WO2004106715A1 - Four-stroke combustion piston engine with a two-part cylinder chamber - Google Patents

Abstract

The invention relates to a four-stroke combustion piston engine with a two-part cylinder chamber. The cylinder chamber is subdivided by the piston (14) into a top cylinder chamber (ZO) and a combustion chamber (HR). The piston (14) has at least one inlet valve (53) and the combustion chamber (HR) has at least one inlet valve (10) in the area of the cylinder base. In conventional motors, the suctioned air is not sufficiently dense and is too warm due to a lack of space in the cylinder head. Furthermore, throttling due to the narrow flow cross sections during charge changes impairs the performance of the motor. The motor construction according to the invention eliminates particularly the problem of lack of space in the cylinder head thereby enabling the intake of dense and cold air. The exhaust gases come out of the cylinder (13) through the outlet valve (10) in the cylinder base. The motor can be operated with a two-step combustion process. Combustion only takes place in a separate combustion chamber during partial charge operation, fuel being injected into said chamber during the compression cycle.

Description

 Combustion 4-stroke piston engine with two-part cylinder space

The invention relates to a 4-stroke ner internal combustion engine according to the preamble of patent claim 1.

Aspects that play an important role in Nerbrenner 4-stroke piston engines with an open process and internal Nerbrenner are the cylinder filling with a fresh charge of optimal temperature and density as well as the optimal Nerburn of the air-fuel mixture in the cylinder for a given engine load states. These aspects are directly related to the engine's performance, its fuel consumption and exhaust emissions.

It is known in the prior art that air can be drawn into the engine or the engine can be charged:

“The power of an engine is proportional to the air flow. Since this is proportional to the air density, the performance of a motor specified in terms of stroke volume and speed can be increased by norcompressing the air before entering the cylinder, ie by charging. The degree of charging gives the increase in density compared to Naturally aspirated engine. It depends on the charging system used (achievable pressure ratio) and is greatest at a given pressure increase if the temperature of the compressed air (charge air) is not increased or is cooled back to its initial temperature by the charge air cooling. The degree of charging is limited in the gasoline engine by knocking combustion, in the diesel engine by the maximum permissible peak pressures. "(Robert Bosch GmbH, Stuttgart. (1995). Automotive paperback [KTT]. Augsburg: Weltbild - p. 378).

Engines without air charging (naturally aspirated engines without pre-compression) for cars and trucks are currently only being built a little. The new generation of engines has either dynamic or mechanical charging.

The principle of dynamic charging is the conversion of the suction work of the piston into the kinetic energy of the gas column in the inlet channel upstream of the inlet valve, the kinetic energy being converted into the work of compression of the fresh charge.

Mechanical charging by means of charging devices is the same task, but mechanically a correspondingly dense fresh charge, which is under a slight positive pressure, is brought into the inlet channel upstream of the inlet valve.

In all supercharging systems and also in normal intake systems, the fresh charge is prepared in the intake port and drawn into the cylinder by the pistons during the intake stroke after the intake valve is opened. Nevertheless, the correct course of the cylinder filling is difficult due to the lack of space in the cylinder head and other related problems.

As is known (Bosch GmbH, KTT pp. 395 - 396), the upper part of the combustion chamber belongs to the cylinder head and closes the cylinder tube at the top, whereas the lower part of the combustion chamber by the piston top side forms. In the cylinder head there are gas exchange elements (mostly with control), inlet and outlet channels, candle (spark or glow plug) and possibly injectors. All bores for intake and exhaust valves, candles and injection valves must be arranged with their openings in the upper part of the combustion chamber. For a given cylinder diameter, it is therefore not possible to place correspondingly large valve diameters.

The lack of space in the cylinder head also limits the course and size (cross section) of the intake and exhaust ports. Therefore, the intake port in the cylinder head is generally not large enough

(in terms of its cross section). The volume of the inlet channel is also several times smaller than the volume of the cylinder. The pressure of the fresh charge in the inlet duct therefore drops significantly during the intake stroke. The pressure in the cylinder drops even more because the flow of the fresh charge is throttled by the inlet valve in the way. As a consequence, after the intake valve is closed, a fresh charge, which is significantly thinner than the density in the intake manifold, remains in the cylinder.

Due to the lack of installation space for the ducts in the cylinder head, there are also obstacles during the extension stroke. As from the 4-stroke

The known method (Bosch GmbH, KTT, p. 374) opens the exhaust valve shortly before bottom dead center and, in the case of supercritical pressure conditions, approx. 50% of the combustion gases leave the combustion chamber during this pre-discharge. The piston moving upwards then ensures that the combustion gases are almost completely removed from the cylinder, ie from the main combustion chamber, during the exhaust stroke.

However, complete removal of the fuel gases from the cylinder cannot be achieved in this way. A considerable amount of exhaust gas remains in the cylinder, which cannot escape quickly enough due to the narrow gap between the exhaust valve and the valve seat. As the piston continues to move upward, residual exhaust gas compression occurs. tung. The residual exhaust gas is under pressure and “if the intake valve opens shortly before top dead center of the piston (with the exhaust valve still open), the exhaust gases flow directly from the combustion chamber into the intake duct or from the exhaust duct back into the combustion chamber and then into the intake duct. This 'internal' exhaust gas recirculation takes place especially at partial load and during idling and has an unfavorable effect. "(Bosch GmbH, KTT, p. 375).

Due to a high intake manifold vacuum, this effect has a particularly negative impact on throttle-controlled gasoline engines. In engines with mechanical supercharging, the pressure in the intake manifold and in the inlet duct is greater than in intake manifolds of throttle-controlled engines, as a result of which this effect of exhaust gas recirculation also occurs, but with less impact.

The fact that the air density is temperature-dependent has a significant impact on engine performance (torque), fuel consumption and exhaust gas emissions. The denser and colder (up to a corresponding value) the fresh charge is sucked or charged to the cylinder, the greater the engine output (see Bosch GmbH, KTT, p. 402).

With conventional engines, the fresh charge warms up as it flows through the narrow intake ports into the hot cylinder head. Significant heating occurs at the transition to the inlet channel neck, where the inlet valve is installed. The inlet duct neck and inlet valve are the warmest point in the inlet duct. During this transition through the inlet channel neck, in addition to the heating of the fresh charge, there is a significant cooling of the inlet valve and the

Upper combustion chamber area. The cooling of the upper combustion chamber wall in turn has a negative influence on the evaporation of the fuel, which takes place at the beginning of the combustion process. As the fresh charge heats up, its density drops, which reduces engine performance. The air-fuel mixture becomes richer as the air density decreases (see Bosch GmbH, KTT, p. 402).

Another reason for the warming of the air is the mechanical charging in the charger due to air compression. The factors that cause the fresh charge to dilute and warm up during the intake stroke reduce engine performance and consequently lead to greater fuel consumption and increased exhaust gas emissions.

The course of the combustion process in the combustion chamber of engines with a homogeneous air-fuel mixture depends on the temperature of the intake air, the temperature of the combustion chamber wall and the contamination of the fresh charge by the exhaust gas residues.

To produce a combustible, homogeneous air-fuel mixture, all of the fuel must have evaporated before the ignition is initiated (see Bosch GmbH, KTT, p. 364). If the air temperature is too low - due to air that is too cold or the combustion chamber walls are too cold - the evaporation and consequently the combustion does not take place completely. With this incomplete combustion, engine output drops dramatically while fuel consumption and exhaust emissions increase.

A further hindrance in the combustion process for engines operated with a homogeneous air / fuel mixture can occur if the mixture in the combustion chamber reaches values (parameters) which cause knocking combustion. “Knocking combustion is used when flame speeds in the range of the speed of sound occur. This can occur especially towards the end of combustion, when the tail gas is already highly compressed and has high temperatures. "(Bosch GmbH, KTT, p. 366). Although not yet captured by the flame front, the tail gas ignites due to the energy input from the sound wave and burns at a very high burning rate (explodes), which causes a pressure wave at high frequency and consequently leads to thermal and mechanical damage to components (pistons, Seal, bearing) leads. The causes that promote this type of combustion, among others, are the excessive distance from the ignition source to the tail gas and the excessive temperature of the tail gas, which is taken from hot parts of the combustion chamber. The hot parts are mostly the exhaust valves that are removed from the ignition source.

Even with engines operated with heterogeneous air-fuel mixtures, there is not optimal combustion with harmful consequences. After the start of combustion (see Bosch GmbH, KTT, p. 372), that part of the fuel that evaporates during the ignition delay and is mixed with air burns very quickly. If this proportion is very high, a "hard" combustion with corresponding negative effects can result.

The shorter the ignition delay, the less fuel can evaporate before the start of combustion, which reduces the formation of the air-fuel vapor quantities. The cause of the long ignition delay is the sudden drop in temperature during the injection, because the fuel injected and atomized under high pressure requires heat to evaporate.

The first injected fuel drops fly through the air and evaporate. During the flight they take heat from the hot air to evaporate and at the same time use oxygen to burn it. The drops flying further back already have less heat and oxygen available and either fly further to get heat and oxygen or reach the wall of the combustion chamber and then evaporate there. As a result, the air temperature and the amount of oxygen in the entire injection zone drop so much that without Supply of heat and oxygen, the auto-ignition is significantly hindered.

This sudden drop in temperature and oxygen levels promotes the formation of fuel vapors which cause "hard" combustion. If there is no heat source in the immediate vicinity and the heat has to be transported through the air from distant zones of the combustion chamber, ignition delay and combustion take longer and do not show the normal course, but lead to sluggish combustion.

Against this background, it is an object of the present invention to provide a generic piston engine which, in particular due to the elimination of the space conditions in the cylinder head which are problematic for the gas exchange, provides optimal conditions for complete, maximally effective, "clean" fuel combustion, regardless of the engine load conditions and the speed of the engine, and with which the above-described unfavorable effects, in particular knocking combustion (in the case of engines operated with a homogeneous mixture) and "hard" combustion (in the case of engines operated with a heterogeneous mixture) are avoided.

In particular, the invention is intended to eliminate the described problems of heating the fresh charge that is too great due to lack of space in the cylinder head, and reducing the fresh charge density when it flows through the inlet channel to the cylinder. Furthermore, it should be possible to avoid or significantly reduce unfavorable effects such as the residual exhaust gas compression and exhaust gas recirculation during the exhaust stroke.

This object is achieved by an internal combustion engine having the features of patent claim 1. Preferred embodiments of the invention are the subject of the dependent claims.

The internal combustion engine according to the present invention comprises cylinders, pistons and crankcases in a manner known per se. According to the invention, however, the internal combustion engine is characterized in that the cylinder space is subdivided by the piston into a cylinder head-side cylinder upper space and into a combustion chamber on the crankcase side. In this case, the inlet valve or the inlet valves are installed in the piston, which enables gas to pass between the cylinder upper chamber and the combustion chamber. The combustion chamber is delimited by the piston crown, cylinder wall and cylinder crown and has at least one exhaust valve in the area of the cylinder crown.

The inlet valve built into the piston or those built into the piston

Inlet valves enable the cylinder or combustion chamber to be filled with fresh charge, in that the movement of the piston over-pumps or displaces the fresh charge from the cylinder upper space through the inlet valve in the piston to the combustion chamber.

In particular, since the filling of the combustion chamber and the exhaust gas emission do not take place at one and the same end of the combustion chamber as in the prior art, but according to the invention at opposite ends of the combustion chamber, there is a considerably larger installation space available for the gas exchange elements and for the corresponding gas routing channels.

Due to the possible significant improvement in the cylinder or. Combustion chamber filling initially achieves a higher engine torque in the entire speed range and thus an increase in output.

In the absence of any throttle elements, the torque in the internal combustion engine according to the invention is only dependent on the amount of fuel injected. The exhaust gases can also, in particular Due to the much larger flow cross sections of the gas exchange elements compared to the prior art, remove almost completely from the cylinder during the exhaust stroke without residual exhaust gas compression and exhaust gas recirculation effect. The mechanical friction losses and the losses due to gas resistance during the intake stroke and the exhaust stroke are also significantly lower than in known internal combustion engines.

In particular, due to the arrangement of the inlet valve or the inlet valves in the piston (i.e. on the combustion chamber ceiling) and the outlet valve or the outlet valves in the region of the combustion chamber floor, it is achieved that correspondingly cold and dense air during the

Intake cycle can flow almost independently of the engine load conditions and almost unthrottled into the combustion chamber of the cylinder and can be charged.

In addition, this charge has a stratified charge structure with turbulence in the stratified area in the combustion chamber after overflow through the piston. This means that the warmest layers are on the combustion chamber floor and in the area of the exhaust valves, while layers that are colder and colder follow towards the top of the piston. This stratified charge enables complete, economical and clean combustion in all engine load conditions, at the same time prevents knocking combustion in engines operated with a homogeneous air / fuel mixture and limits hard combustion in engines operated with a heterogeneous air / fuel mixture.

In addition, the special flow conditions in the cylinder of the internal combustion engine according to the invention make it possible to use fuels other than petrol or diesel oil. Fuels can be used which can contain, for example, water or various ashes (eg silicates) as combustion products. With the downward extension and the additional flushing effect of the flow guide according to the invention, these combustion products can be removed easily and completely, with few or there is no contamination of the cylinder tube, pistons and intake valves.

In addition, due to the motor construction according to the invention, the cylinder can also be made from building materials other than those which are currently in use, in the form of a completely separate component, e.g. made of ceramic.

If, as is provided in accordance with a particularly preferred embodiment of the invention, the engine comprises an air circulation pipe between an air outlet valve and an air inlet valve, particularly good dynamic air charging is achieved even at a low engine speed. Air is drawn into the cylinder head from the intake manifold not only every second, but every revolution of the crankshaft through 360 °. The additional air intake during the compression cycle causes the air flow in the intake manifold to reach a speed that is approximately twice as high as the speed in intake manifolds at the same engine speed in conventional engines.

At higher engine speeds, a significant dynamic boost with appropriate pressure is achieved without additional chargers and with minimal engine power losses, because the throttle losses during the flow through the large cross-sections in the intake manifold, air intake ducts and intake valves are low despite high air speeds.

An additional advantage of the design with air recirculation pipe is that the air from the cylinder head, which was sucked in during the compression stroke, is pumped over the recirculation pipe to the intake pipe during the combustion stroke, where it in turn increases the air charge. For this purpose, the piston sucks two times dense and cold air from the intake manifold to the cylinder head during the 4-stroke cycle. Once the piston pumps the air through the intake valve in the piston to the main combustion chamber, where it is in the combustion process is used, the second time the air is pumped over the circulation pipe to the intake manifold, which results in a high air speed and thus a good dynamic air charge.

According to a further embodiment of the invention, part of the air from the cylinder upper chamber can also be transferred to the exhaust pipe so that the catalytic converter can cool down. The size of the proportion of air that is pumped over to the exhaust pipe depends on the air temperature and can be controlled, for example, by a thermostat in the circulation pipe.

The division of the combustion chamber into the main combustion chamber and combustion bowls or main combustion chamber and separate combustion chamber, which is provided according to further preferred embodiments of the invention, has particular advantages in the area of the combustion process. After the fuel injection, combustion processes take place in the combustion bowls or in the combustion chamber in the cylinder base, which produce a lot of heat in a short time due to complete fuel combustion, which results in high pressure in the cylinder and high torque.

On the one hand, this is achieved by the fuel evaporating quickly and completely because the air heat is properly distributed and hot

The combustion bowl walls or combustion chamber walls in the vicinity of the injection nozzle (with very little local cooling during the injection) promote good evaporation. In addition, because of the large excess of air associated with this embodiment, the exhaust gas temperatures and exhaust gas emissions - although the temperature becomes correspondingly high during combustion - are reduced in comparison with conventional engines. In addition, the composition of the exhaust gas emissions is "cleaner" due to the good conditions for after-reactions during the combustion and exhaust cycle. Optimal combustion of the air-fuel mixture is likewise achieved in these embodiments, the combustion taking place first in combustion bowls or combustion chambers and only then in the entire main combustion chamber.

In the embodiment with combustion chambers, pressure and heat of the exhaust gases generated in the closed combustion chamber during combustion are also used very well during part-load operation. After opening the combustion chamber, the exhaust gases transfer pressure and heat to the excess air in the cylinder, which is converted into additional work. At the end of the combustion cycle, the exhaust gases cool down considerably more than with conventional engines and are "cleaner" due to after-reactions that take place immediately after the combustion chamber opening (bowl separation) in contact with additional air in the cylinder.

In full-load operation, the two-stage combustion first results in a very good pressure distribution on the pistons in the combustion chamber and then also in the main combustion chamber and subsequently a very even increase in torque, which makes the engine elastic and powerful.

In the following, the invention will be explained in more detail with reference to drawings which merely show exemplary embodiments.

It shows:

Figure 1 in schematic representation of an embodiment of a motor according to the present invention in section through the cylinder center.

FIG. 2 in an enlarged representation corresponding to FIG. 1, the crankcase area and exhaust valves of an engine according to FIG. 1 when cut through the valve plane; 3 shows a schematic representation of the cylinder of an engine according to FIG. 1 in cross section looking from the cylinder head onto the cylinder bottom;

4 in a representation corresponding to FIG. 2 piston area of an engine according to FIG. 1 in section through the

Piston center;

5 in a representation corresponding to FIG. 3 cylinder with piston of an engine according to FIG. 1 in cross section looking towards the top of the piston,

6 in a representation corresponding to FIG. 2, the lubrication system of the piston of an engine according to FIG. 1 in an angled longitudinal section;

7 shows a schematic detailed illustration of the piston wall, cylinder wall and piston lubrication system of a further embodiment of an engine according to the invention in

Longitudinal section;

FIG. 8 in a representation corresponding to FIG. 4 piston area and piston lubrication system of an engine according to FIG. 7 in a graduated section through the piston center and valve;

9 in a representation corresponding to FIG. 5, cylinder and piston with intake valves in an engine according to FIGS. 7 and 8, in a graduated cross section with a viewing direction from the cylinder head;

Fig. 10 in a representation corresponding to Fig. 1 another

Embodiment for an engine according to the present invention in section through the cylinder center during the intake stroke; 11 shows an illustration corresponding to FIG. 1 of the engine according to FIG. 10 in a graduated section through valves and channels at the end of the combustion cycle;

12 in a representation corresponding to FIG. 10 of the engine according to FIGS. 10 and 11 in a section through the cylinder center during the compression stroke;

FIG. 13 in a representation corresponding to FIG. 3 cylinder of an engine according to FIGS. 10 to 12 in cross section looking from the cylinder head onto the cylinder bottom with exhaust valves;

14 shows a representation corresponding to FIG. 9 of the cylinder and piston with intake valves in an engine according to FIGS. 10 to 13, in cross section with the viewing direction from the cylinder head;

FIG. 15 in a representation corresponding to FIG. 4 piston area of an engine according to FIG. 10 in a stepped section through valves and combustion chamber;

16 in a representation corresponding to FIG. 15 piston area according to FIG. 15 in section through the center of the piston;

17 in a representation corresponding to FIGS. 15 and 16, piston area according to FIGS. 15 and 16 including piston lubrication system, at the moment when the two combustion chamber troughs are separated in a longitudinal section through the piston;

18 in a representation corresponding to FIGS. 15 to 17, pistons according to FIGS. 15 to 17 including piston rods and cylinder hood in the longitudinal section of the piston; FIG. 19 shows a schematic illustration of an enlarged detail from an engine according to FIG. 10 in the area of the exhaust valves including the seal bushing package in a partially broken-away section;

20 shows a schematic illustration of a crosshead of an engine according to FIGS. 10 to 13 in cross section; and

21 in a representation corresponding to FIGS. 15 to 17, piston area of a further embodiment of an engine according to the invention with combustion chamber troughs in longitudinal section.

1 to 6 show a first exemplary embodiment of an engine operated with a heterogeneous air / fuel mixture (e.g. diesel oil) as a direct injector with two independent lateral combustion bowls.

Fig. 1 shows in section A - A (see Fig. 3), the section running through the middle of the cylinder, the crankcase 1, in which the crankshaft 2 with bearings, two camshafts 3 (for the exhaust valves 10) with bearings, two guide strips 4, guide bush 5, two injection nozzles 6, two glow plugs 7, two rocker arm axes 8 and the seal 12 are installed. The crankcase 1 is closed from below, as in conventional engines, with an oil pan 9. At the upper part of the crankcase 1 there are connection grooves in which the cylinder 13 is centered and sealed.

The area in the middle of the round centering and sealing groove serves as a cylinder base, which has two combustion bowls. The injection nozzles 6 and the glow plugs 7 are connected to the combustion bowls. In the middle of the cylinder base there is a bore for the guide bush 5 of the piston rod 17. The piston rod 17 and two separating ribs (see FIG. 3) "divide" the cylinder base into two "half-cylinder bases". Each "half-cylinder base" has an injection nozzle 6 and a glow plug 7. Below the cylinder base there are cooling channels (water space) which cool the entire upper area of the crankcase 1. There is a window on each side of the crankcase 1 through which access to the control members of the outlet valves 10 (see Fig. 2) The windows are closed with covers 11.

The cylinder 13 is fastened to the crankcase 1 either as a single tube with the water jacket cooling or as a cylinder block.

The piston 14 is located in the cylinder 13 with a cross insert 15 screwed into the center, in which components of the piston lubrication system (see FIG. 6) are installed. The piston crown has an opening (for the piston rod 17), which is also the inlet valve seat. In the space between the piston crown and cross insert 15, an inlet valve plate 16 is inserted, which is attached to the piston rod 17 with the threaded pin 18.

The inlet valve plate 16 can move in this space together with the piston rod 17 either upwards or downwards and thus defines the stroke of the inlet valve. When the piston rod 17 moves downward, the inlet valve plate 16 closes the opening in the piston head (inlet valve closed) and can thus pull the piston downward. When the piston rod 17 moves upward, the inlet valve in the piston head opens, the inlet valve plate 16 presses on the cross insert 15 and can thus push the piston upward.

The piston rod 17 is connected to the crankshaft 2 by the crosshead 19 and the connecting rod 20. The crosshead 19 has two lateral carriages that guide the piston rod 17 between the guide strips 4.

The slide from the crosshead 19 and the guide rails transmit the side forces caused by the gas force during the combustion cycle in the cylinder 13 and by the mass forces during the movement of the

Engine components arise on the supporting structure of the crankcase 1.

The cylinder hood 21 closes off the cylinder tube 13 from above and accommodates the large air inlet valve 22 and the large air outlet valve 23 with the associated springs, the piston stroke limiting sleeve 24 and the screw-in guide bush 26. In the piston stroke limiter sleeve 24 there is the stop nut 27, which is connected by the tension rod 25 to the cross insert 15 in the piston.

A disc spring is installed between the piston stroke limiter sleeve 24 and the collar of the stop nut 27. There is also a spiral spring between the screw-in guide bush 26 and the collar of the piston stroke limiter sleeve 24. The two springs reduce the shock that occurs at the end of the extension stroke when the piston 14 reaches its lowest position, so that the flushing gap can open.

The cylinder hood 21 and the piston top form the cylinder upper space ZO. The piston underside (piston crown) and the cylinder crown form the main combustion chamber HR (see Fig. 6).

The camshaft 29 of the large air inlet valve 22 is located on one side of the cylinder hood 21, and the camshaft 30 of the large air outlet valve 23 is located on the other side. Each of the two camshafts 29, 30 is installed in a housing 31. The housings are filled with lubricating oil and fastened to the intake pipe segment 32 or to the air circulation pipe segment 33. The two segments 32, 33 are laterally connected to the cylinder hood 21. The cams 29, 30 control the large air valves 22, 23 each via a bolt 28 which is screwed into the center of the valve 22, 23 in each large air valve 22, 23. At the same time, the large air valves -22, 23 are guided and centered by the bolts 28. The bolts 28 have a rectangular cross-section and on the side facing the camshaft 29, 30 a built-in roller which rolls over the cams 29, 30 and which transmits the pressure of the valve spring to the cams 29, 30.

The suction pipe 34 is connected to the suction pipe segment 32, the air circulation pipe 35 is connected to the air circulation pipe segment 33.

FIG. 2 shows in section BB (see FIG. 3), the section running through the outlet valves 10 and the outlet channels, the installation of outlet valves 10 with valve control and outlet channels. The exhaust valve seats 36 are recessed in the cylinder bottom. Each exhaust valve 10 in the crankcase 1 is guided and sealed by a valve guide sleeve 37. The exhaust valve 10 is actuated by the camshaft 3 through the rocker arm 38 and via the valve lifter nut 39 and pulled back to the seat 36 with the valve spring 40. At the connection of the cylinder 13 to the crankcase 1, connections between the cooling in the cylinder water jacket and the cooling in the crankcase 1 are shown. There is a separating rib in the middle between the exhaust valve seats 36 in the cylinder base.

Fig. 3 shows in section CC (see Fig. 2) a view of the cylinder bottom. It shows four exhaust valves 10 and four exhaust valve seats 36, two combustion bowls with the glow plugs 7, a section through the piston rod 17 and two separating ribs on the cylinder bottom ,

The combustion bowl and two exhaust valve seats 36, which are recessed in the cylinder base, form a lateral combustion chamber base, which is located on one half of the cylinder base. An identical mirror image is arranged on the second half of the cylinder base Combustion chamber floor. The two combustion chamber floors are delimited from one another by the piston rod 17 and the separating ribs.

An exemplary embodiment for a fuel injection is drawn into the combustion chamber floors. It is carried out in three beam directions: two lateral in the horizontal plane and one in the vertical plane. The arrows show the fuel jet during injection and the turbulence caused by it.

4, the piston 14 is drawn in its lowest position at the end of the extension stroke in section D - D (see FIG. 5); there is a gap between the valve seat in the piston and the inlet valve plate 16. The section in FIG. 4 runs through the "windows" in the piston, combustion bowls, injection and suction cylinders of the piston lubrication system in the cross insert 15, injection nozzles 6, piston rod 17 with inlet valve disk 16 and threaded pin 18.

The injection pistons 41 and the suction pistons 42 of the piston lubrication system are screwed into the threaded pin 18. The holes for the lubricant are shown in the threaded pin 18. The two injection and suction cylinders of the piston lubrication system serve simultaneously as shock absorbers during the closing and at the end of the full opening of the intake valve 16 (they reduce the impact of the

Inlet valve plate 16 on the piston 14 and the cross insert 15). The further downward movement of the piston is limited by the pull rod 25, which is screwed onto the threaded nipple of the cross insert 15. The piston 14 has two oil control rings 43 and two piston sealing rings 44. Between the oil control rings 43 there is a groove for lubricant.

FIG. 5 shows a top view of the piston 14 and of the cross insert 15 screwed into the center of the piston with lubricating oil bores and lubricating oil valves in the piston lubrication system on the basis of the cross section E - E through the cylinder 13 (see FIG. 4). The piston 14 and the Cross insert 15 have four common threaded connections, but only in the area of the ribs. Between the ribs there are "windows" through which air can enter the space between the piston crown and cross insert 15 and can be pumped over to the main cylinder combustion chamber HR when the inlet valve 16 is open. The holes and one-way valves for the piston lubrication system are shown in the ribs (dashed lines) A cross section through the tension rod 25 can be seen in the middle of the cross insert 15.

6 shows the piston 14 during the intake stroke on the basis of the sectional representation F - F (see FIG. 5). The section in FIG. 6 runs through ribs, injection and suction cylinders of the piston lubrication system in the cross insert 15, through the piston 14 in the cross insert rib area and through the lubricating oil channels and lubricating oil valves of the piston lubrication system in the threaded pin and in the piston rod 17.

The inlet valve 16 is fully open here. The inlet valve plate 16 presses on the cross insert 15 and can push the piston 14 upwards. The injection piston 41 and the suction piston 42 of the piston lubrication system are in their highest position. In the middle of the injection piston 41 there is a bore through which the oil mist (oil-air mixture) from the oil atomizer 45 in the piston rod 17 can be sucked in through the bore in the threaded pin 18. At the top of the injection cylinder of the piston lubrication system there is a horizontal bore in the piston 14, which is drilled through the center of the ribs in the cross insert 15 and is provided on both sides with one-way valves which are sealed with threaded plugs. There are vertical connecting bores between the threaded plugs and the balls of the one-way valves, which are sealed from below with threaded plugs and which connect with oblique bores which lead to the lubricating groove of the piston 14. When passing through the thread between the piston and cross insert 15, conical screw-in Sets 46 (with a hole in the middle) screwed in. The conical screw-in inserts 46 seal the transition through the thread between the piston 14 and the cross insert 15 and at the same time fix their mutual position.

The suction cylinder in the cross insert 15 of the piston lubrication system also has holes through which it can extract used lubricating oil from the lubrication groove and the oil scraper rings 43: two vertical holes which are drilled upwards from the suction cylinder and have a connection to short horizontal holes which are connected to the outside thread of the Guide cross insert 15 towards the center of cross insert 15 and are sealed from the outside with a threaded plug. The horizontal short holes are also made in the center of the rib of the cross insert 15 and at the same height as the injection holes drilled through the center, but in the ribs rotated by 90 ° to the above. With these holes, other vertical holes are connected, which have one-way valves and are sealed from below with the thread plug. There are horizontal bores behind the one-way valves with conical screw-in inserts 47. They are similar to those of the screw-in inserts 46 and have the same function as these.

In the piston 14 behind the screw-in inserts 47 there are vertical bores sealed from above with plugs, which have 43 further connections to the lubrication groove and to the two oil control rings.

In the threaded pin 18 there are lateral vertical bores through which used oil drawn off by the suction piston 42 to the suction cylinder of the piston lubrication system can be blown out to the piston rod 17.

At the bottom of the threaded pin 18 is a washer 48 with a spring, which serves as a one-way valve. 7 to 9 contain partial sections of a further exemplary embodiment (piston with four intake valves), in which an engine operated with a heterogeneous air-fuel mixture is shown as a direct injector with two independent lateral combustion bowls.

7 shows a partial section through the injection cylinder 49

Piston lubrication system that can be used in this embodiment (piston construction with four inlet valves in the piston). The section in FIG. 7 runs through the injection cylinder 49 in the piston lubrication system and the connection of the injection oil channel to the engine piston 52. The injection cylinder 49 is installed in the cylinder hood 50. At the top of the injection cylinder 49 there is a connection to a lubricating oil atomizer with a one-way valve. In the injection cylinder there are the injection piston 51 with a one-way valve and a hole in the middle through which the oil mist is injected from the oil atomizer to the piston 52. The injection piston 51 is screwed into the bottom of the piston 52. The oil mist is injected from the injection cylinder 49 to the lubrication groove in the piston through the bores in the piston 52.

8 shows the piston 52 as an exemplary embodiment with four inlet valves 53 on the basis of the sectional representation G - G (see FIG. 9). The section in FIG. 8 runs through piston 52, inlet valve 53 with inlet valve holders 54, 55, connection of the suction piston 61 to the suction oil channel of the piston lubrication system in the piston 52, and combustion bowls and injection nozzles 6. The piston 52 is at its lowest position at the end of the compression stroke. All intake valves 53 are closed. The inlet valves 53 are installed from the underside of the piston head and are fastened from the top of the piston by means of the inlet valve holders (lower 54, upper 55).

Each valve has a valve seat 58 which is pressed into the piston crown from below. The inlet valve holders 54, 55 are centered on the centering bolt 56 and are fastened thereon together with the pull rod 60. Untitled. A spacer sleeve 59 is located between the inlet valve holders 54, 55. The inlet valve holders 54, 55 are connected to one another by four pins 62. The centering pin 56 is centered from below in the threaded pin 57 by a guide with a rectangular cross section and secured against rotation. In the middle of the piston head there is a bore through which the piston 52 is fastened to the piston rod 17 with the threaded pin 57.

A connection of the suction piston 61 of the piston lubrication system is shown on the right-hand side of the sectional view according to FIG. 8. Through the hole in the suction piston 61 and holes in the piston 52, the used lubricating oil is sucked out of the lubrication groove and the two oil scraper rings 43 through the suction piston 61 to the suction cylinder.

FIG. 9 shows a stepped cross section H - H (see FIG. 8) through the cylinder 13, the centering pin 56, the spacer sleeve 59, the inlet valve stem 53, the injection pistons 51 and the suction pistons 61 of the piston lubrication system, the pull rod 60 and a view of on top of the piston 52, the inlet valve holders - upper 55, lower 54 (partial view), the threaded pin 57 and the inlet valves 53.

The mode of operation of the engine shown in FIGS. 1 to 6, which is operated with a heterogeneous air-fuel mixture in the 4-stroke process, is described below.

When the piston rod 17 moves downward together with the intake valve plate 16 attached to it (during the exhaust stroke), the piston 14, which is pulled downward by the intake valve plate 16, also moves and pushes the exhaust gases out of the main combustion chamber HR (between the underside of the piston and the cylinder bottom ) through the opened outlet valves 10 to the outlet channels. The exhaust gases have a significantly lower resistance than in conventional engines, because four exhaust valves 10 together result in a large exhaust cross section and short exhaust gas paths facilitate the extension. At the same time, the upper side of the piston sucks the air from the suction pipe 34 through the opened large air inlet valve 22 to the upper cylinder area ZO (between the cylinder hood 21 and the upper side of the piston) during the piston movement downward. The large air outlet valve 23 is closed.

When the piston rod 17, together with the inlet valve plate 16 attached to it, reaches bottom dead center, the piston 14, which is not connected to the piston rod 17, moves further downward due to inertia until it is stopped by the piston stroke limiter 24. During this further movement of the piston 14 downwards, a gap opens between the inlet valve plate 16 and its valve seat in the piston. Air flowing simultaneously from the intake manifold 34 to the cylinder upper chamber ZO is compressed in the cylinder upper chamber ZO due to rapid piston braking (dynamic supercharging effect). A portion of this air flows further through the gap between the inlet valve plate 16 and its valve seat in the piston into the combustion chambers and further through the still open exhaust valves 10 to the outlet channels. This air flowing through the gap flushes the entire main combustion chamber HR free of exhaust gases at the end of the exhaust stroke.

The intake stroke now begins and the exhaust valves 10 close. The piston rod 17 moves upwards from bottom dead center. The gap between the inlet valve plate 16 and its valve seat in the

The piston becomes larger and reaches its maximum opening when the edge of the intake valve plate 16 reaches the lower surface of the cross insert 15 (see FIG. 6). Simultaneously with the movement of the piston rod 17 from the bottom dead center to the point where the inlet valve plate 16 reaches the lower surface of the cross insert 15, the oil atomizer 45 in the piston rod 17 is compressed by the injection piston. ben 41 oil mist (oil-air mixture) sucked into the injection cylinder of the piston lubrication system in the cross insert 15.

This oil-air mixture is injected through bores and one-way valves into the lubrication groove in the piston. There, oil from oil mist settles on the cylinder wall and reduces friction when the piston moves. Parallel to the injection cylinder, the air-exhaust gas mixture extracted in the suction cylinder from the lubrication groove and two oil scraper rings 43 by the suction piston 42 is compressed with used oil. Then the air-exhaust gas mixture compressed with used oil is blown out through the bores in the threaded pin 18 and the one-way valve to the piston rod 17 and further through the bores in the piston rod wall to the crank chamber.

The suction cylinder has a stroke volume that is several times greater than that of the injection cylinder because air and exhaust gas are also sucked in during the extraction of used oil. At the beginning of the upward movement of the piston rod, the compression of the oil mist in the injection cylinder of the air-exhaust gas mixture in the suction cylinder causes the piston 14 to start moving upward, even though the edge of the inlet valve plate 16 has not yet reached the lower surface of the cross insert 15.

Shortly thereafter, the two cylinders 13 of the piston lubrication system over-pumped the oil-air-exhaust gas mixtures and now the edge of the inlet valve plate 16 presses on the lower surface of the cross insert 15 and pushes the piston 14 upwards. The large air inlet valve 22 closes when the piston 14 moves upward. Despite the fully open inlet valve 16 in the piston 14, the air in the cylinder upper chamber ZO is compressed and at the same time the air pressure under the piston 14 in the main combustion chamber HR drops.

The air flows from the cylinder upper chamber ZO via the inlet valve 16 to the main combustion chamber HR. The first portion of air (first layer) remains with Cylinder bottom and heats up from the hot surfaces of the exhaust valve 10 and the combustion bowl walls. This air has turbulence that was caused in the flow through the inlet valve 16 right at the beginning of the upward piston movement. The additional air that flows into the main combustion chamber HR remains under the piston crown of the piston 14 moving upward due to a suction effect and has much stronger turbulence, which is caused by a higher piston speed than at the beginning of the intake stroke.

During the further movement of the piston 14 upwards and the increasing amount of air, new turbulence is always formed.

Towards the end of the intake stroke, the speed of the piston rod 17 decreases when moving upwards and is zero at top dead center. At the same time, the piston 14, which is not connected to the piston rod 17, continues to move upward due to the inertial force until it is stopped by the valve disk 16. The shock between that

Valve plate 16 and its seat in the piston 14 is reduced by the damping effect of the injection and suction cylinder of the piston lubrication system and by the gas resistance of the air flowing to the main combustion chamber. The damping effect emanating from the injection and suction cylinder arises at the moment the inlet valve closes, where the injection piston 41 sucks the oil-air mixture from the atomizer 45 in the piston rod 17 over to the injection cylinder and the suction piston 42 the used lubricating oil together with air and exhaust gas from the Lubrication groove and the oil scraper rings sucked over to the suction cylinder.

The large air intake valve 22 opens while the intake valve is closing. When the intake valve in the piston closes, the intake stroke ends and the compression stroke begins.

The piston rod 17, which moves downward, pulls the piston 14 with the inlet valve plate 16 attached to it. The piston, together with the inlet valve plate 16, compresses the air in the main combustion chamber MR. At the same time, air flows from the intake manifold 34 into the upper cylinder space ZO, which is drawn in by the piston 14 moving downward. Shortly before bottom dead center, fuel is injected simultaneously from the injection nozzles 6 into the two combustion bowls, which are located in the middle of the combustion chambers, and is auto-ignited under very good thermal conditions.

The combustion cycle begins from the moment the fuel is injected into the combustion bowls. The large air inlet valve 22 closes and the large air outlet valve 23 opens. The first phase of combustion takes place in parallel in both combustion bowls, but the combustion spreads immediately to the combustion chambers (exhaust valve area). Then the flames from the two combustion chambers combine and spread over the entire main combustion dream. The two combustion sources quickly build up a large flame area and generate a lot of heat, so the pressure in the cylinder 13 increases rapidly. Air not used in the combustion process expands in the cylinder 13 and causes additional pressure.

Now the piston 14 together with the inlet valve plate 16 pulls the piston rod 17 upwards. The piston 14, the bottom surface of which is much larger than the surface of the inlet valve plate 16, exerts a greater tensile force, which ensures the correct closure of the inlet valve plate 16. The tensile force is transmitted from the piston rod 17 to the connecting rod 20, where it is converted into the torque of the engine. The resulting lateral forces are transmitted to the supporting structure of the crankcase 1 by the slides in the crosshead 19 and the guide strips 4. Due to very good lubrication conditions, the friction losses between the crosshead slide and the guide rails are low.

The piston 14, which moves upwards, forces the air out of the cylinder upper chamber ZO through the large air outlet valve 23 into the air circulation pipe 35. This air, which is forced out, partly reaches the Intake pipe 35, partly to the exhaust pipe. The decision depends on the air temperature (control with a thermostat) and the load state of the engine (control with a control system).

When the piston reaches its highest point - piston rod 17 top dead center - the combustion stroke ends and the exhaust stroke begins. At the same time, the large air outlet valve 23 closes and the large air inlet valve 22 opens. This opening is followed by the beginning of the 4-stroke process.

The difference between the exemplary embodiment according to FIGS. 1 to 6 and the exemplary embodiment according to FIGS. 7 to 9, the latter representing an engine operated with a heterogeneous air / fuel mixture, consists only in deviations in the design of the pistons, intake valves and piston lubrication system, the mode of action remains the same. The effects of the large air inlet and outlet valve as well as the outlet valves 10 are each identical.

When the piston rod 17 moves downward, the piston 52, which is firmly screwed into the piston rod 17 with the threaded pin 57, pushes the exhaust gases from the main combustion chamber HR through the exhaust valves 10 to the exhaust ports. The intake valves 53 are closed because there is a slight overpressure in the main combustion chamber HR and at the same time a small underpressure in the cylinder upper chamber ZO.

When the piston rod 17 together with the piston 52 reaches bottom dead center, the intake valves 53 with the intake valve package (intake valve holder 54, 55, pins 62, centering pin 56, spacer sleeve 59 and tension rod 60) continue to move downward under the action of the inertial force until they be stopped by the pull rod 60. During this downward movement, gaps open between the inlet valves 53 and their seats 58, which are pressed into the piston 52. Air flows through these gaps from the upper cylinder area ZO and pushes the exhaust gas residues from the two combustion chambers and combustion bowls through the still open exhaust valves 10 into the exhaust ducts.

At this moment the exhaust stroke ends and the suction stroke begins. The piston rod 17 with the piston 52 begins to move upward. The exhaust valves 10 close. The inlet valves 53 are still in their lowest position and move when the threaded pin 57 takes the centering pin 56 upwards. The air from the upper cylinder area ZO flows through the fully opened intake valves in the piston 52 into the main combustion chamber HR. The first air layer remains in the cylinder bottom and heats up due to the hot surfaces of the exhaust valve 10 and the combustion bowl walls. This air has turbulence created by the flow through the intake valves.

As the piston 52 moves upward, new layers with turbulence are always formed. These have no significant influence on the first layer that was created in the cylinder base.

When the piston rod 17 with the piston 52 reaches its top dead center, the intake valve package 54, 55, 62, 56, 59, 60 continues to move upward due to inertia until the intake valves 53 reach their seats. The shock between the intake valves 53 and their seats is reduced by the tension rod 60, which has a damper in the cylinder hood 50.

When the intake valves 53 are closed, the intake stroke ends and the compression stroke begins. The course of the compression stroke and the subsequent combustion stroke is the same as in the first exemplary embodiment described above.

The effect of the piston lubrication system in the second exemplary embodiment is described below. The piston has four connections for the lubrication system: two injection and two suction connections. The connections have the same distance from the center of the piston and are alternately placed at 90 °.

With each movement of the piston 52 downward, the injection piston 51 sucks the oil mist (oil-air mixture) through the one-way valves from the oil atomizer into the injection cylinder 49. When the piston 52 reaches its bottom dead center and begins to move upward, the one-way valve located at the oil atomizer closes and the one-way valve in the injection piston 51 opens. As the piston 52 continues to move upward, the oil mist in the injection cylinder 49 is sprayed through the bores in the injection piston 51 and piston 52 to the lubrication groove.

In parallel to the oil mist injection, the suction piston 61 sucks the used lubricating oil together with air and exhaust gas from the lubrication groove and the two oil control rings through the channels in the piston, the bore and the one-way valve in the suction piston 61 to the suction cylinder with each movement of the piston 52 downward.

When the piston 52 reaches its bottom dead center and begins to move upward, the one-way valve in the suction piston 61 closes and the one-way valve in the suction cylinder opens. When the piston 52 moves upward, the mixture consisting of used oil, exhaust gas and air in the suction cylinder is over-pumped through the one-way valve to the line for used oil. The suction cylinder has a stroke volume that is at least twice as large as that of the injection cylinder.

With regard to the control of the intake valve 16 and the intake valves 53 in the pistons 14, 52 in both exemplary embodiments, it should also be noted that with the aid of an electromagnetic system in the cylinder hood 21, 80 and using a control device, the opening and closing of the intake valve 16 or the intake valves 53 can be controlled even more precisely with appropriately redesigned tension rods 25 or 60.

10 to 21 show a further exemplary embodiment of an engine operated with a homogeneous air / fuel mixture, for example gasoline, with a divided combustion chamber located in the center of the main combustion chamber HR, into which the fuel is injected directly.

The air-path profile from the upper cylinder space ZO to the main combustion chamber HR in the cylinder 13 is shown by arrows during the intake stroke.

10 shows in section A - A (section through the cylinder center, see FIG. 13) the crankcase 1, in which the crankshaft 2 with bearings and connecting rods 20, two camshafts 3 (for exhaust valves 10) with bearings, the injection nozzle 6, the spark plug 63, two rocker arm axles 8 and the seal 12 are installed. 10 corresponds to the intake stroke of the engine.

The crankcase 1 is closed from below, as in conventional engines, with an oil pan 9. At the upper part of the crankcase 1 there are connection grooves in which the cylinder 13 is centered. The area of the crankcase 1, which is delimited by the cylinder tube, serves as the cylinder bottom. In the middle of the cylinder base is the cylinder base recess, which has a raised collar. The injection nozzle 6 and the spark plug 63 are connected in the cylinder bottom recess. There are cooling channels (water space) under the cylinder bottom, which cool the entire upper area of the crankcase 1. On each side of the crankcase 1 there is a “window” through which access to the control members of the exhaust valve 10 (see FIG. 11) is possible. The “windows” are closed with covers 11.

The cylinder 13 is attached to the crankcase 1 either as a single tube with the water jacket cooling or as a cylinder block. The piston 14 is located in the cylinder 13 with a pneumatic damper 64 installed in the middle (see FIG. 15), which is connected to the intake valve package.

The cylinder hood 21 closes off the cylinder tube 13 from above and accommodates the large air inlet valve 22 and the large air outlet valve 23 with the associated springs 78. The cylinder hood 21 and the piston top form the cylinder upper space ZO. The piston underside (piston crown) and the cylinder crown form the main combustion chamber HR.

The camshaft 29 of the large air inlet valve is located on one side of the cylinder hood, and the camshaft 30 of the large air outlet valve is located on the other side. Each of the two camshafts 29, 30 is installed in a housing 31. The housings 31 are filled with lubricating oil and fastened to the intake pipe segment 32 or to the circulation pipe segment 33. The two pipe segments 32, 33 are laterally connected to the cylinder hood 21.

The cams 29, 30 control the large air valves 22, 23 via the flat slide 65, which are screwed into the middle of the valve in both large air valves 22, 23. At the same time, the large air valves 22, 23 are guided and centered by the slide 65. The sliders 65 have built-in rollers on the sides facing the camshafts 29, 30 which roll over the cams 29, 30 and which transmit the pressure of the valve springs to the cams 29, 30.

The suction pipe 34 is connected to the suction pipe segment 32, the circulation pipe 35 is connected to the circulation pipe segment 33.

Fig. 11 shows in section BB (see Fig. 13) the installation of the intake valve 53 and part of the intake ports in the piston 14 at the moment of the end of the combustion stroke. The section runs through inlet valves 53 and inlet channels in the piston 14, outlet valves 10, outlet channels and through one of two piston rods 67, 68 with sealing tion bushing package 66 and guide strips 4. In the crankcase 1, the installation of the exhaust valve 10 with control and exhaust channels, one of the two piston rods 67 (68) with a sealing bush 66, the guide strips 4 and the cross-head bolt 69 is shown. Each of the two piston rods 67, 68 is fastened in the piston 14, sealed in the cylinder bottom area with a sealing bush 66 and connected to the crankshaft 2 via the cross-head bolt 69 and the connecting rod 20 (see FIG. 10).

The head of each piston rod 67, 68 has two lateral slides which guide the piston rod 67, 68 between the guide strips 4. The carriages of the piston rod heads and the guide strips 4 transmit the side forces which arise from the gas pressure during the combustion cycle in the cylinder 13 and from the inertial forces during the movement of the engine components to the supporting structure of the crankcase 1.

The exhaust valve seats 36 are recessed in the cylinder bottom. Each exhaust valve 10 in the crankcase 1 is guided and sealed by the valve guide sleeve 37. The exhaust valves 10 are actuated by camshafts 3 through the rocker arms 38 and the valve tappet nuts 39 and are pulled back to the seats 36 with the valve springs 40.

At the connection of the cylinder 13 to the crankcase 1, connections between the cooling in the cylinder jacket and the cooling in the crankcase 1 are shown.

Fig. 12 shows in section A - A (see Fig. 13) the engine during the compression stroke at the moment of fuel injection. As an example, fuel jets - one upwards in the direction of the piston recess KM, a second in the direction of the spark plug 63 - are represented by "clouds". At the same time, air is drawn in from the intake manifold 34 through the piston 14 to the cylinder upper chamber ZO via the open large air inlet valve 22. The arrows show the course of the air movement. In FIG. 13, in section D - D (see FIG. 10), section through cylinder 13 and piston rods 67, 68, a view of the cylinder bottom with cylinder bottom recess ZM and exhaust valves 10 is shown. FIG. 13 shows four outlet valves 10, the cylinder bottom recess in the middle with the injection nozzle 6 and the spark plug 63, and two piston rods 67, 68 - piston rod 67 with a bore for the supply of lubricating oil and piston rod 68 with a bore for the suction of used lubricating oil.

FIG. 14 shows in section E-E (see FIG. 10) a top view of the piston 14, intake valve package and piston rods 67, 68. The piston 14 has two large depressions, each with two intake channels, into which the intake valves 53 are installed. The inlet valves 53 are guided by rounded springs of the piston and are connected to the pneumatic damper 64 via the cross-shaped valve holder 55. At the beginning of the intake stroke, the inlet valves 53 open (see FIG. 16) and the air is pumped over from the cylinder upper chamber ZO to the main combustion chamber HR via the inlet channels.

15 shows in section F - F (see FIG. 14) the piston 14 in its lowest position - bottom dead center - at which the compression stroke ends and the combustion stroke begins. The section runs through inlet valves 53 with guide, inlet channels in the piston 14, inlet valve holders 54, 55, pneumatic damper 64, outlet valves 10, outlet channels and closed combustion chamber KM, ZM. The compressed air in the main combustion chamber HR outside the closed combustion chamber (hollows KM, ZM) is shown by dark dots. In the meantime, the air-fuel mixture combustion stops in the closed combustion chamber KM, ZM (shown as points and clouds). The position of the fully open intake valves 53 and exhaust valves 10 is shown with dash-dotted lines.

15 also shows the complete assembly of the inlet valve package and the pneumatic damper 64. The inlet valves 53 are concluded. They are installed from the underside of the piston crown and are guided with a certain amount of play in the piston springs. Each valve is assigned a valve seat 76 which is pressed into the piston crown from below. At the top, all inlet valves 53 are connected to the cross-shaped valve holder 55 (also with a certain amount of play), which in turn is fastened on the pneumatic damper 64. The valve holder 55 consists of at least two identical, cross-shaped, flat springs which are centered on the shock bushing 70 and are screwed onto it with two nuts. The bolt of the pneumatic damper 64 is screwed into the shock bushing 70 and is secured against loosening with a nut. The bolt is guided in two bushings - upper 71 and lower 72. The upper bush 71 is installed in the screw bush 73, which in turn is screwed into the piston 14. The screw-in bushing 73 serves as a cover for the cylinder of the pneumatic damper 64 and as a stop for the shock bushing 70. Between the bushes (shock bushing 70 and screw-in bushing 73) there is a plate spring 74 which absorbs the shock of the inlet valve package which, when the Intake valves 53 arises, reduced. The plate spring 74 is fastened with a certain play by means of the screw-in ring 75 so that the screw-in ring 75 simultaneously secures the screw-in bushing 73 against loosening.

Fig. 16 shows in section A - A (see Fig. 13) the piston 14 in its lowest position - in the bottom dead center at the end of the extension stroke and the beginning of the intake stroke. The section runs through the cylinder center, piston 14 with pneumatic damper 64 and piston recess KM, cylinder base, cylinder base recess ZM with injection nozzle 6 and spark plug 63. The inlet valves 53 are fully open, the shock bushing 70 presses on the plate spring 74, and the pneumatic damper 64 has reached its lowest point. The exhaust valves 10 are not yet closed, which enables the main combustion chamber HR to be flushed. Arrows show the air movement taking place (the concealed inlet and outlet channels are shown with dashed lines). FIG. 17 shows in section AA (see FIG. 13) the combustion stroke of the engine (the piston moves upward in the direction of the arrow) at the moment when the two depressions KM, ZM divide and hot, burning, underneath Exhaust gases under pressure leave the closed combustion chamber KM, ZM. They spray through small grooves in the outer collar of the cylinder bottom trough ZM and through a gap between the trough collars into the main combustion chamber HR, where compressed air is located.

17 also shows the course of the channels of the piston lubrication system. Low pressure oil is pumped through the crankshaft 2, the connecting rod 20, the cross head pin 69 and the piston rod 67 to the piston 14 and further pumped through a small diameter channel in at least four points on the piston circumference to the groove of the lubricating ring 77. Oil thus fills the groove of the lubrication ring 77 and at the same time lubricates the inner surface of the cylinder tube during the piston movement.

The piston has two oil scraper rings 43. One oil scraper ring 43 is located above, the other below the lubrication ring 77. The oil scraper rings 43 collect the used oil from the inside of the cylinder tube in their grooves. The used oil is extracted from these grooves through the channels (at least four channels on the piston circumference), a large channel in the piston 14, the piston rod 68, the cross-head bolt 69, the connecting rod 20 and the crankshaft 2 through the suction pump. Small arrows in the channels show the oil flow in the piston 14.

18 shows a longitudinal section G - G (see FIG. 14) through the cylinder hood 21 and the piston 14 with a pneumatic damper 64, two piston rods 67, 68 and piston recess KM. In the cylinder cover 21, the large air outlet valve 23 is installed, which is guided and opened by the slide 65 and then pushed back to its seat by two springs 78. Both piston rods 67 and 68 are fastened in the piston 14. The piston 14 is in its highest position. The large air inlet valve 22 is constructed identically to the large air outlet valve 23 and is a mirror image of the cut surface on the other side of the cylinder 13.

FIG. 19 shows the broken-out section through the piston rod 67 and the sealing bush 66, the package of the sealing bush 66 in the vicinity of the exhaust valves 10. The seal bushing packages enable the sealing of the piston rods 67, 68 at the transition through the cylinder base, even if the distance between the two piston rods 67, 68 firmly anchored in the piston changes due to thermal expansion of the piston 14. The seal bushing package consists of the screw-in bushing 79, the sealing bushing 66, the screw-in pressure bushing 80 and the disk spring assembly 81.

The screw-in bush 79 has a bore at the top, the diameter of which is approximately twice the thermal expansion between the piston rods than the diameter of the piston rod 17. Below this bore of the screw-in bush 79, inside the screw-in bush 79, there is a small, highly polished surface which the highly polished face of the sealing bush 66 is pressed by the plate spring assembly 81. The plate spring assembly 81 is tensioned by the screw-in pressure bushing 80. Because the inner diameter of the screw-in bushing 79 is larger than the diameter of the sealing bushing 66, the sealing bushing also shifts when the piston rod 17 is displaced. Despite this shift, the seal between the main combustion chamber HR and crank chamber remains. The sealing bush also serves as an oil wiper bush.

20 shows the section K - K (see FIG. 11) through the cross-head bolt 69, the connecting rod head 20, the heads with slides of the piston rods 67; 68 with the associated bearings and the course and the connection between the channels for the oil supply and oil extraction, which are located in the components mentioned. In addition, the exhaust valves 10 with the valve guide sleeves 37 are the crankcase 1 Lassventile 10 with the valve guide sleeves 37, the crankcase 1 and the guide strips 4 shown.

Finally, in section A - A (see FIG. 13), FIG. 21 shows an exemplary embodiment in which the piston recess KM and the cylinder base recess ZM are designed as inserts 82 and 83, respectively. In this embodiment, the trough inserts 82, 83 can be made from building materials other than those that are used in the piston 14 or crankcase 1.

The mode of operation of the engine shown in FIGS. 10 to 21 is shown below, the engine being operated in a 4-stroke process with a homogeneous air / fuel mixture.

During the extension stroke, the two piston rods 67; 68 the piston 14 downwards and the piston 14 pushes the exhaust gases out of the main combustion chamber HR (between the underside of the piston and the cylinder bottom) through the opened exhaust valves 10 to the exhaust ports.

The exhaust gases have a much lower resistance than in conventional engines, because four exhaust valves 10 together result in a large exhaust cross-section and, in addition, short exhaust gas paths facilitate the extension.

At the same time, the upper side of the piston sucks the air from the suction pipe 34 through the opened large air inlet valve 22 to the cylinder upper chamber ZO (between the cylinder hood 21 and the upper side of the piston) during the piston movement downward. The large air outlet valve 23 remains closed. When the piston 14 comes close to the bottom dead center and significantly reduces its speed, the inlet valves 53 which are not fixedly connected to the piston 14 move further down together with the pneumatic damper 64 due to the effect of inertia. At the beginning, the pneumatic damper 64 throttles the movement of the intake valves 53 down until the The collar of the damper 64 leaves the upper fitting bore in the damper cylinder and moves to a wider position in the damper cylinder.

Then there is a rapid movement of the inlet valves 53 downwards, until shortly before the bottom dead center of the piston the collar of the damper 64 reaches the lower fitting bore in the damper cylinder. The further movement speed of the inlet valves is then clearly dampened again down to their lowest position, at which the shock bushing 70 reaches the plate spring 74.

At this moment, when the pneumatic damper 64 reaches its lowest point, the intake valves 53 are fully opened. Air flowing out of the intake manifold 34 is compressed in the cylinder upper chamber ZO due to a rapid decrease in the speed of the piston movement (dynamic supercharging effect). A part of this air flows further through the already opened inlet valves to the main combustion chamber HR, flushes this space from residual exhaust gases and flows further through the still open outlet valves 10 to the outlet channels (see FIG. 16). The exhaust stroke ends here and the suction stroke begins.

The piston rods 67, 68 press against the piston 14, whereupon the piston 14 begins to move upward from bottom dead center. The exhaust valves 10 close. During the movement of the piston 14 upward, the large air inlet valve 22 closes. In spite of the fully open inlet valves 53 in the piston, the air in the cylinder upper chamber ZO is compressed and at the same time the air pressure drops under the piston 14 moving upward in the main combustion chamber HR. The air flows from the upper cylinder area ZO via the intake valves to the main combustion chamber HR. The first portion of air (first layer) remains on the cylinder bottom and heats up on the hot surfaces of the exhaust valves 10 and the trough walls. This air layer has turbulence that was caused in the flow through the inlet valves 53 when the piston moved upward. After separating the combustion chamber troughs KM, ZM, this turbulent air flushes the two separate troughs KM, ZM from residual exhaust gases. The smaller amount of exhaust gas from the combustion chamber KM, ZM mixes with the fresh air that has just come out of the intake valves. If there is a large excess of air, the small amount of exhaust gas does not have a negative impact on the further course of combustion, but on the contrary acts as a means of reducing nitrogen emissions.

The additional air that flows into the main combustion chamber HR remains for a short moment under the piston head of the upwardly moving piston 14 due to a suction effect. This air has much stronger turbulence, which is caused by a higher piston speed than at the beginning of the intake stroke is present. It is then replaced by inflowing air layers. At the end of the intake stroke, the piston speed drops and is zero at top dead center. The significant reduction in the piston speed shortly before the top dead center causes the inlet valve package which is not firmly connected to the piston 14 to move further upward due to inertia.

At the beginning, this movement is throttled by the action of the pneumatic damper 64 until the collar of the damper 64 leaves the lower fitting bore in the damper cylinder and moves to a wider position in the damper cylinder. Then there is a rapid movement of the intake valve package until the collar of the damper reaches the upper fitting hole in the damper cylinder and throttles the movement of the intake valve package again until the intake valves reach their seats. The pneumatic damper 64 moves upward due to inertia and tensions the cross-shaped valve holders 55. The intake valves are closed, at this moment the intake stroke ends and the compression stroke begins. The large air intake valve 22 in the cylinder hood 21 opens while the intake valve is closing in the piston 14. The piston rods 67, 68 now pull the piston 14 downward. The inlet valves 53 and the pneumatic damper 64 are still under the influence of inertia due to the turning of the piston movement, the inlet valves 53 are pressed against their seats 76. The rapidly increasing pressure in the main combustion chamber HR increases this pressure on the inlet valves 53. The piston 14 moving downward compresses the air in the main combustion chamber HR. At the same time, air flows from the intake manifold 34 into the upper cylinder space ZO, which is drawn in by the piston 14 moving downward.

The engine control in partial load operation is described below.

When the piston 14 reaches approximately a quarter of the distance from the bottom dead center, the injection nozzle 6 injects the fuel jets into the two depressions KM, ZM. The fuel jet sprayed in the direction of the piston bowl KM moves in compressed air, strikes one side of the piston bowl KM (see FIG. 12) and causes a spherical swirl of the air / fuel mixture on the inclined surface of the bowl KM.

The second smaller fuel jet is sprayed towards the spark plug 63 at an incline into the trough bottom ZM. This fuel jet also causes a spherical swirl of air-fuel mixture, but which has a different direction of rotation than that in the piston bowl KM. The piston recess KM has a lower temperature (because of longer contact with flowing fresh air during the intake stroke) than the cylinder base recess ZM, which is located between the four exhaust valves 10. Despite the low temperature, the fuel injected into the KM piston bowl has sufficient time to evaporate due to a small amount of fuel, a long way to the KM bowl and an intense swirl. The piston 14 continues to move downward. The collar of the KM piston recess comes into contact with the outer collar of the ZM cylinder base recess. From this moment on, the two troughs KM, ZM form a closed combustion chamber KM, ZM, which closes off the air-fuel vapor mixtures from both troughs KM, ZM. The piston bowl collar plunges into the cylinder bowl bowl with very little play. In the closed combustion chamber KM, ZM, the compression ratio of the air / fuel vapor mixture grows faster than the compression ratio of the air outside the combustion chamber in the main combustion chamber HR due to the volume loss due to the immersion of the piston recess. The pressure loss in the combustion chamber KM, ZM is low due to the small play between the two coils.

At this time, the large air intake valve 22 closes and the large air exhaust valve 23 opens. Shortly before the bottom dead center of the piston 14, the spark plug 63 ignites the air / fuel vapor mixture and after a short delay in ignition, the flame spreads throughout the combustion chamber KM, ZM.

With further movement downward, the piston 14 reaches its bottom dead center and the combustion chamber KM, ZM reaches its smallest volume. From this moment the compression cycle ends and the combustion cycle begins. The combustion stops in the closed combustion chamber KM, ZM, and the pressure increases rapidly due to the release of heat. Because of the favorable placement of the spark plug 63 in the warmest part of the combustion chamber KM, ZM, namely in the cylinder bottom bowl ZM, because of the small volume of the spherical combustion chamber KM, ZM and because of the colder walls of the opposite piston bowl KM, there is no knocking despite the largest possible compression ratio Combustion.

The piston 14 now moves upwards. Shortly before the combustion chamber troughs KM, ZM are separated, burning hot gases contained therein spray through a small gap between the inner collar of the piston troughs. de KM and the outer collar of the cylinder bottom recess ZM, as well as through small recesses in the outer collar of the cylinder bottom recess ZM, targeted upwards and downwards into the main combustion chamber HR to pressurized colder but denser air. The aforementioned specializations are in the area of the federal introductory phase, see Fig. 17.

The air in the main combustion chamber HR expands quickly. The combustion of fuel vapors and other combustible gases not burned in the closed combustion chamber KM, ZM, e.g. CO, which has now reached oxygen, continues and after-reactions take place. The pressure in the main combustion chamber HR is growing rapidly. Now the piston 14 pulls the piston rods 67, 68 upwards. The pulling force is transmitted from the piston rods 67, 68 to the connecting rod 20, where it is converted into the torque of the engine. The piston 14 moving upward forces the air out of the cylinder upper chamber ZO through the large air outlet valve 23 into the circulation pipe 35. This expelled air goes partly into the intake pipe 34, partly into the exhaust pipe. The decision in turn depends on the air temperature (control with a thermostat) and the load state of the engine (control with a control system).

Shortly before the top dead center of the piston 14, the large air outlet valve 23 closes and the large air inlet valve 22 opens.

When the piston 14 reaches top dead center, the combustion stroke ends and the exhaust stroke begins. From this moment on, part-load operation follows in the 4-stroke process.

In part-load operation, fuel is injected into the troughs KM, ZM in appropriate quantities, depending on the need for engine power. The injection quantity is calculated so that in the closed combustion chamber KM, ZM the homogeneous mixture is in the range from λ = 0.8 to λ = 1.2 (depending on the specified engine load), which means "clean" combustion in the combustion chamber KM, ZM results The course of the combustion takes place at the moment of the combustion chamber separation, when the still burning gases are "injected" into the compressed air around the combustion chamber into the main combustion chamber HR and further after-reactions are caused. The two-stage combustion combination releases extremely low-emission gases and it becomes one optimal air utilization with very low power losses when changing loads (inflow and outflow).

The engine control in full load operation is described below.

When the engine load increases, the power that the central combustion chamber, consisting of the two troughs KM, ZM, produces is insufficient, despite the use of a "rich" air / fuel mixture with a λ value of 0.8 In addition, fuel is additionally injected into the cylinder 13, specifically into the main combustion chamber HR.

Immediately after separation of the combustion chamber KM, ZM at the beginning of the intake stroke, fuel is injected from the injection nozzle 6 into the two depressions KM, ZM. Air flows into these troughs from the inlet valves, which has great turbulence, and which flushes the troughs free of residual exhaust gases. At the same time, it takes extremely fine droplets of fuel with it, which evaporate quickly in good thermal conditions (warm trough walls and air warmed by the exhaust valves) and form an air-fuel vapor mixture.

This mixture remains in the lowermost warm air layers near the cylinder floor recess, because it is compressed by the air layers arriving from the intake valves. The piston continues to move upwards and only clean, cool and dense air enters the upper parts of the main combustion chamber HR.

In the vicinity of the top dead center of the piston 14, the intake valves 53 close and the compression stroke begins. The same procedure Repeat as in part-load operation, only with the difference that outside the closed combustion chamber KM, ZM there is no pure air as in part-load operation, but two gas layers: a warmer one made of air-fuel vapor mixture that remains on the cylinder bottom and a second one out almost pure air, which remains on the colder piston crown and the intake valves and which isolates the first layer from heat loss.

The combustion cycle after the combustion chamber separation has a different course than in part-load operation. Hot, burning gases spurt out of the separate combustion chambers (depressions) and cause combustion of the air-fuel vapor mixture, which is concentrated in the cylinder bottom area. The pressure in the main combustion chamber HR then increases much more than in part-load operation and is converted into a significantly higher torque of the engine. Because of the large excess of air in the main combustion chamber HR, the combustion runs optimally, there are also after-reactions and a significant reduction in the temperature of the exhaust gases at the end of the combustion cycle. As a result, the exhaust gases are pushed out of the main combustion chamber HR with as little pollution as in part-load operation.

In both cases - in part-load and full-load operation - the amount of air pumped over to the main combustion chamber HR is almost the same. A small difference between the quantities of air pumped over to the main combustion chamber HR is caused by different air speeds in the intake manifold during the intake, because the dynamic charge is dependent on this air speed.

In this engine design, there are no throttling elements as control elements, the air is drawn into the cylinder upper chamber ZO unthrottled and is only over-pumped into the main combustion chamber HR during the intake stroke. The engine is only controlled by the amount of fuel injected in various load conditions. In partial load operation, the injection takes place only once in the closing troughs, in full load operation twice (or several times): the first time at the start of the intake stroke in the separating troughs KM, ZM, the second time at the end of the compression stroke in the closing troughs KM , ZM.

LIST OF REFERENCE NUMBERS

crankcase

crankshaft

camshaft

guide rail

guide bush

injection

Glow plug

rocker shaft

oil pan

outlet valve

cover

poetry

cylinder

piston

cross use

Intake valve actuator

piston rod

threaded pin

Phillips

pleuel

cylinder cowl

Air inlet valve

Air outlet valve

Kolbenhubbegrenzerhülse

tension rod

Einschraubführungsbuchse

stop nut

bolt

Cam or camshaft of the air intake valve 48

0 Cam or camshaft of the air outlet valve 1 housing 2 intake manifold segment 3 air recirculation tube segment 4 intake manifold

35 air circulation pipe

36 Valve seat outlet

37 valve guide sleeve

38 rocker arm

39 valve lifter nut

40 valve spring

41 injection pistons

42 suction pistons

43 Oil scraper ring

44 piston sealing ring

45 oil atomizers

46 screw-in insert

47 screw-in insert

48 disc

49 injection cylinders

50 cylinder hood

51 injection pistons

52 pistons

53 inlet valve

54 Lower intake valve holder

55 Upper inlet valve holder

56 centering bolts

57 threaded pin

58 valve seat

59 spacer sleeve

60 tension rod

61 suction pistons pen

spark plug

Pneumatic damper

pusher

sealing bush

Piston rod - oil supply

Piston rod - oil suction

Phillips bolts

impact socket

Socket - top

Socket - below

screw bushing

Belleville spring

screw ring

Inlet valve seat

lubricating ring

feather

screw bushing

Einschraubdruckbuchse

Belleville spring assembly

Piston recess - insert

Cylinder floor recess - insert

Claims

claims

1. Combustion 4-stroke piston engine, the engine comprising cylinder (13), piston (14) and crankcase (1), characterized in that the cylinder space through the piston (14) in a cylinder head-side cylinder space (ZO) and in a crankcase side

Combustion chamber (HR) is divided, the piston (14) comprising at least one inlet valve (16, 53) for gas transfer between the cylinder upper chamber (ZO) and the combustion chamber (HR), and the combustion chamber (HR) being delimited by the piston crown, cylinder wall and cylinder crown and has at least one exhaust valve (10) in the region of the cylinder base.

2. Internal combustion engine according to claim 1, characterized in that the piston (14) by means of a crosshead (19) and at least one piston rod (17, 67, 68) is connected to a connecting rod (20) of the engine, the cylinder bottom being separated from the piston rod ( 17, 67, 68) is permeated.

3. Internal combustion engine according to claim 1 or 2, characterized in that at least one air inlet valve (22) for fresh air intake is arranged in the cylinder upper chamber (ZO).

4. Internal combustion engine according to one of claims 1 to 3, characterized in that in the cylinder upper chamber (ZO) at least one air outlet valve (23) for emptying the cylinder upper chamber (ZO) is arranged.

5. Internal combustion engine according to claim 3 and 4, characterized by an air circulation pipe (35) for charging the intake air, the air circulation pipe (35) forming a connection between the air outlet valve (23) and the air inlet valve (22).

6. Internal combustion engine according to claim 5, characterized in that the air circulation pipe (35) has a connection to an exhaust pipe.

7. Internal combustion engine according to claim 5 or 6, characterized in that the connection has a controllably variable opening.

8. Internal combustion engine according to one of claims 1 to 7, characterized in that the control of the inlet valve arranged in the piston (16,

53) is set up in such a way that the inlet valve (16, 53) is opened during the intake stroke for the purpose of overflowing the fresh charge from the cylinder chamber (ZO) into the main combustion chamber (HR).

9. Internal combustion engine according to one of claims 1 to 8, characterized in that the opening and / or closing movement of the inlet valve takes place at least in part due to inertial forces in the region of the piston turn.

10. Internal combustion engine according to one of claims 1 to 9, characterized in that the valve control of the engine is set up in such a way that two fresh charge intake into the cylinder (13) takes place during the four cycles of an engine cycle.

11. Internal combustion engine according to claim 10, characterized in that the valve control of the engine is set up in such a way that the first fresh charge suction when the inlet valve (16, 53) and the outlet valve (10) is open flushes the combustion chamber (HR) and the second fresh charge suction when the inlet valve is open (16, 53) and closed exhaust valve (10) which supplies combustion air.

12. Internal combustion engine according to one of claims 1 to 11, characterized in that the combustion chamber in the main combustion chamber (HR) and at least one

Burning tray is divided.

13. Internal combustion engine according to one of claims 1 to 1 1, characterized in that the combustion chamber is divided into the main combustion chamber (HR) and separate combustion chamber (KM, ZM), the combustion chamber (KM, ZM) spatially in the main combustion chamber (HR) included and is formed from the cylinder bottom recess (ZM) and piston recess (KM).

4. Internal combustion engine according to claim 13, characterized in that the cylinder bottom recess (ZM) and piston recess (KM) each have a raised collar, the outer circumferential shape and size or outer diameter of one of the recesses of the inner circumferential shape and size or the inner diameter of the other Corresponding bowl collars, so that when the bowl collars engage each other, a closed combustion chamber is formed from the two bowls.

15. Internal combustion engine according to claim 13 or 14, characterized in that the cylinder bottom recess (ZM) is larger than the piston recess (KM).

16. Internal combustion engine according to one of claims 13 to 15, characterized in that the internal combustion engine per piston (14) has two piston rods (67, 68), the cylinder bottom recess (ZM) between the piston rods in the middle of the cylinder bottom and the piston recess (KM ) is also arranged between the piston rods (67, 68) in the middle of the piston crown.

17. Internal combustion engine according to one of claims 12 to 16, characterized in that at least one injection nozzle (6) and at least one spark plug (63) or glow plug (7) are connected to the combustion bowl or combustion chamber (KM, ZM).

8. Internal combustion engine according to claim 13 and 17, characterized in that the injection nozzle (6) and spark plug (63) or glow plug (7) in the region of the cylinder bottom recess (ZM) are connected to the combustion chamber (KM, ZM).