Internal combustion engine and methods for operating an internal combustion engine

Abstract

The present application relates to an internal combustion engine operating on the rotary principle, wherein at least one piston rotates on a circular piston path within an annular cylinder chamber bounded by a cylinder wall, passing through various zones of the cylinder chamber. On one full revolution of the internal combustion engine, corresponding to a complete rotation of the piston on its piston path (360°), an air-fuel mixture is ignited behind the piston in a combustion zone of the cylinder chamber. Later, during the same revolution, air located in front of the piston is compressed by the piston in a compression zone of the cylinder chamber. The compressed air is drawn into the piston and transported by the piston along its path into the combustion zone. There, the compressed air is discharged from the piston into the combustion zone and used to form the air-fuel mixture.

Description

[0001] The present application relates to an internal combustion engine according to claim 1. This internal combustion engine operates on the rotary principle, wherein at least one piston rotates on a circular piston path within an annular cylinder chamber bounded by a cylinder wall, thereby passing through various zones of the cylinder chamber. On one full revolution of the internal combustion engine, which corresponds to one full rotation of the piston on its piston path (360°), an air-fuel mixture is ignited in a combustion zone of the cylinder chamber behind the piston. Later, during the same revolution, air is compressed by the piston in a compression zone of the cylinder chamber located in front of the piston. The compressed air is drawn into the piston and transported by the piston along its path into the combustion zone.There, the compressed air from the piston is discharged into the combustion zone and used to form the air-fuel mixture. State of the art

[0002] The closest prior art is referenced to the two international patent applications WO 2021 / 029906 A1 and WO 2024 / 191587 A2. These disclose an internal combustion engine comprising a rotary compressor unit and a separate rotary combustion unit. The combustion unit is constructed such that it has a piston assembly with a piston carrier and a piston arranged thereon. The piston assembly is rotatably mounted about a piston carrier axis, allowing the piston to move along a circular piston path. The combustion unit further comprises a stationary cylinder assembly that interacts with the piston assembly and provides a cylinder wall that delimits an annular cylinder chamber. The cylinder assembly is arranged relative to the piston assembly such that the piston moves within the cylinder chamber.

[0003] To drive the piston, fuel and air are introduced into the cylinder behind the piston to form an air-fuel mixture and are ignited. The combustion of this mixture causes the expanding gases to displace the piston, thus driving it along its path. Through its connection to the piston carrier, the latter, and consequently the entire piston assembly, is also driven to rotate around the piston carrier axis. The generated torque is then transmitted via a torque-transmitting connection between the piston carrier and a piston carrier shaft.

[0004] The separate compressor unit is designed and configured to compress air so that this compressed air can be used in the combustion chamber to form the air-fuel mixture. The compressor unit also operates on the rotary principle, with a piston driven in a circular path and capable of compressing air located in front of it within the cylinder chamber of a cylinder unit belonging to the compressor unit. This compressed air can then be transferred, in sync with the piston's movement, into the cylinder chamber of the combustion chamber, where it is mixed with injected fuel and subsequently ignited.

[0005] To drive the piston in the combustion chamber due to the expansion of the hot gases after ignition of the air-fuel mixture, and to compress the air in the compressor, both components interact with a sealing device. These two sealing devices seal their respective cylinder chambers within a sealing zone in such a way that gases cannot escape. Each sealing device comprises a rotatable sealing element that projects into the cylinder chamber of its respective component, thereby sealing it. The sealing elements are operated synchronously with the combustion chamber and the compressor, respectively, so that the piston moves synchronously along its piston path to a recess in the sealing element and can enter the recess.This allows the piston to overcome the sealing element on every revolution.

[0006] In the combustion chamber, the sealing element forms the boundary of a combustion zone located behind the piston. This ensures that the hot gases produced by the ignition of the air-fuel mixture can only expand towards the piston, thus driving it. In the compressor, the sealing element forms the boundary of a compression zone where the air in front of the piston is trapped. As the piston moves towards the sealing element, the air is compressed. Before the piston passes over the sealing element, the compressed air is transferred from the compression zone into the combustion zone of the combustion chamber.

[0007] The conventional internal combustion engine has disadvantages in that its design is complex and the waste heat generated during operation is difficult to dissipate. Reliable, long-term operation of the internal combustion engine is therefore very difficult to achieve.

[0008] Document US 2,275,205 A discloses a rotary internal combustion engine in which a pulse wheel with two opposing cams (lobes) rotates within a housing. These cams cyclically engage corresponding recesses in rotating combustion chamber units, resulting in combustion within rotating chambers. Air is supplied by a fan rotating with the pulse wheel, which forces the air through a compressor wheel into the combustion chambers. Fuel is injected directly into the chambers through the cams via a central hollow shaft and injection tubes. Sealing between the cam and chamber is achieved through adapted geometry and adjustable sealing strips. The entire design is such that all moving parts—except for the injection system—rotate.

[0009] Document US 2,152,564 A discloses a rotary fluid engine in which an annular rotor with attached pistons rotates within a toroidal cylinder. Inside this cylinder are several rotatably mounted abutments (locking elements) with a radial recess, which mesh with the rotor via gears. The engine is driven by pressurized fluid such as steam, which is cyclically introduced through rotating inlet valves into the cylinder sections between the pistons and abutments, thus driving the pistons. The rotor's motion is transmitted via a central shaft. An internal lubrication system supplies all moving parts. All mechanical components, including the control elements, are housed within a common casing. Task

[0010] It is therefore the object of the present invention to provide a comparison to the prior art simplified internal combustion engine, the susceptibility of which to the temperature development caused by the operation of the internal combustion engine is lower. Solution

[0011] The underlying problem is solved according to the invention by means of an internal combustion engine with the features of claim 1. Advantageous embodiments are described in the dependent claims, the description and the exemplary embodiment.

[0012] The internal combustion engine comprises a combustion / compressor unit consisting of a piston assembly and a cylinder assembly. The piston assembly is rotatable about a piston carrier axis in one direction of rotation. The piston carrier axis can, for example, and preferably, be horizontally oriented. The piston assembly includes a piston carrier, which can, for example, and preferably, be annular or disc-shaped. Preferably, the piston carrier is rotationally symmetrical. Preferably, the center of gravity of the piston carrier lies on the piston carrier axis, so that the piston carrier can rotate freely about the piston carrier axis without imbalance. The piston carrier can, for example, be made of aluminum.

[0013] Furthermore, the piston unit comprises at least one piston rigidly connected to or arranged on the piston carrier. The piston projects radially outwards beyond the piston carrier, relative to an outer piston carrier radius, relative to the piston carrier axis. As detailed below, the piston unit preferably comprises at least two pistons, and more preferably exactly two pistons, arranged diametrically opposite each other on the piston carrier, relative to the piston carrier axis. During rotation of the piston unit about the piston carrier axis, both the piston carrier and the at least one piston arranged on it rotate about the piston carrier axis. In this process, the piston moves in the direction of rotation of the piston unit along a circular path around the piston carrier axis.Preferably, the piston is originally manufactured separately from the piston carrier and connected to the piston carrier by means of at least one connecting element or welded to the piston carrier. The piston is, for example, made of aluminum.

[0014] The piston encloses a cavity and has a piston opening through which air from outside the piston can enter and exit the cavity. Preferably, the piston opening extends radially with respect to the piston path along which the piston is movable. Preferably, one piston wall of the piston has a circular cross-section. Preferably, the piston is curved with respect to its central axis, more preferably in the form of a curved cylinder, wherein the curvature corresponds to the reciprocal of the radius of the piston path along which the piston moves about the piston carrier axis. In other words, the curvature of the cylinder preferably corresponds to a curvature of the piston path, such that the central axis of the piston and the piston path are arranged concentrically with respect to the piston carrier axis or overlap each other.If the piston is curved and cylindrical, the piston opening is preferably formed by a penetration of a piston wall of the piston, wherein the piston opening preferably penetrates the piston wall in a radial direction with respect to the central axis of the piston.

[0015] The cylinder unit is stationary and comprises a cylinder wall that spatially defines a cylinder chamber extending in an annular shape around the piston carrier axis. The cylinder wall can be formed in one piece or in multiple pieces. The cylinder chamber preferably has the shape of a torus, which is preferably radially slotted on the inside. The cylinder unit is arranged relative to the piston unit and its dimensions are matched to the piston unit such that the piston is located within the cylinder chamber and, during a rotational movement of the piston unit in the direction of rotation around the piston carrier axis, is movable along its circular piston path within the cylinder chamber. Accordingly, a central axis of the cylinder chamber extends around the piston carrier axis with a radius such that the piston is movable along its piston path within the cylinder wall in the direction of rotation of the piston unit.The radius of the cylinder's central axis is therefore larger than the piston carrier radius. The central axis of the cylinder and a circle defined by a radially outer edge of the piston carrier are arranged concentrically with respect to the piston carrier axis. If the piston's central axis is curved as described above, the piston's central axis and the cylinder's central axis are preferably arranged concentrically with respect to the piston carrier axis or overlap each other. The cylinder wall is preferably made of aluminum.

[0016] The piston and cylinder wall are designed to fit together in such a way that the piston, or rather its piston wall, is sealed against the cylinder wall. "Sealed" in this context means that neither a liquid nor a gas can flow past the piston from one side (i.e., between the piston, or its piston wall, and the cylinder wall). The piston itself also offers no flow path that would allow a liquid or gas to pass from its first side (the front side in the direction of rotation of the piston assembly) to its second side (the rear side in the direction of rotation of the piston assembly). Consequently, it is impossible for a liquid or gas to flow from the first side of the piston to its second side, or vice versa.

[0017] The cylinder wall has a plurality of wall openings, each penetrating the cylinder wall and thus suitable for establishing a fluid-flow connection between the cylinder chamber and an external area or a device connected to the cylinder wall. Preferably, the wall openings are oriented radially with respect to the central axis of the cylinder chamber. The wall openings are distributed in the cylinder wall in the circumferential direction of the cylinder chamber with respect to the piston carrier axis. The following description of the positions of the wall openings relative to each other refers to a full rotation (360°) of the piston assembly around the piston carrier axis, whereby the beginning of the rotation (0°) is defined as a position of the piston in which its leading edge reaches a combustion zone of the cylinder chamber as described below.

[0018] A first and a second wall opening are each assigned to a combustion zone within the cylinder chamber, extending over a portion of the cylinder's circumference. The combustion zone is designed for the ignition of an air-fuel mixture, which then combusts explosively, producing hot gases that expand rapidly. These gases exert pressure on the piston at its end face facing the combustion zone (the "rear" end in the direction of rotation of the piston assembly), thus driving the piston. This results in the piston moving along its path and consequently rotating the piston assembly around the piston carrier axis in the direction of rotation. Both liquid fuels (such as diesel or gasoline) and gaseous fuels (such as liquefied natural gas (LNG) or hydrogen) are suitable fuels.

[0019] The first wall opening is designed and configured to allow air or an air-fuel mixture to enter the cylinder chamber, specifically its combustion zone, from outside the cylinder. Whether air or an air-fuel mixture enters the combustion zone through the first wall opening during normal operation of the internal combustion engine depends on whether the air-fuel mixture is formed inside the cylinder chamber ("internal mixture formation") or outside the cylinder chamber ("external mixture formation"). Both are fundamentally possible. Internal mixture formation is preferred when using, for example, gasoline or hydrogen as fuel, while external mixture formation is preferred when using, for example, liquefied natural gas (LNG) as fuel.

[0020] The first wall opening is positioned in the cylinder wall in such a way that it does not overlap with the piston opening as the piston passes it. In other words, the positions of the first wall opening and the piston opening are aligned so that they move past each other without overlapping as the piston passes the first wall opening.

[0021] The second wall opening is located downstream of the first wall opening when viewed in the direction of rotation of the piston assembly. This means that, during normal operation of the internal combustion engine, the piston, moving along its circular path around the piston carrier axis in the direction of rotation of the piston assembly, reaches the combustion zone of the cylinder chamber before reaching the first wall opening and only then the second wall opening. The first and second wall openings are preferably arranged at an angular distance from each other, relative to the piston carrier axis, such that the piston has completely passed the first wall opening before reaching the second.For example, the angular distance between a center point of the first wall opening and a center point of the second wall opening, relative to the piston carrier axis, can be in a range between 10° and 30°, preferably between 15° and 25°.

[0022] The second wall opening is positioned within the cylinder wall and aligned with the piston opening such that, during normal operation of the internal combustion engine, the piston opening and the second wall opening (briefly) overlap as the piston moves along its path with each revolution. This overlap of the two openings occurs over a certain angular distance. The length of this angular distance, and thus the duration of the overlap, depends on the dimensions of the second wall opening and the piston opening, as well as the angular velocity of the piston along its path. One way to extend the duration of the overlap, while keeping all other operating parameters of the internal combustion engine the same, is to design the second wall opening as an elongated slot extending parallel to the piston path in the cylinder wall.Since the piston path describes a circle, the second wall opening in this embodiment preferably has a certain curvature along its long axis. The overlap of the piston opening with the second wall opening has the technical effect that air located in the piston cavity can escape through the piston opening and through the second wall opening to an external environment (outside the cylinder). In other words, a fluid-flow connection exists between the piston cavity and the external environment, allowing air to escape from the cavity (and thus from the cylinder). Preferably, the piston opening and the second wall opening are shaped identically. Preferably, the piston opening and the second wall opening are dimensioned identically.

[0023] The cylinder wall further comprises a third and a fourth wall opening, each corresponding to a compression zone extending over a partial circumference of the cylinder chamber. The compression zone is a separate zone of the cylinder chamber from the combustion zone, and the compression and combustion zones do not overlap. In other words, the compression zone extends over a partial circumference of the cylinder chamber that differs from the circumference over which the combustion zone extends. The compression zone is designed to compress air located in front of the piston (or a front face of the piston) when viewed in the direction of rotation of the piston assembly.The compression zone thus describes an area of ​​the cylinder space along which, as a result of the movement of the piston on its piston path, air located in front of the piston is compressed.

[0024] The third wall opening is designed and configured to allow air to escape from the cylinder chamber. For this purpose, the third wall opening is preferably located at the rear end of the compression zone, viewed in the direction of rotation of the piston assembly. As will be explained below, this achieves the effect that the air in front of the piston is only released from the compression zone through the third wall opening when the piston reaches the rear end of the compression zone and, consequently, the air in front of the piston has reached its maximum compression.

[0025] The third wall opening is positioned in the cylinder wall in such a way that, as the piston moves past it, it does not overlap with the piston opening. In other words, the positions of the third wall opening and the piston opening are aligned so that, as the piston passes the third wall opening, they move past each other without overlapping.

[0026] The fourth wall opening is located upstream of the third wall opening when viewed in the direction of rotation of the piston assembly. This means that, during normal operation of the internal combustion engine, the piston, as it moves along its piston path, first reaches the fourth wall opening before reaching the third wall opening during one revolution of the piston assembly around the piston carrier axis. The position of the fourth wall opening in the cylinder wall is aligned with the piston opening in such a way that, during normal operation of the internal combustion engine, the piston opening and the fourth wall opening (briefly) overlap during the piston's movement along its piston path for each revolution.This overlap means that air (preferably compressed air) can enter the piston cavity from outside the cylinder through the fourth wall opening and the piston opening. One way to extend the period of overlap between the piston opening and the fourth wall opening, while keeping the internal combustion engine's operating parameters otherwise the same, is to design the fourth wall opening as an elongated slot extending parallel to the piston path in the cylinder wall. Since the piston path describes a circle, the fourth wall opening in this design preferably has a certain curvature along its long axis. Preferably, the piston opening and the fourth wall opening are shaped identically. Preferably, the piston opening and the fourth wall opening are dimensioned identically.

[0027] Preferably, the third and fourth wall openings are arranged at an angular distance from each other, relative to the piston carrier axis, such that the piston, during its movement along the piston path, reaches the third wall opening before it has completely passed the fourth wall opening. A particularly advantageous embodiment is one in which the third and fourth wall openings are arranged at such an angular distance from each other, relative to the piston carrier axis, that the piston opening at the moment the piston reaches the third wall opening still overlaps at least partially with the fourth wall opening. Preferably, the angular distance between the third and fourth wall openings is in the range of 3° to 20°, more preferably between 5° and 15°.It is also conceivable that the third wall opening and the fourth wall opening are arranged relative to each other in such a way that the piston only reaches the third wall opening after the overlap between the piston opening and the fourth wall opening has ended.

[0028] The cylinder wall also features a fifth and a sixth wall opening, each of which – viewed in the direction of rotation of the piston assembly – is located downstream of the combustion zone, between the combustion zone and the compression zone (and thus upstream of the compression zone). Therefore, on one revolution of the piston assembly, the combustion zone is traversed first, followed by the sixth and fifth wall openings, and then, later still, the compression zone.

[0029] The fifth wall opening is designed and configured to allow an airflow, preferably in the form of a cooling airflow, to enter the cylinder chamber from outside during normal operation of the internal combustion engine. In a particularly preferred embodiment, the fifth wall opening can be fluidically connected to a compressor unit via a flow connection, which provides a cooling airflow during normal operation of the internal combustion engine. This is described separately below as an advantageous embodiment. During operation of the internal combustion engine, a (cooling) airflow introduced into the cylinder chamber through the fifth wall opening can ensure effective cooling of the combustion / compressor unit (especially its cylinder assembly).The fifth wall opening, like the other wall openings, penetrates the cylinder wall. This fifth wall opening establishes a fluid-flow connection between the cylinder chamber and the outside.

[0030] The sixth wall opening is designed and configured to allow exhaust gas to escape from the cylinder. Additionally, depending on the piston's position along its path, the sixth wall opening can also be used to expel a cooling airflow introduced into the cylinder through the fifth wall opening.

[0031] The sixth wall opening is located – viewed in the direction of rotation of the piston assembly – upstream of the fifth wall opening. In other words, the sixth wall opening is positioned relative to the fifth wall opening such that, during normal operation of the internal combustion engine, the piston, moving along its path, reaches the sixth wall opening before reaching the fifth wall opening in one revolution. It is conceivable that the fifth and sixth wall openings are arranged at an angular distance from each other, relative to the piston carrier axis, such that the piston, moving along its path, already at least partially covers the fifth wall opening before the sixth wall opening loses its contact with the piston.The angular distance between the fifth wall opening and the sixth wall opening, relative to the piston carrier axis, can be, for example, between 3° and 20°, preferably between 5° and 15°.

[0032] Preferably, both the fifth and sixth wall openings are positioned in the cylinder wall such that they do not overlap with the piston opening as the piston moves past them. In other words, the positions of the two wall openings and the piston opening are coordinated such that the piston opening and the two wall openings move past each other without overlap as the piston passes the two wall openings.

[0033] Viewed on a complete revolution of the piston assembly around the piston carrier axis, which, according to the above definition within the meaning of the present application, begins when the piston reaches the combustion zone with its front end wall or is located at the beginning of the combustion zone, the piston first passes the first wall opening and then the second wall opening. It then leaves the combustion zone.

[0034] Later in the same revolution, the piston, as it moves along the piston path, reaches the sixth wall opening and then the fifth. The sixth wall opening can, for example, be located at an angular distance from the second wall opening, measured relative to the piston carrier axis, with an angular distance between 70° and 110°, preferably between 80° and 100°. The angular position of the sixth wall opening relative to the piston carrier axis is preferably selected such that the piston thrust generated by the combustion of the air-fuel mixture is utilized to its maximum extent. This is the case as long as the combustion zone is sealed at its rear end and the hot gases produced as a result of combustion cannot escape from the combustion zone. This is explained separately below in connection with the sealing device.

[0035] The compression zone, located downstream of the fifth wall opening, begins, by definition, at the front end of the fifth wall opening in the direction of rotation of the piston assembly, as defined in the present application. This occurs when the piston, with its front end wall in the direction of rotation of the piston assembly, reaches this front end of the fifth wall opening, and the piston then completely covers the fifth wall opening. The air in front of the piston is trapped between the front end wall and a sealing element of the sealing device, as described below, and is successively compressed as the piston continues to move along its path. In other words, the piston reaches the compression zone from the point where it first completely covers the fifth wall opening, i.e., when its front end wall reaches the front end of the fifth wall opening.In other words, the compression zone begins "behind" the fifth wall opening. Upon reaching the compression zone, the piston then passes through the fourth wall opening and finally the third wall opening on the same revolution. The angular distance between the fifth and fourth wall openings can, for example, be between 70° and 110°, preferably between 80° and 100°. The angular position of the fifth wall opening relative to the piston carrier axis is preferably chosen such that an airflow can be introduced through the fifth wall opening into the cylinder until air compression can first occur in front of the piston. This is only possible when the compression zone is sealed at its front end and the air can no longer escape from the compression zone.This will be explained separately below in connection with the sealing device.

[0036] The piston completes a full revolution on its piston path when it re-enters the combustion zone. To do this, after leaving the compression zone, it must first overcome a sealing element or sealing zone described below. The complete revolution of the piston assembly is finished as soon as the piston re-enters the combustion zone.

[0037] When the piston, after ignition of the air-fuel mixture, moves from the combustion zone in the direction of rotation of the piston assembly—that is, along its piston path around the piston carrier axis—it consequently reaches the sixth wall opening on each revolution of the piston assembly before reaching the fifth wall opening. Once the piston has passed the sixth wall opening, it is fluidically connected to the section of the cylinder "behind" the piston, that is, the area of ​​the cylinder that extends behind the rear end wall of the piston when viewed in the direction of rotation of the piston assembly. In this area of ​​the cylinder, which encompasses the combustion zone, the hot gases produced from the combustion of the air-fuel mixture are located at this point.These gases can escape from the cylinder chamber through the sixth wall opening after the piston has passed it, initially only partially and eventually not at all. For example, and preferably, the internal combustion engine has an exhaust system ("exhaust") connected to the sixth wall opening on the outside of the cylinder wall, so that the gases, or an exhaust stream formed by these gases, can enter the exhaust system through the sixth wall opening and finally escape into the environment through the exhaust system.

[0038] At the moment when the piston, after passing the sixth wall opening, first opens it to the exhaust gas flow, the sixth wall opening is fluidically separated from the fifth wall opening. This is due to the piston, which is guided close to the cylinder wall, temporarily interrupting the fluid connection between the fifth wall opening (located downstream of the sixth) and the sixth wall opening. As long as this is the case, the exhaust gas flow can escape unhindered from the cylinder. The interruption of the fluid connection between the fifth and sixth wall openings only lasts until the piston has also passed the fifth wall opening.After the piston has passed the fifth wall opening, the flow connection between the fifth and sixth wall openings is reopened. For the operation of the internal combustion engine, this flow connection means that any (cooling) airflow introduced into the cylinder through the fifth wall opening can exit the cylinder through the sixth wall opening. Thus, the internal combustion engine can be operated advantageously in such a way that the cylinder is supplied with a cooling airflow through the fifth wall opening for a significant portion of a full piston revolution, thereby cooling the cylinder wall from the inside.If the piston is located on its path in a region upstream of the sixth wall opening or downstream of the fifth wall opening, a cooling airflow supplied to the cylinder via the fifth wall opening can escape into the environment through the sixth wall opening, thus creating a cooling airflow. Therefore, depending on the piston's position in the cylinder, the sixth wall opening serves either to discharge the exhaust gas flow or the cooling air flow from the cylinder.

[0039] The internal combustion engine further comprises a sealing device with a sealing element rotatable about a sealing element axis. This element is, for example, and preferably, annular or disc-shaped. Preferably, the center of gravity of the sealing element is located on the sealing element axis. The sealing element axis is oriented parallel to the piston carrier axis. For example, and preferably, both axes (piston carrier axis and sealing element axis) can be horizontally oriented.

[0040] The sealing element has a number of recesses corresponding to the number of pistons in the piston unit. These recesses are formed radially inward relative to the sealing element's axis and an outer radius. Thus, for example, the sealing element has exactly one such recess if the piston unit has exactly one piston, or exactly two such recesses if the piston unit has exactly two pistons, and so on. If the sealing element has a plurality of recesses, these are preferably distributed at equidistant angular intervals relative to the sealing element's axis. Therefore, in an exemplary embodiment of the sealing element with two recesses, these recesses are, for example, and preferably, arranged diametrically opposite each other relative to the sealing element's axis (the angular distance between the recesses relative to the sealing element's axis is then 180°).The sealing element, as explained below, is designed and configured to interact with the combustion / compressor unit in such a way as to seal the cylinder chamber in the area of ​​a sealing zone within the cylinder chamber. The recess in the sealing element allows the piston of the piston assembly to overcome the sealing element as it moves along its piston path. According to the following explanation of the internal combustion engine's operating principle, sealing the cylinder chamber by means of the sealing element is essential to prevent, firstly, the hot gases produced by the combustion of the air-fuel mixture from unintentionally escaping the combustion zone and thus driving the piston, and secondly, to prevent the air in the compression zone from unintentionally escaping and thus being compressed.

[0041] The internal combustion engine further comprises a piston carrier shaft connected to the piston carrier in a torque-transmitting manner and extending parallel to the piston carrier axis. The internal combustion engine also comprises a sealing element shaft connected to the sealing element in a torque-transmitting manner and oriented parallel to the piston carrier shaft, extending parallel to the sealing element axis. Through the torque-transmitting connection of the piston carrier shaft to the piston carrier (and thus to the piston assembly as a whole), a torque acting on the piston carrier by the drive of at least one piston can be dissipated via the piston carrier shaft and thus utilized. The coupling of the piston carrier shaft and the sealing element shaft is preferably designed such that the sealing element shaft is driven in a direction of rotation opposite to that of the piston carrier shaft.The direction of rotation of the piston carrier shaft corresponds to the drive direction of rotation of the piston unit, and the direction of rotation of the sealing element shaft corresponds to an opposite direction of rotation.

[0042] Furthermore, the internal combustion engine is designed such that the distance, measured perpendicular to the piston carrier axis, between the piston carrier axis and the sealing element axis is such that the sealing element projects into the cylinder chamber and is thus capable of sealing against the piston carrier and the cylinder wall. This results in the sealing element sealing the cylinder chamber in a sealing zone which—viewed in the direction of rotation of the piston assembly—is located downstream of the compression zone, between the combustion zone and the compression zone. For example, and preferably, the sealing zone, viewed in the direction of rotation of the piston assembly, adjoins the compression zone immediately and precedes the combustion zone. Preferably, the sealing zone extends over an angular range between 50° and 90° with respect to the piston carrier axis, more preferably between 60° and 80°.For the purposes of this application, the sealing zone is defined as the area of ​​the cylinder chamber over which the sealing element interacts with the cylinder wall to provide a seal. On a revolution of the piston assembly, which, as explained above, begins when the piston reaches the combustion zone, the sealing zone is the last area of ​​the cylinder chamber that the piston traverses before the revolution is completed.

[0043] The distance between the piston carrier axis and the sealing element axis is therefore matched to the sum of the piston carrier radius and the sealing element radius such that the sealing element and the piston carrier interact to create a seal at a contact point. At this contact point, the sealing element and the piston carrier can be in direct contact with each other, particularly along a contact line, which preferably extends in a plane perpendicular to both the piston carrier axis and the sealing element axis. The contact line can be straight or curved. The sealing element and the piston carrier come into sealing contact with each other at the contact point and thereby contribute to the sealing effect of the sealing element with respect to the cylinder chamber. At the contact point, the sealing element and the piston carrier can "roll" against each other.When the piston assembly rotates around the piston carrier axis in the direction of rotation during normal operation of the internal combustion engine, this means that the sealing element of the sealing device rotates around its sealing element axis in the opposite direction to the direction of rotation. In other words, the piston assembly and the sealing element rotate in opposite directions during operation of the internal combustion engine.

[0044] Preferably, the outer edges or surface areas of the piston carrier and the sealing element are designed to be complementary to each other, so that they can interact particularly well at the contact point to provide a seal, for example, and preferably by forming a contact line as described above. If, for example, an outer surface area of ​​the piston carrier is concavely curved, as described below as advantageous, it is advantageous if an outer surface area of ​​the sealing element is convexly curved and the curvatures of the surface areas are identical. With such a design, the sealing element can interact precisely with the piston carrier.

[0045] Since the cylinder wall of the cylinder unit is located at a greater radial distance from the piston carrier axis than the outer edge of the piston carrier, the sealing element projects into the cylinder chamber bounded by the cylinder wall. In addition to its contact with the piston carrier described above, the sealing element also acts as a seal with the cylinder wall at the common contact point. This has the effect of the sealing element sealing the cylinder chamber in the sealing zone. The cylinder wall is excluding the sealing element at this point, complementing the sealing element.

[0046] The tight interaction of the sealing element with the piston carrier and the cylinder wall, and the resulting sealing of the cylinder chamber in the sealing zone, means, within the meaning of the present application, that a direct flow of a fluid, i.e., a gas and / or a liquid, in the direction of rotation of the piston assembly from the compression zone to the combustion zone, or conversely, against the direction of rotation from the combustion zone to the compression zone, is prevented. Consequently, the sealing device, with its sealing element, ensures that, on the upstream side of the sealing zone, the compression of air in the compression zone can occur, and, on the downstream side of the sealing zone, namely in the combustion zone, the displacement and acceleration of the piston due to the combustion of the air-fuel mixture can take place.Thus, in the compression zone, the air between the piston and the sealing element is "trapped" and compressed as the piston moves along its path towards the sealing zone or the sealing element, starting from the point where it first fully covers the fifth wall opening. Immediately before the piston reaches the sealing element, the compression of the air trapped between the sealing element and the piston is at its maximum. As the piston continues its movement along its path, it must overcome the sealing zone, which it achieves via the recess in the sealing element, as explained below. On the other side of the sealing zone, or...The hot gases that form behind the piston at the moment of combustion of the air-fuel mixture can only expand in the direction of the piston and displace it, because in the direction opposite to the drive rotation of the piston unit the cylinder space is "blocked" by the sealing element and the gases therefore cannot escape in this direction.

[0047] In order for the piston to overcome the sealing element, the recess of the sealing element is designed and arranged on the sealing element in such a way as to be complementary to the piston, and the sealing element is aligned and arranged in such a way as to be complementary to the piston assembly, that during normal operation of the internal combustion engine, when moving along its piston path, the piston enters the recess of the sealing element upon reaching the sealing zone and can thus overcome the sealing zone from its side facing the compression zone to its side facing the combustion zone without collision in the direction of rotation of the piston assembly.Due to the counter-rotating motion of the sealing element, the recess moves with the piston as it continues along its path after reaching the sealing zone. To ensure that the piston assembly and the sealing element operate synchronously in such a way that the recess of the sealing element is available to the piston upon arrival at the sealing zone and then moves with the piston, the piston carrier shaft and the sealing element shaft are coupled to each other in a torque-transmitting manner. This coupling preferably has a gear ratio of 1:1.

[0048] The internal combustion engine further comprises a first flow connection that fluidically connects the first wall opening and the second wall opening. This first flow connection is thus capable of transferring air from the piston cavity into the combustion zone of the cylinder when, during the intended operation of the internal combustion engine, the piston is in a position along its piston path where the piston opening and the second wall opening overlap. In this process, the air from the piston cavity is guided behind the piston. For example, and preferably, the first flow connection is formed by a flow channel mounted on the outside of the cylinder wall and sealing tightly with the cylinder wall, which connects the outer surfaces of the first wall opening and the second wall opening.

[0049] Furthermore, the internal combustion engine comprises a second flow connection that fluidically connects the third and fourth wall openings. This second flow connection is designed to transfer air from the compression zone of the cylinder chamber into the piston cavity. This occurs when, during normal operation of the internal combustion engine, the piston is in a position along its piston path where the piston opening and the fourth wall opening overlap. For example, and preferably, the second flow connection is formed by a flow channel mounted on the outside of the cylinder wall and sealing tightly with the cylinder wall, connecting the outer surfaces of the third and fourth wall openings.

[0050] The operating principle of the internal combustion engine therefore stipulates that air located in the compression zone, between the front face of the piston (viewed in the direction of rotation of the piston assembly) and the sealing element, is compressed. The compression zone preferably extends over an angular range of at least 100°, preferably at least 110°, and more preferably at least 120° of the cylinder chamber relative to the piston carrier axis. Escape of the air located between the piston and the sealing element through the third or fourth wall opening arranged in the compression zone is not possible, since these two wall openings are connected to each other by means of the second flow connection. In this way, the second flow connection forms a self-contained volume outside the cylinder wall.Furthermore, escape at the end of the compression zone is impossible, as the cylinder chamber is sealed there, i.e., at the front end of the compression zone, by the sealing element. The compression zone therefore ends at the sealing element in the direction of rotation of the piston assembly.

[0051] When the piston finally reaches a position where its piston opening and the fourth wall opening overlap, the compressed air located between the piston and the sealing element can pass through the third wall opening into the second flow path, through this to the fourth wall opening, and finally through the piston opening into the piston cavity. Once the piston has moved further along its path until the piston opening and the fourth wall opening no longer overlap, the compressed air transferred into the cavity is "trapped" in the piston and can be transported by the piston.

[0052] With this compressed air, the piston, as it continues its movement along its piston path, overcomes the sealing zone downstream of the compression zone in conjunction with the sealing element and thus reaches the side of the sealing element facing away from the compression zone, namely the combustion zone downstream of the sealing zone. There, the piston moves past the first wall opening until it reaches a position where the piston opening and the second wall opening overlap. This causes the compressed air in the piston cavity to exit the piston through the overlapping openings and be guided by the first flow path to the first wall opening, from where it can re-enter the cylinder chamber, specifically its combustion zone.Since the first wall opening is located upstream of the second wall opening, this means that the compressed air, viewed in the direction of rotation of the piston assembly, is guided "behind" the piston. With preferred internal mixture formation, the air is used there (behind the piston) to form an air-fuel mixture, with fuel being introduced into the combustion zone in addition to the inflow of compressed air. This can be achieved, for example, and preferably, by means of an injection device described below. After the overlap between the piston opening and the second wall opening has been overcome, the formed air-fuel mixture is ignited, preferably by means of an ignition device described below, so that the air-fuel mixture is combusted explosively. This produces hot gases in a manner known per se, which spread out abruptly.Due to the sealing of the combustion zone by the sealing element in the direction opposite to the direction of rotation of the piston assembly, i.e., at the rear end of the combustion zone, these gases can only spread by "pushing" the piston away. In other words, the pressure generated by the hot gases in the combustion zone acts on the rear end face of the piston (when viewed in the direction of rotation of the piston assembly) and thus drives it to move along its piston path.

[0053] After all this, at the beginning of a revolution of the piston unit around the piston carrier axis, that is, in the combustion zone, the piston is first accelerated by burning an air-fuel mixture and then later on the same revolution is used for compression and taking in the air, which is used to form the air-fuel mixture in the next revolution.

[0054] The hot gases, or the resulting exhaust gas stream, are discharged via the sixth wall opening as described above. As explained above, this opening is preferably positioned so that the piston has passed the sixth wall opening, allowing the exhaust gas stream to escape from the cylinder chamber through it before a recess in the sealing element opens towards the rear end of the combustion zone. This is particularly advantageous in piston assembly configurations with at least two pistons.

[0055] Furthermore, in a preferred operating mode of the internal combustion engine, a cooling airflow can be continuously introduced into the cylinder wall via the fifth wall opening, cooling it from the inside. Depending on the cylinder's position along its piston path, the cooling airflow reaches different areas of the cylinder wall. Additional cooling of the cylinder assembly from the outside, i.e., on an outer surface of the cylinder wall, is also conceivable and advantageous. This is described separately below. As explained above, the fifth wall opening is preferably positioned such that the piston only completely covers the fifth wall opening when the compression zone is sealed at its front end, i.e., when a recess of the sealing element has passed the front end of the compression zone. This is particularly advantageous in configurations of the piston assembly with at least two pistons.

[0056] The internal combustion engine according to the invention has many advantages. In particular, it enables both combustion and compression using only one rotating unit, namely the piston assembly. In the prior art, different rotating devices are used for combustion and compression, as explained above. Accordingly, the internal combustion engine according to the invention has a simpler design compared to the prior art.

[0057] The way in which the air is compressed in the compression zone, transferred to the piston, carried along by the piston across the sealing zone into the combustion zone, and finally released into the combustion zone requires no external control, such as by means of valves or the like. Accordingly, the internal combustion engine is particularly robust and hardly prone to failure.

[0058] The absence of additional control elements, such as electrical components, also contributes to the efficiency of the internal combustion engine, since no mass reversal occurs at any point during normal operation, neither in the piston nor in any valves. Instead, the internal combustion engine consists solely of rotating masses that, during normal operation, move continuously in only one direction (piston assembly in the direction of rotation, sealing element in the opposite direction).

[0059] The possibility of continuously introducing a cooling airflow into the cylinder chamber via the fifth wall opening also allows the cylinder wall to be cooled particularly effectively.

[0060] In a preferred embodiment of the internal combustion engine, the combustion / compressor assembly and the sealing assembly are arranged relative to each other such that a piston carrier plane of the piston carrier, oriented perpendicular to the piston carrier axis and encompassing the piston path, and a sealing body plane of the sealing body, oriented perpendicular to the sealing body axis and containing the recess, are at least substantially congruent. In other words, in this embodiment, the piston carrier (with the at least one piston arranged thereon) and the sealing body extend in a common plane. In this embodiment, it is particularly advantageous if both the sealing body and the piston carrier are designed in the shape of a circular disk or annulus.

[0061] In a preferred embodiment of the internal combustion engine, the piston assembly comprises at least two pistons, preferably exactly two pistons. If the piston assembly comprises exactly two pistons, these are preferably arranged diametrically opposite each other on the piston carrier. In principle, in an embodiment of the internal combustion engine with multiple pistons, these are arranged on the piston carrier at equidistant angular intervals relative to each other, measured with respect to the piston carrier axis. Analogous to the embodiment of the piston assembly with only one piston, the pistons are arranged on the piston carrier such that, relative to the piston carrier axis, they project radially outwards beyond the piston carrier beyond the outer piston carrier radius. Preferably, all pistons are located together in a piston carrier plane oriented perpendicular to the piston carrier axis.In other words, the pistons are preferably not arranged offset from each other along the piston carrier axis. Preferably, all pistons are of identical design.

[0062] The design of the piston assembly with multiple pistons has the particular advantage that, with a suitable arrangement of the pistons relative to one another, the center of gravity of the piston assembly lies on the piston carrier axis, without the need for counterweights or similar devices. This, in turn, has the advantage that the piston assembly can be operated at least approximately, and preferably completely, free of vibrations during the intended operation of the internal combustion engine. This enables particularly gentle and robust operation of the internal combustion engine, as any material fatigue that can be caused by vibrations is avoided. As described above, the sealing element is always equipped with a number of recesses corresponding to the number of pistons, which are shaped in a manner complementary to the arrangement of the pistons in the sealing element.In this way, all pistons can always overcome the sealing zone by interacting with a corresponding recess in the sealing body.

[0063] Furthermore, the design of the piston assembly with multiple pistons has the advantage that the producible power of the internal combustion engine is increased compared to a design with only one piston. This is because, on each revolution of the piston assembly in the direction of rotation around the piston carrier axis, a number of combustion events corresponding to the number of pistons can take place. The design of the piston assembly with exactly two pistons initially proved to be the preferred variant, as this allows for sufficient compression of the air in the compression zone. With more than two pistons, the compression zone would have to be dimensioned "smaller" (with regard to the angular range over which the compression zone extends), which would result in a smaller absolute compression of the air within the compression zone.

[0064] In a preferred embodiment of the internal combustion engine, the piston carrier radius corresponds to the sealing element radius. In this embodiment, the piston carrier and the sealing element can roll against each other at their contact point without slippage. Furthermore, synchronizing the rotation of the sealing element and the piston assembly, which is necessary for the collision-free passage of the pistons through the sealing zone, is particularly easy to accomplish. This simply requires operating the piston carrier or piston assembly and the sealing element at the same rotational speed. This can be achieved particularly easily by means of a coupling of the piston carrier shaft to the sealing element shaft with a 1:1 gear ratio, as described above.

[0065] In a preferred embodiment of the internal combustion engine, the piston carrier shaft interacts with a first toothed disc, and the sealing element shaft interacts with a second toothed disc. Each of the two toothed discs has an outer tooth ring and is arranged relative to each other such that the tooth rings of the two toothed discs mesh. Thus, the two toothed discs extend in a common plane oriented perpendicular to both the piston carrier axis and the sealing element axis. The coupling of the piston carrier shaft to the sealing element shaft in the described manner is particularly simple and mechanically robust. Furthermore, in this embodiment, the two shafts (piston carrier shaft and sealing element shaft) are coupled without slippage, ensuring that the relative alignment of the sealing element to the piston assembly, which is necessary for synchronizing the recesses of the sealing element and the pistons of the piston assembly, is permanently maintained.

[0066] In a preferred embodiment of the internal combustion engine, the piston carrier shaft and the sealing element shaft are coupled to each other in such a way that a rotation of the piston carrier shaft can be transmitted to the sealing element shaft in a 1:1 gear ratio. This embodiment is particularly advantageous for the synchronous rotation of the sealing element about the sealing element axis and the piston assembly about the piston carrier axis.

[0067] In a preferred embodiment of the internal combustion engine, a radially outer edge surface of the piston carrier – viewed in a cross-section of the piston carrier parallel to the piston carrier axis – is concavely curved. This is particularly advantageous in combination with a further preferred embodiment of the internal combustion engine in which the cylinder wall is radially slotted on the inside relative to the piston carrier axis and its flanks facing the slot are in sealing contact with lateral contact surfaces of the piston carrier in a direction parallel to the piston carrier axis. During normal operation of the internal combustion engine and the associated rotation of the piston assembly in the direction of rotation about the piston carrier axis, a continuous relative motion takes place between the lateral contact surfaces of the piston carrier and the flanks of the cylinder wall.The cylinder wall is therefore dynamically sealed against the piston carrier at its flanks. For this purpose, sealing elements known per se can be arranged on the flanks of the cylinder wall and / or on the lateral contact surfaces of the piston carrier.

[0068] If the radially outer edge surface of the piston carrier is concavely curved and the cylinder wall is radially slotted on the inside, it is particularly advantageous if the cylinder wall – viewed in a cross-section parallel to the piston carrier axis – is arc-shaped between its flanks, with the piston carrier projecting into the slot of the cylinder wall in such a way that the concavely curved edge surface of the piston carrier completes an inner surface of the cylinder wall in the region of the slot, at least approximately, to form a full circle. In other words, in this embodiment, the curvature of the edge surface of the piston carrier is particularly favorably matched to the curvature of the inner surface of the cylinder wall, so that these curvatures coincide.This allows the piston carrier, with its outer surface, to effectively "bridge" the slot in the cylinder wall, so that, viewed in cross-section, the cylinder chamber is enclosed by a circular wall. This geometry is particularly advantageous with regard to unavoidable deformations of both the cylinder wall and the piston carrier that occur as a result of temperature effects during the continuous combustion processes of the internal combustion engine, since these deformations are distributed evenly over the inner circumference of the cylinder wall. The piston carrier deforms, at least approximately, in accordance with the cylinder wall as a result of such effects, thus ensuring reliable interaction between the cylinder wall and the piston carrier even during continuous operation of the internal combustion engine and the resulting high temperatures.

[0069] If the outer surface of the piston carrier is concavely curved, it is particularly advantageous if an outer surface of the sealing element is complementarily convexly curved. This has already been described above as an exemplary embodiment.

[0070] In an advantageous embodiment of the internal combustion engine, the cylinder wall, the piston carrier, and all pistons are made of the same material. This ensures that the thermal expansion of these components is always uniform. Preferably, all of these components are made of aluminum.

[0071] In a preferred embodiment of the internal combustion engine, it comprises a compressor unit, preferably in the form of a turbo compressor (also referred to in the technical language as a "turbocharger"). Furthermore, in this embodiment, the internal combustion engine includes a third flow connection. The compressor unit is coupled to the piston carrier shaft or the sealing element shaft and can be driven by a rotary motion of the respective shaft. The compressor unit is designed and configured to draw in air from the environment and compress it. The compressed air is introduced into the cylinder chamber via the third flow connection. For this purpose, the third flow connection is fluidically connected at one end to the compressor unit and at the other end to the cylinder wall, with the third flow connection fluidly interacting with the fifth wall opening.In this way, the air compressed by the compressor device can be introduced into the cylinder chamber via the third flow connection through the fifth wall opening.

[0072] Due to the coupling of the compressor assembly with the piston carrier shaft or the sealing element shaft, the compressor assembly operates continuously when the internal combustion engine is running, that is, when the piston assembly is driven around the piston carrier axis. Consequently, a continuous volume flow of compressed air is available via the compressor assembly during operation of the internal combustion engine, which can be introduced into the cylinder chamber via the third flow connection. This volume flow is particularly well suited for use as, or constitutes, the cooling air flow described above. If the compressor assembly is a turbo compressor, it is particularly advantageous if the compressor blades are mounted directly onto the piston carrier shaft or the sealing element shaft.It is also conceivable that the impeller blades are mounted on a separate compressor shaft, which is connected to the carrier shaft or the sealing element shaft in a torque-transmitting manner, for example via a toothed disc as described above. Such a design can also be seen in the following exemplary embodiment.

[0073] In a preferred embodiment of the internal combustion engine, it comprises an ignition device arranged in or on a section of the cylinder wall associated with the combustion zone of the cylinder chamber. The ignition device is designed and configured to ignite the air-fuel mixture located in the combustion zone. This is typically achieved by means of a spark, which can, for example, be electronically synchronized to the movement of the piston along its piston path. In principle, operation of the internal combustion engine as a compression-ignition engine, i.e., without a separate ignition device, is also conceivable.

[0074] In a preferred embodiment of the internal combustion engine, it comprises an injection device, which is preferably arranged in or on a section of the cylinder wall associated with the combustion zone. The injection device is designed and configured to inject fuel, preferably directly into the combustion zone (in the case of internal mixture formation).

[0075] It is also conceivable that the air-fuel mixture is formed outside the cylinder chamber, for example, in a mixing chamber located outside the cylinder chamber. In this configuration, the mixing chamber forms a section of the first flow path, which, as explained above, fluidically connects the second wall opening and the first wall opening. The compressed air, drawn from the piston cavity and transferred into the combustion zone via the first flow path, flows through the mixing chamber in this configuration, into which the fuel is injected at a precise time. Accordingly, in this configuration, the respective injection device is arranged in or on a wall of the mixing chamber. Upon entering the combustion zone, the air is therefore already mixed with the fuel, so that a complete air-fuel mixture enters the combustion zone.

[0076] In a preferred embodiment of the internal combustion engine, it includes a cooling device that interacts with an outer surface of the cylinder wall and is designed and configured to dissipate waste heat acting on the cylinder wall. Preferably, the cooling device is designed as a liquid cooling system. Such a cooling device can support the "internal cooling" achieved by the continuous supply of cooling air into the cylinder chamber during operation of the internal combustion engine. The cooling device can otherwise be designed in a manner known per se.

[0077] From a process engineering perspective, the underlying problem is solved by means of a method with the features of claim 14. Advantageous embodiments are described in the associated dependent claim, the description, and the exemplary embodiment.

[0078] The process involves a piston rotating on a circular path within an annular cylinder. In a compression zone extending over a portion of the cylinder's circumference, the piston compresses air located in front of it. This compressed air is then transferred into a cavity within the piston. Loaded with the compressed air, the piston, as it continues its movement along its path, passes through a sealing zone and enters a combustion zone extending over another portion of the cylinder's circumference. Within the combustion zone, the compressed air from the piston's cavity is drawn into the cylinder behind the piston and used to form an air-fuel mixture.This air-fuel mixture is ignited, whereupon it burns explosively, driving the piston along its piston path.

[0079] The method according to the invention is particularly easy to carry out using the internal combustion engine according to the invention. The advantages are correspondingly similar. The procedures for operating the internal combustion engine described above are also advantageous for the method according to the invention.

[0080] In a preferred embodiment of the method, the piston enters a recess of a rotary-driven sealing element from the compression zone to overcome the sealing zone and, upon further movement along its piston path towards the combustion zone, exits the recess again, with the sealing element otherwise sealing the cylinder space in the sealing zone. Examples of implementation

[0081] The invention is explained in more detail below with reference to an exemplary embodiment shown in the figures. These show: Fig. 1: A front view of an internal combustion engine according to the invention, Fig. 2: The view according to Fig. 1, where components enclosed in the internal combustion engine are illustrated, Fig. 3: A cross-section through the internal combustion engine parallel to a piston carrier axis according to Fig. 1, Fig. 4: A detail of a piston arranged in a cylinder chamber, Fig. 5: A detail of the cylinder space according to Fig. 4, Fig. 6: A schematic representation of a sealing body housing and a cylinder wall of the internal combustion engine according to Fig. 1, Fig. 7: A front view of the sealing body housing and the cylinder wall according to Fig. 6, Fig. 8: The front view of the internal combustion engine, showing a piston unit at the beginning of a revolution, where a first piston of the piston unit reaches a combustion zone of the cylinder wall (0°), Fig. 9: The front view according to Fig. 8, wherein the piston assembly is in such a position that a piston opening of the first piston overlaps with a second wall opening of the cylinder wall (38°), Fig. 10: The front view according to Fig. 8, wherein the piston assembly is in such a position that a piston opening of the first piston and a second wall opening of the cylinder wall no longer overlap (42°), Fig. 11: The front view according to Fig. 8, wherein the piston assembly is in such a position that the first piston has just passed a sixth wall opening of the cylinder wall (147°), Fig. 12: The front view according to Fig. 8, wherein the piston assembly is in such a position that the first piston just overlaps a fifth wall opening of the cylinder wall (180°), Fig. 13: The front view according to Fig. 8, wherein the piston assembly is in such a position that the first piston has just passed the fifth wall opening of the cylinder wall (211°), Fig. 14: The front view according to Fig. 8, wherein the piston assembly is in such a position that the piston opening of the first piston overlaps with a fourth wall opening of the cylinder wall (284°), Fig. 15: The front view according to Fig. 8, wherein the piston assembly is in such a position that the piston opening of the first piston and the fourth wall opening of the cylinder wall no longer overlap (289°), Fig. 16: The front view according to Fig. 8, wherein the piston assembly is in such a position that the first piston is located centrally in a sealing zone of the cylinder chamber (341°).

[0082] One embodiment, which is described in the Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7, Fig. 8, Fig. 9, Fig. 10, Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15 to Fig. Figure 16 shows a combustion engine 1 according to the invention, which operates on the rotational principle. The combustion engine 1 comprises a combustion / compressor unit 2, a sealing unit 25, a piston carrier shaft 32, a sealing element shaft 33, a first flow connection 34 and a second flow connection 35.

[0083] The combustion / compressor unit 2 comprises a piston assembly 4 and a cylinder assembly 12. The piston assembly 4 is rotatable in a drive direction 62 about a piston carrier axis 3. In the figures shown, this drive direction 62 of the piston assembly 4 always corresponds to clockwise rotation. The piston assembly 4 comprises a piston carrier 5 and two pistons 7, 8 rigidly connected to the piston carrier 5. The piston carrier 5 is preferably annular in shape, with the center point of the annulus formed by the piston carrier 5 lying on the piston carrier axis 3. The pistons 7, 8 are arranged diametrically opposite each other on the piston carrier 5. For this purpose, the pistons 7, 8 are connected to the piston carrier 5 at an outer edge 51. This connection can be formed, for example, by means of fasteners. The pistons 7, 8 can also be welded to the piston carrier 5.

[0084] The pistons 7, 8 project radially outwards beyond the piston carrier 5 relative to the piston carrier axis 3 and an outer piston carrier radius 6. The center of gravity of the piston unit 4 is located here, and preferably on the piston carrier axis 3. As a result, during a rotational movement of the piston unit 4 in the direction of rotation 62 about the piston carrier axis 3, the pistons 7, 8 are moved along a circular piston path whose center lies on the piston carrier axis 3. Thus, the piston path and the outer edge 51 of the piston carrier 5 are arranged concentrically with respect to each other, with the piston path extending further radially outwards relative to the piston carrier axis 3, or having a larger path radius, than the outer edge 51, which extends around the piston carrier axis 3 within the piston carrier radius 6. The piston path and a circle described by the outer edge 51 of the piston carrier 5 are arranged concentrically with respect to each other.Both the piston carrier 5 and the associated pistons 7, 8 are here and preferably each made of aluminium.

[0085] The pistons 7 and 8 are formed here, and preferably, by curved cylinders. This is particularly evident from the following: Fig. 2. Thus, the pistons 7, 8 each have a curved central axis 52, the curvature of which corresponds to a curvature of the piston path. This curvature is therefore the reciprocal of the path radius of the piston path with respect to the piston carrier axis 3. The pistons 7, 8 each enclose a cavity 10, which, viewed in the direction of the piston path, is spatially enclosed at the opposite ends of the respective piston 7, 8 by end walls 53, 54 and between the end walls 53, 54 by a piston wall 55. This piston wall 55 preferably has the form of a curved cylinder wall. The pistons 7, 8 also each have a piston opening 11, which is provided in the piston wall 55 of the respective piston 7, 8 and extends in a radial direction with respect to the piston path or the central axis 52 of the respective piston 7, 8.The piston opening 11 serves to establish a flow-related connection between the cavity 10 and an area outside the respective piston 7, 8. In other words, the piston opening 11 is designed and configured to allow air from outside the piston 7, 8 to enter the cavity 10 and exit it again. The pistons 7, 8 are preferably identical in design.

[0086] The cylinder unit 12 of the combustion / compressor assembly 2 has a cylinder wall 13 that spatially defines a cylinder chamber 14 extending in an annular shape around the piston carrier axis 3. In the example shown, the cylinder wall 13 is formed in two parts, namely a first half-shell 56 and a second half-shell 57. The two half-shells 56, 57 each form corresponding recesses on their facing surfaces, which, when joined together in a direction parallel to the piston carrier axis 3, together form the cylinder chamber 14. In the example shown, the recesses in the two half-shells 56, 57 are shaped in such a way as to form semi-circular rings that the cylinder chamber 14 has a circular cross-section when viewed in a cross-section parallel to the piston carrier axis 3.This results in an inner lateral surface 50 of the cylinder wall 13, which bounds the cylinder chamber 14, having the shape of a circular arc when viewed in the aforementioned cross-section. This is particularly evident from the... Fig. 4 and Fig. 5. It should be noted that the two half-shells 56, 57 do not form a completely sealed ("tight") cylinder chamber 14; that is, the cylinder wall 13 formed by the half-shells 56, 57 does not, on its own, seal the cylinder chamber 14 from the environment. This sealing of the cylinder chamber 14 only occurs through the interaction of the cylinder unit 12 with the piston unit 4. The half-shells 56, 57 are preferably each made of aluminum. They are connected to each other by means of a plurality of connecting elements 63.

[0087] The cylinder unit 12 is arranged relative to the piston unit 4 and its dimensions are matched to the piston unit 4 such that the pistons 7, 8 are located within the cylinder chamber 14. This is particularly evident from the Fig. 2, Fig. 3 to Fig. 4. The cylinder wall 13 has a slot 47 on its radially inner side (facing the piston carrier axis 3), into which the piston carrier 5 is precisely inserted or in which the piston carrier 5 is precisely received. The cylinder chamber 14 is spatially enclosed by the interaction of the cylinder wall 13 and the piston carrier 5. Thus, the inner wall surface of the cylinder chamber 14 is formed largely by the inner surface 50 of the cylinder wall 13 and partly by an outer surface 46 of the piston carrier 5.

[0088] To ensure that the cylinder chamber 14 is tightly sealed from the environment, opposing flanks 48 of the cylinder wall 13 rest against lateral contact surfaces 49 of the piston carrier 5. Since the piston carrier 5, or the entire piston assembly 4, rotates about the piston carrier axis 3 during the intended operation of the internal combustion engine 1, while the cylinder wall 13 remains stationary, the flanks 48 of the cylinder wall 13 and the lateral contact surfaces 49 of the piston carrier 5 continuously slide against each other. For improved sealing, gaskets (not shown in the figures) are installed at this point; these gaskets can be designed in a manner known per se.

[0089] An outer edge surface 46 of the piston carrier 5 is preferably concavely curved. This is particularly evident from the Fig. 4 and Fig. 5. This design has the advantage that the outer edge surface 46 of the piston carrier 5 meets the inner surface 50 of the cylinder wall 13, which here and preferably between the flanks 48 is formed in a circular arc shape, in that the Fig. 4 and Fig. The cross-section shown in Figure 5 is at least approximately completed to form a full circle. For this purpose, the curvature of the outer edge surface 46 is adapted to the curvature of the inner surface 50 of the cylinder wall 13, so that these curvatures are at least substantially identical. This design has the advantage that deformations of the cylinder wall 13 and the piston carrier 5 resulting from temperature effects are at least substantially identical.

[0090] The pistons 7, 8, which project radially outwards beyond the piston carrier radius 6 and beyond the outer edge 51 of the piston carrier 5, extend radially from the outer edge 51, relative to the piston carrier axis 3, into the cylinder chamber 14. There, they are arranged such that, during a rotational movement of the piston unit 4 in the direction of rotation 62 about the piston carrier axis 3, they are movable along the circular piston path within the cylinder chamber 14. A central axis 64 of the cylinder chamber 14, which extends circularly around the piston carrier axis 3, is here, and preferably, coincident with the piston path of the pistons 7, 8 or their central axes 52.

[0091] As can be seen in particular from the Fig. 3 and Fig. As shown in Figure 4, the pistons 7 and 8 are dimensionally adapted to the cylinder wall 13 such that they fit precisely into the cylinder chamber 14. This results in the pistons 7 and 8 being sealed against the cylinder wall 13. A flow of liquid or gas from one side of each piston 7 or 8 in the area between the inner surface 50 of the cylinder wall 13 and an outer surface of the piston wall 55 to the opposite side of the piston 7 or 8 is therefore impossible. In this way, the two pistons 7 and 8 divide the cylinder chamber 14 into fluidically separated areas. Depending on the position of the pistons 7 and 8 relative to a sealing element 27 of the sealing device 25, which is described separately below, the cylinder chamber 14 is divided into either two or three fluidically separated areas in the example shown. This is particularly evident from the following: Fig. 8, Fig. 9, Fig. 10, Fig. 11, Fig. 12, Fig. 13, Fig. 14, Fig. 15 to Fig. Figure 16 illustrates the movement of the piston unit 4 during one full revolution in the drive direction 62 about the piston carrier axis 3. By definition, for the purposes of this application, the revolution begins when the first of the two pistons 7, 8 is in a position where it just enters a combustion zone 21 of the cylinder chamber as described below (see Figure 16). Fig. 8).

[0092] The cylinder wall 13 has a total of six wall openings 15, 16, 17, 18, 19, 20, each of which penetrates the cylinder wall 13 and is thus suitable for establishing a fluid-flow connection between the cylinder chamber 14 and an external area 23 outside the cylinder wall 13. The wall openings 15, 16, 17, 18, 19, 20 penetrate the cylinder wall 13 here and preferably in a radial direction with respect to the central axis 64 of the cylinder chamber 14.

[0093] A first wall opening 15 and a second wall opening 16 of the cylinder wall 13 are jointly assigned to the combustion zone 21 of the cylinder chamber 14. The combustion zone 21 describes a section of the cylinder chamber 14 extending over a partial circumference, which is associated with the combustion of an air-fuel mixture and the resulting acceleration of a respective piston 7, 8. The first wall opening 15 is designed and configured to allow air to enter the combustion zone 21 from outside the cylinder chamber 14 through the first wall opening 15.During operation of the internal combustion engine 1, fuel is injected into the combustion zone 21 by means of an injection device 44 arranged in the cylinder wall 13, in temporal connection with the introduction of air through the first wall opening 15 into the combustion zone 21, so that the fuel and the air mix together in the combustion zone 21 to form the air-fuel mixture. This mixture is then ignited by means of an ignition device 43, also arranged in the cylinder wall 13, so that the air-fuel mixture burns explosively.

[0094] The second wall opening 16, which is also associated with the combustion zone 21, is located downstream of the first wall opening 15 in the cylinder wall 13 when viewed in the direction of rotation 62 of the piston assembly 4. Here, and preferably, the angular distance between the first wall opening 15 and the second wall opening 16, measured with respect to the piston carrier axis 3, is approximately 20° (measured between the centers of the wall openings). In other words, the second wall opening 16 is located just downstream of the first wall opening 15 when viewed on the circumference of the cylinder chamber 14. Unlike the first wall opening 15, the position of the second wall opening 16 in the cylinder wall 13 is aligned with the piston openings 11.This alignment consists in the fact that, during the intended operation of the internal combustion engine 1, when a respective piston 7, 8 passes the second wall opening 16, the piston openings 11 and the second wall opening 16 temporarily overlap in such a way that air located in the cavity 10 of the piston 7, 8 can escape through the piston opening 11 from the cavity 10 of the piston 7, 8 and through the second wall opening 16 from the cylinder chamber 14 (see . Fig. 9) In contrast, the first wall opening 15 is positioned in the cylinder wall 13 such that the piston opening 11 and the first wall opening 15 do not overlap when a piston 7, 8 passes the first wall opening 15; that is, no fluid-flow connection is established between the cavity 10 and the outer surface of the cylinder wall 13 through the first wall opening 15. The second wall opening 16 can also be designed as an elongated slot, unlike the one shown in the figures, so that the overlap of the second wall opening 16 with the piston opening 11 lasts longer as the piston 7, 8 moves past the second wall opening 16 than with a "round" second wall opening 16, as shown in the figures.

[0095] The first wall opening 15 and the second wall opening 16 are fluidically connected to each other by means of the first flow connection 34. Here, and preferably, the first flow connection 34 is formed by a flow channel placed on an outer surface of the cylinder wall 13. This is particularly well illustrated by Fig. 7. The first flow connection 34 therefore allows compressed air, which is held in the cavity 10 of a respective piston 7, 8, to pass from the second wall opening 16 to the first wall opening 15 and thus into the combustion zone 21. Since the first wall opening 15 is located upstream of the second wall opening 16, the compressed air stored in the respective piston 7, 8 or its cavity 10 is consequently directed behind the piston 7, 8 via the first flow connection 34 during the intended operation of the internal combustion engine 1. There it is then available for the formation of the air-fuel mixture as described above. As a result of the combustion of this mixture as described above, the respective piston 7, 8 is then displaced by the hot gases that form, and thereby the piston unit 4 is driven in the direction of rotation 62 around the piston carrier axis 3.

[0096] The cylinder wall 13 further comprises a third wall opening 17 and a fourth wall opening 18, each of which also penetrates the cylinder wall 13. The third wall opening 17 and the fourth wall opening 18 are each assigned to a compression zone 22 of the cylinder chamber 14. Similar to the combustion zone 21 described above, the compression zone 22 also forms a section of the cylinder chamber 14 extending over an angular range relative to the piston carrier axis 3. The compression zone 22 and the combustion zone 21 are spatially defined as separate areas of the cylinder chamber 14. Functionally, the compression zone 22 is characterized by the fact that air is compressed within it.The compressed air is introduced into the cavity 10 of the respective piston 7, 8 according to the mechanism described below and is “carried away” by means of the piston 7, 8 for use in the combustion zone 21 for the next combustion.

[0097] The third wall opening 17 of the cylinder wall 13 is designed and configured to allow air to escape from the cylinder chamber 14 (more precisely: from the compression zone 22) into the external area 23 through the third wall opening 17. The third wall opening 17 is positioned in the cylinder wall 13 such that it does not overlap with the piston opening 11 of a piston 7, 8 as it passes by, thus preventing the formation of a flow-related connection between the cavity 10 of the respective piston 7, 8 and the external area 23 at this point.

[0098] The situation is different with the fourth wall opening 18, which, viewed in the direction of rotation 62 of the piston assembly 4, is located upstream of the third wall opening 17. Here, and preferably, the angular distance between the third wall opening 17 and the fourth wall opening 18, measured with respect to the piston carrier axis 3, is approximately 20° (measured between the centers of the wall openings). In other words, the third wall opening 17 and the fourth wall opening 18 are arranged close together in the circumferential direction of the cylinder chamber 14. The position of the fourth wall opening 18 in the cylinder wall 13 is such that, during normal operation of the internal combustion engine 1, the piston openings 11 and the fourth wall opening 18 temporarily overlap when the respective piston 7, 8 passes the fourth wall opening 18.This overlap means that - as long as it exists - air from outside the cylinder chamber 14 can enter the cavity 10 of the respective piston 7, 8 through the fourth wall opening 18 and through the piston opening 11 (see . Fig. 14) The fourth wall opening 18 can also be designed in the form of an elongated hole, unlike the one shown in the figures, so that the overlap of the fourth wall opening 18 with the piston opening 11 lasts longer when the respective piston 7, 8 moves past the fourth wall opening 16 than with a “round” fourth wall opening 18, as shown in the figures.

[0099] The third wall opening 17 and the fourth wall opening 18 are fluidically connected to each other by means of the second flow connection 35. Similar to the first flow connection 34, the second flow connection 35 is also formed here, and preferably by a flow channel mounted on the outside of the cylinder wall 13, which connects the third wall opening 17 and the fourth wall opening 18. In this way, during operation of the internal combustion engine 1, air, which is located in front of the respective piston 7, 8 (viewed in the direction of rotation 62 of the piston assembly 4) and is highly compressed, can flow through the third wall opening 17, the second flow connection 35, the fourth wall opening 18, and the respective piston opening 11 into the cavity 10 of the respective piston 7, 8 when the respective piston 7, 8 is in a corresponding position in which its piston opening 11 and the fourth wall opening 18 overlap.Once the piston 7, 8 has passed the fourth wall opening 18 in such a way that the overlap of the latter with the piston opening 11 is terminated, the compressed air is "trapped" in the cavity 10 of the piston 7, 8 and is transported by the piston 7, 8 along the piston path. As described above, the compressed air is thus "carried along" into the combustion zone 21 to later serve in the formation of the air-fuel mixture.

[0100] The cylinder wall 13 further comprises a fifth wall opening 19 and a sixth wall opening 20, which also each penetrate the cylinder wall 13 and, viewed in the direction of rotation 62 of the piston unit 4 with respect to one revolution of the piston unit 4 about the piston carrier axis 3, are arranged downstream of the combustion zone 21 and upstream of the compression zone 22. Consequently, the fifth wall opening 19 and the sixth wall opening 20 are arranged between the combustion zone 21 and the compression zone 22, with each piston 7, 8, during one revolution of the piston unit 4, first passes through and exits the combustion zone 21, then passes the sixth wall opening 20 and the fifth wall opening 19, and then reaches and passes through the compression zone 22 (see Fig. 11, Fig. 12 to Fig. 13).

[0101] The fifth wall opening 19 is used here, and preferably, to introduce a cooling airflow from outside the cylinder chamber 14 into the cylinder chamber 14 through the fifth wall opening 19 during the intended operation of the internal combustion engine 1. For this purpose, in the example shown, the fifth wall opening 19 is fluidically connected to a compressor unit 37 of the internal combustion engine 1 by means of a third flow connection 38. The compressor unit 37, which is explained separately below, continuously provides a volume flow of compressed air during the operation of the internal combustion engine 1. This compressed air flow is introduced into the cylinder chamber 14 as a cooling airflow via the third flow connection 38 of the fifth wall opening 19 and finally through the fifth wall opening 19. Introducing the cooling airflow into the cylinder chamber 14 has the effect of cooling the cylinder wall 13 from the inside.

[0102] The sixth wall opening 20 is designed and configured to allow either the cooling airflow introduced into the cylinder chamber 14 via the fifth wall opening 19 or an exhaust gas flow from the cylinder chamber 14 to be discharged into the external area 23. Which of these volume flows, i.e., the cooling airflow or the exhaust gas flow, exits the cylinder chamber 14 through the sixth wall opening 20 in any given case depends on the position of the two pistons 7, 8 on their respective piston paths.

[0103] Here, and preferably, the sixth wall opening 20 is arranged upstream of the fifth wall opening 19 when viewed in the direction of rotation 62 of the piston unit 4. This means that, during one revolution of the piston unit 4, the pistons 7, 8, as they move along their piston path, reach the sixth wall opening 20 and then the fifth wall opening 19 after leaving the combustion zone 21. Here, and preferably, the sixth wall opening 20, viewed in the direction of rotation 62 of the piston unit 4, is the next wall opening that each piston 7, 8 reaches as it moves along its piston path after passing the second wall opening 16.This implies that the gases formed as a result of the combustion of the air-fuel mixture, which, viewed in the direction of rotation 62 of the piston unit 4, are located behind the respective piston 7, 8 when it leaves the combustion zone 21, are still trapped behind the piston 7, 8 until they have a way to escape from the cylinder chamber 14. This possibility is created by the sixth wall opening 20. Thus, the piston 7, 8 passes the sixth wall opening 20 until it is located behind the piston 7, 8 (see ). Fig. 11) The sixth wall opening 20 is then available to the exhaust gas flow formed from the gases, allowing it to escape from the cylinder chamber 14. Due to the pressure conditions, the exhaust gas flow escapes abruptly through the sixth wall opening 20 into the external area 23. Here, and preferably, the internal combustion engine 1 includes an exhaust system (not shown in the figures) that interacts with the sixth wall opening 20 from the outside and through which the exhaust gas flow can escape. The exhaust system can be designed in a manner known per se and, in particular, can act as a silencer for the abruptly exiting exhaust gas flow.

[0104] The moment the respective piston 7, 8 has passed the sixth wall opening 20, the piston 7, 8 fluidically separates the fifth wall opening 19, located downstream of the sixth wall opening 20, from the sixth wall opening 20. As a result, at the moment the exhaust gas flow exits the cylinder chamber 14 through the sixth wall opening 20, the cooling air flow introduced through the fifth wall opening 19 is not present at the sixth wall opening 20. In this position of the piston 7, 8, the sixth wall opening 20 thus serves (solely) to discharge the exhaust gas flow from the cylinder chamber 14. Depending on the distance of the fifth wall opening 19 from the sixth wall opening 20, the interruption of the flow-related connection between the two aforementioned wall openings 19, 20 continues until the piston 7, 8 has also passed the fifth wall opening 19 (see Fig. 13).

[0105] Here, and preferably, the angular distance between the fifth wall opening 19 and the sixth wall opening 20, measured with respect to the piston axis 3, is approximately 60° (measured between the centers of the wall openings). This results in the fluid flow connection between the fifth wall opening 19 and the sixth wall opening 20 being interrupted twice during one revolution of the piston assembly 4 about the piston carrier axis 3, namely whenever one of the two pistons 7, 8 has just passed the sixth wall opening 20 in the manner described, but not yet the fifth wall opening 19 (as, for example, in Fig. 12) Before each piston 7, 8 reaches the sixth wall opening 20, a fluid connection exists between the fifth wall opening 19 and the sixth wall opening 20. This connection also exists once the respective piston 7, 8 has passed the fifth wall opening 19. Thus, for a significant portion of a revolution of the piston assembly 4 around the piston carrier axis 3, the sixth wall opening 20 serves to discharge the cooling airflow introduced into the cylinder chamber 14 via the fifth wall opening 19. This is particularly advantageous so that the cooling airflow can be maintained continuously and thus contribute continuously to the internal cooling of the cylinder wall 13.

[0106] Here, and preferably, the angular distance between the second wall opening 16 and the sixth wall opening 20, measured with respect to the piston carrier axis 3, is approximately 90° (measured between the centers of the wall openings). This distance, and thus the position of the sixth wall opening 20, is preferably selected such that the pistons 7, 8 each pass the sixth wall opening 20 on one revolution (see Fig. 11) and thus release the sixth wall opening 20 for the exhaust gas flow before the next recess 29, 30 of the sealing body 27 opens towards the combustion zone 21 (at the rear end of the combustion zone 21) and the sealing body 27 temporarily loses its contact with the carrier body 5 at the contact point 45 (because of the respective recess 29, 30).

[0107] Furthermore, the angular distance, measured here and preferably with respect to the piston carrier axis 3, between the fifth wall opening 19 and the fourth wall opening 18, which is arranged downstream of the fifth wall opening 19 in the direction of rotation 62 of the piston unit 4 and which each piston 7, 8 reaches next during its movement along its piston path starting from the fifth wall opening 19, is also approximately 90° (measured between the centers of the wall openings). This distance, and thus the position of the fifth wall opening 19, is preferably selected such that the pistons 7, 8 each cover the fifth wall opening 19 for the first time on one revolution (see Fig. 12) and thus enclose air in the compression zone 22 between itself and the sealing body 27 when the previous recess 29, 30 of the sealing body 27 has just closed towards the compression zone 22 (at the front end of the compression zone 22) and the sealing body 27 and the piston carrier 5 are again in sealing contact with each other at the contact point 45.

[0108] The sealing device 25 comprises a sealing element 27 that is rotatable about a sealing element axis 26. The sealing element 27 is preferably annular in shape, with its center of gravity located on the sealing element axis 26. The sealing element axis 26 is oriented parallel to the piston carrier axis 3 and arranged at a distance 36 from it. In the example shown, the sealing element 27 has two recesses 29, 30, which are diametrically opposed to each other with respect to the sealing element axis 26. The recesses 29, 30 are configured such that they extend radially inwards from an outer edge 58 of the sealing element 27 with respect to the sealing element axis 26. The outer edge 58 of the sealing body 27 extends around the sealing body axis 26 in a sealing body radius 28. The sealing body 27 is arranged here, and preferably in an annular sealing body housing 61.

[0109] The sealing element 27 is designed and configured to seal the cylinder chamber 14 in the area of ​​a sealing zone 24. Here, and preferably, the combustion / compressor assembly 2 and the sealing element 25 are arranged relative to each other such that a piston carrier plane 9 oriented perpendicular to the piston carrier axis 3, in which the piston carrier 5 and the two pistons 7, 8 are located, and a sealing element plane 31 oriented perpendicular to the sealing element axis 26, in which the sealing element 27 and its recesses 29, 30 are located, are congruent. This is particularly evident from the following: Fig. 3. The distance 36, measured perpendicular to the piston carrier axis 3, between the piston carrier axis 3 and the sealing element axis 26 corresponds here, and preferably, to the sum of the piston carrier radius 6 and the sealing element radius 28. The distance 36 is thus selected such that the sealing element 27 and the piston carrier 5 come into tight contact and interact at a contact point 45, rolling against each other during operation of the internal combustion engine 1 (the piston carrier 5 in the direction of rotation 62 and the sealing element in the opposite direction 65). At the contact point 45, the sealing element 27 and the piston carrier 5 are in contact with each other along a contact line that extends in a plane perpendicular to the piston carrier axis 3. Furthermore, the sealing element 27 projects into the cylinder chamber 14, since the latter extends radially outside the piston carrier 5 with respect to the piston carrier axis 3.This “overlap” of the sealing body 27 with the cylinder chamber 14 is particularly evident from the . Fig. 2, Fig. 3, Fig. 6 and Fig. 7. Here, the sealing element 27 interacts tightly with both the piston carrier 5 (namely at the contact point 45) and the cylinder wall 13, so that the sealing element 27 is suitable for sealing the cylinder chamber 14 in the sealing zone 24. The passage of gases from the combustion zone 21 to the compression zone 22 or vice versa is thus prevented.

[0110] Here, and preferably, the piston carrier radius 6 of the piston carrier 5 and the sealing element radius 28 of the sealing element 27 are equal in magnitude. In this way, the sealing element 27 and the piston carrier 5 roll against each other without slippage at the contact point 45, with the piston carrier 5 rotating in the direction of rotation 62 and the sealing element 27 rotating in the opposite direction to the direction of rotation 62 in the opposite direction of rotation 65.

[0111] For interaction with the sealing element 27, the cylinder wall 13 is cut out according to the shape of the sealing element 27, so that the sealing element 27 can move along the cylinder wall 13 in a tight manner. This is particularly evident from Fig. 6 recognizable.

[0112] The sealing zone 24 of the cylinder chamber 14, formed by the sealing element 27, is located downstream of the compression zone 22, between the compression zone 22 and the combustion zone 21, in the direction of rotation 62 of the piston unit 4. On one full revolution of the piston unit 4, which, by definition according to the present application, begins when a first piston 7 reaches the combustion zone 21 (see Fig. 8), this first piston 7 initially passes through the combustion zone 21, then passes the sixth wall opening 20 and the fifth wall opening 19, then reaches and passes through the compression zone 22 and finally reaches and passes through the sealing zone 24, before it once again reaches the combustion zone 21, thus completing its rotation. A position that the first piston 7 passes through when traversing the sealing zone 24 is shown in Fig. 16 illustrated.

[0113] The sealing of the cylinder chamber 14 in the area of ​​the sealing zone 24 prevents gases from passing through this sealing zone 24. Therefore, air cannot pass from the compression zone 22 through the sealing zone 24 to the combustion zone 21. Conversely, the same applies to the passage of gases, particularly hot gases formed as a result of the combustion of an air-fuel mixture, from the combustion zone 21 through the sealing zone 24 into the compression zone 22. The sealing element 27, in conjunction with the cylinder wall 13 and the piston carrier 5, thus has the essential technical effect that, firstly, air can be compressed in the area of ​​the compression zone 22 as a result of the movement of the pistons 7, 8 on their piston paths, and secondly, the pistons 7, 8 can be driven in the area of ​​the combustion zone 21 as a result of the combustion of the air-fuel mixture.

[0114] On one revolution of the piston unit 4, the piston carrier axis 3 compresses the air a total of two times: once when the first piston 7 and once when the second piston 8 pass through the compression zone 22. With respect to one of these pistons 7 or 8, the compression of the air begins the moment the respective piston 7 or 8 covers the fifth wall opening 19 (see Fig. 12). This results in the cooling airflow introduced into the cylinder chamber 14 through the fifth wall opening 19 no longer reaching the area downstream of the respective piston 7, 8. Conversely, the air located in front of the piston 7, 8 at this moment can no longer escape. Instead, it is "trapped" between the piston 7, 8 and the sealing element 27. Egress from the cylinder chamber 14 is also not possible through the third wall opening 17 or the fourth wall opening 18, as these are coupled to each other by means of the second flow connection 35 and thus only form a small volume located outside the cylinder chamber 14, which is fluidically connected to the cylinder chamber 14. This volume, like the cylinder chamber 14 in the area of ​​the compression zone 22, is also sealed off from the outside 23.As the respective piston 7, 8 continues to move along its piston path, the air enclosed between the piston 7, 8 and the sealing element 27 is compressed. Air can only escape when, as described above, the piston opening 11 of the respective piston 7, 8 and the fourth wall opening 18 overlap (see figure). Fig. 14) At this moment, the fluid connection between the area in front of piston 7, 8, where the compressed air is located, and the cavity 10 of piston 7, 8 is established via the third wall opening 17, the second flow connection 35, the fourth wall opening 18, and the piston opening 11. The compressed air is thus transferred into the cavity 10.

[0115] The piston 7, 8, which then carries the compressed air in its cavity 10, then overcomes the sealing body 27 (and thus the sealing zone 24) by entering the recess 29, 30 of the sealing body 27 assigned to it and thereby being able to move unhindered or without collision on its piston path. On the side of the sealing zone 24 facing away from the compression zone 22, the piston 7, 8 then exits the sealing body 27 and thus reaches the combustion zone 21. There, the piston 7, 8 moves past the first wall opening 15 and then reaches the second wall opening 16. Through this, the air charged in the piston 7, 8 is guided, in the manner described above, via the first flow connection 34 and the first wall opening 15 into the area behind the piston 7, 8, where it is mixed with an injected fuel and finally ignited.The hot gases formed as a result of combustion cannot overcome the sealing element 27 towards the compression zone 22 and therefore press unabated against the rear end wall 54 of the piston 7, 8, thereby driving it. Since the piston unit 4 has a total of two pistons 7, 8, these processes, i.e., firstly the compression of air in the compression zone 22 and secondly the combustion of an air-fuel mixture in the combustion zone 21, are carried out a total of twice per revolution of the piston unit 4 around the piston carrier axis 3.

[0116] To ensure that the two pistons 7, 8 can continuously enter their respective recesses 29, 30 during operation of the internal combustion engine 1, the rotations of the piston assembly 4 about the piston carrier axis 3 and of the sealing element 27 about the sealing element axis 26 are synchronized. The sealing element 27 rotates in a counterclockwise direction 65 to the drive rotation 62 of the piston assembly 4. In the figures, this corresponds to a counterclockwise rotation of the sealing element 27.

[0117] To drive the sealing element 27, the piston carrier shaft 32 and the sealing element shaft 33 are coupled to each other in a torque-transmitting manner. The piston carrier shaft 32 is connected to the piston carrier 5 in a torque-transmitting manner. Fig. In Figure 2, this is simplified as if the piston carrier shaft 32 were manufactured integrally with the piston assembly 4, that is, the piston carrier 5 and the two pistons 7, 8. This is preferably not the case. Preferably, the piston carrier 5 is mounted on the piston carrier shaft 32, and the pistons 7, 8 are connected to the piston carrier 5, wherein, prior to the assembly of the combustion / compressor unit 2, the piston carrier shaft 32, the piston carrier 5, and the two pistons 7, 8 were separate components. The piston carrier shaft 32 extends parallel to the piston carrier axis 3. Similarly, the sealing element shaft 33 is connected to the sealing element 27 in a torque-transmitting manner, with the sealing element shaft 33 extending parallel to the piston carrier shaft 32 and parallel to the sealing element axis 26.

[0118] This implies that the sealing body axis 26 and the piston carrier axis 3 are also oriented parallel to each other.

[0119] By coupling the piston carrier shaft 32 with the sealing element shaft 33, the torque generated during operation of the internal combustion engine 1 as a result of the combustion of the air-fuel mixture at the piston assembly 4 can first be transmitted from the piston assembly 4 to the piston carrier shaft 32, via the described coupling to the sealing element shaft 33, and finally via the latter to the sealing element 27. The coupling of the piston carrier shaft 32 and the sealing element shaft 33 is such that their directions of rotation are opposite to each other. Here, and preferably, the piston carrier shaft 32 interacts with a first toothed disk 39, and the sealing element shaft 33 interacts with a second toothed disk 40. The two toothed disks 39, 40 each have an outer toothed ring 41, 42, and are arranged relative to each other such that the toothed rings 41, 42 mesh with each other.This type of coupling is mechanically very easy to manufacture and, as desired, reverses the direction of rotation from the piston carrier shaft 32 to the sealing element shaft 33. Furthermore, this type of coupling is slip-free, ensuring that the synchronization between the piston assembly 4 and the sealing element 27 remains permanently intact. Here, and preferably, the transmission ratio of the rotation of the piston carrier shaft 32 to the sealing element shaft 33 is 1:1.

[0120] Here, and preferably, the internal combustion engine 1 comprises the compressor unit 37 mentioned above, which is designed here in the form of a turbo compressor. Working in conjunction with this, the internal combustion engine 1 also comprises the third flow connection 38 mentioned above, by means of which air compressed by the compressor unit 37 can be directed to the fifth wall opening 19 and thus introduced into the cylinder chamber 14. Here, and preferably, the compressor unit 37 is indirectly coupled to the piston carrier shaft 32. As can be seen in particular from the Fig.As shown in Figure 3, the compressor assembly 37 comprises a plurality of impeller blades 59 arranged on a compressor shaft 60. The latter is connected in a torque-transmitting manner to the second toothed disc 40, which, as described above, is coupled to the piston carrier shaft 32 via the first toothed disc 39 and is driven by the latter. Thus, a rotary motion of the piston carrier shaft 32 is transmitted via the two toothed discs 39 and 40 to the compressor shaft 60, thereby also driving the latter by rotation. By the action of the impeller blades 59, air is drawn in from the environment and compressed in a manner known per se. The compressed air is taken over at one end of the compressor assembly 37 by the stationary third flow connection 38 and directed to the fifth wall opening 19, so that it can enter the cylinder wall 14 as a cooling airflow.

[0121] Finally, the internal combustion engine 1 further comprises a cooling device (not shown in the figures) which interacts with an outer surface of the cylinder wall 13 and is thus designed and configured to cool the cylinder wall 13. The cooling device can, in particular, operate according to the principle of water cooling and, in a manner known per se, have several fluid lines connected to a coolant reservoir and a radiator. Reference symbol list 1 Internal combustion engine 2 Combustion engine / compressor unit 3 Piston carrier axis 4 piston unit 5 piston carriers 6 Piston carrier radius 7 pistons 8 pistons 9 Piston carrier plane 10 Cavity 11 Piston opening 12 cylinder unit 13 Cylinder wall 14 cylinder room 15 first wall opening 16 second wall opening 17 third wall opening 18 fourth wall opening 19 fifth wall opening 20 sixth wall opening 21 combustion zone 22 Compaction zone 23 Outdoor area 24 sealing zone 25 Sealing device 26 Sealing body axis 27 sealing elements 28 Sealing body radius 29 Exclusion 30 Exclusion 31 Sealing body level 32 Piston carrier shaft 33 Sealing body shaft 34 first flow connection 35 second flow connection 36 distance 37 Compressor unit 38 third flow connection 39 Toothed disc 40 toothed disc 41 Sprocket 42 Sprocket 43 Ignition device 44 Injection system 45 Contact point 46 Edge surface of the piston carrier 47 slots 48 Flank of the cylinder wall 49 lateral contact surface of the piston carrier 50 inner surface area of ​​the cylinder wall 51 outer edge of the piston carrier 52 Central axis of the piston 53 front end wall of the piston 54 rear end wall of the piston 55 piston wall 56 first half-shell of the cylinder wall 57 second half-shell of the cylinder wall 58 outer edge of the sealing body 59 running blades 60 compressor shaft 61 Sealing body housing 62 Drive direction 63 Fasteners 64 Central axis of the cylinder chamber 65 Counter-rotation

Claims

[1] Internal combustion engine (1) comprising a) an internal combustion / compressor unit (2) with - a piston unit (4) rotatable in a drive direction about a piston carrier axis (3), comprising a piston carrier (5) and at least one piston (7, 8) rigidly connected to the piston carrier (5) and projecting radially outwards beyond the piston carrier (5) relative to the piston carrier axis (3) and an outer piston carrier radius (6) of the piston carrier (5), wherein the piston (7, 8) encloses a cavity (10) and has a piston opening (11) through which air from outside the piston (7, 8) can enter the cavity (10) and exit the cavity (10), - a stationary cylinder unit (12) which has a cylinder wall (13) that spatially delimits a cylinder space (14) extending in an annular shape around the piston carrier axis (3), wherein the cylinder unit (12) is arranged relative to the piston unit (4) and its dimensions are matched to the piston unit (4) such that the piston (7, 8) is located within the cylinder space (14) and is movable on a circular piston path within the cylinder space (14) during a rotational movement of the piston unit (4) in the direction of rotation about the piston carrier axis (3), wherein the piston (7, 8) is sealed against the cylinder wall (13), wherein the cylinder wall (13) has a first wall opening (15) and a second wall opening (16), each of which penetrates the cylinder wall (13) and each of which is assigned to a combustion zone (21) of the cylinder space (14) extending over a partial circumference of the cylinder space (14), wherein the first wall opening (15) is provided and arranged to allow air or an air-fuel mixture to enter the combustion zone (21) through the first wall opening (15) from outside the cylinder chamber (14), wherein the second wall opening (16) – viewed in the direction of rotation of the piston assembly (4) – is arranged downstream of the first wall opening (15) and its position in the cylinder wall (13) is aligned with the piston opening (11) of the piston (7, 8) such that, during normal operation of the internal combustion engine (1), the piston opening (11) and the second wall opening (16) overlap when the piston (7, 8) moves along its piston path, allowing air in the cavity (10) of the piston (7, 8) to escape through the piston opening (11) from the cavity (10) and through the second wall opening (16) from the cylinder chamber (14). wherein the cylinder wall (13) has a third wall opening (17) and a fourth wall opening (18), each of which penetrates the cylinder wall (13) and each of which is assigned to a compression zone (22) of the cylinder space (14) extending over a partial circumference of the cylinder space (14), wherein the third wall opening (17) is provided and arranged so that air can escape from the cylinder chamber (14) through the third wall opening (17), wherein the fourth wall opening (18) – viewed in the direction of rotation of the piston assembly (4) – is arranged upstream of the third wall opening (17) and its position in the cylinder wall (13) is aligned with the piston opening (11) of the piston (7, 8) such that, during normal operation of the internal combustion engine (1), the piston opening (11) and the fourth wall opening (18) overlap when the piston (7, 8) moves along its piston path, allowing air from outside the cylinder chamber (14) to enter the cavity (10) of the piston (7, 8) through the fourth wall opening (18) and through the piston opening (11). wherein the cylinder wall (13) has a fifth wall opening (19) and a sixth wall opening (20), each of which penetrates the cylinder wall (13) and is arranged - viewed in the direction of rotation of the piston assembly (4) - downstream of the combustion zone (21) between the combustion zone (21) and the compression zone (22), wherein the fifth wall opening (19) is provided and arranged so that during normal operation of the internal combustion engine (1) an airflow from outside the cylinder chamber (14) can enter the cylinder chamber (14) through the fifth wall opening (19), wherein the sixth wall opening (20) is provided and arranged to allow an exhaust gas flow to escape from the cylinder chamber (14), b) a sealing device (25) with a sealing body (27) which is rotatable about a sealing body axis (26) oriented parallel to the piston carrier axis (3), wherein the sealing body (27) has a number of recesses (29, 30) formed radially inwards with respect to the sealing body axis (26) and an outer sealing body radius (28) of the sealing body (27), which correspond to a number of pistons (7, 8) of the piston unit (4), c) a piston carrier shaft (32) connected to the piston carrier (5) in a torque-transmitting manner and extending parallel to the piston carrier axis (3), d) a sealing element shaft (33) connected to the sealing element (27) in a torque-transmitting manner, oriented parallel to the piston carrier shaft (32) and extending parallel to the sealing element axis (26), e) a first flow connection (34) which fluidically connects the first wall opening (15) and the second wall opening (16) so that - when the piston opening (11) and the second wall opening (16) overlap - air from the cavity (10) of the piston (7, 8) can be guided via the first flow connection (34) into the combustion zone (21) of the cylinder chamber (14), f) a second flow connection (35) which fluidically connects the third wall opening (17) and the fourth wall opening (18) so that - when the piston opening (11) and the fourth wall opening (18) overlap - air from the compression zone (22) of the cylinder chamber (14) can be guided via the second flow connection (35) into the cavity (10) of the piston (7, 8), wherein a distance (36) measured perpendicular to the piston carrier axis (3) between the piston carrier axis (3) and the sealing element axis (26) is of such a magnitude that the sealing element (27) projects into the cylinder chamber (14) and is designed to interact in a sealing manner with the piston carrier (5) and the cylinder wall (13), such that the sealing element (27) seals the cylinder chamber (14) in a sealing zone (24) which - viewed in the direction of rotation of the piston assembly (4) - is located downstream of the compression zone (22) between the combustion zone (21) and the compression zone (22), wherein the piston carrier shaft (32) and the sealing element shaft (33) are coupled to each other in a torque-transmitting manner, wherein the recess (29, 30) of the sealing body (27) is designed in such a way as to be complementary to the piston (7, 8) and is arranged on the sealing body (27) and the sealing body (27) is arranged and aligned in such a way as to be complementary to the piston assembly (4) that the piston (7, 8) during normal operation of the internal combustion engine (1) can enter the recess (29, 30) of the sealing body (27) as it moves along its piston path and can thus overcome the sealing zone (24) from its side facing the compression zone (22) to its side facing the combustion zone (21) without collision. [2] Internal combustion engine (1) according to claim 1, characterized by, that the combustion / compressor device (2) and the sealing device (25) are arranged relative to each other in such a way that a piston carrier plane (9) of the piston carrier (5) oriented perpendicular to the piston carrier axis (3) and containing the piston track of the piston (7, 8) and a sealing body plane (31) of the sealing body (27) oriented perpendicular to the sealing body axis (26) and in which the recess (29, 30) extends are at least substantially congruent. [3] Internal combustion engine (1) according to any one of the preceding claims, characterized by, that the piston unit (4) as a whole, preferably exactly, has two pistons (7, 8) arranged diametrically opposite each other with respect to the piston carrier axis (3) on the piston carrier (5), each projecting radially outwards beyond the piston carrier (5) with respect to the piston carrier axis (3) and an outer piston carrier radius (6), wherein preferably both pistons (7, 8) are located in a common piston carrier plane (9). [4] Internal combustion engine (1) according to any one of the preceding claims, characterized by , that the piston carrier radius (6) of the piston carrier (5) corresponds to the sealing body radius (28) of the sealing body (27). [5] Internal combustion engine (1) according to any one of the preceding claims, characterized by, that the piston carrier shaft (32) interacts with a first toothed disk (39) and the sealing element shaft (33) with a second toothed disk (40), wherein the toothed disks (39, 40) each have an outer toothed ring (41, 42) and are arranged relative to each other such that the toothed rings (41, 42) mesh with each other. [6] Internal combustion engine (1) according to any one of the preceding claims, characterized by , that the piston carrier shaft (32) and the sealing element shaft (33) are coupled to each other in such a way that a rotation of the piston carrier shaft (32) can be transferred to the sealing element shaft (33) in a transmission ratio of 1:

1. [7] Internal combustion engine (1) according to any one of the preceding claims, characterized by , that an outer edge surface (46) of the piston carrier (5) with respect to the piston carrier axis (3) - considered in a cross-section of the piston carrier (5) guided parallel to the piston carrier axis (3) - is shaped in a concave curve. [8] Internal combustion engine (1) according to any one of the preceding claims, characterized by , that the cylinder wall (13) is radially slotted inwards with respect to the piston carrier axis (3) and with its flanks (48) facing the slot (47) in a direction parallel to the piston carrier axis (3) is in sealing contact laterally with lateral contact surfaces (49) of the piston carrier (5). [9] Internal combustion engine (1) according to claims 6 and 7, characterized by , that the cylinder wall (13) - viewed in a cross-section parallel to the piston carrier axis (3) - is formed in a circular arc shape between its flanks (48), wherein the piston carrier (5) projects into the slot (47) of the cylinder wall (13) such that the concave curved edge surface (46) of the piston carrier (5) completes an inner lateral surface (50) of the cylinder wall (13) in the area of ​​the slot (47) at least approximately to a full circle. [10] Internal combustion engine (1) according to any one of the preceding claims, characterized by a compressor device (37), preferably in the form of a turbo compressor, and a third flow connection (38), wherein the compressor device (37) is coupled to the piston carrier shaft (32) or the sealing element shaft (33) and can be driven by a rotary movement of the piston carrier shaft (32) or the sealing element shaft (33), wherein the compressor device (37) is fluidically connected to the fifth wall opening (19) of the cylinder wall (13) by means of the third flow connection (38) in such a way that air compressed by means of the compressor device (37) can be introduced into the cylinder space (14) via the third flow connection (38). [11] Internal combustion engine (1) according to any one of the preceding claims, characterized byan ignition device (43) which is arranged in a section of the cylinder wall (13) associated with the combustion zone (21) and is designed and equipped to ignite air-fuel mixture located in the combustion zone (21). [12] Internal combustion engine (1) according to any one of the preceding claims, characterized by an injection device (44) which is arranged in a section of the cylinder wall (13) associated with the combustion zone (21) and is designed and configured to inject fuel into the combustion zone (21). [13] Internal combustion engine (1) according to any one of the preceding claims, characterized by a cooling device which interacts with an outer surface of the cylinder wall (13) and is designed and configured to dissipate waste heat adhering to the cylinder wall (13), wherein the cooling device is preferably designed in the manner of a liquid cooling system. [14] Method for operating an internal combustion engine (1) comprising the following process steps: - By means of a piston (7, 8) rotating on a circular piston path within an annular cylinder space (14), air which is located in a compression zone (22) of the cylinder space (14) extending over a partial circumference of the cylinder space (14) in front of the piston (7, 8) in a direction of movement of the piston (7, 8) is compressed; - The compressed air is transferred into a cavity (10) of the piston (7, 8); - Loaded with compressed air, the piston (7, 8) overcomes a sealing zone (24) during its further movement along its piston path and enters a combustion zone (21) of the cylinder chamber (14) extending over a further partial circumference of the cylinder chamber (14); - In the combustion zone (21) the compressed air located in the cavity (10) of the piston (7, 8) is introduced into an area - viewed in the direction of movement of the piston (7, 8) - behind the piston (7, 8) into the cylinder space (14) and used to form an air-fuel mixture; - The air-fuel mixture is ignited, whereupon it burns explosively, with the hot gases formed as a result of the combustion driving the piston (7, 8) on its piston path. [15] Method according to claim 14, characterized by , that the piston (7, 8) to overcome the sealing zone (24) from the compression zone (22) enters a recess (29, 30) of a rotary-driven sealing element (27) and, upon further movement along its piston path towards the combustion zone (21), exits again from the recess (29, 30), the sealing element (27) sealing the cylinder space (14) in the sealing zone (24).

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