WO2013037366A2

WO2013037366A2 - Internal combustion engine with a high degree of efficiency

Info

Publication number: WO2013037366A2
Application number: PCT/DE2012/100281
Authority: WO
Inventors: Arno Mecklenburg
Original assignee: Arno Mecklenburg
Priority date: 2011-09-14
Filing date: 2012-09-14
Publication date: 2013-03-21
Also published as: WO2013037366A3; EP2756181A2; DE112012003832A5

Abstract

A reciprocating piston engine is described. According to one aspect of the present invention, the reciprocating piston engine comprises at least one cylinder and a piston which is guided therein and a system for fuel injection, wherein the engine operates entirely or predominantly as a compression-ignition engine, and wherein the system for fuel injection is configured in such a way that, in every work cycle, a large part of the fuel which is to be injected in the work cycle into the cylinder is injected in a time period which is smaller than or equal to the respective ignition delay time. According to the invention, a large part of the fuel is therefore injected before the compression ignition takes place.

Description

High efficiency combustion engine

Technical Field: The invention relates generally to the field of reciprocating engines, such as e.g. Diesel engines.

Background of the Invention: Gasoline and diesel engines are generally in the most diverse

Embodiments known. A fundamental weakness of known piston engines is that the crankshaft has a particularly unfavorable lever ratio near top dead center (TDC). This is precisely where the highest compression is achieved in the combustion chamber, ie where the hot working gas could do the most effective work. The most favorable leverage arises only with a rotation of the crankshaft about 60 °, namely, when the connecting rod is perpendicular to the crank arm. A consequence of the mentioned unfavorable lever ratio are additional

Heat losses that reduce the efficiency of the reciprocating engine. The high combustion chamber pressure can lead to a certain blow-by, which is still promoted by the low velocity of the pistons in the vicinity of the TDC and possibly by the transverse forces acting on the piston.

An elegant but at the same time disadvantageous one

Arrangement to remedy this weakness has described the Australian company Revetec Inc. in the publication WO 2008/028252 A1. In the engine described there, the crankshaft was replaced by two counter-rotating cams on which rolling bearings roll, which in turn at the

Piston rod are attached. At each end of a piston rod there is a piston which works into its own cylinder. At the same height below each piston are two rolling bearings on the piston rod attached. Between the four rolling bearings (two for each piston) are finally clamped the two counter-rotating cams. By designing the cams (each with at least three cam lobes), the most favorable leverage closer to top dead center (TDC) can be achieved.

Accordingly, it is not surprising that prototypes of the Revetec engine designed as an Otto engine should have a particularly high level of efficiency for gasoline engines. It is known that the efficiency of gasoline engines because of the lower compression is lower than that of diesel engines, and that although the constant combustion (ie the gasoline process) - with the same compression - significantly more efficient heat engines allows than the constant pressure combustion (ie the diesel process ). However, there is no ideal Otto process in the gasoline engine, in particular because the combustion is by no means isochronous due to the low laminar flame velocities of ordinary gasoline fuels. There is no ideal diesel process in the diesel, because the combustion is not isobaric - the ignition delay even leads to very fast initials

Combustion at auto-ignition ("nailing"), which is actually almost isochoric.

Given the above-described deficiencies of known engine concepts, the object underlying the invention in the creation of a

Reciprocating engine with improved efficiency. Summary of the invention:

The above object is achieved by an engine constructed according to one of the independent claims. It becomes a reciprocating engine

described. According to one aspect of the present invention, the reciprocating engine comprises at least one cylinder and a piston guided therein and a system for fuel injection, wherein the engine is fully or predominantly works as a diesel engine and wherein the system for fuel injection is designed such that in each power stroke, a large part of the fuel injected into the cylinder during the working cycle in a period of time is less than or equal to the respective

Ignition delay time is. According to the invention, therefore, a large part of the fuel is injected before the autoignition takes place.

An example of the invention relates to a reciprocating engine having at least one cylinder and at least one guided in the cylinder piston, the between a top dead center (TDC) and a bottom dead center (UT) a

periodic lifting / lowering movement performs. In contrast to conventional diesel or gasoline engines, a transmission is provided for converting the lifting / lowering movement (dh / dt) of the at least one piston into a rotational movement (dOmega / dt), wherein the transmission is an angle-dependent

Gear ratio (dOmega / dh) has. The engine further includes a system for fuel injection, wherein the system for

Fuel injection is set so that in each working stroke of the piston, the majority of the fuel is injected in a period which is less than or equal to the respective Zündverzugszeit. The transmission is designed such that immediately after reaching top dead center, the transmission ratio (dOmega / dh) is lower and / or a minimum transmission ratio (dOmega / dh) is reached earlier than when using a conventional crankshaft. In particular, the system for fuel injection can be set such that autoignition takes place after top dead center has been reached, and that the pressure in the cylinder is maximum at a point in time at which the

Gear has the shortest gear ratio (dOmega / dh). A maximum expansion speed can then be close to the maximum

Combustion chamber pressure can be achieved. According to one embodiment, the engine is designed as an opposed piston engine, in which two associated pistons are guided in each cylinder. The engine can be designed as a two-stroke engine. In the two-stroke piston engine, a charge exchange can be effected by the two pistons release inlet and outlet ports in the cylinder, wherein the transmission is designed such that mutually associated piston their upper

Totals and thus reach a maximum compression almost simultaneously, offset their bottom dead centers on the other hand. A piston releases the outlet channel or the outlet channels first and then closes them again before the other piston assigned to it opens the inlet channel or the inlet channels.

This avoids flushing losses and thus allows charging, higher efficiency and better emissions, especially with regard to unburned hydrocarbons.

Brief description of the figures:

The invention will be explained in more detail below with reference to the examples shown in the accompanying figures. The representations are not to be construed as limiting and are not true to scale, rather value is placed to illustrate the underlying principle of the invention. In the figures: FIG. 1 shows an illustration of the transmission ratio between the

Stroke movement of a piston and the rotational movement of a crankshaft in a conventional engine, and a sectional view through an exemplary

Opposite piston engine according to the present invention In the figures, like reference characters designate like or similar parts of same or similar meaning

Detailed description of the invention:

An idea underlying the invention is to run to increase the efficiency of an optimal Otto process at a high, typical of diesel engines compression by the im

original diesel engine is exploited unwanted ignition delay. "Ignition delay" is generally understood to mean the period from the beginning of the

Fuel injection into the cylinder of an engine until the actual start of combustion of the air-fuel mixture. Especially in diesel engines, the ignition delay is known as a speed limiting feature, as the

Combustion does not begin immediately with the injection. The ignition delay can be influenced by various factors, including the

"Ignitability" of the fuel, which is described by the cetane number, the temperature and the pressure in the combustion chamber and of the

the type of mixture formation, which can be influenced for example by the nozzle shape of the injector and the air duct.

The idea is therefore to first modify a conventional diesel engine so that the fuel is injected and atomized as completely as possible and mixed with air before the combustion starts spontaneously. For this purpose, the engine can be controlled accordingly, the open hole cross-section of the injection nozzle increases and / or increases the injection pressure and / or the

Number of injectors per combustion chamber (in relation to conventional 4-stroke diesel engines) are increased. For this purpose, particularly highly dynamic, in particular piezo-driven injectors can be used. The result of this modification is a "deliberate" strong nailing, which comes very close to an ideal equal-space combustion and which is associated with an abrupt increase in the pressure in the cylinder. Although this combustion process is thermodynamically very favorable, but in engines with crank mechanism for the following reasons only in low

In conventional engines (such as used in motor vehicles) with crank mechanism, the cylinder pressure generated immediately after TDC barely usable torque, but the force acting on the piston must be mainly absorbed by the connecting rod, crankshaft, crankcase and the associated bearings and loaded this strong. A rotation of the crankshaft by an angle omega (where omega (OT) = 0 °) leads at usual connecting rod lengths only at about omega = 60 ° to the shortest, so cheapest, translation dOmega / ie between the linear movement h of the piston and the rotational movement omega of the crankshaft. In this

Angular position but the working gas has already expanded significantly, so the maximum torque can be reduced accordingly. Due to the compared with engines according to the invention, long residence times of the hot and high pressure working gas at piston positions near OT would be (in quasi-isochoric combustion in medium and high load ranges) additional heat losses and possibly a high blow-by. Thus, the benefits of equal volume combustion disappear in conventional reciprocating engines, at least in higher load ranges, and do not justify the extreme mechanical stress of a type of combustion as described above (the "intentional heavy nailing").

This problem is solved by the invention described herein

Embodiments solved in that instead of a conventional crank mechanism (or in addition to such) another device for the translation of the linear piston movement is used in a rotary motion, which is characterized in that they are a cheaper (ie short)

Gear ratio dOmega / dh between piston movement dh / dt and wave motion dOmega / dt as quickly as possible (time, time t) or close

(spatial, angle omega) after reaching the maximum Has Verdichtungsverhätnis than is possible in conventional crank drives same stroke in conventional diesel or gasoline engines. The faster expansion of the hot working gas (in the immediate vicinity of the maximum temperature T _M AX) compared to engines with conventional crank mechanism leads to a particularly high maximum torque and also reduces heat losses through the cylinder wall. The unfavorable in conventional crank gears transmission ratio is shown in Fig. 1.

In summary, an engine constructed in accordance with the embodiments described herein may be operated as a "self-igniter" which

(Total) achieves a (total) compression ratio which is higher than in conventional gasoline engines, and which is further characterized in that the largest possible part of each injection quantity is injected in a period of time which is less than or equal to the respective ignition delay time , The Zündverzugszeit is given primarily by the fuel used (cetane number) and by pressure and temperature in the combustion chamber. That is, ignition delay time is essentially a function of fuel type, compression, and charge air temperature and humidity. In addition, the working piston according to the invention engines via drives

driven, unlike conventional crank mechanisms as soon as possible

Achieve OT as favorable as possible (ie short) ratio have (so that a lowering of the piston by one way, ie the smallest possible angle of rotation dOmega result) in order to make optimal use of the inventively abruptly building very high cylinder pressure.

Such a built-up engine achieves high efficiency and high maximum torque, and in two-stroke opposed piston construction, moreover, its high power density and high midrange

Torque. Furthermore, a simple structure is possible and it can

Transverse forces and / or torques on the working piston can be avoided. Good lubrication (separate lubrication) can also be achieved in two-stroke Counter piston design without valves are guaranteed, with a

Mixing of lubricant and charge air is avoided.

The following is an example of a possible embodiment of a

Motor according to the invention described. The embodiment is not to be construed as limiting, rather value is placed on the

To illustrate the invention underlying principles.

According to an exemplary embodiment of the invention, the engine is constructed as a supercharged "valveless" two-stroke opposed piston engine with a plurality of injectors disposed about the circumference of the combustion chamber. "Half", see Figure 2) Rhomben gearbox driven, so a rhombic gear per piston, which rotate in the same direction, but work in opposite directions. The rotation of the transmission is synchronized in such a way that both working pistons reach their TDC as simultaneously as possible. Now, designs and equations of motion of rhombic transmissions are well known and can be readily configured by the skilled person according to the invention. For example, one of the

Rhombic gears are designed so that the associated

Working piston (hereinafter "piston 1") approximately following

Equation of motion suffices:

Stroke (piston 1, omega) = A ^* (- (cos (omega)) + sqr (4- (1 -sin (omega)) ^A 2)) + offseti

This can be achieved, for example, by the distance of the connecting rod bearing on the piston 1 from the cylinder axis is equal to the minimum distance of the associated crank pin of the same cylinder axis. If the crank pins are exactly "inside", ie are closest to one another, the associated connecting rod bearings on piston 1 are located exactly "above" the respective crank pin along the cylinder axis. If then the effective length of the connecting rod is chosen so that they even the double eccentricity of the crankpin corresponds, the results

above equation of motion. The co-rotating but opposite working rhombic transmission of piston 2 then performs a movement:

Stroke (piston 2, omega) = A ^* (- (cos (-Omega + pi)) + sqr (4- (1-sin (-Omega + pi)) ^A 2)) + Offset2

Thus, both pistons satisfy the above-mentioned requirement, as far as possible immediately after reaching the TDC a much cheaper

Own gear ratio as a conventional crank mechanism whose movement near OT in a wider range is approximately harmonious. However, the above functions are not symmetrical to yours

Extreme values. If the rhombic gears operating in the same direction but synchronously working opposite are now synchronized with respect to the top dead centers (OTs) of their pistons, the associated bottom dead centers (UTs) are reached offset. This provides the opportunity to charge the valveless two-stroke engine. First, the outlet piston (the one with the shorter ratio after reaching TDC) reaches exhaust ports. The burned mixture is blown out. Then, the exhaust piston reaches its BDC, reverses to close the exhaust ports. Only then does the

Intake piston the intake ports and the cylinder can be filled and even charged (high).

The (additional) charging of the engine with the charging piston can be high

Exhaust gas energies result, which of course, even by known methods, can and should be used. For the use of the engine in modern hybrid vehicles or as "ranks extender" in electric vehicles or even in "diesel-electric" drives the following solution is special suitable: The exhaust gas drives a possibly multi-stage turbine, which drives both a compressor, for example, a centrifugal compressor, as well as an electric generator. Alternatively, a turbocharger with an additional power turbine could be used. It can be between the

Intake of the engine and the compressor in a known manner

Intercooler be arranged. A chemical agent (for example urea solution) for exhaust aftertreatment can be injected into the exhaust gas before entering the exhaust gas turbine (SNCR). The generator

Provided electrical energy can be used to operate on-board electrical systems or for propulsion purposes. For the fastest possible achievement of high engine power but also the generator can be used as a short time

Electric motor used and in turn drive the turbocharger.

The operation of a motor according to the invention will now be explained by means of a further embodiment based on an engine concept used in the Junkers JUMO 205 motor, since this motor is well known on the one hand and, on the other hand, as the closest prior art. The JUMO 205 was a diesel engine (aircraft engine) in two-stroke counter-piston construction. Rinse losses he avoided by means of a transitional difference between the crank gears. Imagine a JUMO 205 first, but as a 4-cylinder in-line engine (instead of six cylinders). Furthermore, each cylinder is equipped with its own turbocharger, which is to work in shock, so with the least possible line volume and resistance between the cylinder and turbocharger exhaust gas turbine (i.e., impact turbine). The exiting from the thrusters exhaust gases are collected in a thermally insulated pitot tube and fed to a common turbine (accumulation turbine), which

For example, via a reduction mechanically coupled to the drive shafts of the piston engine or drives an electric generator. The supercharged by the turbochargers charge air is in a common

Charge air cooler led before it is passed into the cylinder. To get from this engine concept to an embodiment of the invention, additional changes must be made, as described below.

The crank mechanisms must be replaced by transmissions which as short as possible (time t) or near (crank angle omega) after reaching the maximum compression ratio (ie after completion of the compression stroke) the highest possible expansion speed, ie the highest possible dV / dt, where V = combustion chamber volume. (This corresponds to one

as short lever ratio dOmega / ie, in contrast to the kinematics of conventional crank mechanisms, which in the vicinity of the reversal points particularly long Hebelverhätnisse - and thus have a long residence time-). A maximum expansion speed should continue to be achieved as simultaneously as possible with the maximum combustion chamber pressure. Concerning the combustion process, it should be noted that a particularly fast combustion process should be chosen, which comes as close as possible to an isochoric heat supply.

In the present exemplary embodiment, the combustion method according to the invention is represented as follows: A multiplicity of fast injectors, for example piezo injectors, are respectively arranged around the cylinder peripheries. The fuel is thus injected with a radial (with respect to the cylinder) component, which may result in a comparatively long sputtering distance, which allows for the same injection pressure higher nozzle cross sections. In addition, since a plurality of injectors is injected into each combustion chamber, a particularly high injection volume flow can be achieved with the aid of this arrangement. Ideally, the entire injection quantity is injected and atomized within the ignition delay time. Unless until

Autoignition sufficient mixture formation takes place, can be largely excluded by the absence of a diffusion flame soot formation. The combustion process is thus similar to a HCCI (HCCI = Homogeneous Charge Compression Ignition) or PCCI procedure

(PCCI = Premixed Charge Compression Ignition), where - unlike

conventional HCCI or PCCI engines - the changed kinematics of the piston drive (and possibly also the absence of valves) the operation with high heat rates (and thus high pressure gradients) even in higher

Load ranges.

In order to reduce the injection amount required for the main injection, a part of the fuel may already be added to the charge air, for example, with a pilot injection or a port injection; the

Fuel quantity would be as possible to be dimensioned so that the premix alone is not ignitable under engine conditions or has a very large ignition delay. As described above, in order to carry out the invention, the crank mechanisms of the JUMO 205 must be replaced by an output according to the invention. This is shown in FIG. For this purpose, each crankshaft of the JUMO 205 could be replaced by two adjacent crankshafts (with rotation axis 10 and crankpin 20), each piston 40 being connected to both crankshafts via two connecting rods 30. Such constructions are also known as (half) rhombic gears (e.g., Stirling engines); There, they serve mainly to avoid lateral forces (piston rod guided piston) and are also characterized by an excellent

Mass balance to have. It is possible a balance of all rotating mass forces, in addition, the balance of all oscillating

Forces of first order already possible with one piston.

Characteristic of Rhombengetriebe is (in addition to the rapid reversal at a dead center-the more abrupt the shorter the connecting rods are - the asymmetry of the movement with respect to the dead points.) In the sketched in Fig. 2 opposed piston engine inlet and outlet piston 40 and 40 '- respectively driven by two crankshafts - simultaneously reaching the OT, however offset by 180 ° crank rotation to reach the UT. This leaves a lot of time for the gas changes, which greatly widens the available engine speed range compared to the JUMO 205. In the exemplary embodiment illustrated in FIG. 2, the engine sucks in air and compresses it with exhaust gas turbochargers that operate in burst mode. The air is passed into a charge air cooler and fed from there via the inlet 60 to the cylinder (shown is only one cylinder, there may be several), in whose supply lines already a certain amount of fuel can be injected, which alone but not for a Ignition would suffice. This additional injection would on the one hand in the

Main injection reduce the amount of fuel required and thus facilitate their atomization; on the other hand, the charge air, possibly only during the compression by the piston, would be cooled by the evaporation of the fuel, which would reduce the required compression work. The charge air (possibly not necessarily) enriched with (somewhat) fuel, therefore, enters a cylinder when its inlet piston releases the intake passage (s) 60, which incidentally may be designed to be in charge of the charge air (or lean charge) (at this time, the exhaust port (s) 80 are already closed and the exhaust piston is moving in the TDC direction.) Thereafter, the intake piston at the UT reverses and also moves in the direction of TDC, which it simultaneously engages with

Outlet piston reached. While the intake and exhaust pistons are near TDC, the main injection begins. For example, the

Start main injection before TDC and also complete a few degrees (in Omega) before TDC.

This is inventively (electronically) controlled so that the

Autoignition leads straight to a maximum combustion chamber pressure, if during the power stroke, the lever ratio dOmega / ie is as small as possible, which according to the invention substantially as early as possible after reversal of both Piston at their OT is the case. Then the speed of expansion of the working gas in the power stroke is already maximum immediately after the TDC.

If injection and mixture formation without self-ignition are completely within the compression stroke, compression ignition can be used. The kinematics of the "half rhombic gear" (ie the two double crankshafts, see Fig. 2) is particularly suitable for its execution, also because in addition to the expansion and the compression at the end of the compression stroke is particularly rapid (unlike conventional crank drives is the maximum Compression speed dV / dt comparatively short before TDC and residence time near TDC is particularly low) .This greatly reduces the risk of pre-ignition and generally increases controllability.At the end of expansion, the exhaust piston releases the exhaust ports and the exhaust gases become the impact turbine Not only does it extract work by expanding the exhaust gas, it also helps in the evacuation of the combustion chamber, while still hot exhaust gas exiting the thrusters is collected in the pitot tube and used to flow the turbine, and the engine can also be equipped with exhaust valves As a result, the dead volume in the (exhaust) lines, and the asymmetry of the intake and exhaust piston motions on TDC is no longer required, as purge losses are avoided rather than a passage difference between the pistons through the valve (s). In this picture the inputs and

Outlet pistons, including their associated crankshafts,

operated mirror-symmetrically, which at any number of cylinders one

Superb mass balance allows. Furthermore, the possible

Removal of lubricant through the outlet channels prevented, which otherwise wanted to be suppressed by other design measures. However, such designs are more complex and thermally less resilient. The following summarizes in a nutshell, why the engine has the above advantages and also has other advantageous properties that are generally appreciated in internal combustion engines.

High efficiency: This results from the combination of

Combustion combustion (optimal Otto process) with the high compression of a diesel engine (diesel) .- In the design as valveless two-stroke piston engine also accounts for friction losses for the valve train, and the heat losses through the cylinder wall, compared for example with four-stroke engines same displacement (per cylinder ), lower. In addition, a very high working medium pressure and thus a very favorable ratio between working and Reibmitteldruck be represented. In addition, the hot working gas is expanded much faster (for example with the help of a

Diamonds transmission. According to the embodiment discussed above, a piston can reach its highest speed already a few degrees after TDC), which further contributes to the reduction of wall losses.

High power density: This results mainly from the possible

Construction as a two-stroke engine. According to the embodiment discussed above as a backlash-free piston engine particularly high power densities can be achieved because (high) charges are possible (outlet already closed when inlet opens) and with sufficient compression and high speeds. Because of the smaller stroke of the individual pistons in the opposed piston engine higher speeds are easier to achieve (and the

Moments of inertia of the piston drives significantly lower) than in

Piston engines whose cylinders have only one piston each. At the

Diesel engine performance would be limited inter alia by the maximum speed (which by the slow burning process

(Diffusion flame) is limited) and possibly also by the thermal and mechanical load capacity of the valves. With a very fast Combustion and without valves performance is mainly due to the thermal load capacity of the pistons, in particular the outlet piston, as well as the stability of the bearing with respect to the "force peaks", which result from the hard combustion.For the invention, however, the bearings feel the force maxima, while the lever ratio Especially short - the maximum force exerted on the piston due to the combustion chamber pressure beats "in the movement" instead of the bearings. Used as a piston drive (half)

Further, it is possible to use a piston with a piston rod, which can substantially simplify the supply of the liquid to the piston crown (for example by cutting coolant through a labyrinth seal into a hole in the bore)

Piston rod is introduced). If the continuous liquid cooling of the piston crown succeeds, the limits of the power density of this engine are very high. This is even more so than that can supply by high pre-compression and at a quasi-compression ratio of the actual engine, the engine of a power turbine with standing under high pressure, hot working gas. It can be constructed in this way a turbo-compound machine, in which a large part of the power is generated at the power turbine, and turbines can have a very high power density. This design is also promising in terms of efficiency: at temperatures that exceed the range of application of gas turbines, the high-pressure working gas is first in the "robust"

Piston engine expands until the working gas temperature is compatible with a gas turbine. During the subsequent expansion in the utility turbine, its very high isentropic efficiency comes into its own.

High torque: A particularly high maximum torque is mandatory, because a particularly high combustion pressure is achieved with a particularly favorable lever ratio. A high mean torque results from the high mean pressure (no flushing losses at the Two-stroke process, therefore charging possible, due to the possible absence of valves, etc. also high charging possible).

The engine according to the example described above can be lubricated like usual four-stroke engines (true separate lubrication).

Claims

claims

1 . Reciprocating engine with

at least one cylinder (50) and

a piston (40) guided in the cylinder, which performs a periodic lifting / lowering movement (dh / dt) between a top dead center (TDC) and a bottom dead center (TDC);

a gear (10, 20 30) for converting the lifting / lowering movement (dh / dt) of the at least one piston (40) into a rotational movement (dOmega / dt) corresponding to an angle-dependent gear ratio (dOmega / dh) and

a fuel injection system (70),

wherein the system for fuel injection is set so that in each working stroke of the piston, the majority of the fuel is injected in a period of time which is less than or equal to the respective Zündverzugszeit, and wherein

the transmission is designed such that immediately after reaching top dead center, the transmission ratio (dOmega / dh) is lower and / or a minimum transmission ratio (dOmega / dh) is reached earlier than when using a conventional crankshaft at the same maximum piston stroke.

2. The engine according Anpruch 1, wherein the plant to the

Fuel injection is set so that an auto-ignition occurs after or at the top dead center and the pressure in the cylinder during the power stroke at a piston position is maximum, to which the transmission has the shortest gear ratio (dOmega / dh).

3. The engine according to claim 1 or 2, characterized in that it is designed as a two-stroke engine

4. The engine according to any one of claims 1 to 3, characterized in that it is designed as an opposed piston engine, in which two mutually associated pistons are guided in a cylinder.

5. The engine according to claim 4, characterized in that a

Charge change is effected by the two pistons release inlet and outlet ports in the cylinder,

wherein the transmission is designed such that mutually associated pistons reach their top dead centers and thus a maximum compression almost simultaneously, offset their bottom dead centers on the other hand.

6. The engine of claim 5, wherein a piston releases the exhaust passage (s) first and then closes again before the other piston associated therewith opens the intake passage (s).

7. The engine according to any one of claims 1 to 6, wherein the transmission is a rhombic gear.

8. The engine according to any one of claims 1 to 6, wherein each piston has two connecting rods, wherein each connecting rod is coupled to a crankshaft and both crankshafts, for example via gears, coupled and

are synchronized.

Characterized in that it operates entirely or predominantly as a diesel engine, and which has a system for fuel injection, which is so dimensioned that with each power stroke, a large part of the injection quantity can be injected in a period of time which is less than or equal to respective ignition delay time is

10. piston engine according to claim 8, characterized in that it

has at least one working piston, which is driven differently than with a conventional crank mechanism. In this case, this other drive is characterized by, measured at the position of the working piston earlier than conventional crank mechanisms after reaching the top dead center the best possible leverage ratio (lowering the piston to dl forces the smallest possible change in the drive shaft rotation angle) to own.

Furthermore, the fuel injection is controlled so that the maximum cylinder pressure occurs as accurately as possible when the cheapest

Lever ratio is given (s.o., which means with: "[...] if a given cylinder pressure the highest possible torque [on the drive] exercises").

1 1. Piston engine according to claim 9, characterized in that it is designed as a two-stroke engine

12. Piston engine according to claim 9, characterized in that it is designed as an opposed piston engine

13. Piston engine according to one of claims 9 to 12, further characterized by having no inlet or outlet valves (the "intentional nailing" enormous mechanical and in the case of / the

Exhaust valve (s) (s) would also be exposed to high thermal loads).

14 piston engine according to claim 13, characterized in that the charge exchange is effected by the working piston release inlet and outlet channels. In this case, the piston drives are configured according to claim 2 such that mutually associated working pistons reach their top dead centers (ie, the maximum compression ratio) almost simultaneously, but offset their bottom dead centers. In this case, a working piston must release the / the outlet channels first and then close again before the associated other piston opens the / the inlet channels.

15. Reciprocating engine with

at least one cylinder (50) and

a fuel injection system (70),

wherein the fuel injection system is set so that in each stroke of the piston, the majority of the fuel is injected in a period which is less than or equal to the respective Zündverzugszeit, so that a self-ignition occurs after or when reaching top dead center,

and

wherein the transmission and the fuel injection are coordinated so that after the compression of the pressure in the cylinder at a

Maximum piston position at which the transmission has the shortest ratio (dOmega / dh).