droplets injected from the nozzle 7 are originally exposed to the air stream S and the spray is braked and spread. Some of the atomized fuel loses its life force and moves together with the air stream S, but the remainder continues in. Most of it progressing without completely losing its life force. As this remainder progresses, the cavity in the form of sector becomes deeper, so that the fuel is little affected by the direct action of the air stream S until it meets the surrounding wall part 21 of the cavity, where it loses its live force in the direction of progress.

   Then, part of the atomized fuel is dispersed along the surface of the wall, while the mass of the atomized fuel cups fills the cavity 6 and partially flows therefrom, in particular along the part of the wall at the same time. - tourante 21. On the other hand, the air stream S is interrupted by the marginal part 23, at the place where the line oe delimitation is discontinuous and there is established a loole turbulence which. in turn, attracts and mixes the mass of atomized fuel droplets.

   At this point, a mixing strip with a width practically equal to that of the cavity 6 is formed and it circulates

  <Desc / Clms Page number 56>

 -cule jointly with the air stream S in cylinder 4 (see figure 24). Although part of the mass of the injected droplets hits the surface of the wall and is deposited there, it is immediately vaporized because the mass is kept at a sufficiently high temperature and it joins the mass of the atomized droplets in. subsequent incorporation into the mixing tape or ribbon. Likewise, thanks to the heat of combustion after firing, the evaporation of the remainder of the fuel is favored and the resulting vapor takes part in the combustion.

   In addition, since there is no possibility that the injected fuel spurts out and is deposited directly on the inner wall surface of the cylinder, any disturbance of the lubrication is excluded despite direct injection into the cylinder.



   Although the temperature of the marginal portion 23 which protrudes into the combustion chamber 20 rises upon exposure to the combustion flame, this heat is removed by exposure to the vigorous flow of cold purging air and. by evaporation of the fuel. Therefore, the marginal portion 23 is suitably cooled and does not constitute a hot spot. The stratified clouds of the mixture thus produced circulate in conjunction with the air stream S but, as the stream swirls. i lie within a field of centrifugal force and are subjected to a suitable degree of mixing action and are broadly leveled along the inner wall surface of the head 5, thus producing a layered feed with increased richness to the region peripheral.

   Since the lamination is carried out such that the mixture is richer towards the outer side and the density per unit volume is also higher towards the periphery, the demand

  <Desc / Clms Page number 57>

 
 EMI57.1
 and the air supply reset for the fuel supply are naturally in equilibrium and the process of motions is stabilized. When a suitably stratified supply is forced in this way, it is simultaneously ignited by the spark plugs. ignition 11 in cavity 6 (i.e. by the
11 spark plugs / in the atmosphere where the mixture is relatively rich, apart from the passage of the vigorous current of air).



   With the initial increase, a powerful heat source is formed to ignite the mixture; poor who is around. The fuel supply being effected through the nozzle 7 under high pressure and the ignition being effected mainly with the mixture containing the finely atomized fuel droplets, no difficulty arises in the process. cold start and the engine can immediately be brought into operation under full load.



   The rate of pressure increase in the cylinder is relatively low and the operation is uniform.



   The embodiment which has just been described does not involve any squirting action and therefore no quenching on the squirting face. Further, since the combustion chamber 20 generally has an ideal semi-spherical contour, improvement in efficiency and reductions in unburnt hydrocarbons in the exhaust can be effectively and positively achieved.



   It should be noted that while the Schnuerle scanning system has been adopted in this embodiment, the air stream in the space within the head 5 will not always flow exactly along the path. axis line XX of figure 25, because of a slight difference between the

  <Desc / Clms Page number 58>

 wise to 'air' to the left and right as seen from case 12 and it is quite normal for the current to flow at a certain angle of deflection.

   Even in such a case. the cavity
6 acts suitably thanks to the wall part 23 surrounding it which extends widely in an arc¯ Thus, this production farm is insensitive to the deviation of the flow and the degree of disturbing effect on the production of the mixture n ' is that reduced or, in other words, the specific efficiency differences between the engines is negligible, in a beneficial way.



   Although the present invention has been described in connection with various embodiments thereof incorporated in two-stroke / electric ignition engines employing the schnuerle sweeping system it is equally applicable to engines. with a loop or cross scan system. Likewise, the ignition system is not limited to electric spark ignition and the adoption of other common means of ignition such as an incandescent spark plug, hot bulb or other ignition system. ignition, such as the Diesel system not calling for ignition from the outside, is not an objection.



   Since the engine according to the present invention works as previously described, stable combustion is obtained by changing the intake ratio in a wide range without any obstacle to combustion, because the swirling air stream contains a lot of gas. fresh air in the outer region, for example even when the air supply is throttled to a lower intake ratio. This is a very beneficial factor for an engine using a crankcase compression type sweeping system.

   Work

  <Desc / Clms Page number 59>

 lost for pumping by an engine in which loop or cross sweeping is used in the manner of a two-stroke engine, increases with the increase in the intake ratio and the ratio established between the Intake throttling and work lost for pumping is the reverse of that established in a four-stroke engine. It is therefore desirable that the intake throttle be made more intense with the reduction in load.

   On another side. the stratification of the feed aims to achieve an improved thermal efficiency and a purified exhaust thanks to the improvement of the specific thermal ratio of the active gas, a reduction in heat loss to the environment, an increase in speed of heat production due to reduction of thermal dissociation, etc., achieving stabilized combustion with lean mixtures in total. In this sense, it is desirable that the air-fuel ratio be as lean as possible in the range ensuring stable combustion and excluding supercooling, and it is practical to use an optimum air-fuel ratio (e.g. between 16/1 and 20/1) depending on the load and the number of revolutions.



   Likewise, as described in connection with the previous embodiments, even the fuel injected directly into the cylinder will not strike and deposit on the sliding wall surface of the piston and hence trouble which might otherwise occur in lubrication can be effectively prevented, which is a rational advancement. Furthermore. Since the ignition is carried out for the mist-like mixture containing the injected fuel in the form of finely atomized droplets and also the partially vaporized fuel, the distribution

  <Desc / Clms Page number 60>

 of fuel droplets is high and does not constitute an obstacle for cold starting.

   In addition, the stratified feed is positively formed up to an optimum state as already described and it is not necessary to resort to the very complex control having as a basis the adjustment of both factors namely the injection of the fuel, ignition and swirling air, which is often essential for the conventional combustion process. In other words, there is a wide tolerance between fuel injection and ignition and both can be varied and set in extended ranges independently of each other, according to the present invention. . This wide tolerance in turn provides considerable flexibility against deterioration of fuel spray.

   The deterioration, if it exists, cannot have any appreciable effect on the characteristics of the engine (this fact has been confirmed * by experience).



   The degree of feed into the vortex zone can also be quite well varied by suitably loading the contour and dimensions of cavity 6 and the process of injecting fuel from injection nozzle 7. therein. It is also possible to advance the crankshaft angle for injection priming and to widen the crankshaft angle for effective injection with increasing load, so as to form a similar mixture. to an uninterrupted and suitable fog in the current / swirl in the cylinder, under / heavy loads.

   This means that the utilization rate of the air inside the cylinder under heavy loads can be greatly improved. This allows the engine to work without any gene under virtually smoke-free conditions, even if the mixture is excessively rich when viewed in.

  <Desc / Clms Page number 61>

 his outfit. There is no danger that engine operation will be limited by exhaust smoke before the mixture becomes excessively rich throughout the entire cylinder, as is often the case with certain types of stratified fuel engines. Therefore, full load operations with excessively rich mixtures are made possible as is the case with conventional carbureted engines.



  Likewise, no accessories or similar additional elements are required for the net and simultaneous reductions of the three harmful constituents of the exhaust emissions, namely carbon monoxide, CO, hydrocarbons, HC and nitrogen oxides, NOx, which are known sources of danger to the public and thus the present invention contributes to a great extent to the general purification of exhaust gases from internal combustion engines.



   It should be understood that the present invention is in no way limited to the above embodiments and that many modifications can be made thereto without departing from the scope of the present patent.

** ATTENTION ** end of DESC field can contain start of CLMS **.

 

Claims (1)

Claims 1. A stratified fuel type internal combustion engine, characterized in that in the vicinity of a cylinder head having a reciprocating piston and a cylinder with an exhaust port and a scanning port intended to be opened or closed by the movement. of the piston, there is provided an injection nozzle for supplying fuel to the cylinder and an ignition part, such that fuel from the injection nozzle is injected and supplied against or following the direction of a stream of fresh air having as its base the sweeping in said cylinder or in a swirling air current having as its base the current in said <Desc / Clms Page number 62> cylinder. to provide a combined action for the stratification of the combustible mixture along the inner wall surface of the cylinder head and subsequent ignition. 2. Internal combustion engine of the stratified fuel type, with a loop or cross sweep system. characterized in that an injection nozzle for supplying fuel to the cylinder as well as an ignition part are arranged in the cylinder teta forming part of the combustion chamber of the engine and from this nozzle injection, an injected mass of fine droplets of liquid fuel or an injected stream of gaseous fuel is projected and introduced in the direction or at 1% against the direction of a stream of purging air in the cylinder or of a stream of swirling air having as a basis this current in the cylinder, or alternatively both, so that the mixture with air of the fine droplets or the atmosphere and its evaporation can be stratified and: spread to be then ignited in the cylinder head. 3. Internal combustion engine of the stratified feed type with a loop or cross scanning system, according to either of claims 1 and 2, characterized in that there is provided a combustion chamber defined between a cylinder. engine and a piston for reciprocating the cylinder. and an injection nozzle for supplying fuel to the combustion chamber as well as a spark plug therefor are fitted in the head of said cylinder, the inner wall of the cylinder head being shaped with a: : ! cavity which is not directly exposed to the main air stream generated in the cylinder and which is capable of retaining the atomized droplets of fuel introduced, the injection of fuel from the injection nozzle being directed either towards the <Desc / Clms Page number 63> inner wall surface of the cavity or in the cavity. 4. Internal combustion engine of the stratified feed type with a loop, cross or other scanning system according to claim 1 or 2, characterized in that an injection nozzle for the supply of fuel. fuel in the cylinder as well as a spark plug for it are arranged in the cylinder head which constitutes the combustion chamber of the engine and, before the injected mass of fine droplets of fuel coming from the nozzle of injection is projected in the direction or against the direction, while being introduced and mixed, of the current of sweeping air or of the swirling air current having as a base this in the cylinder, or even both, the fuel is injected directly into the cavity formed in the cylinder head and is dispersed there, in order to promote taper formation of the stratified feed and to limit wastage by dispersing the injected fuel droplets into the combustion chamber having the cavity, thereby to stratify the fuel mixture as a ribbon in the combustion chamber and set this one on fire. 5. Internal combustion engine of the stratified feed type, with a loop, cross or other scanning system according to either of claims 1 and 2, characterized in that the head of the cylinder which constitutes the chamber of engine combustion is shaped with a recessed cavity from the inner wall surface of the cylinder head and an injection nozzle for supplying fuel to the cylinder as well as a spark plug therefor. arranged in the cavity, and the injected mass of fine atomized fuel droplets from the injection nozzle or this mass of droplets and the vapor from the surface of the wall or from a mixture <Desc / Clms Page number 64> of this mass of droplets and vaporized fuel, is maintained temporarily with increased mixing density in said cavity and then is entrained over the scavenging air stream or a swirling air stream based thereon in the cylinder, or both, as such. so that the mixture could be laminated and mixed in ribbon form along the inner wall surface of the cylinder head, to be finally ignited. 6- Internal combustion engine of the direct injection type, having a reciprocating piston, a cylinder having an exhaust port and a scanning port intended to be / opened or closed by the movement of the piston, and an injection nozzle for supplying fuel to the cylinder as well as a spark plug, characterized in that the cylinder head is formed with a pocket recessed with respect to its internal wall so as to be separated direct exposure to the main air stream produced in the cylinder and capable of temporarily retaining the atomized fuel droplets supplied. and a squirting flow formed by the inner wall surface of the cylinder head and the upper part of the piston head is superimposed and made to join with the sweeping air stream or a swirling air stream based on this in the cylinder, in order to disperse, rarefy or concentrate the mixture of injected fuel droplets and their vapor for efficient stratification of the feed. 7. Internal combustion engine of the stratified feed type, with a loop, crossed or other scanning system, according to either of claims 3 and 4, characterized in that an injection nozzle for the fuel supply <Desc / Clms Page number 65> and an ignition part are arranged in the head of the cylinder which constitutes the combustion chamber and the mass of the fuel droplets injected from the injection nozzle is injected against and / or along the direction. scavenging air stream or swirling air stream based thereon in the cylinder, or both, while the resulting combined action is used to spread the mixture of atomized fuel droplets and their vapor along the inner wall surface of the cylinder head, in order to thus achieve the stratification of the feed. A reciprocating piston type stratified feed engine according to either of claims 5 and 6, characterized in that a single combustion chamber is provided, defined between the inner wall surface of the cylinder. cylinder head receiving a piston and the upper part of the piston head, the cylinder head being shaped with a recess retracted from the internal wall surface of the head, cavity which is large enough to contain the atomized fuel droplets introduced and fuel from the injection nozzle is injected directly into said cavity to effect dispersion and mixing to promote the mixing action efficient stratified feed and limited wasted scattering of atomized fuel droplets, the fuel mixture being stratified in the combustion chamber by any one or a combination of dispersing, mixing, stratification, stabilization and entrainment by the air stream as the fuel droplets circulate with the scavenging air stream caused by the piston and / or the swirling air stream based <Desc / Clms Page number 66> this current, after which the mixture is set on fire 9. A stratified feed engine of the direct fuel injection type according to any preceding claim, wherein the cylinder head which constitutes the combustion chamber of the engine is provided with one or more injection nozzles. for supplying fuel to the cylinder, characterized in that the inner wall surface of the cylinder head is shaped into a semi-spherical or other curved contour and is formed * with a cavity still recessed from the already curved surface, this surface receiving a configuration with round or sectoral areas or other relatively strongly curved peripheral areas effective for stratification ', so that a wasteful scattering of the atomized fuel droplets supplied by the injection nozzle (s) can be avoided and the dispersion and mixing of fuel with air can be promoted. 10. An internal combustion engine of the stratified feed type, adapted for a loop, cross or other scanning system, according to either of claims 8 and 9, wherein the head of the cylinder which constitutes the chamber of combustion engine is provided with one or more injection nozzles for supplying fuel to the cylinder, characterized in that the inner wall surface of the cylinder head is shaped into a semi-spherical or other contour and is formed with a obviously deeper than the already curved inner wall. the cavity having a configuration offering round, semi-spherical, sector or other relatively strongly curved peripheral areas effective for stratification while exhibiting an irregularity at the base, between deep and shallow areas, <Desc / Clms Page number 67> as well as with a protruding point for producing local turbulence upstream or downstream with respect to the scavenging air stream in the cylinder or a swirling air stream based on the stream in the cylinder, means being provided to allow the local turbulence thus produced to facilitate the mixing, the dispersion and the rarefaction of the air and of the mass of fuel droplets containing their vapor, in order to effect a stratification of the mixture and a subsequent ignition of it this. 11. Engine, internal combustion of the stratified fuel type, as described above or in accordance with the accompanying drawings BAD ORIGINAL