Internal combustion engine and method for operating an internal combustion engine

Abstract

An internal combustion engine for operation in two-stroke mode has a first cylinder (1), which defines a first combustion chamber, and a second cylinder (11), which defines a transfer chamber, which are fluidically connected to each other via a transfer port (4). Furthermore, a first piston (2), which is movable along a longitudinal axis of movement in the first cylinder (1), and a second piston (12), which is movable along a longitudinal axis of movement in the second cylinder (11), are provided, the pistons being mechanically connected to each other by means of a crankshaft (6). The internal combustion engine also has a crankcase (9) in which the crankshaft (6) is arranged, as well as a second valve (7) associated with the second cylinder (11) and a third valve (3) associated with the transfer port (4), each of the valves (3, 7) being adjustable between an opening position that allows a fluid path and a closing position that closes this fluid path.

Description

[0001] The invention relates to an internal combustion engine according to claim 1 and a method for operating the internal combustion engine according to claim 8.

[0002] Internal combustion engines have achieved a high level of technology over the years and have found numerous applications due to their numerous advantages. However, they clearly still have further development potential. Efficiency, especially under partial load conditions and thus carbon dioxide emissions, can still be improved; the amount of exhaust emissions, soot emissions, and the number of components, and thus production costs, can still be reduced. These problems influence each other; changes in efficiency also cause changes in emissions, and vice versa. A distinction must be made between diesel engines and gasoline engines. Diesel engines are more efficient than gasoline engines. However, nitrogen oxide and soot emissions are higher than those of gasoline engines.

[0003] To remedy this, urea injection systems with special urea tanks and soot filters are used, which, due to their high manufacturing complexity, lead to higher production and operating costs. Urea injection has long been used in commercial vehicles. Therefore, many manufacturers are striving to reduce emissions and fuel consumption through internal engine modifications.

[0004] One way to achieve this is through valve adjustment, which changes the opening and closing times of the valves relative to the crankshaft. Another way to solve the problems mentioned above is to change the compression ratio during operation. Compression affects both efficiency and pollutant emissions. A relatively high compression ratio is necessary for cold starts, which is no longer needed when the engine is warm. Compression ratio can also be reduced at partial load and when idling. Changing the compression ratio by inserting an additional piston into the compression volume has long been known and has often been used. A large proportion of the internal combustion engines currently in production are equipped with exhaust turbochargers, mechanical compressors, or charge fans. These serve to supercharge and increase power in a relatively small displacement.Piston valves are very common in fluid power and steam engines, but in internal combustion engines, poppet valves are mostly used.

[0005] Internal combustion engines with at least two cylinders, usually three or even more, have been around for a long time. What these engines have in common is that they have many valves, connecting channels, or pistons that are complex to manufacture, resulting in high development and manufacturing costs.

[0006] For example, US 2 267 461 A relates to two-stage two-stroke internal combustion engines and seeks to provide a two-stage two-stroke internal combustion engine in which the reciprocating and rotating masses automatically balance themselves, which is intended to enable smooth and rapid operation without excessive vibrations or stress on the parts.

[0007] WO 2010 / 145 628 A1 relates to a motor vehicle having an internal combustion engine and at least one electromechanical energy converter, which are used in conjunction to propel the motor vehicle.

[0008] EP 1 961 943 A1 also relates to an internal combustion engine with improved efficiency and a compact design.

[0009] The object of the present invention is therefore to provide a simpler internal combustion engine that essentially allows for widespread and inexpensive construction methods. Furthermore, the internal combustion engine should generate the highest possible efficiency and minimize emissions of harmful combustion products such as nitrogen oxides and soot.

[0010] This object is achieved by an internal combustion engine according to claim 1 and a method for operating the internal combustion engine according to claim 8.

[0011] Main features of the invention are defined in independent claims 1 and 8, respectively. Embodiments are the subject of claims 2 to 7.

[0012] "Fuel-air mixture" refers to a combustible gas before combustion. "Fuel gas" refers to a gas after combustion.

[0013] In an internal combustion engine for operation in two-stroke mode, comprising a first cylinder defining a first combustion chamber and a second cylinder defining a transfer chamber, which are fluidically connected to one another via a transfer opening, a first piston movable along a longitudinal axis of movement in the first cylinder and a second piston movable along a longitudinal axis of movement in the second cylinder, wherein the pistons are mechanically connected to one another by means of a crankshaft, a crankcase in which the crankshaft is arranged, a first valve assigned to the first cylinder, a second valve assigned to the second cylinder, and a third valve assigned to the transfer opening, wherein each of the valves is adjustable between an open position releasing a fluid path and a closed position closing this fluid path,wherein the internal combustion engine is designed to burn flammable liquids, such as diesel fuel, marine diesel oil, biodiesel, gasoline, and / or two-stroke mixture, as well as flammable gases, such as hydrogen, LPG, natural gas, and / or wood gas, a camshaft is provided according to the invention, which is designed to cooperate with at least one of the valves, and at least one lifting means, which is designed to cooperate with the camshaft, such that it is designed to change the distance of the camshaft from at least one cylinder in order to change the compression.

[0014] By means of the internal combustion engine according to the invention and the transfer port, the combustion gases become cooler as they expand from the first cylinder into the second cylinder. The temperature also drops as the combustion gases cool on the walls of the second cylinder. This expansion distributes the energy content of the combustion gases and their pressure between the two cylinders, reducing the loads on the pistons, crankshaft, cylinder head, and cylinder block. This means that they do not need to be constructed as sturdily as in other internal combustion engines. The internal combustion engine according to the invention therefore exhibits high efficiency and emits fewer harmful combustion products.

[0015] The first valve can connect an external chamber of the cylinder to one or more cylinders and provide fluid and / or fresh air supply. The pistons are reciprocating pistons with bottom and top dead centers in a conventional manner.

[0016] According to a further development of the internal combustion engine according to the invention, the first valve is designed as an intake valve and the second valve as an exhaust valve. This allows for a compact design of the internal combustion engine. When used in an internal combustion engine based on the two-stroke principle, the first valve can also be an exhaust valve.

[0017] According to a further development of the internal combustion engine according to the invention, the crankshaft has at least two throws, preferably from 60° to 30°, more preferably from 45°, and a lead of the second piston ahead of the first piston. This results in a greater torque in the cylinder due to the larger effective lever arm then present.

[0018] According to a further development of the internal combustion engine according to the invention, the second valve is arranged and / or configured such that it fluidically connects the second cylinder directly and the first cylinder indirectly via the third valve to a connecting channel. This allows the second valve to fulfill a dual function.

[0019] According to a further development of the internal combustion engine according to the invention, it comprises a third cylinder defining a second combustion chamber, a third piston movable along a longitudinal axis of movement in the third cylinder, the pistons being mechanically connected to one another by means of the crankshaft, a connecting channel via which the second cylinder is fluidly connected to the third cylinder, a fourth valve associated with the third cylinder, and a fifth valve associated with the connecting channel, each of the valves being adjustable between an open and a closed position. This allows the second cylinder to function as an overflow cylinder for the other two cylinders, which can be configured as working cylinders.

[0020] According to a further development of the internal combustion engine according to the invention, it is designed such that after injection of fuel into the first cylinder and before or with ignition of this fuel, the third valve can be adjusted to its open position and / or that after injection of fuel into the third cylinder and before or with ignition of this fuel, the fifth valve can be adjusted to its open position.

[0021] According to a further development of the internal combustion engine according to the invention, one or more of the valves are selected from the group comprising: poppet valve and piston slide valve.

[0022] Furthermore, a method is proposed for operating an internal combustion engine, preferably an internal combustion engine according to claim 1, in the two-stroke operating mode, wherein the internal combustion engine comprises at least: a first cylinder defining a first combustion chamber, and a second cylinder defining a transfer chamber, which are fluidically connected to one another via a transfer opening, a first piston movable along a longitudinal axis of movement in the first cylinder, and a second piston movable along a longitudinal axis of movement in the second cylinder, wherein the pistons are mechanically connected to one another by means of a crankshaft, a crankcase in which the crankshaft is arranged, a second valve assigned to the second cylinder, and a third valve assigned to the transfer opening,wherein each of the valves is adjustable between an open position releasing a fluid path and a closed position closing this fluid path, comprising the following steps: • Bar 1: ◯ Intake of a fluid-fuel mixture into the first cylinder, ◯ Moving the first piston in its upward direction, thereby compressing the fluid-fuel mixture in the first cylinder, ◯ Moving the second piston in its upward direction, thereby expelling exhaust gas from the second cylinder via the second valve, ◯ Adjusting the third valve to its closed position as soon as the second piston has reached its top dead center, ◯ Suction of a fluid-fuel mixture into the crankcase or a cylinder block, ◯ Ignition of the fluid-fuel mixture in the first cylinder before the first piston reaches its top dead center, ◯ Adjusting the third valve to its open position, ◯ thereby overflowing the contents of the first cylinder via the overflow opening into the second cylinder, • Bar 2: ◯ Adjusting the first piston in its downward direction, ◯ Adjusting the second piston in its downward direction, ◯ thereby compressing the fluid-fuel mixture in the crankcase or in the cylinder block, ◯ Directing the compressed fluid-fuel mixture from the crankcase or from the cylinder block into the first cylinder before the first piston has reached its bottom dead center, ◯ thereby overflowing the burnt mixture from the first cylinder via the overflow opening through the second cylinder into an exhaust, and ◯ Adjusting the third valve to its closed position.

[0023] The advantages described above with regard to the internal combustion engine apply equally to the method defined here, to which reference is hereby made.

[0024] Further features, details, and advantages of the invention will become apparent from the wording of the claims and from the following description of exemplary embodiments with reference to the drawings. They show: Fig. 1.A1 a longitudinal sectional view through an internal combustion engine of a first embodiment, which is not the subject of the invention, for operation in the four-stroke mode during a first stroke, Fig. 1.A2 a sectional view through a crankcase according to Fig. 1.A1, Fig. 1.B1 a longitudinal sectional view through the internal combustion engine according to Fig. 1.A1 during a second bar, Fig. 1.B2 a sectional view through a crankcase according to Fig. 1.B1, Fig. 1.C1 a longitudinal sectional view through the internal combustion engine according to Fig. 1.A1 during a second bar, Fig. 1.C2 a sectional view through a crankcase according to Fig. 1.C1, Fig. 1.D1 a longitudinal section through the internal combustion engine according to Fig. 1.A1 during a third bar, Fig. 1.D2 a sectional view through a crankcase according to Fig. 1.D1, Fig. 1.E1 a longitudinal sectional view through the internal combustion engine according to Fig. 1.A1 during a fourth bar, Fig. 1.E2 a sectional view through a crankcase according to Fig. 1.E1, Fig. 2 is a longitudinal sectional view through an internal combustion engine of a second embodiment, which is not the subject of the invention, for operation in the four-stroke mode, Fig. 3 a longitudinal section through the internal combustion engine according to Fig. 2, Fig. 4.A a view of a piston valve, Fig. 4.B a sectional view of the piston valve according to Fig. 4.A, Fig. 4.C a view of a piston valve, Fig. 4.D a sectional view of the piston valve according to Fig. 4.C, Fig. 4.E a view of a piston valve, Fig. 4.F a sectional view of the piston valve according to Fig. 4.E, Fig. 5.A a sectional view through a crankcase according to Fig. 1.A1, Fig. 5.B another sectional view through a crankcase according to Fig. 1.A1, Fig. 5.C a piston valve according to Fig. 5.B, Fig. 5.D a cam disk according to Fig. 5.B, Fig. 6.A a sectional view of a cylinder head, Fig. 6.B another sectional view of a cylinder head, Fig. 7.A is a longitudinal sectional view through an internal combustion engine of a third embodiment for operation in the two-stroke mode, Fig. 7.B a longitudinal section through the internal combustion engine according to Fig. 7.A, Fig. 8.A is a longitudinal sectional view through an internal combustion engine of a fourth embodiment for operation in the two-stroke mode, and Fig. 8.B a longitudinal section through the internal combustion engine according to Fig. 8.A.

[0025] In the following, the Fig. 1.A1 to 1.E2 an internal combustion engine according to the invention is described. A further example is shown in Fig. 2 and then explained.

[0026] Fig. 1.A1 above shows an overview drawing of the internal combustion engine with a side view. The internal combustion engine comprises a crankcase 9 and at least two cylinders 1, 11 that are mounted closely next to one another. In these cylinders, the pistons 2, 12 move. These pistons exert pressure on the common crankshaft 6 via connecting rods 5, 15, thereby generating torque on the crankshaft 6. A first cylinder 1 acts, as in a known internal combustion engine, as the working cylinder of a two-stroke gasoline or two-stroke diesel internal combustion engine. A second cylinder 11 is connected to the first cylinder 1 by a transfer port 4. A cylinder head 8 is attached to the crankcase 9 and carries the camshaft 23, its drive and lifting device with side parts 51 and 52, and the control valves 13, 3, and 7. The drive and lifting device with side parts 51 and 52 are each attached to the cylinder head center section with plate-encompassing adjustment slides 27 and 28.The valves are pressed down by cams 24, 25, and 26 via bucket tappets 47 and rollers 48 with holders 49, and then pushed up again by valve springs 46. The camshaft 23 is driven by a timing chain 30 via the gear 31 attached to the camshaft 23 and by the gear 32 attached to the crankshaft 6 at half the crankshaft speed. A hydraulic cylinder 29, acting as a lifting means on a mounting bracket on a mounting plate of the adjusting slide 28, rotates a shaft 22, via a bell crank 21, which carries a gear 71 and 72 at each end. These gears 71 and 72 engage a rack 67 and 68, respectively, with which the camshaft 23 can be pushed up and down, whereby a piston slide valve 13, which will be described in more detail later, opens and closes the inlet 17 to cylinder 1. Another piston valve 3 opens and closes the overflow channel 4 from cylinder 1 to cylinder 11.A piston valve 7 acts as an exhaust valve and opens and closes the connecting channel 14, to which a turbocharger 35 can optionally be attached to the cylinder head 8 if required. A centrifugal separator 36 can also be optionally installed on the turbocharger outlet side as a soot separator. The piston valves 13 and 7 can optionally be replaced with conventional poppet valves. The camshaft 23 actuates the valves 13, 3, and 7 via the cams 24, 25, and 26.

[0027] The Fig. 1.A1 to 1.E2 represent a typical run through the various strokes in the sequence of intake, compression, ignition / overflow, work, exhaust. During intake, Fig. 1.A1 first opens the intake valve 13 to cylinder 1 with piston 2 and connecting rod 5, and the overflow valve 3 to the overflow port 4, which leads to cylinder 11 with piston 12, which is held by the piston pin 16 on the connecting rod 15. Pistons 2 and 12 move downward, thereby filling both cylinders 1 and 11 either with fresh air when using injection systems or with a fuel-air mixture when using carburetors. Piston 12 advances piston 2 by approximately 45° at the crank angle of the crankshaft 6. This angle does not necessarily have to be 45°; it is shown here as an example; other angles, including 0°, i.e., without advance, are also possible. Fig. In 1.A2 to 1.E2 this is shown in the lower part of the image in a section through the crankcase 9 and the piston 12 as well as the connecting rod 15 and the crankshaft 6, whereby the position of the connecting rod 5 and the crankshaft 6 (dashed lines) are also shown for illustration and orientation.

[0028] The balance weights normally required on the crankshaft 6 are hidden here. When the piston 2 reaches the bottom dead center, the intake valve 13 is closed, then compression takes place in both cylinders 1 and 11, this is in Fig. 1.B shown in side view and below for the section through piston 12. Both pistons 2 and 12 move upwards until piston 12 has reached top dead center. Piston 2 still has a significant compression volume above it and has not yet reached the ignition position. Due to the upward movement of piston 12 and its compression of the air or fuel-air mixture from cylinder 11 into cylinder 1, considerably more air or fuel-air mixture was compressed in this volume in cylinder 1 than was possible through the compression of piston 2 alone. This volume is now closed off by pressing valve 3 down with the help of camshaft 23 and is further compressed by pushing piston 2 up further.

[0029] The valve, piston and connecting rod position is in Fig. 1.C above ( Fig. 1.C1) in side view and below ( Fig. 1.C2) is shown in a section through the crankcase 9. In a diesel engine, when piston 2 has reached the vicinity of top dead center, depending on the operating conditions, the first fuel injection is triggered, thus resulting in ignition. In a gasoline engine, either the fuel is injected and ignited by the spark plug, or, in a carburetor, the existing fuel-air mixture is ignited by the spark plug. The time interval or the crankshaft angular distance to top dead center of the individual injection or ignition points is controlled by the engine electronics or the cam shape of the camshaft 23. However, fuel injection and ignition only occur in cylinder 1.

[0030] Shortly after the ignition in the first cylinder 1, the valve 3 is opened to the aforementioned connecting channel 4 to the second cylinder 11, whose piston 12 can move in the same way as the first piston 2, parallel to it or at an angle leading to it. This stroke is in Fig. 1.D, where the arrows in the pistons indicate the direction of movement of the pistons, as in the other drawings. This stroke is the only working stroke in this type of internal combustion engine. Valve 3 is a piston slide valve, already known in another form and described in more detail later, or a likewise known poppet valve, whereby at least the front part of this should be made of a high-temperature resistant material. The working pistons 2 and 12 are sealed by piston rings in the cylinder head 8. To ensure that the piston rings of the piston slide valves can be guided more effectively, guide webs 94 are provided in the sides of the transfer openings. The sealing by piston rings also solves the problem of sealing and tightness against byflow, which most slide valve designs had.Through the opening of valve 3, the burning fuel-air mixture flows into the connecting channel 4 between the two adjacent cylinders 1 and 11 and then into the neighboring cylinder 11 itself. Due to the increase in volume, it cools according to general gas laws and the larger wall surface, but still exerts a high pressure on the piston 12 in the neighboring cylinder 11. As a result, a pressure acts on the pistons 2 and 12 in both adjacent cylinders 1 and 11, which generates a torque on the common crankshaft 6 via the two connecting rods 5 and 15 belonging to the pistons 2 and 12. However, this pressure is considerably lower than if combustion only occurred in the first cylinder 1, in which the first ignition takes place. If the dimensions of the two cylinders 1 and 11 are the same, the pressure is reduced by approximately half.This significantly lowers the maximum pressure in the internal combustion engine than in an internal combustion engine without transfer ducts. This allows the engine to be built lighter, as the loads are less severe. After the transfer, the burning fuel-air mixture expands in both cylinders 1 and 11 and performs work on pistons 2 and 12 as they move away from cylinder head 8. Piston slide valves have the advantage over poppet valves in that, due to their protected and cooled position in cylinder head 8 during retraction, they are less exposed to the hot combustion gas flow and also open up a larger transfer opening.

[0031] At the bottom dead center of the piston 2, the exhaust valve 7 of the connecting channel 14 in the cylinder 11 is opened as in Fig. 1.E shown. Fig. 1.E below also shows the connecting rod position reached at the bottom dead center of piston 2. Due to the movement of piston 12 and then piston 2 from bottom to top dead center, the combusted fuel-air mixture, i.e. the combustion gases, are now conveyed through the transfer channel 4 and the connecting channel 14 into the exhaust or an exhaust turbocharger 35. When top dead center of piston 12 is reached (in the crankshaft angle), the exhaust valve 7 is closed and the inlet valve 13 to cylinder 1 is opened again, cf. Fig. 1.A1. The overflow valve 3 to cylinder 11 remains open. New air or a new fuel-air mixture then flows into cylinder 1 and further through connecting channel 4 into cylinder 11 until piston 2 reaches bottom dead center again. With a suitable selection of the camshaft profile or camshaft timing, a portion of the exhaust gas not yet expelled can remain in cylinder 1 and later serve to reduce nitrogen oxides, particularly in diesel engines.

[0032] Then the intake valve 13 is closed again and the pistons 2 and 12 compress the air or the fuel-air mixture trapped in the cylinders 1 and 11 on their way to the top dead center (see). Fig. 1.B1. When piston 12 reaches top dead center, valve 3 is closed. Due to the characteristics of the piston engine and the crankshaft, this occurs 40-50° before the angle of top dead center of piston 2. After that, compression in cylinder 1 with piston 2 is not much higher, but sufficient for ignition (see [Fig. Fig. 1.C1. In a diesel engine, when piston 2 is close to top dead center, the fuel is injected into cylinder 1 and ignites itself. In a four-stroke gasoline engine, the fuel is also injected into cylinder 1 above piston 2 before dead center is reached, but is then ignited by the ignition system. In a carburettor engine, the fuel-air mixture is formed during intake and then ignited after compression. As described above, valve 3 is opened again shortly after ignition so that the burning fuel-air mixture can flow through the transfer channel 4 into the adjacent cylinder 11, where piston 12 has already moved slightly downwards (cf. Fig. 1.D1. At the end of the downward movement of piston 2 at bottom dead center, exhaust valve 7 opens, and the combusted gas is expelled from cylinder 1 via transfer port 4 by piston 2, and from cylinder 11 by piston 12 via connecting port 14. Valves 3 and 7 are open, see Fig. Fig. 1.E1. This entire process is then repeated.

[0033] In a diesel engine, the primary injection in cylinder 1 is direct, while the further path to cylinder 11 corresponds to pre-chamber injection or swirl chamber injection. Due to the larger cooling wall surface in cylinder 11, the gases cool down more than through the expansion of the burning fuel-air mixture alone. The piston 12 in cylinder 11 then acts like a familiar charge pump for supercharging the internal combustion engine, or like a compressor. However, it also exerts its effect at low engine speeds. The result of this process is approximately twice the volume of compressed air and subsequently also of the combustion gases distributed across two cylinders, a significantly lower pressure after ignition in both cylinders 1 and 11, and a significantly lower temperature than in just one cylinder. This makes supercharged operation possible for all sizes of internal combustion engines, even smaller ones.However, the "charge pump" is not only used for compression, but also doubles its use during the power stroke to generate torque. By appropriately shaping the piston 12 with "noses" that fit into the necessary recesses, for example, in the transfer port 4, the dead volume in the cylinder 11 above the piston 12 can be kept small.

[0034] The camshaft 23 with the cams 24, 25, and 26, through its rotation, causes the opening and closing of valves 3, 7, and 13. Adjustment mechanisms or adjustment slides are mounted on their bearings as lifting means 27 and 28, both for a linear upward and downward height adjustment, which allows a compression change when using piston slide valves, and for a rotational adjustment of the opening and closing angle of the valves relative to the crankshaft 6. The compression change is achieved by pushing the pistons of the piston slide valves further out or in into the compression chamber by lowering or raising the entire camshaft 23. The cylinder head cover 88 closes off the camshaft 23 and its mount. The process of changing the compression will be explained in more detail below.

[0035] Previous internal combustion engines have relatively high combustion and exhaust temperatures, which reduce efficiency and cause high levels of pollutants. To reduce exhaust temperatures and thus increase efficiency, various measures have been implemented in the internal combustion engine according to the invention, which are highlighted here again: After ignition, the volume of the burning fuel-air mixture is significantly increased by the expansion into the neighboring cylinder 11 by the opening of valve 3. Pistons 2 and 12 are moved downwards and the burning gas cools down due to the work output, the increase in volume and the heat transfer to the walls of cylinders 1 and 11. At the bottom dead center of both pistons 2 and 12, the temperature of the gas is then significantly lower due to the larger volume of the two cylinders 1 and 11 than if the combustion gas had expanded only in cylinder 1. The pressure in both cylinders 1 and 11 is also significantly lower than if only expansion had been possible in cylinder 1. This becomes clear when one looks at the p-V diagrams of both the Otto cycle and the Diesel cycle.This has two simultaneous effects: first, the combustion temperature and thus nitrogen oxide production is lowered; second, the exhaust gas temperature is lowered, and efficiency, excluding additional friction effects, should increase. A simple formula for the Carnot efficiency η. c of an internal combustion engine is: ηc=1−TnTh, where T n the lowest and T h is the highest temperature occurring in the process in Kelvin. If T n the exhaust gas temperature and T h The combustion temperature (approximately 2200 K) is the highest, it is easy to see that the lower the exhaust gas temperature, the higher the efficiency. Not only the exhaust gas but also the entire internal combustion engine takes on a lower temperature, since the heat dissipation to the walls of cylinders 1 and 11 occurs at a significantly lower temperature than if only cylinder 1 were involved.

[0036] A further beneficial effect is the reduction in soot that occurs in today's injection engines, both in Otto engines and diesel engines. The second measure, the compression change through the linear adjustment of the camshaft 23 allows high compression, for example during start-up, e.g. cold start of an internal combustion engine or at high power levels, and lower compression when the engine is warm or less power, e.g. when idling. The compression change occurs, as already mentioned above, by raising or lowering the camshaft 23. The camshaft 23 presses the piston slide valves 3, 13 and 7 downwards or allows them to slide upwards through spring pressure or desmodromic actuation. When compression is increased, all piston valves are pressed downwards by the linear movement of the camshaft 23 and thereby reduce the volume at top dead center above the piston in cylinders 1 and 11.This is easily achieved with piston valves, as they can be guided on the cylinder head 8 in such a way that they have no lower stop, especially with desmodromic actuation. A displacement of the piston valves of just a few mm is sufficient to significantly change compression by 20% in conventional passenger car internal combustion engines. Reducing compression can also lower the combustion temperature and exhaust gas temperature.

[0037] Further measures have been taken to reduce pollutants. The exhaust gas turbochargers 35 can also be designed to remove soot or parts thereof. For this purpose, conical centrifugal separators 36 are attached to the outside of the turbocharger housing 35, where the exhaust gases flow out, with their central axis facing downwards. The rotation of the turbochargers centrifugally hurls the soot particles from the inside onto the inner housing wall of the centrifugal separator 36, where they can be removed by suitable shaping with internal guide vanes. The centrifugal separators should consist of at least two parts: a removable inner part, to which the soot particles can adhere, for example, and later be blown off or washed away, and the outer housing, at the lower end of which the exhaust gases are passed on to the catalytic converter or to the already known exhaust gas recirculation to the air intake or to a soot filter.Any soot particles that slide down can also be collected in a container at the bottom that can be emptied from the outside.

[0038] The intake ports, transfer ports, piston crowns and cylinder heads are provided with small elevations (turbulators, dimples) that ensure thorough mixing of the fuel-air mixture or swirl the air. These turbulators are well known in the aviation industry and are used to change from laminar to turbulent flow; they are known as dimples on golf balls to increase their flight distance. In turbulent flow or when the fuel jets impinge, the mixtures are mixed more thoroughly than in laminar flow, so that the well-known "knocking" that occurs during unwanted ignition in gasoline engines can be reduced. In diesel engines, too, such air swirling, as is already achieved in other known ways, for example in special piston shapes with the swirl chamber mentioned above, can help to better mix the injected fuel droplets with the combustion air.These small elevations have another effect. They ensure better heat transfer, meaning the pistons can be cooled by the impact of the fuel droplets and the larger surface area. Both effects ensure greater energy transfer and thus improve the overall efficiency of the internal combustion engine. Another way to improve atomisation of the fuel droplets is not to just atomise them in the air during injection, but to let them hit the obstacles on the piston directly. For this purpose, elevations are added to the pistons as mentioned above, or the pistons are provided with "noses" which the injected fuel droplets hit directly and are further reduced in size. The injection nozzles currently in use with multiple jets from different bores are particularly well suited for this.This should reduce the annoying ignition delay, especially with diesel fuel.

[0039] The camshaft adjustment, which is known in another form, is also implemented in the direction of rotation in order to change the filling times of cylinders 1 and 11 relative to the position of the crankshaft 6. This serves to optimize combustion. This is achieved by the already known change in the effective length of the camshaft timing chain 30. The camshaft timing chain 30 is tensioned on one side and loosened on the other side by chain tensioners. This reduces the angle between the crankshaft and camshaft on the tensioned side, and the timing of the valve opening is offset relative to the crankshaft. By alternately operating the chain tensioners, the camshaft offset relative to the crankshaft can be changed.However, the compression adjustment is still maintained because the chain tensioners can also be operated synchronously and thus the camshaft timing chain 30 can be tensioned and loosened as a whole in order to compensate for the change in length caused by raising or lowering the control plates of the camshaft bearings.

[0040] The advantages of the overflow of combustion gases into a neighboring cylinder to improve the properties of an internal combustion engine can be further exploited if the combustion gases of two neighboring cylinders flow alternately into only one middle cylinder. The principle is Fig. 2. Following the previous right cylinder 11 from the Fig. 1, a further cylinder 81 is mounted in a mirror image with respect to the center of the transfer cylinder 11 belonging to the left cylinder 1 and extends the internal combustion engine housing by a further crankshaft throw.

[0041] Fig. Figure 2 shows an overview drawing of the internal combustion engine with three adjacent cylinders, viewed from the side. The internal combustion engine consists of a crankcase 9 and three cylinders (1, 11, 81) arranged close together, in which pistons (2, 12, 82) move, exerting pressure on the common crankshaft (6) via connecting rods (5, 15, 83), thereby generating torque on the crankshaft (6). A first cylinder (1) acts as a working cylinder of a two-stroke gasoline or two-stroke diesel engine, as in a conventional internal combustion engine. The second cylinder (11) is connected to the first cylinder (1) by a transfer port (4). In a mirror image, the third cylinder (81) is connected to the second cylinder (11) by a connecting port (14). A cylinder head 8 is mounted on the crankcase 9, which carries the camshaft 23, its drive and lifting device with side parts 51 and 52 and the control valves 13, 3, 7, 93 and 18.The drive and lifting device with side parts 51 and 52 are each attached to the cylinder head center section with adjustment slides 27 and 28. The valves are pressed downward by cams 24, 25, 26, 84, and 86 via bucket tappets 47 and rollers 48 with holders 49, and then pushed upward again by valve springs 46. The camshaft 23 is driven by a timing chain 30 via the gear 31 attached to the camshaft 23 and by the gear 32 attached to the crankshaft 6 at half the crankshaft speed.

[0042] A hydraulic cylinder 29 on a mounting bracket on the mounting plate of the adjustment slide 28 rotates a shaft 22 via a reversing lever 21, which shaft carries a gear 71 and 72 at each end.

[0043] These gears 71 and 72 engage with a rack 67 and 68, respectively, with which the camshaft 23 can be moved up and down. The cylinder head 8 is covered by the cylinder head cover 88. The camshaft drive with the gear 32 on the crankshaft 6 is sealed oil-tight by the cover 199. The piston slide valve 13, which will be described in more detail below, opens and closes the inlet 17 to cylinder 1. Another piston slide valve 3 opens and closes the transfer port 4 from cylinder 1 to cylinder 11.

[0044] The piston valve 7 acts as an exhaust valve and opens and closes the exhaust port 89 on the side of the internal combustion engine which is in Fig. 3 in section. A turbocharger 35 is optionally mounted on the exhaust port 89, if required, on the cylinder head 8. A centrifugal separator 36 can also be optionally mounted on the turbocharger outlet side as a soot separator. By actuating the piston slide valves 13, 3 and 7 by the camshaft 23 via the cams 24, 25 and 26, the left side of the internal combustion engine is initially used for power output. However, the middle cylinder 11 is not filled with fresh air or fuel-air mixture during the intake stroke, which is then compressed as in the internal combustion engine from the Fig. 1, but here only the combustion gases produced after ignition in cylinder 1 are partially led through the transfer channel 4 into cylinder 11 to perform further work there and to be cooled in the process. The combustion gases are then expelled through the piston slide valve 7 and the exhaust port 89. After that, this cylinder 11 is ready to receive the combustion gases from the right side of the internal combustion engine again. At the same time as the work is performed as the left piston 2 in cylinder 1 and the middle piston 12 in cylinder 11 move down, air is sucked into the right part of the internal combustion engine in the case of injection engines or a fuel-air mixture in carburetor engines. To do this, the inlet valve 18 at the inlet 87 must first be opened by the camshaft 23 with the cam 86. The valve 93 remains closed during intake until the piston 82 in cylinder 81 has reached its bottom dead center.When piston 82 reaches its bottom dead center, valve 18 closes and piston 82 compresses the air or the fuel-air mixture in cylinder 81 as it rises until ignition occurs near top dead center after fuel injection or the ignition spark in a gasoline engine or compression ignition in a diesel engine. Shortly after ignition, valve 93 opens and some of the combustion gases flow through the connecting channel 14 into cylinder 11. Valve 7 and valve 3 are closed shortly before all pistons have reached top dead center. Piston 82 and piston 12 then move downwards due to the pressure of the combustion gases, performing work until both have reached bottom dead center. When bottom dead center has been reached, valve 7 opens and the exhaust gases are expelled through outlet 89 into turbocharger 35 or an exhaust.After the exhaust gases from the right side of the engine have been expelled, valve 7 is closed again, and the middle cylinder 11 can again partially absorb the combustion gases from cylinder 1, in which, during the power stroke of the right cylinder 81 and the subsequent transfer and expulsion of the exhaust gases, the left piston 2 sucked in air or a fuel-air mixture, compressed it, and ignited it. This completes a cycle for generating power in both sides of the engine and can be repeated, creating a continuous sequence of power strokes in all three cylinders of the engine.

[0045] The Fig. 3 also shows a cross-section through the cam 26 of the camshaft 23 and the drive shaft 22 of the camshaft height adjustment for compression change. Fig. Figure 3 shows a cross-sectional view of the cooling channels 79 and 80 in the cylinder head 8, as well as the cooling channels 91 and 92 in the crankcase. The piston pin 16 in the piston 12 also passes through the connecting rod eye of the connecting rod 15, which is pivoted on the crankshaft 6. Valve 7 is driven by the cam 26 via the roller 48 on the bucket tappet. The piston slide valves 13, 7, and 18 can optionally be replaced with conventional poppet valves. The camshaft 23 actuates the valves 13, 3, 7, 93, and 18 via the cams 24, 25, 26, 84, and 86.

[0046] The function of the internal combustion engine according to Fig. 2 and Fig. 3 is similar to the internal combustion engine from the Fig. 1. However, the combustion gases from cylinder 1 flow through the transfer channel 4 alternating with the combustion gases from cylinder 81 through the connecting channel 14 and the opened piston slide valve 93 into the middle cylinder 11. This is thus filled with combustion gases with each crankshaft revolution, so that the combustion gases perform work until bottom dead center and are immediately expelled again through the piston slide valve 7, which is opened after bottom dead center. Therefore, with each revolution of the crankshaft 6, a power stroke occurs for the piston 12 in cylinder 11. Now, the middle cylinder 11 can be used with each crankshaft revolution for further work output and thus also for cooling the combustion gases. The expelled combustion gases can also be used here for the Fig. 1 already shown to drive an exhaust gas turbocharger 35 also with connected centrifugal separator 36 for fine dust, soot etc.

[0047] Just like the one in the Fig. The example of the internal combustion engine with the two cylinders 1 and 11 shown in Figure 1 is also shown in Fig. 2, the camshaft 23 is adjustable both linearly and rotationally in order to be able to change the compression and the filling time relative to the crankshaft 6.

[0048] The advantages of the internal combustion engine according to the invention include: 1. Simple design: The previously used crankcases with oil pan, crankshaft, connecting rods and pistons can continue to be manufactured, fitted with bearings, lubricated and cooled as before. Only the cylinder heads are modified, but they are also largely manufactured and operated using previously used manufacturing processes. The bores for the piston slide valves are easier to manufacture than the bores and valve seats for the poppet valves, which have to be ground in and adjusted very precisely, especially the desmodromically controlled ones. The piston slide valves do not require valve clearance adjusting screws or hydraulic tappets. Rocker arms, finger followers, valve springs and camshafts as well as their drives can be used as before with the poppet valves without any new manufacturing processes. The piston slide valves can be constructed in the same way as conventional pistons with piston rings for sealing.Cooling can be implemented in the same way as with the large working pistons. The material of the piston slide valves can be the same as that of the large pistons, e.g., aluminum, and does not need to be highly heat-resistant like the poppet valves, which are directly exposed to the exhaust gas flow. The air inlets and exhaust outlets can be designed to be more aerodynamically efficient than with poppet valves. 2. Simple compression control: The bores and movement directions of the piston valves are parallel to each other. Therefore, a linear compression change can be achieved by raising and lowering the camshaft. This is considerably simpler and requires less effort than the familiar tilting of the engine block or raising and lowering of the crankshaft with its numerous offsets and bearings. The relatively complicated internal combustion engines according to US367496A, which some engine manufacturers are currently reviving, with their expensive transfer levers, can also be eliminated.

[0049] The design of the piston slide valves according to the invention is described in the Fig. 4.A to 4.F. As already mentioned, the piston slide valves are intended to replace the already familiar poppet valves without significant modifications to the cylinder heads that have been used so successfully to date. Therefore, the design here is very similar to that of the poppet valves. Fig. 4 are left in Fig. 4.A and 4.B each show a piston valve with cut-away tappet 47 and springs 46 in side view ( Fig. 4.A) and on average ( Fig. 4.B) drawn in the closed position. In the middle in Fig. 4.C and 4.D are the side view ( Fig. 4.C) and the cut ( Fig. 4.D). The closing element is the lower part of the valve, which is thicker than piston 40. Adjoining this is a slimmer shaft 41, around which the valve spring 46 can be placed. The piston 40 carries three piston rings, 42, 43, 44, which seal the air supply and exhaust openings. At the upper end of the shaft 41 there is a recess or shoulder 45 into which a carrier for the counterbearing of the valve spring 46 is fitted. The lower part of the valve spring 46 is supported on a snap ring 50 which is held in a groove 74 in the cylinder head 8. A bucket tappet 47, which absorbs the lateral forces of the spring guide, is placed around the upper part of the valve spring 46. In order to prevent the lateral forces from becoming too great due to the friction of the camshaft on the bucket tappet 47, a roller 48 is mounted on the bucket tappet 47 in a holder 49, with which the bucket tappet 47 is guided against the spring pressure of the valve spring 46 by the camshaft 23.

[0050] If lateral forces are still too great, rocker arms with a roller attachment or rocker arm can be used to transmit the camshaft forces to the valve stem 41. To reduce weight, the piston slide valve can also have a bore into which oil can be injected for cooling purposes. This oil can then flow out again through a small bore in the wall of the valve and subsequently serves to lubricate and seal the piston rings 42, 43 and 44. At this point it should also be noted that the many devices that have been developed for valve adjustment, valve deactivation, camshaft adjustment, etc. in conjunction with poppet valves can be adopted for the piston slide valves mentioned here without great development effort. For example, the bores for the bucket or hydraulic tappets of the poppet valves can also be used to accommodate the bucket tappets 47 of the piston slide valves mentioned here.The diameters of these bucket tappets 47, the valve springs 46, and the pistons 40 are selected so that they fit into a single through bore in the cylinder head 8, which offers significant manufacturing advantages. However, the stem can also be designed like conventional poppet valves with their longer guide and smaller diameter, allowing the use of the already known stem seals for better sealing. Furthermore, the lower part of the piston valve can also carry an additional piston ring 42a, thus also improving the seal against blow-by.

[0051] Further advantages of piston slide valves are that they do not require any adjustment for the valve clearance required for poppet valves, and as a result, no hydraulic tappets are needed. However, their simple shape makes them ideal for hydraulic, electric or pneumatic actuation. A further advantage is that they do not have to be circular, but the pistons can also have an elliptical or super-elliptical cross-section, for example. Pistons with a super-elliptical cross-section are already known and used successfully in motorcycles. This has shown that these pistons can be sealed well. However, they were probably too expensive to manufacture. The slide ways of the piston slide valves are much shorter and smaller and therefore easier to machine than those of the large pistons. This means that the inlet opening for the combustion air orThe fuel-air mixture and the exhaust outlet opening can be significantly expanded without the need for additional valves. The CNC machining centers currently in use are very precise, allowing the use of elliptical or superelliptical piston rings with sufficiently good sealing properties.

[0052] Fig. 4.C and 4.D show in the middle a piston valve in open position with piston 40, shaft 41, piston rings 42, 43, 44, shoulder 45 as spring holder or support, valve spring 46, bucket tappet 47, roller 48 with holder 49, half right ( Fig. 4.E) the piston valve body and on the far right ( Fig. 4.F) and on the far left ( Fig. 4.A) the valve in the closed position.

[0053] In Fig. 5.A is a section through the cylinder head 8 and the crankcase 9 of the engine block from the Fig. 1 at the location of cylinder 11. At the top is the camshaft 23 with the cam lobe 26, below is the shaft 22 for compression adjustment, then the roller 48 with holder 49 on the bucket tappet of the piston slide valve 7, further the working piston 12 with the piston pin 16 in cylinder 11 at the end of the connecting rod 15, which is mounted on the crankshaft 6. The crankshaft 6 in the crankcase 9 is shown in dashed lines for clarity, as it is not visible in the section. The cavities or cooling channels 79 and 80 as well as 91 and 92 serve to convey the coolant. However, piston slide valves have other advantages for increasing the power of internal combustion engines and reducing production costs. They can be controlled desmodromically much more easily than poppet valves. Fig. 5.B is an analogous cross-sectional view as in Fig. 5.A, but here the spring-operated piston valve 7 has been replaced by a piston valve 97 controlled desmodromically with the cam disc 85. In Fig. 5.C is the piston valve 97 and the cam disc 85 above in side view and in Fig. 5.D shown on the right as cross section AB.

[0054] The piston slide valve 97 carries two cam follower rollers 96 and 98 arranged one above the other on its upper side. The upper, smaller roller 96 rests and rolls in the groove 99 of the cam cam disc 85, and the lower, larger roller 98, with two lateral guide discs, rests and rolls on the underside of the cam cam disc 85. The lower roller 98 is larger than the upper roller 96 because it must withstand the high combustion pressure in the combustion chamber of cylinder 11 to which the valve 97 is exposed, while the upper roller 96 only has to pull the valve 97 upwards.

[0055] The valves 97 in the Fig. 5.B, 5.C, and 5.D are drawn in the length shown only for comparability with the spring-operated valve 7. It is clear that they can also be considerably shorter, so that desmodromically controlled piston valves, together with camshafts, can allow for very space-saving control of the intake and exhaust gases of internal combustion engines.

[0056] An advantageous object of the invention is the compression change by raising and lowering the camshaft 23. In Fig. 6. is a side view of the cylinder head 8 with the cylinder head cover 88 removed from Fig. 1. Shown is the adjustment slide 28 which is mounted on the side part 51 from the Fig. 1 is guided by four rollers 53 - 56 in lateral grooves 58, 59. The camshaft 23 is mounted on the adjustment slide 28 in a bearing 34. On the other side of the cylinder head 8, an analogous adjustment slide 27 is arranged, only mirror-inverted, on the side part 52 there and is also guided by rollers 60 - 63 in grooves 65, 66. The camshaft 23 is mounted there in a bearing 33. On the sides of the adjustment slides 27 and 28, toothed racks 67, 68 are attached, into which gears 71, 72 engage. These gears 71, 72 are attached in a rotationally symmetrical manner to the ends of a common shaft 22. The shaft 22 is rotatably mounted in the side parts 51 and 52. The side part 51 carries a hydraulic cylinder 29 on its upper side on an angle. This serves to adjust the angle of the shaft 22 and thus also of the gears 71, 72.A bell crank 21 is attached directly to the shaft 22 and serves to adjust the angle of the shaft 22 through a linear movement of the hydraulic piston 77, which is pivotally connected to the bell crank 21 via a joint 78. The resulting rotary movement of the gears 71 and 72 moves the racks 67 and 68, and thus also the adjustment slides 27 and 28, linearly up and down. The side parts 51 and 52 with the adjustment slides are each attached to the end faces of the cylinder head 8. The linear movement of the camshaft 23 also pushes the piston slide valves 3, 7, and 13, which rest against the cams 24, 25, and 26, up and down together. As a result, the piston undersides of the valves protrude further or less into the combustion chambers of cylinders 1 and 11 over pistons 2 and 12 and change the compression due to their additional volume or reduced volume.It is evident that the compression change by raising the camshaft 23 is also applicable in conventional internal combustion engines without transfer channels.

[0057] The exemplary embodiments presented so far showed internal combustion engines operating according to the four-stroke principle, which are not the subject of the invention. However, a significant proportion of internal combustion engines operate in two-stroke mode. Millions of smaller engines of this type, often single-cylinder, are particularly widespread in Asia. Even the largest internal combustion engines, marine diesel engines with the highest efficiency, and locomotive engines carry out a large part of the world's transport in two-stroke mode, where low costs are particularly important. Every percentage point of efficiency counts. Marine engines in particular often do not run at maximum load, but at part load for reasons of economy. Improving efficiency at part load, as is possible with compression adjustment and a second transfer cylinder, would mean significant cost savings here.

[0058] In the Fig. Figures 7.A and 7.B show a schematic diagram of an embodiment, depicting the state of a two-stroke internal combustion engine shortly after ignition in a side view. The piston valve 3 has been opened, allowing combustion gases to flow into the cylinder 11. As a result, the piston 12 moves downward due to the pressure of the combustion gases and exerts pressure on the crankshaft 6 via the connecting rod 15. Fig. 7.B below shows a section through cylinder 11 with piston 12 and connecting rod 15. Here, a counterweight 198 on the crankshaft 6 is shown slightly offset to the side for illustration and better overview, as are connecting rod 5 and counterweight 197 from cylinder 1. The actual power stroke takes place in cylinder 1. Shortly after ignition, high pressure acts on piston 2 in cylinder 1 alone, driving piston 2 downwards. This piston 2 also exerts a force on the crankshaft 6 via the connecting rod 5, creating a torque which, just as in cylinder 2, causes the crankshaft to rotate. When pistons 2 and 12 in cylinders 1 and 11 move down, the air in cylinders 1 and 11 is compressed beneath pistons 2 and 12 and in the crankcase 9.Shortly before the bottom dead center of piston 2, upon reaching the lower transfer ports 95 and 73, the path is clear for the fresh air from the crankcase to expel the burnt combustion gases upwards through these transfer ports 95 and 73 from the still open valve 3 into the neighboring cylinder 11. There, shortly before, approximately when the bottom dead center of piston 2 was reached, the exhaust valve 7 was also opened in order to release the combustion gases into the connecting port 14 or into the turbocharger 35. The two pistons 2 and 12 act in this example as charge pumps or piston scavenging pumps, which even at low speeds force sufficient fresh air from the crankcase 9 through the transfer ports 95 and 73 into the cylinder 1 next to the piston 2 into the space above the piston 2. There, they blow the exhaust gases through the transfer port 4 and the now open exhaust valve 7 into the connecting port 14 and then outwards and, for example,into the exhaust gas turbocharger 35. The volume of fresh air that is transported by the two pistons 2 and 12 through the transfer channels 95 and 73 is approximately twice as large as if only one piston were pumping the fresh air. This means that the exhaust gases can be completely blown out of cylinder 1, so that the part of the fresh air in the cylinder that is to be compressed can be free of exhaust gases. In many cases, however, this is not desired at all; instead, a part of the exhaust gases should remain in the cylinder, just as is done arbitrarily in four-stroke engines with exhaust gas recirculation in order to reduce nitrogen oxides and other harmful exhaust gases. The proportion of fresh air in cylinder 1 can therefore be influenced by suitable control of valve 3.In addition, due to the larger pumping volume of the two pistons 2 and 12 in relation to the compression volume of piston 2 alone, charging takes place, which allows an increase in power even at low speeds, in contrast to turbochargers, which only become effective at higher speeds. Since the scavenging of cylinder 1 with pistons 2 and 12 acting as charge pumps works right from the start from a standstill, no additional blowers such as Roots pumps are required, which fill the cylinders with fresh air in larger two-stroke diesel engines. The fresh air is sucked into the crankcase 9 through the valve 200. The counterweights 197 and 198 on the crankshaft are shaped so that they have as much volume as possible, filling most of the crankcase 9 so that there is not too much unused air there.As with most current two-stroke engines, fuel can be supplied via a fuel-air mixture through a carburetor, or by injection in gasoline engines and diesel engines. Lubrication in carburetor engines is typically provided by a fuel-oil mixture or an automatic fresh oil system, although some of the fuel mixture escapes into the atmosphere. A separate lubrication system with an oil reservoir separate from the fuel is more beneficial in terms of efficiency and pollutant emissions.

[0059] For example, a dry sump lubrication system like in a four-stroke engine can be used. Fuel injection is also advantageous, as it has long been used in both gasoline and diesel engines. Fig. 7, the camshaft 23 with the lifting device is attached to the side parts 51 and 52 and is movable in the same way as in Fig. 6, so that the piston valves 3 and 7 can be moved parallel to each other downwards or upwards and thus change the compression in the cylinders 1 and 11. The Fig. 7 show the plunger design of the engine as used for most smaller engines.

[0060] Another embodiment of the internal combustion engine with cylinder block 100 is shown in the Fig. 8.A and 8.B. The piston design with crosshead is used here, which is better suited for very large engines such as marine diesel engines. Therefore, a different air flow is used in this description than in the Fig. 7. This design also uses the underside of the pistons as charge pumps. However, not in connection with the crankcase 9, but only in cylinders 1 and 11 themselves. This is more beneficial for better lubrication of the crankshaft 6 and pistons 2 and 12, for achieving fewer pollutants in the exhaust gas itself, and for better efficiency. In this crosshead design, the long connecting rods 5 and 15 protrude straight from the underside of pistons 2 and 12 out of cylinders 1 and 11 and are connected to the crosshead 105 by a common mounting shaft 106. The crosshead 105 slides up and down in a straight line with the sliding block 103 on the plain bearing wall. It is connected to the connecting rod 104 with the crankshaft 6, with the counterweights 198 in Fig. 8.B in a side view and a section through cylinder 11 and crankcase 9. The numbers 91 and 92 designate cavities for liquid cooling, but air cooling is also possible. In this double-acting machine, the connecting rods 5 and 15 on the underside of cylinders 1 and 11 are guided into seals 102 at the end caps of cylinders 1 and 11. These seals seal the spaces below pistons 2 and 12 at the lower end of cylinders 1 and 11. This allows the lower sides of cylinders 1 and 11 to be used as a compression chamber and piston charge pump for fresh air, initially for intake via valve 200 and then further via valve 101 and finally for overflow through the transfer ports 95 and 73 into the combustion chamber in cylinder 1 above piston 2. This prevents oil splashing from the crankcase 9 from getting into cylinders 1 and 11 and possibly into the fresh air.Since the fresh air in the intake and compression chamber in cylinders 1 and 11 under pistons 12 and 2 together has a larger volume than the compression and combustion chamber above piston 2 in cylinder 1, charging occurs in cylinder 1 after this cylinder has been purged with the first part of the fresh air, when the exhaust valve 13 and the transfer valve 3 are closed again and the fresh air is compressed.

[0061] In the Fig. 8.A again shows the state after the end of the compression stroke at the beginning of a power stroke in cylinder 1. For this to happen, the piston slide valve 3 had to be opened again after ignition so that the combustion gases from cylinder 1 could flow through the transfer channel 4 with the guide web 94 into cylinder 11 above piston 12. The combustion gases then expand in both cylinders 1 and 11 and push pistons 2 and 12 downwards. Fresh air had previously flowed into cylinders 1 and 11 below pistons 2 and 12 through valve 200, which is now closed, and valve 101, which is now also compressed by the downward movement of pistons 2 and 12. This fresh air is then needed to scavenge only cylinder 1.The most advantageous method for very large two-stroke engines such as marine diesel engines in two-stroke operation, and also in our exemplary embodiment, is cocurrent scavenging in the longitudinal direction, with fresh air entering through the slots at the upper ends of the transfer channels 95 and 73 at the lower end of the first working cylinder 1 above the piston 2 when the piston 2 has reached bottom dead center, and the exhaust gases then exiting at the upper end of the cylinder 1 through a poppet valve or one or more piston slide valves 13. For scavenging, in our exemplary embodiment this piston slide valve 13 is opened and the transfer valve 3 to the adjacent cylinder 11 is closed so that no unwanted exhaust gases from cylinder 11 are forced into cylinder 1. The exhaust gases from cylinder 1 are then blown by the scavenging air from cylinder 1 via channels 4, 14 and 19 (exhaust path) into the turbocharger 35.After the exhaust gases have been purged from cylinder 1, the piston slide valve 13 is closed again so that the fresh air in cylinder 1 can be compressed. The exhaust gases from cylinder 11 are transported from the connecting channel 14 as well as 4 and 19 into the turbocharger 35 by the piston 12 rising via the piston slide valve 7, which opens after the piston 12 has reached bottom dead center. At the same time, the fresh air in cylinder 1 is compressed by the upward movement of the piston 2. Shortly before the piston 2 reaches top dead center, the fuel is injected into cylinder 1 and ignited in a gasoline engine, while it ignites itself in a diesel engine. Shortly thereafter, valve 7 is closed and valve 3 is opened to allow some of the combustion gases from cylinder 1 to flow into cylinder 11. This marks the beginning of the power stroke again, which can then be repeated as often as required.

[0062] The design chosen to simplify the crosshead 105 with a common fastening shaft 106 for connecting rods 5 and 15 can also be replaced by two separate crossheads. In this case, it is also possible for the crankshaft 6 to have two offset cranks, as is also the case in the Fig. 1, so that the piston 12 advances slightly over the piston 2, resulting in a more uniform torque distribution. The piston slide valves 13 and 7 can also be replaced by poppet valves. The dimensions of the drawing are for illustrative purposes only. The compression adjustment is also to be understood as Fig. 6. The remaining waste heat from the exhaust gases can be utilized, for example, on ships to preheat the fuel and heat the ship. Any excess power from the exhaust turbochargers can be used to drive electric motors, which provide a portion of the ship's electrical power. In combined heat and power plants, the heating power of the coolant is needed for the buildings, while any excess electrical power from the turbochargers can also be fed into the power grid. Piston purging is advantageous for emergency power generators because it takes effect immediately.

[0063] Advantageous embodiments and further developments of the internal combustion engine according to the invention will be described below.

[0064] Firstly, an internal combustion engine is conceivable with a crankcase 9 having a first cylinder 1, from which a connecting channel 4 in the cylinder head 8 leads to a second cylinder 11, via which air, fuel-air mixtures or combustion gases can flow after being controlled by a valve 3, wherein after ignition of a fuel-air mixture in the compression chamber of the first cylinder 1, the overflow valve 3 is opened, after which the combustion gases flow partially into the volume above the piston 12 in the cylinder 11, expanding and cooling down at the same time as the combustion gases in cylinder 1 during the power stroke, and due to the pressure on the upper piston surface of the piston 12, exerting a torque via the connecting rod 15 on the crankshaft 6 which is common to the pistons 2 and 12 and the connecting rods 5 and 15, and then after the bottom dead centre of the crankshaft 6 has been reached and the exhaust valve 7 in the cylinder head 8 has opened, the combustion gases which have cooled down after the power stroke are released into the second cylinder 11.Stroke by the upward movement of the pistons 2 and 12 via the valve 3 and the valve 7 are pushed out of the connecting channel 14, wherein after the exhaust valve 7 above the piston 12 has closed and after reaching the top dead center the inlet valve 13 to cylinder 1 is opened and air or fuel-air mixture is sucked into the cylinder 1 and then into the cylinder 11 by the downward movement of the pistons 2 and 12 in the 3rd, the intake stroke, which is then compressed after the valves 13 and 7 have closed in the 4th stroke in the compression chamber of the cylinder 1 by the upward movement of the pistons 2 and 12 and finally after the valve 3 closes near the top dead center the fuel-air mixture or in the case of an injection system after the injection of the fuel an ignition takes place in the compression chamber of the cylinder 1, after which the process just described is repeated.

[0065] Secondly, an internal combustion engine is conceivable with a crankcase 9 with a first cylinder 1, from which a connecting channel 4 in the cylinder head 8 leads to a second cylinder 11, via which air, fuel-air mixtures or combustion gases can flow after being controlled by a valve 3, and a third cylinder 81 to which a further connecting channel 14 with a further valve 93 leads from the middle cylinder 11, wherein after ignition of a fuel-air mixture in the compression chamber of the first cylinder 1, the overflow valve 3 is opened, after which the combustion gases flow partially into the volume above the piston 12 in the cylinder 11,expand and cool simultaneously with the combustion gases in cylinder 1 during the power stroke and exert a torque via the connecting rod 15 on the crankshaft 6 common to pistons 2 and 12 and connecting rods 5 and 15 due to the pressure on the upper piston surface of piston 12. After reaching the bottom dead center of the crankshaft 6 and opening the exhaust valve 7 in the cylinder head 8, the combustion gases cooled after the power stroke are expelled from the exhaust port 89 or exhaust by the upward movement of the pistons 2 and 12 via the valve 3 and the valve 7. After closing the exhaust valve 7 above the piston 12 and the overflow valve 3, after reaching the top dead center, the inlet valve 13 to cylinder 1 is opened and air or fuel-air mixture is sucked into the cylinder 1 by the downward movement of the piston 2 in the intake stroke.which are then compressed after the valve 13 closes in the compression chamber of cylinder 1 by the upward movement of the piston 2 and ultimately, near the top dead center of the piston 2, in the fuel-air mixture or, in the case of an injection system, after the fuel has been injected, an ignition takes place in the compression chamber of cylinder 1, whereby immediately after the cooled combustion gas is expelled from cylinder 11 via the exhaust valve 7, the latter is closed again and, after the ignition of a fuel-air mixture in the compression chamber of cylinder 81 has occurred in the meantime, the valve 93 is opened and the combustion gases from cylinder 81 pass through the connecting channel 14 and the valve 93 into the cylinder 11, there act on the piston 12 and execute a power stroke, after which the process just described is repeated.

[0066] Thirdly, an internal combustion engine is conceivable, whereby in a row, boxer, V, W, H, star or other arrangement, further transfer cylinders are added to adjacent cylinders as in the transition from the Fig. 1 to Fig. 2 to create larger machine units.

[0067] Fourthly, an internal combustion engine is conceivable, wherein the compression is changed by linearly raising or lowering the camshaft holder when using at least one piston slide valve per cylinder as closing elements or the compression is changed in other arrangements such as in the third mentioned arrangement by linearly raising and lowering the camshafts.

[0068] Fifthly, an internal combustion engine is conceivable, wherein the filling times in the cylinders 1 are changed by rotating the closing angle of the camshaft 23 relative to the crankshaft 6 or the closing angle is changed in other arrangements such as in the third mentioned arrangement by rotating the camshafts relative to the crankshafts.

[0069] Sixthly, an internal combustion engine is conceivable, whereby the separation of particulate matter and soot is carried out by an exhaust gas turbocharger with an associated centrifugal separator.

[0070] Seventhly, an internal combustion engine is conceivable in which the air or gas flow is converted from laminar flow into turbulent flow by turbulators or dimples, etc., so that the mixing of the fuel-air mixture is improved.

[0071] Eighthly, an internal combustion engine is conceivable in which the air or gas flow is converted by permeable obstacles in the air or gas flow in such a way that the mixing of the fuel-air mixture is improved.

[0072] Ninthly, an internal combustion engine is conceivable, in which injection channels are directed at such a short distance to the pistons or other components in the cylinders that they hit them and the fuel jets are thus atomized more finely.

[0073] Tenthly, an internal combustion engine with transfer channels is conceivable, with poppet valves being used to control the gas exchange.

[0074] Eleventhly, an internal combustion engine with transfer channels is conceivable, with piston slide valves being used to control the gas exchange.

[0075] Twelfthly, an internal combustion engine with transfer channels is conceivable, with poppet valves and piston slide valves being used to control the gas exchange.

[0076] Thirteenthly, an internal combustion engine without transfer channels is conceivable, with piston slide valves being used to control the gas exchange.

[0077] Fourteenthly, an internal combustion engine is conceivable, in which poppet valves and piston slide valves are used to control the gas exchange.

[0078] Fifteenthly, an internal combustion engine is conceivable with a crankcase 9 with a first cylinder 1, from which a connecting channel 4 in the cylinder head 8 leads to a second cylinder 11, over which air, fuel-air mixtures or combustion gases can flow after being controlled by a valve 3, wherein after ignition of a fuel-air mixture in the compression chamber of the first cylinder 1, the overflow valve 3 is opened, then the combustion gases partially flow into the volume above the piston 12 in the cylinder 11, expanding and cooling simultaneously with the combustion gases in the cylinder 1 during the power stroke, and exerting a torque via the connecting rod 15 on the crankshaft 6 common to the pistons 2 and 12 and the connecting rods 5 and 15 through the pressure on the upper piston surface of the piston 12, and then after reaching the bottom dead center of the crankshaft 6 and opening of the exhaust valve 7 in the cylinder head 8, the combustion gases cooled after the power stroke in the 2.Stroke are pushed out of the connecting channel 14 by the upward movement of the piston 12 in the cylinder 11 via the valve 7, whereby at the same time the exhaust gases from the cylinder 1 are conveyed by the fresh air or the fuel-air mixture from the crankcase 9 via the overflow channels 95 and 73 and the open valve 3 into the cylinder 11 and then via the connecting channel 14 into the turbocharger 35, the fresh air or the fuel-air mixture now contained in the compression chamber of the cylinder 1 is then compressed after the valves 13 and 7 close in the 2nd stroke in the compression chamber of the cylinder 1 by the upward movement of the pistons 2 and 12 and finally after the valve 3 closes near top dead center the fuel-air mixture or in the case of an injection system after the injection of the fuel an ignition takes place in the compression chamber of the cylinder 1, after which the process just described is repeated.

[0079] Sixteenthly, an internal combustion engine is conceivable with a crankcase 9 having a first cylinder 1, from which a connecting channel 4 in the cylinder head 8 leads to a second cylinder 11, over which air, fuel-air mixtures or combustion gases can flow after being controlled by a valve 3, wherein after ignition of a fuel-air mixture in the compression chamber and combustion chamber of the first cylinder 1, the overflow valve 3 is opened, after which a portion of the combustion gases flows into the volume above the piston 12 in the cylinder 11, expanding and cooling simultaneously with the combustion gases in the cylinder 1 during the power stroke, and exerting a linear force via the connecting rod 15 onto the fastening shaft 106 in the crosshead 105, which is common to the pistons 2 and 12 and the connecting rods 5 and 15, via the crosshead connecting rod 104 onto the crankshaft 6,thereby generating a torque on the crankshaft 6 and then, after reaching the bottom dead center of the crankshaft 6, closing the overflow valve 3 and opening the exhaust valve 7 in the cylinder head 8, the combustion gases cooled after the power stroke are expelled in the 2nd stroke by the upward movement of the piston 12 in the cylinder 11 via the valve 7 from the connecting channel 14 into the turbocharger 35, whereby at the same time the exhaust gases from the cylinder 1 above the piston 2 are flushed out by the fresh air or the fuel-air mixture that was sucked in through the valve 200 and the valve 101 below the pistons 2 and 12 into the cylinders 1 and 11, by being conveyed after the fresh air has been blown in via the overflow channels 95 and 73 and the exhaust gases from the cylinder 1 via the opened valve 3 and then via the channels 4 and 14 as well as the exhaust path 19 into the turbocharger 35 become,The fresh air or fuel-air mixture now contained in the compression and combustion chamber of cylinder 1 will then be compressed after the valves 13 and 7 close in the 2nd stroke in the compression and combustion chamber of cylinder 1 by the upward movement of pistons 2 and 12, and finally, after the valve 3 closes near top dead center, the fuel-air mixture or, in the case of an injection system, after the fuel is injected, an ignition will occur in the compression chamber of cylinder 1, after which the process just described is repeated.

[0080] Seventeenthly, an internal combustion engine is conceivable, wherein several arrangements, for example according to the fifteenth embodiment, are arranged in series to form a larger machine unit.

[0081] Eighteenthly, an internal combustion engine is conceivable, wherein several arrangements according to the sixteenth embodiment are arranged in series to form a larger machine unit.

[0082] Nineteenthly, an internal combustion engine is conceivable, in which valves for injecting and controlling compressed air for the purpose of starting the engine are provided according to the fifteenth to eighteenth embodiments.

[0083] In the twentieth place, an internal combustion engine is conceivable, in which valves for injecting and controlling compressed air are provided for the purpose of changing the direction of movement of the engine according to the fifteenth to nineteenth embodiment.

[0084] Twenty-first, an internal combustion engine is conceivable in which piston slide valves with elliptical or superelliptical cross-section are used for gas exchange and are sealed in matching elliptical or superelliptical guide bores with sealing elements made of elliptical or superelliptical piston rings.

[0085] Twenty-second, an internal combustion engine is conceivable, using hydrogen as a fuel. List of reference symbols 1 cylinder 2 pistons 3 valve 4 overflow channel 5 connecting rods 6 Crankshaft 7 Valve 8 cylinder head 9 Crankcase 11 cylinders 12 pistons 13 Valve 14 Linking channel 15 connecting rods 16 piston pins 17 Entrance 18 Valve 19 Outlet path 21 bell crank 22 Wave 23 Camshaft 24 cams 25 cams 26 cams 27 adjustment slides 28 adjustment slides 29 hydraulic cylinders 30 timing chain 31 gear 32 gear 33 camps 34 warehouses 35 turbochargers 36 Centrifugal separator 40 pistons 41 shaft 42 piston ring 42a piston ring 43 Piston ring 44 piston ring 45 paragraph 46 valve spring 47 bucket tappets 48 rolls 49 Bracket 50 snap ring 51 side panel 52 side panel 53 roll 54 roll 55 roll 56 roll 58 grooves 59 groove 60 rolls 61 roll 62 rolls 63 roll 65 groove 66 grooves 67 rack 68 rack 71 gear 72 gear 73 Overflow channel 74 groove 77 hydraulic pistons 78 joint 79 Cooling channel 80 cooling channel 81 cylinders 82 pistons 83 connecting rods 84 cams 85 Cam disc 86 cams 87 Entrance 88 cylinder head cover 89 Exhaust port 91 Cooling channel 92 cooling channel 93 Valve 94 Guide bridge 95 overflow channel 96 roll 97 Valve 98 roll 99 Nut 100 cylinder block 101 Valve 102 seals 103 sliding shoe 104 connecting rods 105 crossheads 106 Mounting shaft 197 Balance weight 198 balance weights 199 lids 200 valve

Claims

[1] Internal combustion engine for operation in two-stroke mode, comprising a first cylinder (1) defining a first combustion chamber, and a second cylinder (11) defining a transfer chamber, which are fluidically connected to one another via a transfer opening (4), a first piston (2) which is movable along a longitudinal axis of movement in the first cylinder (1) and a second piston (12) which is movable along a longitudinal axis of movement in the second cylinder (11), wherein the pistons are mechanically connected to one another by means of a crankshaft (6), a crankcase (9) in which the crankshaft (6) is arranged, a first valve (13) associated with the first cylinder (1), a second valve (7) associated with the second cylinder (11) and a third valve (3) associated with the transfer opening (4), wherein each of the valves (3, 7,13) is adjustable between an open position releasing a fluid path and a closed position closing this fluid path, wherein the internal combustion engine is designed to burn flammable liquids, such as diesel fuel, marine diesel oil, biodiesel, petrol, and / or two-stroke mixture, as well as flammable gases, such as hydrogen, LPG, natural gas and / or wood gas, characterized by a camshaft (23) which is designed to cooperate with at least one of the valves (3, 7, 13, 18, 93), and at least one lifting means (27, 28) which is designed to cooperate with the camshaft (23) in such a way that it is designed to change the distance of the camshaft (23) to at least one cylinder (1, 11, 81) in order to change the compression. [2] Internal combustion engine according to claim 1, characterized by that the first valve (13) is designed as an inlet valve and the second valve (7) as an outlet valve. [3] Internal combustion engine according to one of the preceding claims, characterized by that the crankshaft (6) has at least two throws and an advance of the second piston (12) before the first piston (2). [4] Internal combustion engine according to one of the preceding claims, characterized by that the second valve (7) is arranged and / or designed such that it fluidically connects the second cylinder (11) directly and the first cylinder (1) indirectly via the third valve (3) to a connecting channel (14). [5] Internal combustion engine according to one of the preceding claims, characterized bya third cylinder (81) defining a second combustion chamber, a third piston (82) movable along a longitudinal axis of movement in the third cylinder (81), the pistons (2, 12, 82) being mechanically connected to one another by means of the crankshaft (6), a connecting channel (14) via which the second cylinder (11) is fluidically connected to the third cylinder (81), a fourth valve (18) associated with the third cylinder (81) and a fifth valve (93) associated with the connecting channel (14), each of the valves (18, 93) being adjustable between an open and a closed position. [6] Internal combustion engine according to claim 5, characterized bythat it is designed such that after injection of fuel into the first cylinder (1) and before or with ignition of this fuel, the third valve (3) can be adjusted into its open position and / or that after injection of fuel into the third cylinder (81) and before or with ignition of this fuel, the fifth valve (93) can be adjusted into its open position. [7] Internal combustion engine according to one of the preceding claims, characterized by that one or more of the valves (3, 7, 13, 18, 93) are selected from the group comprising: poppet valve and piston slide valve. [8] A method for operating an internal combustion engine according to claim 1, in the two-stroke operating mode, wherein the internal combustion engine comprises at least: a first cylinder (1) defining a first combustion chamber, and a second cylinder (11) defining a transfer chamber, which are fluidically connected to one another via a transfer opening (4), a first piston (2) which is movable along a longitudinal axis of movement in the first cylinder (1) and a second piston (12) which is movable along a longitudinal axis of movement in the second cylinder (11), wherein the pistons are mechanically connected to one another by means of a crankshaft (6), a crankcase (9) in which the crankshaft (6) is arranged, a second valve (7) associated with the second cylinder (11) and a third valve (3) associated with the transfer opening (4), wherein each of the valves (3,7) is adjustable between an open position releasing a fluid path and a closed position closing this fluid path, comprising the following steps: 8.

1. Cycle 1:, 8.1.

1. Intake of a fluid-fuel mixture into the first cylinder (1), 8.1.

2. Moving the first piston (2) in its upward direction, thereby compressing the fluid-fuel mixture in the first cylinder (1), 8.1.

3. Moving the second piston (12) in its upward direction, thereby expelling exhaust gas from the second cylinder (11) via the second valve (7), 8.1.

4. Moving the third valve (3) to its closed position as soon as the second piston (12) has reached its top dead center, 8.1.

5. Suction of a fluid-fuel mixture into the crankcase (9) or a cylinder block (100), 8.1.

6. Ignition of the fluid-fuel mixture in the first cylinder (1) before the first piston (2) reaches its top dead center, 8.1.

7. Adjusting the third valve (3) to its open position, 8.1.

8. thereby overflowing the contents of the first cylinder (1) via the overflow opening (4) into the second cylinder (11), 8.

2. Stroke 2: 8.2.

1. Adjusting the first piston (2) in its downward direction, 8.2.

2. Adjusting the second piston (12) in its downward direction, 8.2.3 thereby compressing the fluid-fuel mixture in the crankcase (9) or the cylinder block (100), 8.2.

4. Directing the compressed fluid-fuel mixture from the crankcase (9) or the cylinder block (100) into the first cylinder (1) before the first piston (2) has reached its bottom dead center, 8.2.

5. thereby overflowing the burnt mixture from the first cylinder (1) via the overflow opening (4) through the second cylinder (11) into a connecting channel (14), and 8.2.

6. Adjust the third valve (3) to its closed position.

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