EP0294369A1

EP0294369A1 - Internal combustion engine

Info

Publication number: EP0294369A1
Application number: EP19870900114
Authority: EP
Inventors: Clemens Kiefer
Original assignee: Weber Hans-Juergen
Current assignee: Weber Hans-Juergen
Priority date: 1986-12-08
Filing date: 1986-12-08
Publication date: 1988-12-14
Also published as: WO1988004359A1

Abstract

Le moteur décrit comporte au moins un cylindre de combustion (11) formé dans un bloc-moteur (14). En amont du cylindre de combustion (3) sont agencées respectivement une chambre de compression (8, 10) pour l'air de combustion et une pour le carburant, lesquelles entourent totalement ou partiellement ledit cylindre (3). La chambre de compression (10) destinée au carburant est partiellement entourée par la chambre de compression (8) destinée à l'air de combustion, deux cylindres de compression (1, 2) étant agencés, en amont de la chambre de compression (8), en série avec une chambr de compression (7) intercalée. La soupape d'échappement (6) du cylindre de combustion (3) est réglée en fonction de la course du piston, de sorte qu'elle se ferme avant que le point mort haut du piston soit atteint. Pour la transmission de puissance, il est prévu un entraînement à plateau oscillant comportant un plateau oscillant sensiblement tronconique portant sur son bord extérieur des bielles (12), lequel plateau est monté sur le bloc moteur (14) au moyen d'un joint de cardan fixé au centre sur l'extrémité large, et est pourvu, du côté étroit, d'un maneton incliné de vilebrequin, maintenu dans un alésage centré, et fixé dans un volant d'inertie solidaire de l'arbre.The engine described comprises at least one combustion cylinder (11) formed in an engine block (14). Upstream of the combustion cylinder (3) are respectively arranged a compression chamber (8, 10) for the combustion air and one for the fuel, which completely or partially surround said cylinder (3). The compression chamber (10) for the fuel is partially surrounded by the compression chamber (8) for the combustion air, two compression cylinders (1, 2) being arranged, upstream of the compression chamber (8 ), in series with an interposed compression chamber (7). The exhaust valve (6) of the combustion cylinder (3) is adjusted according to the stroke of the piston, so that it closes before the top dead center of the piston is reached. For power transmission, a swash plate drive is provided comprising a substantially frustoconical swash plate carrying on its outer edge connecting rods (12), which plate is mounted on the engine block (14) by means of a universal joint. fixed in the center on the wide end, and is provided, on the narrow side, with an inclined crankshaft crankpin, held in a centered bore, and fixed in a flywheel secured to the shaft.

Description

Internal combustion engine

The invention relates to an internal combustion engine according to the preamble of claim 1.

It can be assumed that the currently high oil production rates will lead to a shortage of fuels in the foreseeable future, so that the use of internal combustion engines with low fuel consumption in the short term and medium or low. In the long term, the use of alternative fuels such as methanol or hydrogen will become indispensable, which can be obtained from water by splitting with the help of nuclear fusion energy. The already very high environmental impact, to which the global star increased road traffic makes a significant contribution, requires a short-term reduction in pollutant emissions from motor vehicle engines.

A significant improvement in the properties of today's petrol and diesel engines, which have been largely optimized, can no longer be expected. A noteworthy reduction in the fuel consumption of diesel engines seems at most possible when using ceramic material, which would allow an increase in the mean wall temperatures and thus a reduction in losses caused by cooling. Ceramic materials are known to be susceptible to high impact loads stung and large jumps in temperature. However, both loads occur to a high degree in the known explosion engines, which is why, at least so far, the development of a functional ceramic engine has not been successful and cannot be expected on the basis of diesel or gasoline engines.

The object of the present invention is to create an internal combustion engine which, on the one hand, causes no or at least substantially reduced impact load and, on the other hand, the operation of which brings with it significantly smaller temperature jumps than the known engines.

This object is achieved by an internal combustion engine having the features set out in patent claim 1, in which the functional features of a compressor, a steam engine and an internal combustion engine are combined with one another in an ideal manner, with the use of any liquid as a further essential advantage and gaseous fuel is possible, ie the machine can also be operated in pure gas mode with hydrogen, the likely energy source of the future. It also enables energy storage, so that, for example, when used as a drive for motor vehicles by recovering braking energy, a high acceleration capacity, easy starting and a considerable reduction in the size of the transmission is possible.

Further advantageous embodiments of the invention result from; the subclaims. The invention is explained below with reference to the accompanying drawings, for example. Show it

Fig. 1 shows the schematic representation of the function of a

Internal combustion engine according to the invention. FIG. 2 shows a schematic sectional illustration through a swash plate arrangement according to the invention

The internal combustion engine shown in the drawing consists of a combustion cylinder 3 formed in an engine block 14, into which the fuel and the combustion air are introduced under pressure. De combustion cylinder 3 are a pressure chamber 8 the combustion air and a pressure chamber 10 for the fuel upstream, which completely or partially enclose the combustion cylinder 3 or otherwise i direct heat exchange with the combustion cylinder 3, so that the heat generated by the combustion directly under preheating and if necessary - when using liquid fuel - evaporation of the fuel or the air is recovered. In the case of the illustrated embodiment, the pressure chamber 10 projects for the fuel with its essential part into the pressure chamber for the expansion air 8 and is thus enclosed by this, so that for safety reasons only indirect heat exchange takes place.

The compression of the combustion air takes place in two stages, since the pressure chamber 8 for the combustion air is preceded by two compression cylinders 1 with an intermediate pressure chamber 7. It he the combustion itself also follows in two stages in such a way that a (low pressure) axle combustion cylinder 4 is arranged downstream of the combustion cylinder 3 via a further pressure chamber 9.

The control of the gas and air flows between the pressure chambers 7, 8,

9, 10 and the working cylinders 1, 2, 3, 4 is carried out with the aid of rotary slide valves, slide valves or mushroom valves, the inlet valves being provided with the reference number 5 and the exhaust valves with the reference number 6 throughout the drawing. In operation, the outlet valve 6 of the combustion cylinder 3 is expediently controlled in dependence on the piston stroke in such a way that the valve closes prematurely before the top dead center position of the piston is reached, so that the same occurs when the top dead center position is reached Pressure as in the pressure chambers 8, 10- ^' for the combustion air. there is fuel. The power regulation or Energy storage is expediently carried out by changing the valve opening times or the passage cross sections in such a way that more gas mass is conveyed by compression into one - or more - pressure chamber (s) than it (s) releases for combustion and expansion.

The pressure chambers 7, 8, 9, 10 can, for the purpose of exhaust gas energy recovery, be connected to a water reservoir (not shown), from which, if necessary, water flows into one or more of the pressure chambers 7, 8, 9,

10, is promoted, which is mixed with the gases flowing into the engine cylinder (3, 4) after evaporation. Here, the engine block can be provided with pressure channels or pressure lines for guiding cooling water, cooling or return air or fuel, so that the steam formed. the preheated gas is mixed with the gas flowing into the engine cylinder 3, 4 and thus the stored heat can be recovered.

For power transmission - see Fig. 2 is a swash plate drive with a substantially frustoconical, on its outer Ran connecting rod 12 swash plate 13 is provided, which is mounted on the engine block 1 by means of a wide end centrally fastened universal joint 15 and on the narrow side with one in one Centered bore 19 is provided inclined crank pin 18 which is fixed in a shaft 17 firmly connected to the shaft 16.

During operation, compression and expansion take place in two stages in the compression cylinders 1, 2 and 2 respectively. Engine cylinders 3, 4, the work rooms in the corresponding time period via the inlet valves 5 or respectively. the outlet valves 6 are connected to the pressure vessels or to the outside air. The fresh air is drawn in through the (large) compressor cylinder 1, which compresses the air with the compression ratio and presses it into the pressure chamber 7. The air thus pre-compromised passes from the pressure chamber 7 into the small compressor cylinder 2, in which it is further compressed with the compression ratio and pressed into the pressure chamber 8. To avoid work losses, the inlet into the cylinder only begins when the pressure in the work space has dropped to the value of the intake pressure. In a corresponding manner, liquid or gaseous fuel is pressed into the fuel pressure chamber 10 with the aid of a fuel pump. Due to the high ambient temperature, the evaporation of liquid fuels occurs regardless of their evaporation. k -

temperature, so that there is basically gaseous fuel at the outlet of the fuel pressure chamber 10 leading to the engine cylinder 3, which is extremely advantageous for mixture formation. Because of the high compression temperature of more than 1000 ° C., both ignitable and less ignitable fuels can be used, which also speaks for the multi-substance capability of the engine.

The combustion of the first stage takes place in the (small) engine cylinder 3, into which the fuel and the air meter via valves from the pressure chambers 8 and 10, i.e. only flow in when the cylinder pressure is lower than the pressure in the pressure chambers 8 and 10. Larger pressure peaks therefore do not occur, also because the working space is connected to the 15 l pressure chamber 8 during the main combustion, so that the pressure can equalize. This avoids a shock load dangerous for ceramics. Due to the two-stage compression and expansion, the temperature jumps in the cylinders are significantly smaller compared to those of the diesel engine, which also favors the use of ceramic as a material.

In the case of a cold engine, spark ignition takes place, in the case of a warm engine, the mixture ignites by itself. Since the expansion leads to a decrease in temperature, exceeding very high combustion temperatures can be avoided if the combustion is delayed by throttling the fuel supply , which is not associated with large efficiency losses due to the two-stage expansion. The machine can quasi stoichiometrically due to the high compression temperature ?

(Lambda close to 1.0) are operated, which prevents the formation of harmful NOx gases. The regulation of the inflow amount of air and a fuel into the engine cylinder 3 takes place by means of the valves 5 by changing the inlet cross-sections or the opening duration. With a steam engine, wi achieves extremely effective capacity control via the filling quantity.

After the inlet valves 5 have been closed and the expansion has ended, the combustion gas is pushed into the pressure chamber 9, the combustion gases being pushed out before the top dead center (0T) is reached by closing the valve 6, so that the residual gas remaining in the working area in turn is compressed to approximately the pressure prevailing in the pressure chambers 8 and 10. The pressure chamber 9 acts like an afterburning system, which makes the internal combustion engine environmentally friendly. The combustion gases enter the engine cylinder 4 from the pressure chamber 9, the inflow quantity also being regulated via a valve 5. After closing the inlet valve, the gas in the engine cylinder 4 expands (second stage expansion). The pushing outwards is also ended here before the 0T is reached. As a result, the remaining gas is compressed up to the pressure of the pressure vessel 9 in 0T.

Compression and expansion take place at low pressure values in the large cylinder and at high pressure values in the small cylinder. This results in relatively low maximum piston forces, so that the compression ratio can be increased considerably compared to the diesel engine, which leads to a high theoretical efficiency. The connection of a steel bottle (about 15 1 space is enough for a car) to the pressure vessel 8 enables energy storage. For this purpose, the valve control is set so that more gas mass is compressed and pressed into the pressure chamber 8 than, conversely, is removed from it for expansion. For example, if only one of the compressor cylinders is working, air is compressed and the vehicle is braked so that the pressure in the pressure chamber 8 rises. The braking energy is stored and is later partially available again. However, energy storage is also possible with full engine power. It provides additional energy, for example for acceleration purposes.

Exhaust gas energy recovery is also possible via steam generation, bypassing the exhaust gas turbocharger (ATL) which is unfavorable for the acceleration case. Water is pumped into the pressure chamber 8 through or around which the exhaust gas flows, so that there is always a small amount of water in it. The steam which forms is mixed with the gas for combustion before it enters the engine cylinder 3 in the pressure vessel 8. The steam expands in the engine cylinder 3 doing work. It can be warmed up prior to expansion by being led past hot engine components to be cooled. With this engine cooling there are no energy losses. The steam generation and admixture to the working gas enables more effective exhaust gas utilization than an ATL. The exhaust gas energy recovery via steam generation and admixing the steam to the working gas is of particular importance in ceramic engines, since the higher exhaust gas energy cannot be fully used by the ATL. In the drawing, a ceramic internal combustion engine is shown in an exemplary embodiment for power transmission, a swash plate drive. Swashplate drives have spatial advantages due to the axial cylinder arrangement, they allow full mass balancing and have small connecting rod deflection angles. The lack of impact loading means that the conrod bearings, which are common in conventional internal combustion engines, no longer occur. With the swash plate drive shown in FIG. 2, the generally existing difficulties of mounting such a drive can be overcome. A frustoconical swash plate 13 is by means of a motor block

10 14 attached cardan joint 15 held on the broad truncated cone end. In a flywheel 1 fixedly connected to the shaft 16, an inclined crank pin 18 directed to the cardan joint 15 is fastened. The inclined crank pin 18 is mounted in the centered bore 19 de swash plate 13 at the narrow truncated cone end. The mounting of the shaft 16 and the flywheel 17 takes place via roller bearings 20. When the shaft rotates, the swash plate 13 carries out a wobble movement. Dadurc the connecting rods 12 mounted in the swash plate 13 reciprocate the pistons 11 (see FIG. 1).

0 Overall, this results in an extraordinarily economical and elastic machine, which due to the two-stage expansion, without the aid of the electronics, always ensures almost complete combustion, so that pollutant emissions due to incomplete combustion are not to be expected and the use of a catalyst c is therefore unnecessary . A motor vehicle is less than the normal wheel brakes rather than braked by the compressor of the engine, the braking energy storage leading to a not insignificant fuel saving, especially in city traffic. Since the pressure chamber motor also contains the basic elements of the steam engine, which, as is well known in vehicles, does not require any gearbox, it is possible to reduce the gearbox to only two forward gears with only a slight increase in displacement. This can lead to significant cost savings. Since the brakes are hardly used anymore and the number of gear changes is reduced considerably by the only two gears left, the wear on the clutch, brakes and transmission is significantly reduced, with advantages in particular instead of the structurally complex and low-efficiency automatic transmission can be used. Starting the pressure chamber motor is very simple, because opening the valve to the pressure chamber is sufficient to set the motor in rotation when the motor shaft is in the starting position. The starter and battery are therefore no longer required for the starting process.

20th

25

Claims

1! Claims

1. Internal combustion engine for liquid and gaseous fuels, mi at least one combustion cylinder formed in an engine block into which the fuel and the combustion air are introduced under pressure, characterized in that the combustion cylinder (3) each has a pressure chamber (8, 10) for the combustion air and the fuel are switched on, which close the combustion cylinder (3) in whole or in part, so that the heat generated by the combustion by direct heat exchange with preheating and possibly - when using liquid fuel - evaporation of the fuel. the air is recovered.

2. Internal combustion engine according to claim 1, characterized in that the pressure chamber (10) for the fuel is in any case partially enclosed by the pressure chamber for the combustion air (8).

3. Internal combustion engine according to claim 1 or 2, characterized in that the pressure chamber (8) for the Brennennuπgsluft two compression cylinder (1, 2) are connected in series with an intermediate pressure chamber (7). &

4. Brennkraftmaschiπe according to one of claims 1 to 3, characterized ge indicates that the combustion cylinder (3) via a further Druckkam¬ mer (9) is a Machverbrennuπgsylinder (4) πachgeordπet.

5. Internal combustion engine according to one of claims 1 to 4, characterized ge indicates that to control the gas and air flows between the pressure chambers (7, 8, 9, 10) and working cylinder (1, 2, 3. 4) rotary valve, slide or mushroom valves (5, 6) are provided.

6. Internal combustion engine according to claim 5, characterized in that the exhaust valve (6) of the combustion cylinder (3) is controlled in dependence on the piston stroke so that the valve closes so early before reaching the top dead center position of the piston that when the top dead center the same pressure as in the pressure chambers (8, 10) for the combustion air. there is fuel.

7. Internal combustion engine according to one of claims 5 to 6, characterized in that the power control bezw. Energy storage takes place by changing the valve opening times or the passage cross sections in such a way that more gas mass is conveyed by compression into one - or more - pressure chamber (s) than it (it) releases for combustion and expansion.

8. Internal combustion engine according to one of claims 1 to 7, characterized ge indicates that the pressure chambers (7, 8, 9, 10) for the purpose of Abgasener¬ energy recovery are connected to a water reservoir from which loading if necessary, water is conveyed into one or more of the pressure chambers (7, 8, 9, 10), which after the evaporation is mixed with the gases flowing into the engine cylinder (3, 4).

9. Internal combustion engine according to one of claims 1 to 8, characterized ge indicates that the engine block with pressure channels or pressure lines for guiding cooling water, cooling or return air or fuel is provided, the steam formed at the or. the preheated gas is mixed with the gas flowing into the engine cylinder (3, 4).

»10. Internal combustion engine according to one of claims 1 to 9, characterized ge indicates that for power transmission -a swash plate drive with a substantially frustoconical, on its outer edge connecting rod (12) carrying swash plate (13) is provided, which by means of a porridge ¬ th end of the centrally fastened universal joint (15) is mounted on the engine block (14) and on the narrow side is provided with an inclined crank pin (18) held in a centered bore (19), which is mounted in a flywheel (16) fixedly connected to the shaft (16) 17) is attached.