DE1451643A1 - Graduated piston internal combustion engine - Google Patents

Description

Gesellschaft für Linde's Eismaschinen Aktiengesellschaft

(A-251) _U r _1fin A 63/07 7

^{l4b | b4J}

3.12,1965

Graduated piston combustion engine

The invention relates to a piston internal combustion engine, preferably working with compression ignition, the pistons of which with a step-like stepped extension is provided, which in locations near the outer dead center in a recess of the Cylinder cover is immersed, the lower wall part of the Recess is at least approximately cylindrical and surrounds the port set and the end face of the port set Lidfläohe of the recess is opposite, with the Position of the piston in the top dead center as far as technically possible. All air from the annular space around the port set of the piston into the Recess in the cylinder cover is displaced in front of the face of the port set

The aim of the invention is to enable that in such a Graduated piston internal combustion engine generates the fuel at low pressure and thus with, as far as the duration of the work process allows it, low speed in the process

ORlGlNAL INSPECTED

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Combustion air is introduced and still a very good combustion process and a good Duroh and burnout of the fuel is achieved

According to the invention, a free thermoset chamber remains between the port set and the wall of the recess, at least on one side thereof, and a fuel supply line opens in its area, in the at least approximately cylindrical wall of the recess, preferably without a nozzle. In this case, the fuel is introduced into the combustion air through this fuel supply line during part of the compression stroke at such a low speed or with low pressure that it gets into the air in the form of preferably large droplets. Furthermore, the cover surface adjacent to the passage space is designed in such a way that, together with the end face of the extension, it deflects the flow passing through the Durohrittsraum to a steady rotational flow and the free Durohrittsquersohnitt of the passage space and the radius of curvature of the cover surface of the recess and possibly the end face of the extension and the volumes of the subspaces are matched to one another in such a way that the rotational flow has a. high angular velocity is obtained, so that fuel droplets contained in it fall onto the deodorant surface of the recess, if necessary also ftuf the end face of the

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satzesfausentrifugiert, so that by means of the centrifugal egg a wall deposit of the fuel is achieved and in this way all the advantages of a combustion process aJEnit Wall deposits of the fuel can be exploited kfftmftn «These advantages consist primarily in the fact that the fuel by the large heat capacity of the relevant Wall at such a temperature until it evaporates is held that a chemical fall of the fuel molecules is prevented and that practically only fuel vapor is present in the area in which the combustion takes place

This type of wall accumulation by centrifuging is known to date in vortex chamber machines, in which at least a substantial part of the combustion air is displaced through an overflow duct into a vortex chamber and the corresponding rotational flow is generated there, through which the fuel is centrifuged out · With these vortex chamber ΐΊΐ »« must ιπ * 4τϊΐ1τΐ ** throughout the compression stroke and vice versa pressed by the Überströjakanal throughout the operating cycle of reaching each entering and "from djfcer vortex chamber gas content» contrast needs in atufemteolbenbrennkraftjnaÄOhine according to the present "findang **""during a Part of the piston stroke, which is determined by the ratio of the length of the piston extension to the total stroke and which corresponds to the insertion and removal

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fling the fuel and evaporate from the wall under a rotating flow conditions is designed, the air or the combustion gas through a

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relatively narrow cross-sections are pressed, while In addition, a large cross-section is available for the gas flow, In contrast to other multi-stage piston internal combustion engines, where the piston extension must be guided with very tight play in the recess in the cylinder cover, because in front of the end face of the piston extension and in front of the remaining ring surface of the piston are very different Pressures are to be achieved, is such a close game around the acted upon on its entire circumference by working gas Piston extension is not required in the stepped piston internal combustion engine according to the present invention, because it is anyway a flow of the compression air past at least a part the wall of the piston extension is provided · The stepped piston internal combustion engine thus enables the use of the wall attachment without using a high pressure spraying device for the fuel and without throttling the working gas in an overflow channel.

In an advantageous embodiment of the stepped piston internal combustion engine According to the invention, the fuel is supplied in a measured amount at predetermined times introduced into the combustion air by a pump

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A stepped piston internal combustion engine according to the invention can also be designed in an advantageous manner as an internal combustion engine without an injection pump and nevertheless also work as a compression-ignition engine according to the diesel process if appropriately dimensioned. For this purpose, the internal combustion engine is then configured such that the opening into the wall of the recess fuel supply line opens into a pre-storage chamber which is connected to a main fuel tank and one which opens an additional channel, on the other hand in the surrounding recess annular face of the zylinderdeokels opens. As air flows over from the annular space around the piston extension through the free passage cross-section into the space in front of the end face of the piston extension, a pressure gradient forms between the two openings of the channels on the one hand in the annular surface of the cylinder cover - where practically the total pressure of the combustion air prevails in front of the opening , which is displaced from the annulus - and the mouth in the approximately cylindrical wall of the recess - where a large part of the total pressure of the combustion air is converted into flow energy and thus the effective static pressure in front of the mouth is reduced by a corresponding amount. This high pressure gradient is used to displace the fuel from the pre-storage chamber into the combustion air in the free passage cross-section. A similar arrangement of two of a front

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storage chamber outgoing channels »? is known in machines without injection pumps with a swirl chamber.However, these have the disadvantage that the pressure gradient practically takes hold during the entire compression stroke, even towards the end of the compression stroke as a result of the decreasing piston speed and the increasing equalization of the pressure in front of the piston on the one hand and in the vortex chamber on the other hand, it gets smaller. With these vortex chambers, the point in time at which the fuel is introduced into the combustion air can only be influenced with the help of special additional devices and can only be determined with great difficulty.But for all things, it is difficult to achieve that the fuel is only introduced towards the end of the compression stroke and while the fuel is carried along by the combustion air still in good manner and spun out "· an au early Einteingenfcron fuel due but etoen to early onset of combustion and thus a rise in pressure already% or the piston reaches top dead center has been reached and thus a loss of exploitable Energy ,, These disadvantages are avoided in the stepped piston internal combustion engine according to the invention, since the mentioned pressure gradient used to deliver the fuel only occurs towards the end of the compression stroke, namely only when the piston extension into the recess in the cylinder end ckel enters · As already mentioned, through appropriate voting

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the length of this piston extension to the size of the piston stroke defines the point in time at which the desired flow conditions occur on part of the piston stroke, while on the other part of the piston stroke there is no throttling of the gas flow. This will make the fuel too only then introduced into the combustion air when it is already largely compressed, so that a perfect Entrainment of the fuel is achieved. The fuel « Supply line can be in the area of the confluence with the Wall of the recess are approximately perpendicular to this, but it can also form an acute angle with this wall, in particular in the shape of a circular arc from the pre-storage chamber be curved in such a way that the confluence points towards the main combustion chamber or towards the main piston head, so that an intense Entrainment of the fuel at the mouth is achieved and on the other hand it is avoided that in the first part of the combustion process Combustion gases, which flow through the free cross-section of the durometer, into the mouth of the fuel supply line blow in

Both in the case of the internal combustion engine that operates with a pump and of the internal combustion engine without an injection pump made sure that the introduction of the fuel takes place at a point in time when the port set is so deep into the recess has penetrated that the distance between

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mouth of the! fuel supply line and end of the free Passage space on the end face of the extension is so large that this through the piston position at the time of Retraction of the Kraftäoffes given route at least under Taking into account the time * it takes for the droplets to reach the edge from the mouth of the fuel supply line to reach the end face of the extension, to accelerate the emerging from the mouth of the fuel supply line Fuel droplets to approximately the speed of the air flow is sufficient.The otherwise approximately cylindrical see wall of the piston process and / or the in upper Dead center position of the piston corresponding to this opposite The wall of the recess of the cylinder cover can be profiled in the area of the free Durohetresraumes such that at the time the pushing of the fuel into the combustion air causes a particularly high overflow speed at the The opening of the fuel supply line prevails · For this purpose, in particular the wall of the piston extension can be in this way be designed that a particularly narrow point of the free passage cross-section at the time of the flow over the Fuel is formed in front of the confluence of the fuel supply line in the wall of the recess · So while to achieve this purpose, the wall of the piston extension is preferably designed to deviate from the cylindrical shape can be, one or both can be practically equally

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of said walls be profiled in such a way that the passage through the free Durohrittsquersohnitt to the space in front of the end face The air flowing through the piston extension is forced into a swirl flow, which is a helical flow in the combustion chamber in the recess in front of the end face of the piston extension, so that the absolute angular velocity amount the current becomes even bigger.

In the drawing, two exemplary embodiments of the subject matter of the invention are shown
Figure 1 shows a stepped piston machine with an external pressure less

Fuel inlet from a pre-storage chamber and Figure 2 shows a stepped piston internal combustion engine with low-pressure injection

characters
In both cases, 1 denotes the cylinder bore in which a piston 2 can be displaced. The piston 2 is provided with a piston extension 3 which dips into a recess 4 in the cylinder cover 5 Curved way

In the internal combustion engine shown in Figure 1, the fuel is through a feed line 7 from one in the Zeiohnung not shown main memory of the pre-storage cameras 8 supplied, on the one hand through a channel 9 with

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is connected to the annular surface in the cylinder cover 6 around the recess 4 and, on the other hand, adjoins a channel Io which opens into the side wall of the recess 4 «

As soon as the piston extension 2> During the upward stroke of the piston 2 -into the recess 4, air is drawn in from the annular space 11 the wall of the extension 5 over into the space 12 in the recess pressed, where there is a vortex flow, such- ^ that the entrained fuel to the cover surface 6 is centrifuged out *

In the device shown in Figure 2 , instead of the channels J _S 9 and 1o with the pre-storage chamber 8, a power t off-

to feed channel 13 is provided, through which a predetermined Time a predetermined amount of fuel by means of a pump not shown in the drawing under low Druok in the combustion air is introduced «

Claims

009813/0737

Claims (1)

Claims 1Λ Piston internal combustion engine preferably working with self-ignition, the piston of which is provided with a stepped set of ports which, depending on the position of the piston in the vicinity of the outer dead center of the Eolben dips into a recess in the cylinder cover, the lower Wall part of the recess is at least approximately cylindrical and the port set at the outer dead center position of the piston surrounds and where the face of the port set has a Cover surface of the recess is opposite and furthermore so far with the position of the piston in the outer dead center technically possible all air from the annulus around the port set of the piston into the recess of the cylinder cover the end face of the port set is displaced, characterized in that that a free passage space is formed between the port set and the wall of the recess at least on one side is and in its area in the at least approximately cylindrical wall of the recess at least one fuel supply line opens through which the fuel during part of the compression stroke at such a low speed is introduced into the combustion air that he is in In the form of preferably large droplets, the cover surface of the recess also adjoins this 008813/0737 is designed on the free passage space such that it, together with the end face of the port set, through the flow passing through the free passage deflects to a steady rotational flow and the free passage transverse step of the passage space and the curvature egg
radius of the top surface of the recess and, if necessary, the end surface of the piston extension and the volumes of the subspaces are matched to one another in such a way that the rotational flow receives such a large angular velocity that fuel droplets contained in it are centrifuged out onto the top surface of the recess and possibly the end surface of the port set. 2 piston internal combustion engine according to claim 1, characterized in that that the introduction of fuel to tinem Time takes place at which the extension has penetrated so deep into the recess that the distance between Confluence of the fuel supply line and the end of the free passage space at the end face of the port set. is so large that this distance to accelerate the fuel droplets emerging from the confluence in the Air flow at approximately the same speed as this air flow is sufficient. J5. Piston internal combustion engine according to claim 1, characterized in that that the fuel at predetermined times in 909813/0737 (A 251) U51643 the measured amount is pushed into the combustion air by a pump, 4 piston internal combustion engine according to claim 1, characterized in that that the fuel supply line opening into the wall of the recess is in a pre-storage chamber opens, which is connected to a main fuel tank and into which another channel opens, which on the other hand opens into the annular surface of the cylinder cover surrounding the recess 5 · Procedure for operating a, preferably with compression ignition working piston combustion engine, the piston of which is provided with a stepped extension that when the piston is in the vicinity of the outer dead center it thaws into a recess in the cylinder cover, the lower wall part of the recess is at least approximately cylindrical and surrounds the piston extension and the end face of the port set opposite a cover surface of the recess and furthermore with the position of the piston in the outer Dead center as far as technically possible all air from the annular space around the port set of the piston into the recess in the cylinder cover is displaced in front of the face of the port set, characterized in that the each for one work cycle required fuel under low pressure or with 9098T3 / 0737 ^(A251) M H5164.3 low speed in the form of large drops into the space from the annular space around the piston extension the end face of which air flowing towards the end of the compression stroke is introduced and then the air containing the droplets Air in the space in front of the end face of the piston extension is forced into a rotational flow so high angular velocity that the premix formed from fuel droplets and air by centrifuging the fuel droplets on the wall of the said room again is separated and the fuel deposited in this way on said wall then, supported by the above stroking hot air, is evaporated and thereby that too burning working mixture is formed * 9098 j 3/073 7