WO2002057607A1

WO2002057607A1 - Internal combustion engine

Info

Publication number: WO2002057607A1
Application number: PCT/DE2002/000061
Authority: WO
Inventors: Jörg ARNOLD
Original assignee: Ip2H Ag
Priority date: 2001-01-19
Filing date: 2002-01-10
Publication date: 2002-07-25

Abstract

The invention relates to an internal combustion engine comprising a piston (2), particularly a reciprocating piston, which is arranged inside a preferably cylindrical cavity (1) in a manner that permits it to move in a to and fro manner. The piston (2) and the cavity (1) define a combustion chamber (3), and the piston (2) is coupled to a shaft (4), particularly a crankshaft, for driving the shaft (4). The inventive internal combustion engine is designed with the aim of increasing the work output and delivery of torque. To this end, at least one sleeve (5), which can be displaced in a to and fro manner inside the cavity (1), is arranged between the piston (2) and the inner wall of the cavity (1). The sleeve (5) or sleeves is/are coupled to the shaft (4). The sleeve (5) or sleeves is/are driven by the shaft (4) with a maximum speed relative to the cavity (1), whereby this speed is less than the maximum speed of the piston (2) relative to the cavity (1). Finally, the sleeve (5) or sleeves and the piston (2) move essentially in phase.

Description

"Engine"

The invention relates to an internal combustion engine with a piston, in particular a reciprocating piston, which is arranged such that it can be slid back and forth in a preferably cylindrical cavity, the piston and the cavity defining a combustion chamber and the piston being coupled to a shaft, in particular a crankshaft, for driving the shaft.

Internal combustion engines of the type mentioned are known from practice and exist in a wide variety of embodiments. The known engines are operated with any fuels such as gasoline or diesel or alternative fuels. The known engines are used, for example, in the motor vehicle sector.

The utilization of energy or real work of such internal combustion engines is limited by the technical construction which has been customary to date. The limiting factors are the structurally specified power and torque output. The power output P and the torque D, without taking into account the combustion chamber-dependent and speed-dependent influence on the chemical transport and reaction phenomena of fuel combustion, can be approximated by the simple relationships between the design parameters such as effective piston area F _κ , stroke length I, crankshaft speed n, crankshaft eccentricity d and average working pressure p _{m can be} described. The displacement volume V _{H is} calculated as follows: V _H = F _κ I, where P = K, F _κ I np _m and D = K ₂ p _m F _κ d. In particular, the piston speed v _κ with the crankshaft speed n, the crankshaft eccentricity d and the stroke length I have the following relationship: v _{K max} = K ₃ 1 n d. KK ₂ and K ₃ are suitable proportionality factors.

The energy and power balance of reciprocating internal combustion engines of current modern designs is split on average into 30% engine active power yield, 10% frictional work power and pump work power losses, 35% combustion gas expansion work power losses - Exhaust losses - and 25% heat dissipation through cooling. The simple view is that the power and torque output is limited by the thermal and mechanical strength of the engine design.

The two main limiting factors are set out below:

a) This is initially the maximum possible cooling or heat removal from the combustion chamber surfaces. Insufficient heat dissipation leads to fatigue and destruction of the construction materials, especially on the cylinder heads or the intake and exhaust port and valve constructions and on the reciprocating piston combustion chamber surface.

b) The second main factor is the lubricant or lubricant resistance. If the piston stroke speed is too high, the sliding or Lubricant film between the cylinder liners and the reciprocating piston and thus to destroy the sliding surfaces.

These two main limitations of previous engine designs also limit the thermodynamic efficiency η = (T ₂ - T ^ / T _2. This is due on the one hand to the maximum working temperature T _{2 of} the working medium or the combustion gas atmosphere, depending on the cooling capacity and the thermal compatibility of the construction material, with maximum compression or Maximum pressure of the combustion gases On the other hand, this is due to the minimum working temperature T., the combustion gas atmosphere with maximum gas expansion in the combustion chamber.

Thereby, the thermodynamic efficiency η due to the minimum working temperature T. is inversely related to the working power yield ΔP = Δ (p _m V _H ) of the engine, because the lowest possible minimum working temperature T ^ requires the greatest possible gas work expansion and thus a large piston stroke length, which again the speed n of the motor and thus the power The yield is limited in order not to exceed the critical maximum piston stroke speed v _{κ max} for the tear-off of the sliding film. An alternative, simple enlargement of the effective piston area with a constant displacement or cavity volume to reduce the piston stroke speed or to increase the speed and increase the power output up to the critical piston stroke speed is only possible up to a certain limit, since then other limiting problems, such as size restrictions of the engine, too large moving piston masses or excessive acceleration work losses, problems of the combustion chamber geometry with influence on the combustion, too small combustion chamber cooling surfaces in relation to the combustion chamber volume and other problems occur. In previous modern reciprocating piston internal combustion engines, the ratio between the piston stroke length and the diameter of the effective piston area has already been optimized and exhausted with the approximate ratio of almost 1: 1.

Reciprocating internal combustion engines are known as the distant prior art, in which the working reciprocating pistons run in movable sleeves which serve as control slides in inlet and outlet slots for the inlet of a fuel gas mixture and for the outlet of combustion gases. The two best-known constructions by Charles Y. Knight or Peter Burt together with James MC.Collum consist of two cylindrical sleeves running against each other and one inside the other, which swing up and down in a straight line at half the crankshaft speed, driven by a separate eccentric shaft become. In the case of Burt and MC.Collum, the design consists in particular of a single cylindrical sleeve that performs a combined lifting and rotating movement and is directly driven by an eccentric shaft oriented perpendicular to the lifting movement. Due to the condition that half of the crankshaft speed is required to drive these designs, the moving sleeves cannot be driven directly by the crankshaft.

Both constructions have in common that the control effect only by two separate superimposed movements, e.g. B. can be achieved by the opposite individual movement of each "Knight swing valve" or by the superimposed lifting and rotating movement of the rotary valve from Burt and MC.Collum. These known constructions of moving sleeves, in which the working piston moves, are used exclusively for Engine control and not increasing the maximum possible piston stroke speed, their mode of operation even reduces the maximum possible piston stroke speed, since the sleeve movement is sometimes even opposite to the reciprocating piston movement and does not run in phase with it.

The present invention is therefore based on the object of specifying an internal combustion engine of the type mentioned at the outset in which the work output and torque output are increased.

According to the invention, the above object is achieved by an internal combustion engine having the features of patent claim 1. According to this, the internal combustion engine is designed in such a way that at least one sleeve which can be pushed back and forth in the cavity is arranged between the piston and the inner wall of the cavity and that the sleeve or sleeves is or are coupled to the shaft such that the sleeve or the sleeves are driven by the shaft at a maximum speed relative to the cavity which is less than the maximum speed of the piston relative to the cavity, and that the sleeve or the sleeves and the piston move substantially in phase.

In a manner according to the invention, a new working principle of an internal combustion engine is provided here, which solves the above object in a surprisingly simple manner. In this case, the piston is not guided in liners which are fixed towards the engine block, as was customary hitherto. Rather, the piston is guided in a moving sleeve in order to significantly increase the maximum permitted piston stroke speed or the permitted piston stroke length and consequently the thermodynamic efficiency. The moving sleeve or sleeves are guided in the cavity. It is essential that the rifle or the sen is or are coupled to the shaft such that the sleeve or sleeves are driven by the shaft at a maximum speed relative to the cavity that is less than the maximum speed of the piston relative to the cavity. As a result, the speed of the piston relative to the cavity can be increased compared to known designs without lubrication deficits occurring. All parts moving relative to one another move at a maximum speed that is below a speed at which lubrication problems can occur. The piston speed is quasi transformed to a higher speed than usual by means of the sleeve or the sleeves. In order not to produce excessive relative speeds of the moving parts to one another, the sleeve or the sleeves and the piston move essentially in phase with one another.

This special design provides an internal combustion engine and, quite generally, a heat engine, in which the power and torque output dimension that has been achievable to date has been increased or, alternatively, a significantly lower fuel consumption has been achieved with a power and torque output dimension than previously customary engine designs. The reason for this is a significantly increased thermodynamic efficiency. More specifically, the maximum working temperature T _{2 is} increased and the minimum working temperature TA _{, of} the engine is lowered. As a result, the thermodynamic efficiency is significantly increased.

In the present invention, the piston can move in a sleeve with the maximum possible piston stroke speed v _{K max} . The sleeve or drag sleeve itself can in turn be moved in the cavity or cylinder block with the maximum permissible running speed. The piston thus slides in the sleeve, which in turn slides in the engine block cylinder. If the same maximum movement speed is permissible for the sleeve and the piston and the sleeve and the piston are essentially aligned or in phase in their movement, the piston can in the theoretical limit case without destruction with twice the piston speed v _{κ max} as in previous Engine designs are running. The piston, the sleeve and the cavity form quasi telescope segments that can slide into one another or be pulled out and pushed in according to the telescope principle.

As a result, the piston stroke length I can be doubled at the previously customary and possible engine speeds in the limit case and the additional gas work expansion can be reduced to half the average working end pressure of previously customary engine designs, which correlates with a significantly lower minimum working temperature T. With twice the volume, there is almost half the pressure.

In the above formula description, this leads to an increase in the piston stroke lengths I to 200% and a decrease in the mean working pressure p _m to 75% and thus to an increase in the power yield P to 150% for the power and torque yield at a constant rotational speed. The doubling of the piston stroke length is achieved constructively by doubling the crankshaft eccentricity d, as a result of which the torque yield D is increased by 100% to 200%.

The increase in engine performance is even accompanied by a reduction in the thermal load on the engine, since the dwell time of the combustion gases remains unchanged in the expansion work cycle of the engine at a constant rotational speed, but the mean temperature of the combustion gas atmosphere and thus the temperature gradient for heat transfer to the combustion chamber surface because of the greater real work done and the increase in the combustion chamber surface due to the constant piston surface and cylinder head surface or cavity end surface has not doubled, but rather grows disproportionately with the increase in the piston stroke.

The increased power yield results exclusively from the increase in the thermodynamic efficiency through the lowering of the minimum working temperature T, because of the constructionally enabled increased combustion voltage gas-work expansion.

Specifically, several bushings and the piston could be moved telescopically in the cavity. This enables a particularly controlled and efficient increase in the maximum piston speed. In any case, the sleeve or the outermost sleeve is guided in the cavity.

In a particularly advantageous manner, the bushing or the bushing closest to the piston is dimensioned such that the piston is located within the bushing or the bushing closest to the piston during its entire back and forth movement. This ensures particularly safe operation of the engine.

Specifically, the inner wall of the cavity could be formed by a sliding bush which is inserted into an engine block or is integrally formed in the engine block. This results in a particularly secure mounting of the rifle or the outermost rifle.

The sleeve or sleeves and / or the sliding sleeve could be made of metal, preferably a gray cast iron material, a steel-aluminum alloy - e.g. Duralumin - or titanium, or an oxide ceramic material. The sleeve or the sleeves could have a wall that is only a few millimeters thick and just sufficiently stable under combustion pressure, for example a cylinder wall, in order to keep inertial forces or the necessary mass accelerations low. Here are light but sufficiently strong materials such as Cheap duralumin or titanium. Alternatively, a gray cast iron material could be used for the slide bush and the bush or bushes, whereby no sealing rings - piston rings or oil wiper rings - are required between the two components, since the thermal expansion behavior is the same.

The sleeve or the sleeves and / or the sliding sleeve could have a surface coating which, for example, consists of a metal oxide, a Metal carbide, could consist of pure carbon - diamond - or chrome. This is based on the respective application and the respective requirement for abrasion resistance. The use of low-heat and high-temperature-resistant oxide ceramics would be advantageous and conceivable in particular for the sliding bush or drag bush guide bushing in connection with high-temperature motor designs.

With a view to improved oil sliding lubrication, sealing and guide rings, preferably piston rings or oil scraper rings, could be provided between the sleeve or the sleeve closest to the sliding sleeve and the sliding sleeve. Such sealing or guide rings could also be provided between the bushing or the bushing closest to the piston and the piston, or alternatively or additionally, between the bushings. The sealing or guide rings could be in preferably radial inner grooves of the slide bush or in outer grooves of the bush or the bush closest to the slide bush and / or in inner or outer grooves of the bushes and / or in inner grooves of the bush or the bush closest to the piston or in outer grooves of the Be arranged piston.

The sleeve or the sleeves could each have a guide pin with an axis. The guide pin could each be arranged on the lower inner edge of the sleeve or the sleeves. The axis could be arranged parallel to a piston pin axis. Here, a preferably roller-bearing bush connecting rod could be arranged with one end on the or each guide pin. At its other end, the bushing connecting rod could be coupled to an eccentric element of the shaft.

In other words, the piston can be designed with a piston pin and a piston pin roller bearing and can be connected to the eccentric pin of the crankshaft by means of a connecting rod which is also roller-mounted. A cylindrical bushing could have a guide pin on the lower inner edge, the pin axis of which is aligned parallel or coaxially to the piston pin axis. One may sit on this bush pin roller bearing connecting rod. The bushing connecting rod may also have a roller bearing at the end remote from the bushing and is seated on an eccentric element of the shaft.

This eccentric element, which could also be a simple eccentric pin in the case of a non-in-line engine, for example a single-cylinder engine or radial engine, is preferably cranked or bent twice or several times, so that it has at least two coplanar-guided connecting rods, the bushing connecting rod and a piston connecting rod, can lead with different eccentricity and possibly different angle of rotation or can lead past each other. The shaft therefore carries two connecting rods on a cranked eccentric element of the shaft between two shaft bearings, for example, for in-line engines for one cylinder unit each.

The bushing connecting rod sits on the eccentric element section with the smaller eccentricity. The piston connecting rod sits on the other eccentric element section with the greater eccentricity. More specifically, each sleeve eccentric element section assigned to a sleeve has a smaller eccentricity than a piston eccentric element section assigned to the piston. In concrete terms, the piston eccentric element section could have twice the eccentricity as the sleeve eccentric element section of the sleeve closest to the piston.

When realizing several bushes, the bush eccentric element sections of the bushes could each have an ever smaller eccentricity towards the inner wall of the cavity, as seen from the piston. A sleeve eccentric element section of a sleeve located further inside therefore has a greater eccentricity than a sleeve eccentric element section of a sleeve located further outside.

The relative movement of the sleeve or sleeves relative to the piston is determined by the different eccentricity and angular position of the two eccentric element sections of the shaft cranked against one another. Here, the The sleeve eccentric element section or the sleeve eccentric element sections and the piston eccentric element section have the same angle of rotation position. In practice, this has proven to be the most favorable combination in combination with the double eccentricity for the piston eccentric element section in comparison with the sleeve eccentric element section. The piston is guided on average at twice the absolute speed of the sleeve, while the sleeve against the sliding sleeve or against the cavity has the same relative speed as the piston against the sleeve.

The bushing connecting rod could be mounted eccentrically in each bushing. The piston connecting rod could be centered or centered in the piston or it could be eccentric, depending on the particular application. If the bushing connecting rod is mounted eccentrically and the piston connecting rod is mounted centrally in the piston, both connecting rods can safely move past each other on their coplanar trajectories. However, an embodiment of the invention is also conceivable with two connecting rods arranged eccentrically to the piston or the sleeve.

With regard to a particularly simple embodiment of the internal combustion engine, at least one inlet and / or at least one outlet passage could be formed in the wall of the cavity, so that the sleeve or the sleeves can be used as a valve element for the passage or passages. Specifically, the moving bushing or the moving bushings can additionally be used as a preferably cylindrical valve slide or tubular swing slide for the fresh air inlet and the combustion gas outlet via passages - for example slots or annular gaps. As a result, the use of conventional cylinder head constructions with the previously complicated inlet and exhaust valve constructions and with the entire pending valve train such as camshafts, camshaft bearings and camshaft drives or camshaft drives - spur gearboxes - can be dispensed with in the invention. The annular gaps that are used, for example, ensure a smooth and streamlined gas flow and consequently good gas mixture filling levels in contrast to valve ring gaps common today with pronounced angles and corners.

The passage or the passages can be formed in the concrete in the area of the sliding surface of the sleeve or the sleeves or in the sliding sleeve. More specifically, the passages could open laterally in the engine block head in the slide bush or drag bush guide bush and not, as was previously the case, in the engine block head end or in the previously common cylinder head.

The inlet and outlet passages can - in the case of several passages for inlet and outlet in each case - be formed separately in the same cylinder circular section plane with respect to a circular-cylindrical cavity or a circular-cylindrical sliding bush.

Specifically, the outlet passage or outlet passages could be formed substantially at one end of the cavity and the inlet passage or inlet passages essentially at the other end of the cavity. The exhaust passage or the exhaust passages to the shaft could be just above the piston combustion chamber surface at the bottom of the piston dead center, and the intake passage or the intake passages to the cylinder head end could be approximately half the length of the slide bushing guideway. Intake passages and exhaust passages can therefore be conveniently separated widely, which avoids the high thermal alternating loading of the intake passage and exhaust passage partitions in conventional cylinder head designs.

For optimal functioning of the internal combustion engine, the bushing or the bushings also each have at least one outlet passage.

In concrete terms, the passage or passages could be designed as a slot or slots or as an annular gap or annular gaps.

In a thermally particularly favorable embodiment, the combustion chamber could be in the area away from the piston. The internal combustion engine can even be realized without a separate cylinder head with a cylinder block made of highly heat-resistant material, such as gray cast iron, which completely closes off the combustion chamber at the top. This in turn has a significant influence on the increase in the thermodynamic efficiency, since now the previously very temperature-sensitive or less heat-resistant cylinder head designs can be avoided. Therefore, significantly higher maximum combustion temperatures T ₂ can subsequently be used in order to further increase the thermodynamic efficiency.

The naturally higher mass of, for example, highly heat-resistant gray cast iron is not important for the engine design, since on the other hand, the entire complicated cylinder head construction previously used, with the associated valve drive on the crankshaft side, can be avoided. In addition, of course, there are also significant economic advantages in production, such as a much more cost-effective production of engines from significantly fewer components.

Since the cylinder head end now does not include any temperature-critical components, a much higher combustion chamber temperature can be permitted, especially in the hottest area of the combustion chamber. The temperature of the cylinder head ends may even be brought to the limit of the heat resistance of the cylinder head material, since the invention is highly knock-resistant due to the lack of hot exhaust valves of conventional cylinder head designs and the possibility of a centrally placed spark plug. This can be used for a substantial increase in the combustion chamber temperature T ₂ and thereby for a substantial increase in the thermal efficiency.

With regard to a particularly reliable supply of fresh air into the cavity, a conveying device for supplying fresh air could be provided. Such a conveyor could be a compressor unit of the engine, for example a roots loader, spiral loader, rotary piston loader, screw loader or mechanical rotary loader. Fresh air could be pressed into the combustion chamber, which could lead to a further flushing out of the residual combustion gases through the still open outlet passages into an outlet duct and to additional cooling of the inner combustion chamber surfaces by the fresh air flow being passed through.

There are now various possibilities for advantageously designing and developing the teaching of the present invention. For this purpose, reference is made to the subordinate claims, on the one hand, and to the following explanation of a preferred exemplary embodiment of the internal combustion engine according to the invention with reference to the drawing. In connection with the explanation of the preferred embodiment with reference to the drawing, generally preferred configurations and developments of the teaching are also explained. In the drawing shows the only one

Fig. In a schematic representation, the embodiment of an internal combustion engine according to the invention.

The only FIG. 1 shows an internal combustion engine with a piston 2, which is arranged so that it can be pushed back and forth in a cylindrical cavity 1. The piston 2 and the cavity 1 define a combustion chamber 3. The piston 2 is coupled to a shaft 4 for driving the shaft 4 , Between the piston 2 and the inner wall of the cavity 1, a bush 5 which can be pushed back and forth in the cavity 1 is arranged. The sleeve 5 is coupled to the shaft 4 in such a way that the sleeve 5 is driven by the shaft 4 at a maximum speed relative to the cavity 1 which is lower than the maximum speed of the piston 2 relative to the cavity 1. The sleeve 5 and the piston 2 essentially in phase.

Specifically, the inner wall of the cavity 1 is formed by a sliding bush 6, which is arranged in the cavity 1. The sleeve 5 has a guide pin 7 which is arranged on the lower inner edge of the sleeve 5. A bushing connecting rod 8 is arranged with one end on the guide pin 7. The bushing connecting rod 8 is coupled at its other end to an eccentric element 9 of the shaft 4. The eccentric element 9 is cranked or double kinked.

The sleeve eccentric element section 10, which is assigned to the sleeve 5, has a smaller eccentricity than a piston eccentric element section 11 assigned to the piston 2. More specifically, the ratio of the eccentricities is 1: 2.

In the wall of the cavity 1, an inlet passage 12 and an outlet passage 13 are formed in a slit shape. The bush 5 thus serves as a valve element for the passages 12 and 13. The bush 5 also has an outlet passage 13.

The combustion chamber 3 is closed in the area 14 remote from the piston. Inlet and outlet valves of a conventional internal combustion engine are dispensed with. A piston connecting rod 15 is provided between the piston 2 and the shaft 4. The entire arrangement described above is provided in an engine block 16.

At the top dead center of the sleeve 5, the sleeve 5 closes both the upper inlet passage 12 and the lower outlet passage 13. The sleeve 5 itself has the outlet passage 13 in a cylinder circular section plane, which is just before the bottom dead center of the sleeve 5 is congruent with the outlet passage 13 of the sliding bush 6 or the cavity 1. If several passages 12 and 13 were to be formed here per component, the bushing 5 would also close or release these passages 12 and 13 accordingly. For the sake of simplicity, only one passage 12 and 13 is used as the basis for the description. Shortly before the bottom dead center of the sleeve 5, the outlet passage 13 of the sleeve 5 is closed by the piston 2. At the bottom dead center of the piston 2, both the inlet and outlet passages 12 and 13 are open. The positions of the inlet and outlet passages 12 and 13 are dimensioned such that shortly before the bottom dead center of the sleeve 5 and the piston 2, respectively, the outlet passages 13 are released by the piston 2 and the sleeve 5 passing over them and then only the upper inlet passage 12 is released from the sleeve 5.

In the control according to the invention - slot control or swing slide control - there is a single-tube swing slide control in which the swing slide, that is to say the sleeve 5, is driven directly by the shaft 4 at the shaft speed and only executes a simple linear movement, that is to say not in the case of previous single-tube swing slide valves. Constructions must perform a superimposed movement. This is made possible according to the invention in that the piston 2 is also used for the passage control.

The described construction undergoes the following movement and functional sequence during operation. During the rotational movement of the shaft 4 - starting from the top dead center of the piston 2 - the piston 2 in the bush 5 lowers and the bush 5 is dragged at half the piston speed. All inlet and outlet passages 12 and 13 are closed.

As the piston 2 and the sleeve 5 approach bottom dead center, the outlet passages 13 of the sleeve 5 and the sliding sleeve 6 begin to overlap. The outlet passage 13 of the sleeve 5 is just still closed by the piston 2 running over it. In the further course of motion - shortly before the bottom dead center of the piston 2 - the piston 2 now releases the outlet passages 13 and the combustion gas, which is still under pressure, can expand into the outlet channel via the outlet passages 13. In the further course of motion, the bush 5 now also releases the upper inlet passage 12 shortly before its bottom dead center and fresh air can be pressed into the combustion chamber via a conveying device, which leads to a further flushing out of the combustion residual gases through the still open outlet passages 13 in the FIGS Exhaust duct and additional cooling of the inner combustion chamber surfaces by the fresh air flow passed through.

The use of a conveyor for fresh air loading does not impair the efficiency of the engine, since on the one hand the entire conventional energy-consuming valve drive is saved and on the other hand the suction power to be applied by the conventional naturally aspirated engine is saved. It should also be noted that each naturally aspirated motor also represents its own suction pump for mixture intake, and that a naturally aspirated motor viewed as a suction pump unit alone, due to its dual design function as a suction pump and as an internal combustion engine, is usually not optimized in terms of its efficiency. The use of a specialized, separate conveying unit or separate conveying device which is optimized with regard to its efficiency therefore leads to a further increase in the efficiency of the entire machine or of the entire internal combustion engine.

In the further course of movement, the bush 5 and the piston 2 pass over their bottom dead centers and rise again, the outlet passages 13 which were opened first being closed again. Now the fresh air pressure of the conveying device can build up in the combustion chamber in the further movement sequence until the further sleeve movement also closes the inlet passage 12. The further movement sequence is then the compression cycle up to the top dead center of the piston 2.

The piston 2 and the sleeve 5 have only a slightly different angle of rotation position or even have the same angle of rotation position. A different angle of rotation position can be achieved constructively by rotating the crank of the eccentric element 9. When using a different In the angular position, advantageously minimized internal wear of the bushing 5 is to be expected at the top dead center of the piston race because the sliding movement does not come to a standstill at the top dead center.

Within this cycle, the fuel is injected directly into the combustion chamber. After the piston 2 has passed top dead center, the combustion gas mixture is ignited and the combustion cycle or expansion work cycle begins. The invention thus represents a two-stroke pipe valve-valve-controlled engine with drag bushes and compressor fresh air loading and direct fuel injection.

As a result, this engine design can achieve twice the power output compared to conventional comparable four-stroke engine designs at the same previously usual speed in the theoretical limit case, or a significantly smaller size and engine mass can be achieved with comparable power output. Specifically, the smaller possible displacement geometries of the invention make it possible to compensate for the mass to be accelerated, which consists of working pistons, drag bushes and the connecting rods, and bring them to the previously usual level.

With the mode of operation of the invention described so far, the improvement in the thermodynamic efficiency η can be roughly estimated. The typical minimum working temperature T, the combustion gas atmosphere in conventional reciprocating piston internal combustion engines is between approx. 700 ° Celsius and approx. 1000 ° Celsius. An average of approx. 800 ° Celsius is used for this estimate. The average maximum working temperature T _{2 of} the combustion gas atmosphere is around 1300 ° Celsius on average in conventional engine designs. The thermodynamic efficiency of previous reciprocating piston internal combustion engines is then on average approx. Η = 0.38, taking into account the pumping and frictional work performed by the engine.

Under the roughly simplified assumption that a reduction in the motor head cooling or an increase in temperature of the motor head achieved thereby also an increase in the maximum working temperature T _{2 of} the combustion gas atmosphere by up to 200 ° Celsius, the second inventive measure, i.e. avoiding engine head control by means of a drag bush control, leads to an increase in the thermodynamic efficiency by 24% to η = 0.47. Together with the first inventive measure described, the doubling of the expansion volume, the minimum working temperature JA in adiabatic approximation - adiabatic exponent χ = 0.4 - can be reduced to approximately 600 ° Celsius. As a result, the effect of the invention results overall in an increase in the thermodynamic efficiency of 58% from η = 0.38 to η = 0.6.

This means that the power yield of reciprocating piston internal combustion engines can be increased by approximately 50% with the fuel consumption remaining the same or that the fuel consumption can be reduced by approximately 50% while the power output remains the same. According to the invention, the additional power comes from the substantially better utilization of the combustion gas energy and from the reduction of the heat energy dissipation through cooling.

The thermodynamic efficiency of the invention can be increased even further by the kinetic residual energy of the combustion exhaust gas stream via turbomachines such. B. exhaust gas turbines is used, as is already common. It is estimated that this again leads to an increase in the possible efficiency of such a compound machine by up to 10%. Due to the exemplary construction of the invention described without an independent intake activity for fresh air, an additional turbine unit is not suitable for fresh air loading in the engine starting phase. Such additional turbine units can, however, deliver their power yield of the residual gas energy directly to the crankshaft via a transmission. Overall, an internal combustion engine can be realized with the presented invention, which promises a far higher thermal efficiency and thus alternatively either much higher power and torque yields or a significantly lower fuel consumption with comparable performance yields of today's internal combustion engines.

Claims

Patent claims

1. Internal combustion engine with a piston (2), in particular a reciprocating piston, arranged in a preferably cylindrical cavity (1) so that it can be pushed back and forth, the piston (2) and the cavity (1) defining a combustion chamber (3) and the piston (2 ) is coupled to a shaft (4), in particular a crankshaft, for driving the shaft (4), characterized in that between the piston (2) and the inner wall of the cavity (1) at least one can be pushed back and forth in the cavity (1) Bushing (5) is arranged and that the bushing (5) or the bushings is or are coupled to the shaft (4) in such a way that the bushing (5) or the bushings through the shaft (4) at a maximum speed relative to the cavity ( 1) is or are less than the maximum speed of the piston (2) relative to the cavity (1), and that the sleeve (5) or the sleeves and the piston (2) move essentially in phase.

2. Internal combustion engine according to claim 1, characterized in that a plurality of bushes and the piston are telescopically movable in the cavity.

3. Internal combustion engine according to claim 1 or 2, characterized in that the sleeve (5) or the closest to the piston sleeve is dimensioned such that the piston (2) during its entire back and forth movement within the sleeve (5) or the bush closest to the piston (2).

4. Internal combustion engine according to one of claims 1 to 3, characterized in that the inner wall of the cavity (1) is formed by a sliding bush (6).

5. Internal combustion engine according to one of claims 1 to 4, characterized is characterized in that the sleeve (5) or the sleeves and / or the sliding sleeve (6) are made of metal, preferably a gray cast iron material, a steel aluminum alloy or titanium, or an oxide ceramic material.

6. Internal combustion engine according to one of claims 1 to 5, characterized in that the sleeve (5) or the sleeves and / or the sliding sleeve (6) have or have a surface coating.

7. Internal combustion engine according to claim 6, characterized in that the surface coating consists of a metal oxide, a metal carbide, pure carbon - diamond - or chromium.

8. Internal combustion engine according to one of claims 1 to 7, characterized in that sealing or guide rings, preferably piston rings or oil control rings, are provided between the bushing or the bushing closest to the sliding bushing and the sliding bushing.

9. Internal combustion engine according to one of claims 1 to 8, characterized in that sealing or guide rings, preferably piston rings or oil control rings, are provided between the bushing or the bushing closest to the piston and the piston.

10. Internal combustion engine according to one of claims 1 to 9, characterized in that sealing or guide rings, preferably piston rings or oil control rings, are provided between the bushings.

11. Internal combustion engine according to one of claims 8 to 10, characterized in that the sealing or guide rings in inner grooves of the slide bush or in outer grooves of the bush or the bush closest to the slide bush and / or in inner or outer grooves of the bushes and / or in inner grooves the bushing or the bushing closest to the piston or in outer grooves of the piston.

12. Internal combustion engine according to one of claims 1 to 11, characterized in that the sleeve (5) or the sleeves each have or have a guide pin (7) with an axis.

13. Internal combustion engine according to claim 12, characterized in that the guide pin (7) is arranged on the lower inner edge of the sleeve (5) or the sleeves.

14. Internal combustion engine according to claim 12 or 13, characterized in that the axis is arranged parallel to a piston pin axis.

15. Internal combustion engine according to one of claims 12 to 14, characterized in that on the or each guide pin (7) a preferably roller-bearing bush connecting rod (8) is arranged with one end.

16. Internal combustion engine according to claim 15, characterized in that the bushing connecting rod (8) is coupled at its other end to an eccentric element (9) of the shaft (4).

17. Internal combustion engine according to claim 16, characterized in that the eccentric element (9) is cranked.

18. Internal combustion engine according to one of claims 1 to 17, characterized in that each of a sleeve (5) assigned sleeve eccentric element section (10) has a smaller eccentricity than a piston (2) associated piston eccentric element section (11).

19. Internal combustion engine according to claim 18, characterized in that the piston eccentric element section (11) has twice the eccentricity as the sleeve eccentric element section (10) of the sleeve (5) closest to the piston (2).

20. Internal combustion engine according to claim 18 or 19, characterized in that the sleeve eccentric element sections of the sleeves from the piston each have an ever smaller eccentricity towards the inner wall of the cavity.

21. Internal combustion engine according to one of claims 18 to 20, characterized in that the sleeve eccentric element section (10) or the sleeve eccentric element sections and the piston eccentric element section (11) have the same angle of rotation position.

22. Internal combustion engine according to one of claims 15 to 21, characterized in that the bushing connecting rod (8) is mounted eccentrically in each bushing.

23. Internal combustion engine according to one of claims 1 to 22, characterized in that a piston connecting rod (15) is mounted eccentrically in the piston.

24. Internal combustion engine according to one of claims 1 to 23, characterized in that in the wall of the cavity (1) at least one inlet (12) - and / or at least one outlet passage (13) are formed, so that the sleeve (5) or the bushings can be used as a valve element for the passage (12, 13) or the passages (12, 13).

25. Internal combustion engine according to claim 24, characterized in that the passage (12, 13) or the passages (12, 13) in the region of the sliding surface of the sleeve (5) or the sleeves or in the sliding sleeve (6) is or are formed.

26. Internal combustion engine according to claim 24 or 25, characterized in that the inlet and outlet passages (12, 13) - in each case several passages for inlet and outlet - separately in the same cylinder circular section plane with respect to a circular-cylindrical cavity (1) or egg - ner circular cylindrical slide bush (6) is or are.

27. Internal combustion engine according to one of claims 24 to 26, characterized in that the exhaust passage (13) or the exhaust passages substantially at one end of the cavity (1) and the intake passage (12) or the intake passages are essentially formed at the other end of the cavity (1).

28. Internal combustion engine according to one of claims 1 to 27, characterized in that the sleeve (5) or the sleeves each have at least one outlet passage (13).

29. Internal combustion engine according to one of claims 24 to 28, characterized in that the passage (12, 13) or the passages (12, 13) is or are designed as a slot or slots or as an annular gap or annular gaps.

30. Internal combustion engine according to one of claims 1 to 29, characterized in that the combustion chamber (3) in the area remote from the piston (14) is closed.

31. Internal combustion engine according to one of claims 1 to 30, characterized in that a conveying device for supplying fresh air into the cavity (1) is provided.