EP0221169A1

EP0221169A1 - Internal combustion engine, particularly free piston engine

Info

Publication number: EP0221169A1
Application number: EP19860903297
Authority: EP
Inventors: Detlef Köppen
Original assignee: Individual
Current assignee: Individual
Priority date: 1985-04-24
Filing date: 1986-04-22
Publication date: 1987-05-13
Also published as: AU5953286A; DE3514787C2; SU1600638A3; DE3514787A1; WO1986006444A1

Abstract

Le moteur ci-décrit comporte au moins un cylindre à l'intérieur duquel est agencé de manière mobile un piston qui peut exécuter des mouvements de course axiale dans le cylindre et qui possède des rallonges cylindriques s'étendant des deux côtés dans le sens axial à partir du piston et présentant au moins partiellement un diamètre inférieur à celui du piston, ces rallonges étant guidées partiellement dans les alésages axiaux. Le cylindre possède des espaces de combustion qui sont formés de parties des surfaces intérieures de la paroi du cylindre et de parties des surfaces du piston ainsi que de ses rallonges. Des orifices sont ménagés dans la paroi longitudinale du cylindre pour l'admission de l'air ou de mélange air-carburant ainsi que pour l'évacuation des gaz brûlés, ces orifices d'admission et d'évacuation pouvant être respectivement ouverts ou fermés selon la position axiale du piston. Des canaux sont prévus à l'intérieur du piston et de ses rallonges pour permettre le passage régulé de gaz frais destinés à la combustion, ces canaux étant en communication avec des perçages dans la surface de l'enveloppe des rallonges. Par l'intermédiaire de ces perçages, les canaux peuvent, pour des positions axiales du piston dans le cylindre à peu près identiques, être mis en communication ou fermés à la communication avec les espaces de combustion, les orifices d'évacuation étant également libérés ou obturés par le piston.The engine described below comprises at least one cylinder inside which is movably arranged a piston which can execute movements of axial stroke in the cylinder and which has cylindrical extensions extending on both sides in the axial direction to starting from the piston and having at least partially a diameter smaller than that of the piston, these extensions being partially guided in the axial bores. The cylinder has combustion spaces which are formed from parts of the interior surfaces of the cylinder wall and parts of the surfaces of the piston and its extensions. Holes are provided in the longitudinal wall of the cylinder for the admission of air or of air-fuel mixture as well as for the evacuation of the burnt gases, these intake and evacuation holes being able to be respectively opened or closed according to the axial position of the piston. Channels are provided inside the piston and its extensions to allow the regulated passage of fresh gases intended for combustion, these channels being in communication with holes in the surface of the envelope of the extensions. Via these holes, the channels can, for approximately identical axial positions of the piston in the cylinder, be placed in communication or closed to communication with the combustion spaces, the evacuation orifices also being released or closed by the piston.

Description

V e r b r e n n s g m o t o r, in particular single-piston engine

Description

54. The invention relates to an internal combustion engine, in particular a free-piston engine, in accordance with the preamble of patent claims 1 and 54.

Internal combustion engines have pistons guided in cylinders which limit crennrcume with the cylinders, in which air-fuel mixtures are ignited. The kinetic energy of the calves is transmitted for driving mechanically, for example, or in the case of free-piston engines especially with pneumatic, but preferably hycrculic media.

An internal combustion engine of this type is known from DE-PS 28 68 06. In this well-known internal combustion engine, there are. on both ends of the piston lugs compression chambers to compress the charge air for combustion. The air flows into the compression chambers through racial openings in the cylinder turn in the area of the piston ends on both cylinders, the radial inlet openings having to be controlled by separate piston slides. The pre-compressed air then flows through radial bores in the calf approaches controlled by these into the interior of the hollow collapse, via channels to the opposite piston and from there via the corresponding piston suction radical openings in the assigned combustion chamber. On the return stroke of the piston, the air flow direction changes, the Celts. Combustion gases emerge from the combustion chambers via the outer end of the cylinder and are controlled from the piston end side via the plane of symmetry. The well-known internal combustion engine transfers its power mechanically by means of a piston rod to cufien and therefore does not provide a free piston actuator.

This well-known engine has the disadvantage that: separate piston spools are required for the inlet control in addition to the radial bores in the piston ports. The mode of operation and engine control of this engine is expensive and very unreliable, the gos flow through the cesem piston is long, complicated and very lossy, whereby due to the strong expansion in the hollow pistons the relatively high, very power consuming precompression is largely lost. The gas changes with each piston stroke, the fuel fill and the mixing of fuel and air are ineffective, are complex and complicated.

In contrast, the invention is based on the task of improving an internal combustion engine, in particular a free-piston engine with a similar exhaust according to the features of the preamble of potential claims 1 and 34, so that a simpler, more versatile and more effective, and more reliable control and working method, but you ch Antri ebsv erbincun g du fb es particularly cost-effective way. of claim 1 and 34 solved.

These measures primarily ensure that the supply of the air or mixture of air and fuel into the combustion chambers and the removal of the combustion gas from the combustion chambers are short, streamlined paths with little loss due to the position of the piston with its two cylindrical approaches controlled in a particularly reliable and simple manner. For this purpose, the piston with its two cylindrical attachments is measured, the channels and bores are still separate from each piston length half, assigned according to claim 34 and assigned to the inlet openings, which are only arranged in the center of the cylinder, and to the outlet openings of the cylinder, which are arranged on both sides

Depending on the piston position, the inlet openings with the bores and oils are in permanently open connection or in accordance with claim 1, each with a piston half and its intake, or they are locked there and the assigned outlet openings of this piston halves are released or locked . The air or the air / fuel mixture thus flows lossily through the channels and the bores into the combustion chambers and here at a short distance along the wall of the combustion chambers. The combustion gases are pushed out practically completely out of the combustion chambers, so that a quick, optimal change of lecen takes place in the combustion chambers. For the purpose, a homogeneous air / air mixture in the to achieve and recover a good and quick change of lungs, in a preferred further development of the invention the channels are so cusgebilcet according to the invention in the cylindrical attachments that their munitions on the jacket holes have these cylindrical attachments in a narrow manner, the injection nozzles and / or ignition electrodes also in a critical arrangement in toroieertice, to the cyclic attachments of the kooxicle recesses in the frontal surface of the firing chamber. These measures ensure that the air entering the combustion chamber or the combustion chamber is optimally flushed out of the combustion gases and that there is good charging, mixing and combustion, the effect of which is particularly favorable and effective on the piston movement and thus on the performance which can be achieved of the motor acts on the drive.

At the same time, the toroid-specific design of the combustion chambers makes it possible to specify the smallest volume of the combustion chambers (tetpoint volume) and thus the maximum compression of the air / fuel mixture as well as the combustion objective of the mixture and its usable effect. According to the invention, in the y-bonding of the cylinder, the receiver for the new position of the piston for determining and controlling the optimum injection time for the fuel and / or the time for the ignition is crenetated. This connection between the detection of the piston position, particularly in the case of the free-piston engine, and the initiation of the combustion process, is particularly important The displacement transducers are, for example, magnetic field probes which operate on the induction principle and which generate an induction voltage which is dependent on their position due to the movement of the piston.

A free-piston internal combustion engine is known from DE-AS 14 80 100. This has no channels in the piston and the inlet openings are outside the radial symmetry plane of the cylinder and, like the external channels, must be controlled from the piston ends.

Since in this known skin the inflow and outflow of the cast into the respective combustion chamber does not take place concentrically from the axis cus rediel neuss, but the inflow to the cylinder axis and the outflow must take place in the opposite direction and the inflow and outflow opposite at the end If the firing chamber takes place in the same rodicle level, very bad flow conditions, very bad gas changes and firing chamber fillings result, resulting in an unreliable, lossy and therefore ineffective way of working.

The control of inlet and outlet with only one common piston edge also leads to less reliable control and engine operation with this arrangement of the inlet and outlet openings.

In Ger DE-A S 14 80 100, the kinetic energy from the piston of the free-piston internal combustion engine is transferred to a hydraulic mecium for driving hydraulic motors, for example in vehicles, whereby pumps for any pressure medium or conveying means can also be designed according to this principle.

From DE-OS 20 29 287 it is known to enzenoren a piston on the end faces of a piston web and in the middle between these two pistons on the piston rod. The two outer pistons each delimit a combustion chamber with the cylinder, while the middle piston with the. Cylinder delimits two spaces for precompaction of an air-fuel mixture, which is alternately fed into the combustion chambers and ignited via an overflow valve.

It is known to you (US 44 49 488, DE-OS 28 16 660), in a piston with the cylinder delimiting the combustion chambers, to include a second piston for developing chambers for precompressing the air.

In general, air or an air / fuel mixture can be supplied to the combustion chambers. In the first skin, fuel is injected into the combustion chambers. In general, ignition electrical codes can be arranged in the combustion chambers or the compression in the combustion chambers can be chosen to be high enough that the fuel / air mixture ignites automatically.

Liquid, gaseous or solid fuels can be used as fuels

Used, such as gasoline, diesel oil, heavy oil, light oil, coal dust, etc.

Freikojbenrnotoren are also known (US 42 C5 528) with a piston guided in a cylinder, the cylinder delimiting combustion chambers with the end faces of the piston, the end faces attaching and the combustion chambers having nozzles for injecting a fuel, and the wall of the cylinder inlet openings for air and has outlet openings for the combustion gases and the piston opens or blocks the inlet openings and the outlet openings depending on its position. The projections on the end faces of the piston are frustoconical and guide the air fed into the combustion chambers in such a way that the combustion chambers are flushed free of the combustion gases at the beginning of the compression stroke.

In the case of the used engines, in particular the free-piston engines, however, considerable design effort is required in order to control the introduction of air and fuel into the combustion chambers depending on the piston position. These known controls are often not reliable enough. The flow paths to and from the combustion chambers are often long, unfavorable and lossy. Therefore, the known engines are prone to malfunction in practice, despite their configuration, and place considerable demands on the rating. After all, the Mirkungsgred these engines often do not satisfy you in practice.

In a further development of the invention, the injection nozzles for the fuel and / or the ignition electrodes are arranged ready for use in the facing cylinder end facing the cylinder end facing the piston end faces of the combustion chambers. This measure also ensures that the most homogeneous possible mixture of fuel and air is formed in the combustion chambers and that this is ignited and burned as cheaply and effectively as possible.

In a further embodiment of the invention, the engine according to the invention is equipped with a device for compressing the air or the air / pulp mixture, which is arranged in the cylinder itself, or is externally arranged. In the latter case, an air pressure accumulator belongs to the compression device. The external compression of the air can be based on the principle of the turbocharger, but it is also known to be used for standardization.

In one embodiment of the invention, the use of the internal combustion engine according to the invention is provided in a medium-powered system, for example a hydraulic unit, which can be switched over to motor and pump operation, coupled to an alternator which failed when the internal combustion engine was started as a motor.

This measure creates a starting device for the internal combustion engine. During the stamping process, the light machine is fed by an accumulator, which drives the pressure medium-operated unit, for example hyerculic aggregate, which works in the pump mode, so that the internal combustion engine, pressurized with pressure medium on its end faces of the piston attachments, is tested. As soon as the internal combustion engine is started, the pressure medium-operated system works, for example, with a hydraulic unit in motor operation, whereby among other things you will be driven by the light machine, which in turn will drain the battery. In addition, the pressure medium-operated system contains a motor driven by the pressure medium, which performs the drive power of the internal combustion engine via the pressure medium and utility work. In a further embodiment of the invention, the axes of the inlet effects of the internal combustion engine for the air or of the air / pulp mixture in the cylinder wall are arranged in such a way that the axial movement of the piston is superior to a ratio movement of the piston about its longitudinal axis. Through this implementation, i.a. prevents the piston from slipping in.

Essential, not suggested further developments of the internal combustion engine according to the invention relate to the geometrical formation of the cylindrical projections of the calving whether departing from the continuous, cylindrical, smooth outer surface of the approaches, constant diameter.

Thus, it is claimed that the lugs of the piston have adjacent cylindrical longitudinal sections, each with different diameters, which are movably guided in corresponding n axial bores in the cylinder, whereby the larger cxicle length of the longitudinal sections of the cyclo-eroxial bores in the cylinder form spaces are, which by the end faces of the cylindrical longitudinal sections of the piston lugs as a result of the piston stroke movements during the combustion process in the engine become spaces of variable volume, in each of which fluid is pressurized to increase pressure.

Thus, for example, designs of the cylindrical lugs are claimed, which, on the one hand and according to a further development on both sides of a larger diameter diameter section acting as a piston disc, have at least one further cylindrical length section with a smaller diameter than the piston diameter Both the front free end of the lugs and the front sides of the longitudinal sections of the lugs with the larger diameter are made in connection with the stroke of the piston, sealed radially with respect to the corresponding bores in the cylinder, lifting movements, without at the respectively facing end of the respective bore in the Bump cylinder. Depending on the claimed embodiment and the corresponding connections for the inlet and outlet cazu, these lifting movements of the end faces of the attachments serve a fluid such as gas or a hydraulic fluid of a pressure-operated system and / or the air or the air-fuel mixture for the combustion in the To increase the pressure of the internal combustion engine.

The longitudinal sections of the piston lugs create a compressor integrated in the cylinder, for example double filling or two-stage training for the internal combustion engine, which makes a separate turbocharger unnecessary. In addition, a pressure medium pump is additionally formed as a reciprocating piston pump (e.g. one-stage with two internal pressurized and pumped pressure cores or two-stage) for a pressure-operated system for which the internal combustion engine, in particular as a free-piston engine, delivers its work.

In the inlet and outlet lines of the rooms of variable volume, there are suitable control valves, for example, as check valves or pressure-controlled, spool valves or ice valves controlled by outside valves, which are closely matched to ensure the reliable working of the displacements.

Valves for controlling or regulating the combustion chamber fillings are provided between the compression chambers for the combustion air or the air / fuel mixture and the inlet ducts of the combustion engine in the radial symmetry plane of the cylinder.

The pressure medium of the pressure medium-operated system is used according to a non-suggested further development of the invention to cool the cylinder, preferably in the area of the internal combustion engine, as it flows through the suction line to the volume in the cylinder which acts as a pump. Finally, the internal combustion engine is provided as a free-piston engine or with a mechanically controlled output on the piston or its attachments. In the reading according to claim 54, the fresh gas, which is pre-compressed for combustion, is already constantly stored in the hollow piston and is filled with air so that it can flow directly into the combustion chambers when the bores in the lateral surfaces of the projections are opened.

Two exemplary embodiments of the subject of the invention as well as an elock circuit of a system according to the invention are shown in the drawings and are explained in detail in the drawings. 1 shows a section through an exemplary embodiment of the invention

Internal combustion engine as a free-caliber engine without integrated compression with integrated pressure medium pump for hydraulic pressure medium, which is also used on the suction side for cylinder cooling.

FIG. 2 shows a cross section of the motor according to FIG. 1 with the arrangement of the pressure medium scug channels used for cytinder cooling.

3 shows a section through a further exemplary embodiment of the internal combustion engine according to the invention as a free-piston engine with an integrated compressor having a double filling volume and a pressure medium pump for hydraulic pressure medium integrated at the end for transmitting the engine power.

Figure 4 of the block diagram for the use of the engine according to the invention in a pressure medium operated system with a starter device for the internal combustion engine.

The internal combustion engine according to the embodiment of the invention according to FIG. 1 consists of a cylinder 1, in which a piston 4 is guided axially back and forth with the length of the piston stroke and radially sealed against the axially extending cylinder bore receiving it. With its end faces 26, 27, the cylinder bore forms the cylinder space 9. The piston has an end face 5, 6 on each end. Axially on both sides of the piston 4, the end faces 5,6 extend coaxially to the piston 4, cylindrical attachments 1,8 with a smaller, smaller diameter than the piston 4. The lugs 7, 8 are movable at the end and are radially sealed and are guided in further axial cylinder passages 12, 12, which are extended by the extension of the cylinder rumen 9 with the diameter etvvc equal to that of the extensions 1.8 in the cylinder 1, and are closed by the end of the cylinder lumen 9 one end face each 81.88. In the symmetry-radial plane 2 of the cylinder there are inlet openings 2 in the cylinder wall 100, which open radially into the cylinder space and serve to supply the air or the air / fuel mixture for combustion in the combustion chambers 10, 11 of the engine . On both sides of the inlet openings 2 are arranged at a distance b in a radial plane Z1.Z2 of the cylinder 1 radially through the cylinder longitudinal wall 100 penetrating outlet openings 2 at. The axis of the inlet openings 2 can be provided at a distance from the cylinder longitudinal axis AA such that the piston 4 is displaced about its longitudinal axis AA by the gas inflow i rotation. The piston 4 has radial openings 90, 91 in its cylindrical circumferential surface 80 (= lateral surface) which open into channels 18, 19 in the piston 4, the openings 90, 91 being arranged in wheel planes of the piston 4, which are at a distance α on both sides of the Radial symmetry plane K of the piston 4 lie. The channels 18, 19 in the piston preferably lead with an almost constant flow cross-section, each hollowing out the piston 4 as a single channel, or as a bundle of channels from the openings 90, 91 into the lugs 7, 8 of the piston 4, in order here again to open into bores 20, 21. which are preferably ring-shaped around the circumference of the respective shoulder 7, 8, arranged in a radial plane through the cylindrical jacket surfaces 101, 102 of the shoulder 7, 8, for example, introduced radially into the shoulder 7, 8. In this way, each of the two piston length halves 401, 402 is a respective flow connection from the openings 90, 91, which are preferably likewise arranged in a ring-like manner on the circumference of the piston 4 in the calf jacket surface, through which each piston length half 401, 402 and each of the lugs 7, 8 Separately assigned channels 18, 19 in the piston 4 and its lugs 7, 8 assigned to the bores 20, 21 for the passage and flow of air or an air / fuel mixture for the combustionj coming from the inlet openings 2 in the cylinder longitudinal wall 100 to into the combustion chambers 10, 11 axially to both seldom of the piston 4 in the cylinder chamber 9.

The piston 4 can have a flow channel in its circumferential direction in its circumferential direction in its radial surface K1 and K2 and / or the cylinder longitudinal wall 100 can have a flow channel in its inner surface of the cylinder space 9, for example in the manner of a circumferential depression as a groove In order to be able to produce a flow connection distributed over the circumference between the individual wreath-like inlet openings 2 and / or wreath-like openings 90, 91 on the piston skirt, which is particularly important and necessary as a free piston, especially with piston 4 rotating about its axis AA can be.

The piston 4 is radially between its circumferential surface, ie its jacket and the axial cylinder bore forming the cylinder chamber 9, preferably at the ends, but possibly also between the planes K 1 and K2 by means of sealing means such as piston rings and / or sealing rings. The cylindrical lugs 7, 8 are also at the ends, ie between the respective radial plane in which the bores 20, 21 lie and their free, front end in the cylinder bores 12, 13 via a sealing center! 14, 15 sealed like sealing rings with respect to the cylinder 1 in order to prevent an axial flow connection between the respective free, front end of the lugs 7, 8 and the combustion chambers 10, 1 1. In the end faces of the cylinder facing the piston 4 there is space 9, ie in the inner end faces 26, 27 of the cylinder 1 there are preferably toroidal recesses 83, 84 around the cylinder axis AA around the shoulders 7, 8 or the cylinder bores 12 , 13 provided, into which toroidal recesses 83, 84 which are preferably ring-shaped on a. Injection nozzles 28, 29 and / or ignition electrodes 128, 129 arranged in the cylinder 1 range and / or act, whereby the toroid-like recesses 83, 84 can approximately determine the dead volume of the combustion chambers 10, 11 with maximum compression. The dimensions and assignments of the lengths and A would be determined such that when the piston 4 with its end face 6 of its one piston half 401 is close to the end face 27 of the cylinder 1 facing it, the radial planes 2 and K 1 coincide approximately , so that there is an open connection between the inlet openings and the openings 90 of the other piston half 401, as a result of which the inlet openings 2 are in open flow connection with the channel 18 assigned to this other piston length half 401 and via the bores 20 in the extension 7 into the combustion chamber 10 , for the inflow of gas for combustion. For this purpose, the bores 20 are arranged at such a distance from the end face 5 of the piston (as are the bores 21 from the end face 6) and the axial length of the cylinder chamber 9, the piston 4, the combustion chambers 10, 11 and the lugs 7, 8 and the maximum distance between the end faces 5 and 26 or 6 and 27 so that the bores 20, 21 are then open within the cylinder chamber 9 or the combustion chambers 10, 11 when the piston 4 is close, its opposite stroke end position , is located near the end face 27, 26. Because of the largely symmetrical arrangement of the surfaces, spaces, channels, bores, spacings etc. with respect to the symmetry radial plane 2 of the cylinder 1 and the symmetry radial plane K of the piston 4, this definition applies equally to the dimensions for both strokes of the piston 4 .

Also in the area near the stroke end position of the piston 4 is in addition to the open flow connection between the inlet openings 2 and the respective combustion chamber 10 or 11 and the outlet openings 3 arranged in a common radial plane Z 1 or Z2. The outlet openings 3 of the respective radial plane 21 or 22 in this piston position near its stroke end position or dead center position through the respective end face 5 or 6 of the piston 4 released relative to the associated combustion chamber 10 or 11 so that the combustion gases can escape from the respective combustion chamber 10 or 11 in the combustion chamber 10 and 11 respectively displaced by the inflowing fresh gases coming from the inlet openings 2.

In the wall of the cylinder 1 for engine control, particularly necessary in the case of the piston 4 being designed as a free piston, for example in the end regions of the cylinder chamber 9, displacement sensors 30, 31 are arranged for detecting the position of the piston 4 during its stroke, the respective piston position signal can be used and serves to activate the injection nozzles 28, 29 or ignition electrodes 128, 129 at the right moment and time.

Further outside the two stroke end positions of the piston towards the piston towards the center position, i.e. towards the decreasing distance between the radial symmetry planes 2 and K, the flow connection between the inlet openings 2 and the openings 90, 91 is through the piston 4 itself just as wrong as the flow connection from holes 20,21 to the combustion chambers 10, 11 through the sealed outer surfaces of the lugs 78 on the one hand and the cylinder bores 12, 13 on the other hand and also wiz dier flow connection between the combustion chambers 10, 11 and the outlet openings 3 through the end faces 5,6 and sealed outer surfaces of the piston 4th

The cylinder end sides each have end faces 87, 88, which close the axial cylinder bores 12, 13 in which the free ends of the lugs 7, 8 reciprocate with the stroke of the piston 4, ver by an end wall, so that within the Cylinder bores 12, 13 between the end face 87.88 formed by the cylinder 1 and the end face of the free end of the extension 7.8 each have a space of variable volume as a pump space for a pressure medium (gas or liquid), the space having a variable volume during its Volume reduction in the course of the piston stroke increases the pressure on the pressure medium in the room of variable volume. In each of the end faces 87, 88 there are pressure medium lines 81, 82, 85, 86 leading axially to the cylinder bores 12, 13 as suction-sensitive inlet and outlet on the pressure side, in which and for the control thereof control valves 22, 23, 24, 25 are provided, for example as check valves or pressure-controlled slide valves or as control or regulating valves which are controlled externally, for example electrically.

Finally, the respective suction-side pressure medium lines 81, 82 each lead from the opposite cylinder lake from the end face 87, 88 there via pressure medium lines 81, 82 provided in the cylinder wall 100 with a surface that is as large as possible (large cross-sectional area) compared to the cylinder opening, for example also in parallel, separate ones Channels of the scugseltieen pressure medium lines 81, 82 to the other end face at the 'other cylinder end and from here via the control valve on the suction side (= inlet valve) at the end axially into the cylinder bore 12, 13. In this way, the pressure medium supplied to the cylinder 1, preferably in Area of the Zyllnderlcngswand 100 0 on the Lengen section around the Zyllnderrcum 9 and thus the internal combustion engine to be cooled.

Briefly summarized, Figure 1 shows the embodiment of a free-piston engine according to the invention. The cylinder 1 has in its wall inlet openings 2 for air and outlet openings 3 for combustion gases and guide the axially movable piston 4. The inlet openings 2 are arranged in one ring zone and the outlet openings in two ring zones. The piston 4 has on its end faces 5, 6 each a cylindrical extension 7, 8 with a smaller diameter than the piston 4. The piston is guided in a cylinder chamber 9, which it divides into the combustion chambers 10, 11. The cylindrical lugs 7, 8 immerse in all their positions in the cylinder bores 12, 13 which, as can be seen from the block diagram in FIG. 4, for example The cylindrical lugs 7, 8 are in contact with the hydraulic medium in the lines with their end faces n. For sealing against the hydraulic medium, the cylindrical lugs 7, 8 have seals 14, 15. The piston 4 can also have seals 16, 17 for sealing the combustion chambers 10, 11. The piston 4 also has channels 18, 19 which start from its outer surface and merge into bores 20, 21 of the cylindrical lugs 7, 8. Depending on the type of engine (claim 1 or claim 34), the channels are separate from one another or open to one another. The bores 20, 21 run into the lateral surfaces of the cylindrical lugs 7, 8. The mouths of the channels 18, 19 cuf on the outer surface of the piston 4 in the form of the openings 90,91 according to one solution (claim 1) in two zones K 1, K2, according to the other solution (claim 34) in one zone in the exial middle region of the piston 4, each equidistant, that is arranged in a ring-like manner. This wreath-like arrangement is made for the mouths of the bores 20, 21, which are arranged in ring zones of the cylindrical lugs 7, 8.

Combustion chambers 10, 1 1 have a toroidal recess in the end face 26, 21 of the cylinder space 9 cuf, in which the injection nozzles 28, 29 are also cross-sectional to the cylindrical attachments 1,8 opposite the end faces 5,6 'of the piston 4 of the fuel are tight. In the wall of the cylinder 1 in the area of the combustion chambers 10, 1 1 magnetic field probes ice wecaufnehmer 30,31 are arranged, which control the injection nozzles 28,29 or the additional or alternative ignition devices (ignition electrodes 128, 129) depending on the position of the Piston 4 serve.

The function of the internal combustion engine according to the invention, in particular the free-piston engine according to FIG. 1, is as follows:

Either air or mixture is supplied to the combustion chamber 10, 1 1 via the channels 18, 19 and the bores 20, 21 of the piston 4 and its cylindrical attachments 1,8. In the first case, fuel is injected via the nozzles 28, 29, auto-ignition occurring or ignition by ignition electrodes. In the position of the piston 4 shown in FIG. 1, the air or the mixture of air and fuel in the combustion chamber 11 is practically the volume of the toroidal recess 84 in the end face 21. In the final combustion chamber 10 there are the combustion gases which come out through the outlet openings 3 in the wall of the cylinder 1. The channels 18 of the piston 4 are in open flow connection with the inlet openings 2 of the cylinder, so that, for example, pre-compressed air or a compressed mixture flows through the channels 18 and the bores 20 into the combustion chamber 10 and displaces the combustion gases from the combustion chamber IG. In the right position of the piston 4 shown in FIG. 1, the latter is driven to the left after the ignition. As a result of this movement of the piston 4, the outlet openings 3 and, according to the solution of patent claim 1, the inlet openings 2 in the wall of the cylinder 1 are blocked by the piston surface and the compressed air or the mixture in the combustion chamber 10 is further compressed. The mouth of the channels 18 and bores 20 are also blocked by the piston movement. As soon as the piston has reached a preselected stroke position, the magnetic field probe 30 sends a control signal to the control of the injection nozzles 28 for injecting the fuel or to the ignition device 128 for igniting the fuel / air mixture.

As soon as the piston 4 has reached its end position on the left in the drawing, the state in the combustion chamber 10 corresponds to the state in the combustion chamber 11 shown in FIG. 1. The piston therefore makes a reciprocating movement which affects the hydraulic medium in the rooms variable volume of the cylinder bores 12, 13 transmits, whereby a hydraulic motor or a turbine can be driven.

FIG. 4 shows a block diagram of a pressure-medium-operated system for use and connection with the internal combustion engine according to the invention, preferably as a free-piston engine. This is designated by 33 in FIG. The hydraulic lines 34 and 35 lead from it to the hydraulic motor 36. A cooler 31 is arranged in the hydraulic lines 34, 35. The hydraulic motor 36 works on the. Shaft 39 of a drive for example of a vehicle such as e.g. a Kroft vehicle. The hydraulic motor 36 is followed by a pressure accumulator 40, which can be switched on or switched off. A hydraulic line 42 leads from the hydraulic roller valve 34 from a branch 41 to a starter unit 43, which is connected to the hydraulic roller valve 35 via a hydraulic roller valve with the branch 44. which can also be switched over as a generator or works as a generator, and the accumulator 48.

When starting the internal combustion engine 33, the alternator 47 operates as a motor, is fed by the accumulator 48 and drives the hydraulic power unit 46 which is switched to pump operation and which starts the internal combustion engine.

After starting the internal combustion engine 33, preferably as a free-piston engine, the hydraulic unit 46 switches over to engine operation, drives the alternator 47, which charges the accumulator 48 as a generator. For example, when braking a vehicle such as a motor vehicle, the hydraulic motor 36 works as a pump and conveys hydraulic medium into the pressure accumulator 40, the energy of which can be fed back to the hydraulic motor 36 when accelerating. The internal combustion engine 33 also has a compressor 50 for the fresh combustion air and a storage 51 for the pre-compressed fresh air, which can be supplied to the combustion chambers 10, 11. Figure 2 shows a section through the internal combustion engine, preferably

Free-piston engine according to FIG. 1, in which a possible arrangement and design of the suction-side pressure medium lines 81, 82 with the largest possible surface area through the cylinder longitudinal wall 100 is shown.

From Figure 3 shows another embodiment of the internal combustion engine according to the invention, here again a Frelkolbenmotor is shown, which corresponds to the internal combustion engine in the central region of the cylinder 1. and with regard to the pressure medium pump at the cylinder end regions with the design according to Figure 1, so that the related description of the design and function according to Figure 1 In the same way for the part of the internal combustion engine in the cylinder chamber 9, its surrounding environment and the pressure medium pump in the cylinder end areas in the cylinder bores 135 and 136 instead of 12 and 13 according to Figure 3 applies. Only with regard to the seals 14, 15 and 16, 11 are there small differences in that the lugs 7, 8 carry two sealing rings next to one another and the piston 4 between the bores 90, 91 also has at least one sealing ring in the radial plane K.

Between the internal combustion engine in the central region of the cylinder 1 with piston and the pressure medium pump In the end regions of the cylinder 1 with the cylinder bores 135 and 136, the free ends of the third longitudinal sections 125, 126 of the lugs 7, 8, the end faces 87, 88 and valves 22 to 25, which correspond in structure, arrangement and function to the exemplary embodiment according to FIG. 1, the exemplary embodiment according to FIG. 3 on both sides of the internal combustion engine in the cylinder space 9 also has a compressor integrated in the cylinder 1 for precompressing the fresh gas, such as air for the internal combustion engine, which from this integrated compressor is fed from the inlet openings 2. The compressor is formed by compressor stages arranged symmetrically on both sides to the symmetry radial plane Z of the cylinder and the symmetry radial plane K of the piston. Each of these compressor stages is formed by an axial cylinder bore 133, 134 with a larger diameter than the diameter of the cylinder bores 12, 13 and 135, 136 and an axial length that is greater than the stroke length of the piston 4. In each of the axial cylinder bores 133, 134, a piston disk is axially movably guided and sealed against the bore wall by means of sealing means 14, 15, and can be moved back and forth together with the stroke of the piston 4. This piston disk is each formed from a second axially short length section 123, 124 of the lugs 7, 8 with a larger diameter than the first and third length sections 121, 122 and 125, 126, which corresponds to the diameter of the cylinder bore 133, 134 and, for example, is equal to the diameter of the piston 4 or the cylinder space 9 is. This second longitudinal section 123, 124 of the lugs 7, 8 as ffbuie piston disc now inevitably moves when the piston 4 is lifted in the same direction and distance, without striking the ends of the cylinder bore 133, 134 in the stroke end position. The first and third length sections 121, 122 and 125, 126 adjacent to the second length section 123, 124 axiel are each sealed in their cylinder bores 12, 13, 135, 136. At both ends of the cylinder bore 133, 134 open radially through the cylinder wall guide, preferably valve-controlled inlet bores 152, 154, 156, 158 and outlet bores 151, 155, 155, 157 for the supply of pressureless fresh gas such as air for the combustion in the compressor and Derivation of pre-compressed fresh gas such as air from the compressor to the inlet openings 2. In the exemplary embodiment according to FIG. 5, the inlet bores 132, 158 and 154, 156 can be connected together for the fresh gas supply, as can the outlet bores 151, 157 and 153, 155, Via which the precompressed fresh goo may then be valve-controlled and led jointly to the inlet openings 2.

The function of the compression device is as follows:

In the increasing in the stroke of the piston 4 space in the cylinder bore 135, 134 fresh gas is sucked in like air via the valve-controlled given fur. Inlet bores 152, 158 up to the stroke end of the piston 4, vjähre at the same time compressed in the shrinking space of the cylinder bore 155, 154 of the fresh gas sucked in before the stroke and passed through the possibly valve-controlled outlet bores 153, 155 to the inlet openings 2. After reaching the stroke end of the piston 4, the piston 4 is moved in the opposite stroke direction as a result of the combustion in the engine, and the compression and contraction of the enlarging spaces inevitably alternate with each other, as does the inlet bores 152, 154, 156, 158 and the outlet bores 153, 153, 155, 157, if appropriate, can be activated in a corresponding manner in reverse with the valves assigned to them.

In the solution according to claim 34, the pre-compressed air or the pre-compressed air-fuel mixture from the compressor via the inlet openings 2 and the openings 90, 91 formed directly and preferably in the axial direction through the opening openings formed during the entire piston stroke, for this purpose constantly up to the hollow piston 4 in order to be stored there with pre-tensioning pressure and to be constantly refilled so that it can flow directly and pre-compressed into the combustion chambers 10, 11 without unnecessary relaxation when the bores 20, 21 are opened or released.

Claims

P a t e n t a n s r u c h e

1. V internal combustion engine, in particular free-piston engine, with at least one cylinder (1), with a piston (4) which is movable and sealed in it and which is guided and which can execute axial stroke movements in the cylinder chamber (9) with cylindrical projections (7, 8) on the piston (4), which extend on both sides in the axial direction away from the piston (4) and at least partially have a smaller diameter than the piston (4), the lugs (7, 8) at least partially in axial cylinder bores (12, 13) are guided and partially sealed therein, with combustion chambers (10, 11) in the cylinder (1), the surfaces of parts of the cylinder wall interior delimiting the cylinder chamber (9), on the one hand, and parts of the surfaces of the piston (4) and its projections (7, 8) are formed and delimited on the other hand, the surfaces delimiting the combustion chambers (10, 11) being formed in particular by surfaces (5 and 26 or 6 and 21) arranged on the end face, with in the cylinder longitudinal wall (100) dneten inlet openings (2) for air or air-fuel mixtures and with outlet openings (3) for combustion gases arranged in the longitudinal wall of the cylinder (100), whereby depending on the axial position of the piston (4) with its lugs (7,8), inlet openings (2) and outlet openings (3) can be opened or closed in each case with channels (18, 19) within the piston (4) and its lugs (7, 8) for the controlled passage of gases such as air or air. Fuel mixtures, these channels (18, 19) being connected to bores (20, 21) in the lateral surfaces (101, 102) of the lugs (7, 8) and the channels (18, 19) depending on the axial position of the piston (4) with its lugs (7, 8) in the cylinder (1), on the one hand, can be brought into open connection with inlet openings (2) or, on the other hand, can be shut off, and the channels (18, 19) with approximately the same axial piston positions in the cylinder (1) on the other Holes n (20, 21) can also be brought into open connection to the combustion chambers (10, 11) or can also be closed by the axial cylinder bores (12, 13), characterized in that. that the channels (18 and 19) are arranged without flow connection to each other and each separately from each other in each of the two piston length halves (401 and 402) and their extension (1 and 8), which are on both sides of the one perpendicular to the longitudinal axis (AA) Plane (4) of symmetry of the piston (4). That each of the channels (18 or 19) is in communication with openings (90 or 91) in the peripheral surface (80) of the piston (4), these openings ( 90 or 91) are arranged in the area of a radial plane (K 1 or K2) which is parallel to and at a distance (a) from the plane of symmetry (K) of the piston (4) such that all inlet openings (2) in the longitudinal wall of the cylinder (100 ) are arranged in the area of the plane of symmetry (Z) of the cylinder (1) perpendicular to the longitudinal axis (AA) such that the outlet openings (3) for each of the two combustion chambers (401 or 402) assigned to one of the piston length halves (401 or 402) 10 and 11) are arranged separately from each other ils in the area of a radial plane (Z1 or Z2) arranged parallel at a distance (b) to the plane of symmetry (Z) of the cylinder (1), and that the distances (a) on both sides of the openings (90 or 91) from the symmetry The plane (K) of the piston (4) and the spacings (b) on both sides (b) of the outlet openings (3) from the plane of symmetry (Z) of the cylinder (1) are set in such a way that all inlet openings (2) are then aligned with the one half of the piston length ( 401 or 402) associated openings (90 or 91), channels (18 or 19), bores (20 or 21), the combustion chamber (10 or 11) and the outlet openings (3) can enter into open flow connection , when the end face (6 or 5) of the other piston length half (402 or 401) is in the vicinity of the end face (21 or 26) of the cylinder space (9) facing it.

2. Internal combustion engine according to claim 1 or 34, wherein end faces of the approaches can act to increase the pressure of a fluid, so that the fluid is hydraulic fluid or gas for a pressure-operated system with which the internal combustion engine is in direct drive connection.

3. Internal combustion engine according to claim 1, 2 or 34, characterized in that the combustion chambers (10, 11) each toroidal, to the lugs (7,8) coaxially arranged recesses (83,84) in end faces (5,6 or 26, 21) have.

4. Internal combustion engine according to claim 3, so that the toroid-like recesses (83, 84) are formed in the front inner surfaces (26, 27) of the cylinder wall (9) delimiting the cylinder wall.

5. Internal combustion engine according to claim 4, d a d u r c h g e k e n n z e i c h n e t, that the toroidal recesses (83,84) are formed in the end faces (5,6) of the piston (4).

6. Internal combustion engine according to one of claims 1 to 5 or 34, wherein in the end faces of the cylinder delimiting the combustion chambers

Injection nozzles and / or ignition electrodes are arranged, which act in the combustion chambers, so that the injection nozzles (28, 29) and / or ignition electrodes (128, 129) are ring-shaped around the

Longitudinal axis (A-A) are arranged.

7. Internal combustion engine according to claim 3, so that the injectors (28, 29) and / or ignition electrodes (128, 129) open into the toroidal recesses (83, 84).

8. Internal combustion engine according to one of claims 7 to 1 or 34, characterized in that the bores (20,21) on the circumference of the lugs (1,8) and / or the inlet openings (2) on the circumference of the cylinder wall (100) and / or the outlet openings (3) on the circumference of the cylinder longitudinal wall (100) are arranged like a ring.

9. Internal combustion engine according to one of claims 1 to 8 or 34, characterized in that for controlling the injection or ignition timing displacement transducer (30,31) in the cylinder wall for detecting the axial position of the piston (4) in the cylinder (1) are.

10. Internal combustion engine nac Anspruc S, characterized in that the displacement transducers (30, 31) are magnetic field probes which operate on the induction principle and which emit a piston position-dependent voltage which is processed by means of electrically working components, the injection and / or ignition timing of the axial position of the Assign adjustable piston (4) in the cylinder (1).

11. Internal combustion engine according to one of claims 1 to 10 or 34, characterized in that the axes of the inlet openings (2) in the cylinder longitudinal wall (100) are arranged at a distance from the longitudinal axis (AA) that the piston (4) with its approaches ( 7,8) in addition to an axial stroke movement is also set in a rotational movement about the longitudinal axis (AA).

12. Internal combustion engine according to one of claims 1 to 11, d a d u r c h g e k e n n z e i c h n e t that the Kerc.'e (18,19) each as a single channel or as frets! is formed by multiple channels.

13. Internal combustion engine according to claim 12, d a d u r c h g e k e n n z e i c h n e t that the channels (18,19) are formed with an approximately constant flow cross-section.

14. Internal combustion engine according to one of claims 1 to 13 or 34, characterized in that the lugs (1,8) axially next to each other have longitudinal sections (121-126) cylindrical outer surfaces, the longitudinal sections having different diameters compared to the adjacent longitudinal sections, so that thereby end faces facing and facing away from the piston (4) are formed at an axial distance from one another, the cylindrical face surfaces of different diameters each being movably and slidably guided in axial cylinder bores (12, 13, 133 to 136) of the corresponding diameter and sealing means (14, 15) are provided between the cylindrical outer surfaces of different diameters and the corresponding associated axial cylinder bores (12, 13, 133 to 136).

15. Internal combustion engine according to claim 14, characterized by the fact that the attachments (7, 8) exially next to one another in the direction from the piston (4) one after the other have a first length section (121, 122) with a cylindrical lateral surface with a smaller diameter than the diameter of the piston (4) and a second length section (123, 124) with a cylindrical lateral surface whose diameter is larger than that of the first length section (121, 122).

16. Internal combustion engine nech claim 15, characterized in that the lugs (1,8) axiol next to each other in the direction of the piston (4) away from each other have three longitudinal sections (121 to 126) with a cylindrical lateral surface, the diameter of the critten cm free end of the lugs (1,8) cus formed section (125,126) with cylindrical surface area is again smaller than the diameter of the second section (122,124).

17. Internal combustion engine nech one of claims 1 to 16 or 54, wherein the respective free outer end of the approaches reciel sealed in an axicle cylinder bore limited by an end face formed by the cylinder, axicle cylinder bore corresponding to the exquisite position of the piston during its stroke in the cylinder immersed deeply, without the respective free end face of the attachment being able to reach the end face formed by the cylinder, which defines the cie axicle cylinder bore, so that a space of variable volume is formed in the cylinder bore between the facing end faces, in which the free end is free The end face of each attachment acts to increase the pressure of a fluid volume, characterized in that by means of a valve-controlled supply and discharge of pressure medium to and from the room, preferably by means of non-return valves or pressure-controlled slide valves variable volume in the end axial cylinder bore (12, 15, 135, 126), so that in conjunction with the stroke movement of the piston (4) and its attachments (1,8), a pressure medium pump integrated in the cylinder (1) together with the internal combustion engine with two pressure generators ice power source is formed for a pressure medium operated system.

18. Internal combustion engine according to claim 15 or 16, characterized in that the axicle cylinder bore (135, 124) receiving the second length section (123, 124) of the extensions (1,8) has at least such an axial length that the second length section (123, 124) of the extensions (7 , 8) which, as a piston disc, can perform an exiol stroke depending on the stroke of the piston (4), which is equal to the moximol possible axial stroke of the piston (4) in the cylinder space (9).

19. Internal combustion engine according to claim 18, characterized in that in the axial cylinder bore (133, 134) for the second longitudinal section (123, 124) of the lugs (7, 8) at both ends of the wall of the cylinder (1) penetrating bores (151 to 158), to which or in which controlling valves, preferably non-return valves, pressure-controlled slide valves, or particularly preferably also control or regulatable valves, are assigned or installed, the bores (151, 153, 155, 151) for the outlet and the bores (152, 154, 156, 158) serve for the inlet of a fluid and each pair of bores from an inlet and an outlet bore (151, 152 or 153, 154 or 155, 156 or 151, 158), which preferably opens perpendicularly into the cylinder bore (133, 134) -of the second length section (123, 124), one each , compared to the other spaces in the cylinder (1) tightly sealed space variable volume of the cylinder bore (133, 134) dnet, wherein each of the cylinder bores (133, 134) is divided by the second length section (123, 124) as a separating piston disc tightly into two axially adjacent spaces of mutually variable volume.

20. Internal combustion engine according to one of the other claims, characterized in that the supply and discharge of pressure medium to and from the space of variable volume in the respective axially outer, end-side axial cylinder bore (12, 13 or 135, 136) by the cylinder (1) formed, end face (87, 88) takes place, the valves (22, 23, 24, 25) controlling the pressure medium inflow and outflow preferably being integrated into this face (87, 88) of the cylinder wall.

21. Internal combustion engine according to one of the other claims, that the hydraulic or pneumatic pressure medium is used with the

Cooling cylinder (1), particularly preferably in the area of the internal combustion engine, that is to say the walls around the cylinder space (9).

22. Internal combustion engine according to claim 21, characterized in that the hydraulic or pneumatic pressure medium is fed to the cylinder (1) of the motor with low pressure on the scug side and both exiolic ends of the cylinder (1), so that the pressure medium in each of the end areas of the cylinder (1) is led to pressure medium lines (81, 82), these pressure medium lines (81, 82) preferably being guided with a large surface and cxiol in the longitudinal cylinder wall (100) to the opposite cylinder bottom area, where the pressure medium is valve-controlled via bores and valves (22, 25) in the cxiol-lying R cum variable volume in the enc-side cylinder bore (12, 15 or 155, 156), while the pressure medium with increased pressure (pressure line) from the room changes in the enc-side cylinder bore (12, 15 or 155, 136) via the exhaust valve (22, 24) the cylinder (1) Known immediately axially at the same end of the cylinder end via the outlet (85,86).

23. Internal combustion engine according to claim 22, characterized in that the end face (81, 88) formed by the cylinder wcnc is formed from at least two porollel facing wall regions, which can preferably consist of cylinder wall components lying against one another, the axially outer end wall region being the pressure medium connections to the pressure medium-operated system, while the turnable area, which has to be approved, parallel and much further inside, transfers the suction-side inlet into the pressure medium lines (81, 82), which contains inlet (23.25) and outlet valves (22.24) and that of the other cylinder reference coming on the suction side of the pressure medium lines (81, 82) via the inlet valve (23, 25) into the axially outside, variable end-side space of the cylinder bore (12, 13 or 135, 136).

24. Internal combustion engine yet one of claims 1 to 23 or claim 34, characterized in that the internal combustion engine pre-compressed air or a pre-compressed air-fuel mixture cus a separate, enderweitic compression device (50) and preferably a Lcdes peicher (51) through the inlet openings (2nd ) is supplied.

25. Internal combustion engine according to one of claims 1 to 13 or claim 34, wherein end faces of the attachments each have a compressing effect on a temporarily closed air volume before this air is fed to one of the combustion frames of the internal combustion engine, dc characterized in that the air or an air-fuel Mixture for the filling of the combustion chambers (10, 11) of the engine through the inlet bores (152,154,156,158) into the axial cylinder bore (133,134) of the second longitudinal section (123,124) of the extension (7,8) and in the cylinder bore (155,134) through the The movement of the piston (4) dependent stroke of the second length section (123, 124) and the outlet bores (151, 153, 155, 151) and connecting lines leading to the inlet openings (2) are known.

26. Internal combustion engine according to one of claims 1 to 25 or claim 34, wherein the engine acts through face end faces of its approaches pre-compressing air or air-pulp mixtures, which precompressed is fed to the combustion chambers via the channels in the piston, characterized in that at least one Space, preferably over two or four spaces of variable volume in the cylinder bores (133, 134) of the second longitudinal sections (123, 124) of the lugs (1,8) are used for pre-compression and their pouring holes (151, 153, 155, 157) with the inlet openings (2) in the cylinder wall (100) are connectable.

21. Internal combustion engine according to claim 26, d a d u r c h g e k e n n z e i c h n e t, that during a stroke of the piston (4) and the second Längencbschnittes (123,123 of the approach (1,8) each cie two pouring holes (151 and 157 or 153 and

155), which are located on either side of the symmetry plane (Z) and which are assigned to the volume of the cylinder bores (133, 154) which is variable in the respective decreasing volume, are connected together with the inlet openings (2).

28. Internal combustion engine according to one of claims 19, 25 to 27, characterized in that the bores (151 to 158) are assigned valves, which are preferably installed in the bores (151 to 158) or the cylinder longitudinal (100), that at least one part the valves assigned to the bores (151 to 158) are used for manual or cutomatic control or regulation of the combustion chamber filling level and are designed as corresponding control or regulating valves, if necessary, with an exhaust air connection and manual or automatic actuating means are provided.

29. Internal combustion engine according to one of claims 18 or 25, characterized in that the lugs (7, 8) have two longitudinal sections (121 and 123 or 122 and 124), the first longitudinal section (121, 123) having a smaller diameter than the piston (4) and the second length section (122, 124) has a larger diameter than the first length section (121, 122), in which case the respective axially outer, end-side space of variable volume in the axial cylinder bore (133, 134) for increasing the pressure of a hydraulic or pneumatic pressure medium for a serves pressure medium operated system, and this end roum is connected to pressure medium connections (81, 82, 85, 86) and valves (22 to 25) and the axially external, end free end face of the projections (7 , 8), which is also the large end face of the second length cut (123.124), increase the pressure d acts, while the smaller end face of the second length section (123, 124) facing the piston (4) in the adjacent space serves to change the volume of the axial cylinder bore (133, 134), which changes in opposite directions, to pre-compress the air to be supplied to the combustion chambers (10, 11) or the air-fuel mixture to act.

30. Internal combustion engine according to claim 18, wherein the end axial cylinder bore for the pre-compression of the air or an air-croft mixture for the filling of the combustion chambers of the engine is characterized in that the axial cylinder bore (133, 134) is designed with valve-controlled pressure medium inlets and outlets and in Connection with the second length section (123, 124) of larger diameter of the lugs (7, 8) forms a reciprocating piston pump for a pressure medium operated system.

31. Internal combustion engine according to one of claims 2 to 30, characterized in that the internal combustion engine (33), in particular as a free-wheel engine, is used in a pressure medium-operated hydraulic or pneumatic system together with a hydraulic or pneumatic drive unit (46) which can be switched over to engine or pump operation, the drive unit (46) being coupled to an electrically operated, switchable starter-alternator unit (47) with a battery (48), which is used to start the internal combustion engine (33) as a starter (= motor) and otherwise as a generator is switched, with a hydraulic or pneumatic motor (36) and pressure accumulator (40).

32. Internal combustion engine according to one of claims 1 to or claim 34, d a d u r c h g e k e n n z e i c h n e t that the piston (4) ice free piston, that is, without a direct mechanical drive connection in the form of a direct linkage to mechanical transmission members.

55. Internal combustion engine according to one of claims 1 to 51 or claim 54, wherein the motor is axially via a directly articulated mechanical transmission element (piston rod) in direct mechanical drive connection, d a d u r c h g e k e n n z e i c h n e t, that the internal combustion engine oxiel on both sides in mechanical drive connection is via articulated mechanical transmission links.

54. V internal combustion engine, in particular free-piston engine, with at least one cylinder (1), with a piston (4) which is movable and sealed and which is guided and guided in the cylinder space (9) and which can axially stroke movements, with cylindrical projections (1,8) on the piston (4), which extend away from the piston (4) on both sides in the exact direction and at least partially have a smaller diameter than the piston (4), the lugs (1,8) at least partially in axial cylinder bores (12, 15) guided and partially sealed in, with combustion chambers (10, 11) in the cylinder (1), which on the one hand and parts of the surfaces of the piston (4) and its approaches (7,8 ) are formed and delimited on the other hand, the surfaces delimiting the combustion chambers (10, 11) being formed in particular by surfaces narrowed on the end face (5 and 26 or 6 and 27), in the longitudinal wall of the cylinder (100) arranged inlet openings (2) for air or air / fiber mixtures and with outlet openings (3) for combustion gases arranged in the longitudinal wall of the cylinder (100), depending on the position of the piston (4) with its lugs (7,8) Outlet openings (3) can be opened or closed respectively with Konclen (18,19) inside the piston (4) and its approaches (7,8) for the passage of gases such as air or air-fuel mixtures, whereby these channels (18, 19) are connected to bores (20, 21) in the lateral surfaces (101, 102) of the lugs (7, 8), the channels (18, 19) the piston interior and the interior of both lugs (1,8) take, are constantly in open connection with each other and can be brought into open connection with inlet openings (2) and the channels (18, 19) can also be brought into or through open holes (20, 21) to the combustion chambers (10, 11) the axial cylinder bore openings (12, 13) can be closed, characterized in that that the channels (18 and 19) are in permanently open connection to the inlet openings 2, that the channels (18, 19) are connected to openings (90 and 91) in the peripheral surface (80) of the piston (4), wherein these openings (90 and 91) in the central axial region of the piston 4 and preferably symmetrical to the plane of symmetry (K) of the piston (4) have an axial extent of the openings (90, 91), or of the inlet openings (2) or at least one recess (eg groove) between the piston core surface and the cylinder longitudinal wall (100), which extends from the cylinder axis (AA) with a length of approximately 15 mm in the axial direction, which corresponds to the length of the stroke of the piston (4), the plane of symmetry (K) preferably in the middle of the length of the openings (50,91) or the recesses in the outer surface of the piston (4) or rather the plane of symmetry (Z) preferably in the middle of the length of the inlet openings (2) or The exceptions in the circumference surface of the cylinder chamber (9), the rapid inlet openings (2) in the longitudinal cylinder wall (100) are arranged in the region of the plane of symmetry (Z) of the cylinder (1) perpendicular to the longitudinal axis (A-A) such that the outlet openings ( 3) for each of the two combustion chambers (10 or 1 1) assigned to one of the piston length halves (401 or 402) are separated from each other and each in the area of a square at a distance (b) to the plane of symmetry (Z ) of the cylinder (1) arranged rodiol plane (Z1 or Z2), and that the bilateral distances (b) of the outlet openings (3) to the plane of symmetry (Z) of the cylinder (1) are set so that the inlet openings (2) then via the openings (90, 91), channels (18, 19) and the bores (20 or 21) assigned to the one piston length half (401 or 402), the combustion chamber (10 or 11) and the outlet openings (5 ) can enter into open flow connection if the end face (6 or w. 5) the other piston length half (402 or 401) in the vicinity of the end face inner surface (21 or 26) of the cylinder space (9) which is assigned to it.

25. Internal combustion engine according to claim 34, d a c u r c h g e k e n n z e i c h n e t, that the openings (90,91) to each other and to the cylindrical axis (A-A) porollel Hegende

Elongated holes are the center of their axial extension parallel to the axis (A-A) in the piston symmetry plane (K).