KR20130101088A - Internal combustion engine, exhaust valve and cylinder head therefor, and production, operation and use of an internal combustion engine - Google Patents

Abstract

The present invention relates to an internal combustion engine, in particular a large two-stroke diesel engine, comprising an cylinder (1) and at least one combustion chamber (2) limited by a piston (3) interacting with the crankshaft, the combustion chamber being an exhaust valve ( 9; 109; 309, one or more combustion gas exhaust ports 20; 120; 320; 420 and one or more charge air intakes 4 respectively formed between the valve disks 8; 108; 308 and the disk seats assigned thereto. And the exhaust valve 9; 109; 309 can be operated between the open position and the closed position. The combustion gas exhaust ports 20; 120; 320; 420 are connected to one or more exhaust channel 11 and also to one or more combustion gas exhaust channels 18; 118a, 118b; 318, 318a; 418, 418a. For example, a portion of the combustion gas generated during combustion can be recycled to the charge air intake 4. The invention also relates to such exhaust valves for internal combustion engines (9; 109; 309) and cylinder heads. The present invention provides a throttle device (10; 110; 310) for discharging combustion gas in a fixed manner, fixed to the exhaust valve (9; 109; 309) or integrally molded as part of the exhaust valve (9; 109; 309). It features. The invention also relates to a method for producing an internal combustion engine, to a method for operating an internal combustion engine and to use for an internal combustion engine.

Description

Manufacture, operation and use of internal combustion engines, exhaust valves and cylinder heads and internal combustion engines for such engines, and the like. {INTERNAL COMBUSTION ENGINE, EXHAUST VALVE AND CYLINDER HEAD THEREFOR, AND PRODUCTION, OPERATION AND USE OF AN INTERNAL COMBUSTION ENGINE}

The invention relates to an internal combustion engine comprising the features of the preamble of claim 1, in particular a large two-stroke diesel engine, to an exhaust valve and cylinder head for such an internal combustion engine according to the preamble of claim 13, to the preamble of claim 20. A method of manufacturing such an internal combustion engine according to the present invention, the use of such an internal combustion engine according to the preamble of claim 26 and a method of operating such an internal combustion engine according to the preamble of claim 27.

Combustion gas recirculation is known in the case of internal combustion engines of this type to provide recycled combustion gas to the charge air supplied to the combustion chamber (s) of the internal combustion engine. In this way, the emission of nitrogen oxides (NO _x ) is reduced. The supercharged air is therefore pre-compressed and optionally pretreated, for example in addition to dried, filtered or temperature controlled external pure scavenging air, other scavenging gas components, for example scavenging. And a component of the mixer consisting of the recycled combustion gas. In such a case the charge air may contain other components in addition to the scavenging gas and / or pure scavenging, for example evaporated natural gas.

In order to feed the combustion gas into the combustion chamber, in this case, for example, the combustion gas recycled to the scavenge is mixed and the combustion chamber is scavenged into the mixer by one or a plurality of cavity inlets, for example an inlet slot. It is known. It is also known that the recycled combustion gas of the combustion chamber on the one hand and the charge air residual on the other hand are introduced into the combustion chamber via separate inlets, so that a mixer forming the charge air is only formed in the combustion chamber. In this case the invention can be combined with all conventional methods of recycling the combustion gas into the combustion chamber.

For this purpose in an internal combustion engine of this type known from German patent application DE 10 2005 057 207 A1, a second exhaust valve is provided in addition to an exhaust valve for connecting or disconnecting the exhaust channel to the combustion chamber. The combustion chamber is connected to or separated from the recycle line. This structure is relatively expensive.

In addition, in the case of the internal combustion engine shown in European patent application EP 2 151 569 A1, the recirculation line branches in the exhaust channel disposed downstream of the exhaust valve from the flow point of view, and this recirculation line is provided to the valve stem of the exhaust valve. It can be opened and closed by a second valve device and a valve holder in the exhaust channel assigned to it. A sleeve with circumferential slots is provided, for example for this purpose, provided in the valve stem of the exhaust channel. The valve holder fixedly disposed in the exhaust channel also has a sleeve with slots, which covers the branch for the recirculation line. Since the exhaust valve and the valve stem are rotated repeatedly by the rotating mechanism, branches can be opened and closed into the recirculation line to reduce non-uniform operation of the valve seat. Although it is not necessary here for a second separate valve to open and close the recirculation line, it is difficult to clock the open cycle and the open phase determined by the rotating mechanism during the engine cycle to a stage suitable for the engine operating cycle and the recirculation stage. see.

In addition, in the case of a four-stroke engine known from Japanese Laid-Open Patent Publication JP 6 241 127, a recirculation line branches in an exhaust channel disposed downstream of the exhaust valve, and this recirculation line is opened and closed by a separate valve. At the same time it is formed as a throttle flap for the exhaust channel and as a result throttles the flow rate through the exhaust channel upon opening of the recirculation line. In this case the recirculation valve-exhaust channel throttle flap is in a position to throttle the exhaust channel and open the recirculation line during the entire sweep.

Finally, in the case of internal combustion engines known from DE 10 2008 058 612 A1, the recirculation line diverges from the exhaust channel arranged downstream of the exhaust valve in terms of flow, where the exhaust channel is also opened and closed by a separate valve. In an embodiment a throttle device is provided in an area disposed downstream of the valve connected upstream of the recirculation line in the exhaust channel, the throttle device having a displaceable flap. The impact pressure for opening the flap occurs at the opening of the main exhaust valve and is closed by the preload spring when the pressure is sufficiently low. This solution is also expensive in relation to the clocking of the exhaust valve, the throttle device and the valve disposed upstream of the recirculation line and overall structurally expensive, as well as the adjustment of the pretensioning force of the spring closing the throttle device.

An object of the present invention, which starts at this point, is to provide an internal combustion engine, an exhaust valve and cylinder head therefor, and the like, to exhaust the combustion gas mixed with fresh air as little as possible for recycling or for other purposes. To provide a method of operating an internal combustion engine. Also provided are innovative uses and manufacturing methods for the found internal combustion engines.

The task relates to an internal combustion engine comprising the features of claim 1, to an exhaust valve comprising the features of claim 13, to a cylinder head comprising the features of claim 19, to a manufacture comprising the features of claim 20. With regard to the method, it is solved in connection with the use comprising the features of claim 26 and with respect to the method of operation of an internal combustion engine comprising the features of claim 27.

For this purpose there is provided according to the invention a throttle device which is fixed to the exhaust valve or which is integrally formed with the exhaust valve, the throttle device having a combustion gas from the closed position of the exhaust valve to the desired opening degree of the exhaust valve. In the exhaust opening region, the inlet of the combustion gas into the exhaust channel is suppressed or throttled at least more strongly than in the exhaust gas exhaust opening region of the exhaust valve to an open position of an opening greater than the desired opening, and this exhaust gas exhaust opening region The throttle device therein preferably throats no inflow of combustion gas into the exhaust channel or at least less strongly than in the combustion gas exhaust opening region of the exhaust valve. A branch of the combustion gas exhaust channel, located on the throttle device and the exhaust port or near the combustion chamber exhaust port controlled by the exhaust valve, preferably allows the throttle device to allow inlet of combustion gas into the combustion gas discharge channel in the combustion gas discharge opening region. Is arranged such that it does not throttle at all or at least not significantly throttle.

In the flue gas outlet opening region the exhaust valve opens a relatively narrow annular gap and uses its throttle device to block the outflow line leading outwards or at least to narrow down the diameter or flow path cross section of the outlet line. In contrast, the combustion gas discharge channel is open. Thus, at the very beginning of the opening process of the exhaust valve, the combustion gas pressure in the combustion chamber, which is still very high, is first converted into a flow coming out through the annular gap of the exhaust valve at high speed and at high dynamic pressure. This flow is then converted to dynamic pressure through a throttle device that closes the exhaust channel again or at least reduces or crosses the flow path cross section so that the high pressure combustion gases are not blocked by the throttle device at the same time or at least only slightly disturbed. It flows into the combustion gas discharge channel.

At the same time, pure or at least combustion-free combustion gas in the combustion chamber is located within the time of the initial combustion gas discharge opening area of the exhaust valve (when the exhaust valve is opened), but a mixer consisting of combustion gas and charge air is not located, for example This may for example be in time of the exhaust gas outlet opening region of the exhaust valve. In this case, in particular, the initial opening period of the exhaust valve is important and this step is not important at the end of the closing process, since the pressure of the combustion gas is generally high enough only during the downward piston stroke, so that the combustion of the discharged combustion gas is recycled. The gas may be recycled towards the charge air inlet towards the combustion chamber inlet which does not connect the pump in the middle.

Therefore, depending solely on the clocking of the exhaust valve, only completely or at least relatively pure combustion gas reaches the combustion gas discharge channel, and the combustion gas discharge channel becomes a recirculation line if it discharges combustion gas for combustion gas recirculation into the combustion chamber. Can be. In contrast (if the opening of the exhaust valve is greater) all or into the exhaust channel where the combustion gas-charging air-mixer present during the time of the exhaust gas exhaust opening area of the exhaust valve is not throttled or at least only weakly throttled. At least mostly discharged and not at all or only a small amount is reached into the flue gas discharge channel or in the case of flue gas recirculation.

Technically easy, in connection with the clocking of combustion gas emissions and with the easy construction of existing engines and engine concepts, which is always synchronous to the exhaust valve for recycling the combustion gas towards the inlet of the combustion chamber or for other purposes. And in particular in connection with easy adaptation is that the throttle device is formed integrally with the exhaust valve or at least installed or fixed to the exhaust valve. The desired opening of the exhaust valve to the combustion gas exhaust opening region can also be affected through the formation of an exhaust valve or a throttle device molded to or fixed thereto but not tied to the pressure surge that appears upon opening of the exhaust valve.

If anyone has an exhaust valve formed in accordance with the invention, the exhaust valve is sufficient to replace the exhaust valve (s) in many cases even in existing engines, so that combustion gases can be discharged in accordance with the invention. This is particularly effective in throttle devices where only the throttle exhaust channel is not to be throttled and completely closed. In contrast, if the throttle device must completely close the exhaust channel, it may be necessary to rework the corresponding contact surfaces of the exhaust channel, which must be well aligned with the valve stem. In this case or in the absence of a flue gas discharge channel in the cylinder head installed in the engine, the exchange of an existing entire cylinder head through the cylinder head formed according to the invention can be advantageous. The production method according to the invention is particularly advantageous in these cases, ie where existing internal combustion engines have to be adapted for combustion gas emissions or combustion gas recycling.

In addition, a method is provided for the discharge of combustion gases in an internal combustion engine operating in accordance with the invention, in particular in large two-stroke diesel engines, and in particular for the purpose of recycling the combustion gases, where the internal combustion engine interacts with the cylinder and the crankshaft. And one or more combustion chambers limited through the piston, wherein the combustion chamber has at least one combustion gas exhaust port and at least one supercharged air intake formed between the valve disk of the exhaust valve and the disk seat assigned thereto. In this case, since the combustion gas exhaust port is connected to one or more exhaust channel and one or more combustion gas exhaust channel, a part of the combustion gas generated during combustion, for example, can be recycled to the boost air intake port. In this case the exhaust valve is operated between an open position and a closed position, by means of a throttle device in which the inlet of the combustion gas into the exhaust channel in the combustion gas discharge opening region of the exhaust valve is fixed to the exhaust valve or integrally molded with the exhaust valve. It is suppressed or throttled at least more strongly than in the exhaust gas exhaust opening region of the exhaust valve, from the larger opening to the open position. In contrast, the inlet of the combustion gas into the combustion gas discharge channel in the combustion gas discharge opening region is preferably not throttled or at least significantly throttled through the throttle device.

In this case the throttle device fixed to the exhaust valve or integrally molded with the exhaust valve has advantages in particular in a two-stroke engine comprising combustion gas recirculation. Therefore, in order to avoid loss of work, the exhaust valve can be opened later than in current two-stroke engines containing combustion gas recirculation and the exhaust valve is usually relatively wider (or separate) prior to passage of the intake slot. Since the recirculation exhaust valve of must be opened, the mixing of the recirculated combustion gas and the freshly introduced boost air can be suppressed. In order to enable the inlet of combustion gas into the combustion gas discharge channel, according to the invention, downstroke to a piston position with a maximum of 40 ° crankshaft angle above the same piston position where the opening of the intake port (s) (intake slots) is used. It is not necessary to open the exhaust valve before reaching for a while. In some cases a later opening of the exhaust valve may be advantageous, but anyway may be advantageous before the desired use of the combustion chamber by the inlet (s) (intake slots). The high pressure of the recycle gas is also particularly important in this case, since the supercharging pressure must be relatively high. If the recirculation pressure is high enough, the pump can be removed.

In particular, in the case of an exhaust valve in which the check valve provided in the combustion gas discharge channel is located in the exhaust gas discharge opening region, the inflow of the combustion gas-charging air-mixer coming into the unthrottled exhaust channel is suppressed, so that the combustion gas discharge side In the main, the check valve is closed for the combustion gas-charging air-mixer which is supplied with a higher pressure. In this case, since the check valve in the combustion gas discharge channel may be an actively controlled check valve, especially in the case of an exhaust valve operated by a camshaft, the amount of combustion gas discharged can be better controlled. In the case of the exhaust valve which is controlled electronically and not by the camshaft but rather by the drive itself, the control time of the exhaust valve can be adjusted accordingly, so that the amount of combustion gas discharged can be controlled.

As an alternative or in addition to the measures described above, during the time of the exhaust gas outlet opening region, the throttle device suppresses or minimally throttles the inlet of the combustion gas into the combustion gas exhaust channel in the exhaust gas exhaust opening region of the exhaust valve. The throttle device may be formed or a branch of the throttle device and the recirculation line may be arranged on the exhaust side so that the same effect of inhibiting the existing combustion gas-charging air-mixer from entering the combustion gas discharge channel is achieved.

In an advantageous development of the invention the throttle device has a radial throttle projection, which projects radially from the valve stem of the exhaust valve, preferably the throttle projection is provided in the region of the valve stem, the throttle projection being When the exhaust valve is open in the combustion gas discharge opening region, it is located in the region of the exhaust channel, which is disposed downstream of the exhaust side branch of the combustion gas exhaust channel in terms of flow. While the exhaust valve is located in the combustion gas discharge opening region, the perfusion of the exhaust channel is throttled and pumped or bypassed into the combustion gas discharge channel due to the dynamic pressure occurring at the throttle protrusion.

In particular, if in this case the throttle projection is at least loosely in contact with the inner circumference of the exhaust channel in the region of the exhaust channel, formed as an outlet cylinder, depending on the type of piston moving, the combustion gas is opened by the exhaust valve in the combustion gas discharge opening region. If so, the flue gas discharge channel is reached without significant volume loss or pressure loss. Additional pumps in the recirculation line which are recycled towards the inlet port, which are used as combustion gas discharge channels in the case of combustion gases which are discharged for recycle purposes, can be removed. If the outlet cylinder is cylindrical in the region where the throttle projection is located in the case of an exhaust valve located in the combustion gas exhaust opening region, which is disposed downstream of the exhaust side branch of the combustion gas exhaust channel from a flow point of view, this type of large The valve rotation mechanism, which is usually provided in two-stroke diesel engines, often prevents intermittent rotational movement of the valve with the stem circumferential propeller design, can be maintained in a conventional manner.

In the above-mentioned advantageous development of the invention, the flue gas discharge channel may be spaced from the flue gas outlet and branched out of the exhaust channel. In this case, the throttle protrusion can be provided in the region of the valve stem, and the throttle protrusion is located in the exhaust channel at approximately the branch height of the combustion gas exhaust channel when the exhaust valve is open in the exhaust gas exhaust opening region. In such a case the exhaust channel may have a diameter extension which is especially circular in the region of the branch of the combustion gas exhaust channel, so that the combustion gas entering into the exhaust channel is a branch of the combustion gas exhaust channel when the exhaust valve is open in the exhaust gas exhaust opening region. The throttle protrusion can be turned at a position at the height of. The diameter extension in this case preferably has a size such that the inflow of combustion gas into the exhaust channel is preferably not throttled at all, while the diameter extension is such that the exhaust valve is open in the combustion gas discharge opening region or the throttle projection Has a magnitude such that the inflow of the combustion gas is throttled less strongly than if it is located in an area disposed downstream of the branch of the combustion gas discharge channel in terms of flow.

On the other hand it is conceivable that the throttle protrusion is placed in the region of the valve stem, located near the valve disc, and the throttle protrusion is located in the combustion chamber when the exhaust valve is open in the exhaust gas discharge opening region. It is therefore possible to enter into the exhaust channel through an annular channel formed between the throttle projection and the disc seat. In this case the branch of the recirculation line is preferably arranged in the region of the exhaust channel, directly adjacent to the valve seat or directly to the valve seat. In such a case, the stroke of the exhaust valve does not need to be very large, so that at the same time in the case of the throttle protrusion located in the combustion chamber, a sufficiently large opening of the exhaust valve can be ensured for the discharge of the combustion gas-air-mixer and the exhaust valve discharges the combustion gas. The throttle projection can slide in the region of the exhaust channel disposed downstream of the branch of the combustion gas exhaust channel from the flow point of view when open in the opening region.

Needless to say, the throttle projection turns at least when the exhaust valve is open in the exhaust gas discharge opening area and divert the flow into the combustion gas discharge channel when the exhaust valve is open in the combustion gas discharge opening area. The exhaust valve therefore advantageously does not have edges that are unfavorable to the flow conditions, but rather-at least on the front side, i.e. on the side of the throttle projection opposite the branch of the recirculation line-in the combustion gas discharge opening region. The combustion gas flowing into the region of the exhaust channel in front of the throttle projection can be diverted from the region of the exhaust channel into the combustion gas exhaust channel which is laterally diverged from the combustion gas outlet opening region.

According to another advantageous development of the invention, the exhaust channel has an outlet cylinder disposed downstream of the combustion gas exhaust from a flow point of view, wherein at least one exhaust line and at least one combustion gas exhaust channel branch off the outer circumference of the outlet cylinder. The branch of the exhaust line is in this case provided downstream of the branch of the combustion gas exhaust channel. In addition, in this case, the throttle device may have a slide which is slidably received in the outlet cylinder, which is mainly axially slidable, the slide circumventing at least a branch of the exhaust channel when the exhaust valve is open in the combustion gas discharge opening region. It is shaped and connected to the exhaust valve to cover it locally and cover the branch of the combustion gas exhaust channel when the exhaust valve is open within the exhaust gas exhaust opening region.

In this case it is advantageous on the one hand not only to enter into the exhaust channel if the exhaust valve is located in the combustion gas exhaust opening region but also to enter the combustion gas into the combustion gas exhaust channel if the exhaust valve is open in the exhaust gas exhaust opening region. Backflow into the outlet cylinder of the inlet of the air-mixer or withdrawal of combustion gas therefrom is also inhibited or at least impeded.

As already mentioned above, in this case the slide does not need to operate absolutely completely airtight on the inner circumference of the outlet cylinder. As long as the advantageous operation of the slide is fulfilled as a throttle in the exhaust channel when the exhaust valve is in the flue gas outlet opening region and as a throttle in the branch of the flue gas exhaust channel when the exhaust valve is open in the exhaust gas outlet opening region, It is not a problem if some gas leaks between the outlet cylinder walls.

In this case it is generally advantageous with regard to the already mentioned functionality of the provided valve rotating mechanism, when the slide is formed as a cylindrical sliding sleeve and the outlet cylinder is also cylindrical. It should be noted, however, that for exhaust valves without such valve rotation mechanisms, completely different geometry can be considered.

In this case a slide or sliding sleeve can be connected to the valve stem of the exhaust valve, for example by a radial strut. However, it would also be conceivable to implement a sliding sleeve as a tube starting from the side of the combustion chamber in the valve disk, which has a through hole for flow in the region near the valve disk.

In this case, one exhaust channel may be provided which preferably comprises a plurality of exhaust channel branches branching from the outlet cylinder or a plurality of branches distributed at the circumference of the outlet cylinder, so that the exhaust valve is opened in the exhaust gas discharge opening region. If present, the inlet of the combustion gas-charging air-mixer can be facilitated. As an alternative or in addition to this, the exhaust channel can extend in a ring shape around the outlet cylinder and open in a ring shape towards the outlet cylinder or have a branch opening in a ring shape towards the outlet cylinder.

The throttle by a slide or sliding sleeve, such as in development, includes a throttle protrusion which is located in the exhaust channel when the exhaust valve is open within the exhaust gas exhaust opening area and is provided with a diameter extension therein so that it is possible to turn the throttle protrusion. In an advantageous development involving an exhaust channel / combustion gas discharge line that can be ringed or closed, a throttle device, ie a throttle protrusion or slide or sliding sleeve, can be arranged relatively far from the combustion chamber in the exhaust channel. In such a case the throttle device is not exposed to high heat loads and can be formed relatively economically if the throttle protrusion is for example hollow. Since the branch of the flue gas discharge channel is also relatively spaced away from the combustion chamber in this case, there is no thin material web subjected to high thermal loads between the branch of the flue gas discharge channel and the combustion chamber inner wall.

In this case, on the other hand, a constant size must be provided for the outlet cylinder, in which the branch of the combustion gas discharge channel and the sliding area of the throttle device are accommodated. Therefore, development may be advantageous that includes a throttle projection located in the exhaust gas exhaust region in the combustion chamber and a combustion gas exhaust channel branching near the combustion chamber exhaust or disk seat. In addition, direct and lossless introduction of the combustion gas into the combustion gas discharge channel is thus also achieved.

Further advantageous third developments of the invention have been tailored in this direction, and the exhaust channel likewise has a cylindrical outlet cylinder, preferably downstream of the combustion gas exhaust port, in terms of flow, but this comprises such an outlet cylinder. It may be much shorter than in the aforementioned development. Since the outlet cylinder in this case receives an end projecting in the axial direction of the valve stem in the form of a cross section of the outlet cylinder on the side which orients the combustion chamber in the valve disc, if the exhaust valve is closed or opened in the combustion gas discharge opening region, The outlet channel is closed or at least the inlet is throttled into the outlet channel. In this case the combustion gas discharge channel branches in the radially diverging region (i.e. in the region of the disk seat of the valve disc) outside of the stage, which is covered by the side which orients the combustion chamber in the valve disc upon closure of the exhaust valve. have. Therefore, the combustion gas discharge channel is separated from the combustion chamber if the exhaust valve is closed.

Advantageously, however, the branching zone is located radially outwardly adjacent to the stage or at least near the periphery of the stage, so that the disc seat where the side of the valve disc orients the combustion chamber when the exhaust valve is closed diverges. It extends radially outwards farther than the area, as a result of which a reliable closure of the combustion gas exhaust port is ensured upon closure of the exhaust valve.

The advantage in this embodiment is that the structural cost is particularly small for the throttle device. If only the rear side of the valve disc extends slightly through the stage, and provided contact with the outer circumference of the outlet cylinder, the inner circumferential surface of the outlet cylinder can be properly precision machined and well aligned with the valve stem axis. The branch of the flue gas discharge channel opens directly to the combustion chamber, and the head structure or parallel structure of the inlet or branch of the recirculation line with respect to the branch or inlet of the exhaust channel is also advantageous with regard to the optimization of combustion gas inlet into the flue gas discharge channel. Proved. On the other hand, in the region of the branch of the combustion gas exhaust channel, high heat loads in this case occur, in particular, in the thin material web of the combustion chamber wall between the combustion chamber and the combustion gas exhaust channel. In this case, therefore, a coolant line provided in the material of the combustion chamber wall in the region of the combustion gas exhaust port, in particular in the material between the disc seat and the combustion gas exhaust channel, is advantageous.

In this case, if the combustion gas discharge channel extends in a ring shape towards the combustion chamber or branches from the combustion gas exhaust port by a branch which is open in a ring shape toward the outlet cylinder, the coolant line preferably circulates at least locally. In this case a branch opening in a ring shape is advantageous for the recovery of the combustion gas carried into the combustion gas discharge channel, which branch can preferably be opened into the material of the combustion chamber wall like beads.

Advantageous embodiments of the present invention are described in detail below with reference to the accompanying drawings.

1 is a schematic diagram of an internal combustion engine according to a first embodiment of the present invention.
2 is a partial cross-sectional view of the combustion chamber exhaust port of the internal combustion engine shown in FIG. 1 when the exhaust valve is closed.
3 is a view corresponding to FIG. 2 when the exhaust valve is opened in the combustion gas discharge opening region.
4 is a schematic diagram of a region of a combustion chamber exhaust port according to another embodiment of the present invention when the exhaust valve is opened in the combustion gas discharge opening region.
FIG. 5 is a view corresponding to FIG. 4 when the exhaust valve is opened in the exhaust gas discharge opening region. FIG.
6 is a schematic view of the area of the combustion chamber exhaust vent according to another embodiment of the invention when the exhaust valve is closed.
FIG. 7 is a view corresponding to FIG. 6 when the exhaust valve is opened in the combustion gas discharge opening region. FIG.
8 is a view corresponding to FIGS. 6 and 7 when the exhaust valve is opened in the exhaust gas discharge opening region.
FIG. 9 is a schematic diagram of a combustion chamber exhaust port region that is slightly modified compared to the embodiment shown in FIGS. 6 to 8.
10 is a diagram of pressure curves drawn according to the crank angle.
11 is a diagram of flow path cross sections drawn along crank angle.

The main field of application of the present invention is large two-stroke diesel engines, for example, where their use can be found in marine propulsion systems. The basic structure and function of such devices are known in nature. In this case, part of the exhaust gas often has to be returned, ie recycled, into the working chamber 2 for the reduction of NO _x emissions. In order to ensure ease of control and to ensure accurate measurement, the so-called recycle gas should be as pure as possible a combustion gas, ie exhaust gas which is not lean by the scavenging gas.

An internal combustion engine comprising combustion gas recirculation, which can be seen by way of example in FIG. 1, has been developed in accordance with an embodiment of the present invention. However, the present invention is not limited to the structure of the recycling apparatus shown purely by way of example in FIG. Other exhaust valves and cylinder heads implemented in accordance with the present invention may be used, as can be seen in the other examples of FIGS. 2 to 9.

In addition, the present invention is not limited to internal combustion engines comprising combustion gas recirculation but may also be used to vent combustion gases for other purposes. Therefore, when referring to the "recirculation opening area" of the exhaust valve in the following, this actually means a "combustion gas discharge opening area" for internal combustion engines comprising combustion gas recirculation and the "recirculation line" is replaced by a general "combustion gas discharge channel". do. However, the above-described embodiments of the present invention can also be used when the combustion gas must be discharged or withdrawn for combustion gas recirculation and other purposes.

A cylinder 1 of an internal combustion engine, which may have a plurality of cylinders arranged in a line, is shown in FIG. 1. The combustion chamber 2 included in each cylinder 1 is not shown in detail but is constrained downwards by an up and down movable piston 3 which interacts with the crankshaft by means of a piston rod, a cross head and a connecting rod. The air inlet slot 4 of each cylinder 1 is via a supply channel 5 assigned to it, which is connected to a distribution tube 6 capable of supplying the supercharged air to all the respective cylinders. . Therefore, the inlet slot 4 operates as an air inlet which can supply combustion air to the combustion chamber 2.

The combustion gas exhaust port 20 can be opened and closed by an exhaust valve 9 provided in the region of the cylinder cover which restricts the combustion chamber 2 from above. In addition, although not shown in detail, a fuel injection device may be provided.

The combustion gas exhaust port 20 is connected to the exhaust channel 11. The exhaust channel 11 of all cylinders is generally connected to a common exhaust manifold 12 for all cylinders. The exhaust gas line 13 coming out of the exhaust manifold supplies the exhaust gas to the turbine 14 of the exhaust gas turbocharger 14, 15. The turbine 14 drives the compressor 15, which supplies the scuff compressed by the scavenge line 16 to the supercharged air distribution pipe 6. The scavenging cooler 17 may be disposed in the scavenging line 16.

The exhaust gas leaving the turbine 14 is discharged to the outside. In order to keep the NO _x component of this exhaust gas as low as possible, a part of the gas generated in the combustion chamber 2 during combustion is returned (recycled) directly or indirectly back to the combustion chamber 2. The recirculation line 18 provided for this purpose is connected to a recirculation gas collecting chamber 19 which branches in the region of the flue gas vent 20 and is continuous up to all cylinders 1 and recycles. In order to cool and / or clean and / or filter the exhaust recycle gas by one line section of the line 18, the recycle gas recovery chamber is in turn carried out via an optional treatment unit 21 via a charge air distribution line 6. ) The recirculation line 18 is therefore connected to an intake slot 4 which in turn acts as a charge air intake.

In the case of the apparatus based on FIG. 1, the recycle gas is mixed into the scavenging or scavenging gas and supplied as boost air, ie indirectly to the combustion chamber 2. Recirculation line 18 is connected to the charge air distribution line 6 for this purpose. The connection point of the recirculation line 18 may be arranged upstream of the cooler 17 as indicated by the dashed line in FIG. 1. In such a case, self cooling of the recycle gas may be removed.

Since the pressure of the recycle gas discharged from the combustion chamber 2 and supplied to the recirculation line 18 is higher than the scavenging pressure in the scavenging line 16, the flow is made automatically so that an additional pressure increase in the recirculation line 18 is achieved. No unit is needed. In order to reliably suppress backflow into the recirculation line 18 in the event of short-term peak pressure in the charge air, for example in each case in the region between the charge air distribution line 6 and the recycle gas recovery chamber 19 A check valve can be provided in the recirculation line 18, which is open toward the combustion chamber inlet.

A check valve 23 may in each case be provided in the recirculation line 18 in the region between the recirculation gas recovery chamber 19 and each combustion chamber 2, in addition to which it opens towards the combustion chamber inlet. It is. Therefore, at the same time, it is achieved that the combustion gas can flow through the recirculation line 18 only if the pressure on the combustion gas exhaust 20 side is higher than on the recycle gas recovery chamber 19 side. If the side pressure is lower than that of the recycle gas recovery chamber 19, the combustion gas recovered as the recycle gas therefrom does not flow back.

As already mentioned above, since the pressure of the combustion gas discharged from the combustion chamber 2 and recycled is higher than the charge air pressure, no further unit, for example a pump or a compressor, is necessary. To this end, the throttle device provided according to the invention makes a significant contribution.

Various variants of the flue gas recirculation system are already known and the flue gas recirculation system shown in FIG. 1 is merely exemplary here. For example, a plurality of members can be provided in plural which are comparable to those already mentioned, so that parallel operation can be ensured. Some of the illustrated members may be divided into functionally separated, serially arranged units, so that the desired function can be achieved during operation of the internal combustion engine under discussion. In addition, such a system may form the core of an expansion system having, for example, other members downstream or upstream of the turbine 14, so that the energy contained in the exhaust gas may be further utilized or finally externally. The exhaust gas can be purified before going out. Air flow rates upstream / downstream of members such as compressor 15 may be subjected to further processing via devices not shown in FIG. 1. Since components distinguished from pure external air may be mixed in the air flow rate, after the scavenging gas containing other, gaseous, combustible or non-combustible components is provided instead of pure scavenging, the combustion gas recycled may be purged of the cylinder. To the gas stream provided for At the end, the gas mixture provided for the scavenging of the cylinder may have a broad spectrum composition and is referred to as "charge air". The invention can of course be used in all combustion gas recirculation systems of that kind.

In this case, the first embodiment of the combustion gas exhaust port including the throttle device 10 of the type described above can be grasped in FIGS. 2 and 3. The state in which the combustion chamber 2 is separated from the exhaust channel 11 by the closing of the exhaust valve 9 is shown in FIG. 2. In contrast, the fully open position of the exhaust valve 9 is indicated by a broken line. The exhaust valve 9 therefore moves up and down in accordance with the control time clocked in the movement of the piston 3 as indicated by the thick arrows in both directions.

In this case the valve disc 8 in the exhaust valve 9 is placed on the disc seat in the closed position, thereby closing the combustion gas exhaust port 20 and closing the combustion gas exhaust port 20 during the downward movement of the valve 9. Open. In this case the valve disc 8 is fixed to the valve stem 7, which is again supported by the cylinder head as is conventionally and is generally driven by a camshaft-not shown here-and other valve actuating devices. It is also possible to consider, in particular, the emerging electronic valve direct control device, including, for example, valve actuation by an electromagnet or the like, according to the so-called electromagnetic valve control principle without mechanical coupling between the crankshaft and the valve stem. can see.

In this case, a rotationally symmetrical throttle protrusion 10 is provided on the valve stem 7, more precisely the throttle protrusion 10 is arranged when the exhaust valve 9 is closed (FIG. 2) and is in flow view. In the region arranged downstream of the branch of the recirculation line 18 from the exhaust port channel 11 to the desired constant opening degree (FIG. 3). The outer circumference of the throttle protrusion 10 in the region between the position shown in FIG. 2 and the position shown in FIG. 3 of the exhaust valve 9, which corresponds to the recirculation opening region of the exhaust valve 9, The exhaust channel 11 is closed, at least for the combustion gas actually coming out of the combustion chamber 2, in contact with the inner circumference of the cylindrical region, which closure need never be forced to the extent that the throttling effect important to the invention is achieved.

The combustion gas flowing out of the combustion chamber 2 at this stage is therefore diverted towards the recirculation line 18 as indicated by the arrows in FIG. 3, and for this purpose the hyperbola on the side opposite the combustion chamber 2 in the throttle projection 10 is shown. A circular or also rounded diameter extension 22 which contributes to the face or rounded surface and around the exhaust channel 11 in the region of the branch of the recirculation line 18 contributes.

In such a case, when the exhaust valve 9 moves downward from the position shown in FIG. 3 to the fully open position (indicated by the broken line in FIG. 2) of the desired opening degree defining the upper limit of the recirculation opening region, the throttle projection 10 Reaches the branching region and diameter expansion region of the recirculation line 18, through which the gas flowing out of the combustion chamber 2 can pass through the throttle protrusion through the combustion gas exhaust port 20 which is fully open.

In this case the embodiment shown in the figures is particularly advantageous in several respects. Therefore, between the position shown in FIG. 2 of the exhaust valve 9 and the position shown in FIG. 3, that is, during the initial opening phase in the recirculation or combustion gas discharge opening region, there is pure or nearly pure combustion gas in the combustion chamber 2. In this step, the passage of the air intake slot 4 has not been made or at least not yet made, and the combustion gas has a large pressure. Therefore, the combustion gas flowing into the recirculation line 18 has the desired characteristics for recycling, i.e. the gas in the scavenging system, ie the scavenging gas or the combustion gas flowing into the recycling line 18, is mixed. Since it has an overpressure relative to the pressure, the check valve 23 in the recirculation line 18 is opened as shown in FIG. On the other hand, the desired low oxygen concentration of the combustion gas also increases after the opening of the air intake slot 4 and the charging air.

In the subsequent exhaust gas discharge opening stage, ie, as indicated by the broken line in FIG. 2, upon opening of the exhaust valve 9, the piston 3 has passed through the supercharged air intake slot 4, thus the gas mixture in the combustion chamber 2. It has a low pressure that is detrimental to this recycling. This gas mixture now reaches the inlet region of the exhaust channel 11 and in the region of the diameter extension 22 when the combustion gas vent 20 is opened, in which case the throttle protrusion 10 in the diameter extension is Located. Therefore, bypassing of the throttle protrusion 10 is possible, but in this case no significant dynamic pressure acts on the gas flowing out of the combustion chamber 2. This gas usually flows out of the combustion chamber because the pressure in the exhaust manifold 12 is in principle lower than the boost air pressure. Therefore, the gas mixture cannot enter the recirculation line 18 or open the check valve 23 during the exhaust gas outlet opening step, but rather bypasses the throttle projection or the throttle body 10 toward the exhaust manifold 12. The result is excluded from recycling.

In another embodiment of the present invention shown in FIGS. 4 and 5 a modified branch region of the recirculation lines 118a, 118b branching from the slightly modified exhaust valve 109 and the exhaust channel 11 is used, but the combustion chamber (2) may be essentially the same as compared with the embodiment shown in Figs. 1 to 3, which is also valid for the other engine parts shown in Fig. 1.

In this case, the valve stem 107 is also provided with a circular throttle protrusion 110. However, this throttle protrusion is disposed immediately downstream of the valve seat 108. At the same time, the branches of the recycle line or in this case the branches of the recycle lines 118a and 118b are located directly in the connection area with the combustion gas exhaust port 120. In this case, the combustion gas exhaust port 120 is formed in the recirculating open position of the exhaust valve 109 shown in FIG. 4 via the valve disk seat behind the valve disk 108 and the combustion chamber wall, while the combustion gas exhaust port 120 Is formed between the valve disc seat and the rear and radial outward of the throttle protrusion or throttle disc 110 in the exhaust gas discharge open position of the exhaust valve 109 shown in FIG.

As in the first embodiment of the present invention, the throttle protrusion 110 is also disposed here downstream of the branches 118a and 118b of the recycle line in the exhaust channel 11 in the case of an exhaust valve 109 located in the recycle opening region. Since at least the closed area is closed at least mostly, the combustion gas in the recirculation opening area of the exhaust valve, which flows out of the combustion chamber 2, is led into the recirculation lines 118a, 118b as indicated by the arrows in FIG. 4. A check valve is provided in each case as shown in FIGS. 4 and 5 in the individual recirculation lines or in the area of the recirculation line through the respective recirculation lines 118a and 118b, which is provided in the recirculation line of FIG. 4. In (118b) it is not shown for space reasons. Only when the combustion gas has a higher pressure than the recycle gas collected in the recovery vessel 19, the check valves allow the introduction of recycle gas or combustion gas into the recycle recovery vessel 19.

In contrast, if the exhaust valve 108 has a larger opening or if the exhaust valve is located in the exhaust gas discharge opening region, the circular throttle protrusion 110 no longer closes the exhaust channel 11, Existing gas flows into the exhaust channel 11 and from there into the exhaust manifold 12, indicated by arrows in FIG. 5. Not only can two recycle lines 118a and 118b be provided to improve the inflow of combustion gas towards the recycle, but rather at this point a number of recycle lines distributed to the circumference of the cylindrical outlet channel 11 can be provided. Note that it may be. Thus, a circular circumferential recess may be provided in the inner wall, and recirculation lines 118 emerge from this circumferential recess.

Finally, when the exhaust valve 308 is closed (FIG. 6), when the exhaust valve is opened in the recirculation region (FIG. 7) and when the exhaust valve is opened in the exhaust gas discharge region (FIG. 8). An embodiment is shown in FIGS. 6 to 8.

In this embodiment the throttle device consists of a stage 310 protruding from the rear of the valve disc 308, the stage having a desired opening from the closed position of the exhaust valve 309 shown in FIG. 6, in FIG. 7. The exhaust channel 11 is closed in the recirculation opening region up to the position of the illustrated exhaust valve but the recirculation line 318 or exhaust channel (for inlet of the combustion gas flowing out of the combustion chamber 2 through the combustion gas exhaust port 320) 11) Open the branch 318a circulating around or the inlet 318a circulating around the exhaust channel 11. In contrast, the exhaust valve 307 moves into the combustion chamber in the exhaust gas discharge region shown in FIG. 8 so that stage 310 is no longer adjacent to the cylindrical wall of the exhaust channel 11 at a point corresponding to the recycle opening region. Rather, it opens the exhaust channel 11. As described above, a check valve can also be provided in recirculation line 318 in this case.

In an embodiment the material located between the combustion chamber wall and the recirculation line 318 or branch 318a because an inlet or branch 318a into the recycle line 318 is disposed directly at the exhaust port 320 of the combustion chamber 2. Are exposed to large heat loads, and at the same time the material web is very thin. In order to reduce this disadvantage, the embodiment of the present invention shown in Figs. 6 to 8 may be slightly modified as shown in Fig. 9.

In this case a coolant channel 24 is provided in the material web between the combustion chamber side surface and the inlet 418a of the recirculation line 418, which also passes around the exhaust channel 11. At the same time, the recovery volume of the recycle inlet 418a and the inlet region of the recycle line 418, which are open inwardly of the material, also lie slightly back into the material from the combustion chamber, so that a wider material web is shown in FIGS. 6 to 8. It withstands high heat loads even better than in the present embodiment of the present invention. Further in this case a rotary blade ring, which is well known in the art at the valve stem 307, is indicated by reference numeral 25, which causes the rotational movement of the valve by the passing gas. The valve rotational movement prevents premature wear of the exhaust valve 309 and the disc seat.

로 제공된 피스톤(3) 운동의 함수로서 소기 가스 흡기구(4)를 형성하는 흡기구 슬롯의 영역에서 유로 자유 횡단면의 곡선이 곡선(b)을 통해 도시되어 있다. 그에 반해 곡선(a)은 연소 가스 배기구(20)의 영역에서 유로 자유 횡단면의 곡선을 보여준다. 이 경우 캠축에 의해 구동되는 배기 밸브(9)의 경우 곡선은 실선으로 표시된 반면, 전자 방식으로 제어되는 그리고 크랭크축과 밸브 스템 사이에 기계적인 커플링 없이 작동되는 배기 밸브의 경우에 유로 자유 횡단면의 가능한 곡선들은 점선으로 표시되어 있다.For an internal combustion engine according to the invention, for example and purely according to OT (crank angle after top dead center) in FIG.

The curve of the flow path free cross section in the region of the inlet slot forming the scavenging gas inlet 4 as a function of the piston 3 movement provided by is shown through curve b. In contrast, curve a shows the curve of the flow path free cross section in the region of the combustion gas exhaust 20. In this case the curve for the exhaust valve 9 driven by the camshaft is indicated by the solid line, while in the case of the exhaust valve which is electronically controlled and operated without mechanical coupling between the crankshaft and the valve stem, Possible curves are indicated by dashed lines.

The opening of the exhaust valve 9 actuated by the camshaft is according to curve (a) during downstroke, for example at about 115 ° KW after top dead center, ie 65 ° above bottom dead center. In the case of an electronically controlled and actuated exhaust valve, the opening may start slightly earlier, for example at about 110 ° KW after top dead center and then stopped, so that the combustion gas exhaust opening area is fully opened and exhausted after the extension. The valve moves to the exhaust gas discharge area.

 The scavenging gas intakes 4 open according to curve b at about 135 ° after OT (45 ° above bottom dead center during downstroke). If the engine formed by the piston 3 and the crankshaft is actually symmetrical, the scavenging gas intake 6 is closed again at about 135 ° before OT in the upstroke of the piston 3. The closing of the exhaust valve 9, which is often controlled asymmetrically with respect to top dead center, takes place slightly later on the upstroke, so that the working chamber 2 is reliably scavenged when the exhaust valve 9 is opened. In this case, the combustion gas is no longer discharged, i.e. there is no combustion gas discharge opening area in the case of upstroke of the piston, so that the control of the electronically controlled exhaust valve corresponds to the normal exhaust valve operated by the camshaft. Can be done.

The gas leaking upon opening of the exhaust valve 9 causes an increase in the pressure in the exhaust channel 11. In curve c of FIG. 10, the pressure curve in the exhaust channel 11 is plotted according to the piston motion, ie according to the crank angle. It can be seen from this that the pressure in the exhaust channel 11 suddenly increases when the exhaust valve 9 is opened. This results in a pressure surge (e) starting at about 115 ° KW after OT, with one or more peaks. This pressure surge e exists for a relatively short time and only extends over about 20 ° KW. Therefore, the pressure surge e ends before opening of the inlet slot 4. Opening the scavenging gas intake 4 will in all cases lead to the final termination of the pressure surge e.

In the other curve d shown in FIG. 10, the pressure curve in the combustion chamber 2 is drawn according to the crank angle. Since the pressure in the combustion chamber 2 becomes relatively large, in this case, a magnitude different from the curve c in the longitudinal axis, which is the pressure axis, is applied to the curve d. Curves c and d intersect in FIG. 10. But this is only based on other sizes. If the same magnitude is used, the curves c and d will not intersect or at most will intersect in the region of the pressure surge e. According to curve a (FIG. 11), the exhaust valve 9 is fully opened from about 130 ° KW after OT. The pressure in the combustion chamber 2 and in the exhaust channel 11 is therefore approximately equal from about 150 ° KW after OT to 180 ° KW after OT after the end of the pressure surge e. According to the curve (b) from about 160 ° KW after OT, the scavenging gas intake port 4 is completely open.

The pressure in the combustion chamber 2 and in the exhaust channel 11 is thus only slightly smaller than the scavenging gas pressure, which is explained by the curve f in FIG. 10, which means the pressure in the scavenging system and the curve ( It is the same size as c). It can be clearly seen in this case that a positive pressure difference is obtained since the pressure in the exhaust channel exceeds the pressure f in the scavenging system immediately after the opening of the exhaust valve 9, the positive pressure difference being the combustion gas according to the invention. Is used to push into the flue gas discharge channel system and into the flue gas recirculation circuit ending with the intake vent somewhere in the scavenging gas system. Note that in this case, because of the larger volume that may be compressed directly downstream of the exhaust valve immediately after actuation of the exhaust valve, the shape of curve (c) is much flatter at e and without the throttle device of the present invention only a smaller maximum pressure value is achieved. Will be obtained.

It is clear from g that the scavenging gas pressure f for scavenging is above the actual pressure in the exhaust channel and then in the exhaust gas exhaust system. If the scavenging inlets open to the combustion chamber, there is a positive pressure difference transmitted by the cylinder volume between the scavenging system and the exhaust gas exhaust system during this step, so this scavenging causes the inlet gas to flow into the cylinder volume through the inlets. And through the open exhaust valve, causing simultaneous release of combustion gases.

Modifications and variations of the illustrated embodiments are possible without departing from the scope of the invention.

Thus, for example, the valve rotation mechanism is not necessary for the function of the recirculation control device, but may be provided in the embodiments shown in FIGS. 1 to 7. However, without such a rotating mechanism, the throttle device, which is in the form of an area protruding from the throttle disk, the sliding sleeve or the valve disk, and the area of the exhaust channel assigned thereto, may have completely different geometry. In the embodiments shown, the regions protruding from the throttle disk, the sliding sleeve or the valve disk and the area of the exhaust channel assigned thereto are symmetrically formed in any radial direction with respect to the valve axis.

The exhaust valves according to the invention can of course also be assembled in one piece, ie integrally or in multipiece, and the other members can also be fastened to it, for example the rotary blade ring 25 or other members. It is important that the exhaust valve is always controlled and exercised as a whole unit. The cylinder head can also be made up of individual members to be one assembly, which in particular can be adapted to the respective functions and / or boudoirs, for example to implement a water cooling ring line 24. . In addition, in all embodiments an actively controlled check valve or passive check valve can be provided in the combustion gas discharge channel or the recirculation line.

1: cylinder
2: combustion chamber
3: piston
4: intake slot
5: supply channel
6: distribution pipe
7; 107; 307: valve stem
8; 108; 308: valve disc
9; 109; 309; Exhaust valve
10; 110; 310: throttle device
10; 110: throttle protrusion
310: throttle stage
11: exhaust channel
12: exhaust manifold
13: exhaust gas line
14: turbine
15: compressor
14, 15: exhaust gas turbocharger
16: supercharge air line
17: Supercharged Air Cooler
18; 118a, 118b; 318, 318a; 418, 418a: combustion gas discharge channel
19: recycle gas recovery chamber
20: combustion gas exhaust port
21: Recirculating Gas Treatment Unit
22: diameter extension
23: check valve
24: water cooling ring line
25: rotating blade ring

Claims (29)

An internal combustion engine, in particular a large two-stroke diesel engine, comprising one cylinder (1) and one or more combustion chambers (2) limited by a piston (3) interacting with the crankshaft, the combustion chamber being an exhaust valve (9; 109; 309). And one or more combustion gas exhaust openings 20; 120; 320; 420 and one or more charge air intakes 4 formed between the valve disks 8; 108; 308 of the valve seat and the disk seats assigned thereto, and the exhaust valve 9 109; 309 may be operated between an open position and a closed position, and the combustion gas exhaust ports 20; 120; 320; 420 are connected to one or more exhaust channel 11 and also include one or more combustion gas exhaust channels ( 18; 118a, 118b; 318, 318a; 418, 418a, for example, internal combustion engines, in particular large two-stroke diesels, in which part of the combustion gases generated during combustion can be recycled to the charge air intake 4 In the engine,
There is provided a throttle device (10; 110; 310) fixed to the exhaust valve (9; 109; 309) or integrally molded together with the exhaust valve (9; 109; 309), the throttle device being provided with an exhaust valve (9; Inhibits the inflow of combustion gas into the exhaust channel 11 in the combustion gas discharge opening region of the exhaust valve 9; 109; 309 from the closed position to the desired opening, or from the larger opening to the open position. Throttling at least stronger than in the exhaust gas outlet opening region of the exhaust valves 9; 109; 309, in which the throttle device 10; 110; 310 is connected to the exhaust channel 11 An outlet side branch of the throttle device 10; 110; 310 and the combustion gas discharge channels 18; 118a, 118b; 318, 318a; 418, 418a, preferably throttling the inlet at least or at least less strongly Is in the combustion gas discharge opening region. Such that the throttle device 10; 110; 310 preferably does not throttle or at least significantly throttle the inlet of the combustion gas into the combustion gas discharge channels 18; 118a, 118b; 318, 318a; 418, 418a. Internal combustion engines, in particular large two-stroke diesel engines, characterized in that they are arranged. The method of claim 1,
Control of the exhaust valves 9; 109; 309 is such that the exhaust valves do not open before the piston position is reached during downstroke, which piston position is above the same piston position where the opening of the supercharged air intake 4 is used. Internal combustion engines, in particular large two-stroke diesel engines, characterized by a crank angle of at least 1 ° and at most 40 °. 3. The method according to claim 1 or 2,
The exhaust side branch of the throttle device and the flue gas discharge channel is arranged such that in the exhaust gas discharge opening region the throttle device is arranged to inhibit or minimally throttle the inlet of combustion gas into the flue gas discharge channel and / or the exhaust gas discharge opening. An internal combustion engine, in particular a large two-stroke diesel engine, characterized in that a check valve is provided in the combustion gas discharge channel to suppress or minimize throttling of the combustion gas into the combustion gas discharge channel in the region. 4. The method according to any one of claims 1 to 3,
Throttle arrangement (10; 110) has a throttle protrusion (10; 110), preferably circular, protruding radially from valve stem (7; 107) of exhaust valve (9), throttle protrusion (10; 110) Is provided in the region of the valve stem (7; 107), wherein the throttle projection is the combustion gas discharge channel (18; 118a, 118b) in terms of flow when the exhaust valve (9; 109) is open in the combustion gas discharge opening region. An internal combustion engine, in particular a large two-stroke diesel engine, characterized in that it is located in the region of the exhaust channel 11 arranged downstream of the branch on the exhaust port side, and the exhaust channel is preferably cylindrical in the region. 5. The method of claim 4,
The combustion gas discharge channel 18 is spaced apart from the combustion gas exhaust port 20 and branches in the exhaust channel 11, a throttle protrusion 10 is provided in the region of the valve stem 7, and the throttle protrusion is provided with an exhaust valve ( 9 in the exhaust gas outlet opening region is located approximately at the branch height of the combustion gas exhaust channel 18 in the exhaust channel 11 and in the region of the branch of the combustion gas exhaust channel 18. Has a circular diameter extension in particular, so that the throttle protrusion 10 preferably does not throttle the inlet of combustion gas into the exhaust channel 11 when the exhaust valve 9 is open in the exhaust gas discharge opening region. Or throttle at least less strongly than when the exhaust valve 9 is open in the combustion gas outlet opening region, in particular a large two-stroke D. Institutions. 5. The method of claim 4,
The throttle protrusion 110 is located in one region of the valve stem 107 located in the combustion chamber 2 when the exhaust valve 109 is open in the exhaust gas discharge opening region, and the combustion gas discharge channels 118a and 118b. An internal combustion engine, in particular a large two-stroke diesel engine, characterized in that the branch of is preferably located in the disc seat or in an area of the exhaust channel 11 directly adjacent the disc seat. 7. The method according to any one of claims 4 to 6,
The throttle protrusion 10; 110 has a diameter of the valve stem 7; 107 at any curvature at least in the region of the throttle protrusion 10; 110 opposite the valve disc 8; 108 of the throttle protrusion 10; 110. Internal combustion engine, in particular a large two-stroke diesel engine, characterized in that it transitions to the maximum radial outer dimension of a) and the throttle protrusion (10; 110) is preferably circular at the radial outer edge. 4. The method according to any one of claims 1 to 3,
The exhaust channel has an outlet cylinder disposed downstream of the combustion gas exhaust from a flow point of view, wherein at least one exhaust channel and at least one combustion gas exhaust channel branch off the outer circumference of the outlet cylinder, and the branch of the exhaust channel is a branch of the combustion gas exhaust channel. And a throttle device having a slide axially slidably accommodated in the outlet cylinder, the slide having at least one branch of the exhaust channel when the exhaust valve is open in the combustion gas exhaust opening region. An internal combustion engine, in particular a large two-stroke diesel engine, characterized in that it covers locally and is preferably fixedly connected to the exhaust valve to cover a branch of the combustion gas discharge channel when the exhaust valve is open in the exhaust gas discharge opening region. . 9. The method of claim 8,
The slide is formed as a cylindrical sliding sleeve, the sliding sleeve being connected to the valve stem of the rotatable exhaust valve, for example by a radial strut, the outlet cylinder is also cylindrical, preferably at the circumference of the outlet cylinder An internal combustion engine, in particular a large two-stroke diesel engine, characterized in that an exhaust channel is provided comprising an exhaust channel comprising a plurality of branches distributed and / or an exhaust channel branch open in a ring shape towards the outlet cylinder. 4. The method according to any one of claims 1 to 3,
The exhaust channel 11 has an outlet cylinder, preferably cylindrical, arranged downstream of the combustion gas exhaust port 420 in terms of flow and on which side the throttle device 310 orients the combustion chamber 2 of the valve disc 308. Preferably it has a stage 310 in the form of a cross section of the outlet cylinder which projects axially or at least with the axial component of the valve stem 307, in which the exhaust valve 309 opens in the combustion gas discharge opening region. The outlet cylinder is closed or at least narrowed, and the flue gas discharge channels 318, 318a; 418, 418a branch in a radially radial branching region outside of the stage 310, the branching region being an exhaust valve 309. Is closed by the orienting the combustion chamber 2 of the valve disc 308, and the valve disc extends outwards farther than the branching region in the radial direction, The gas discharge channels 318, 318a, 418, 418a are separated from the combustion chamber 2, and the branching region is preferably in the region adjacent to the stage 310 outward in the radial direction or at least the outer periphery of the stage 310. And the exhaust valve 309 is closed, the side of the valve disk 308, which orients the combustion chamber 2, is located in the disk seat, and the disk seat is radially farther outward than the branched area. Internal combustion engines, in particular large two-stroke diesel engines, characterized by an extension. 11. The method according to any one of claims 1 to 10,
The flue gas discharge channels 18; 318, 318a; 418, 418a are branched at the flue gas vents by branches 22; 318a; 418a, which open ring-shaped toward the outlet cylinder, the branches being preferably bead-like material. Internal combustion engines, in particular large two-strokes, characterized in that a combustion gas discharge channel 118a, 118b is provided which is open inward and / or comprises a plurality of branches 118a, 118b distributed on the circumference of the outlet cylinder. Diesel engine. 12. The method according to any one of claims 1 to 11,
Internal combustion engine, in particular a large two-stroke diesel engine, characterized in that in the region of the combustion gas vent 420 is provided a coolant line 24 which circulates at least locally in the material of the combustion chamber wall, in particular in the material behind the disc seat. The combustion gas exhaust port of the combustion chamber 2 limited by the piston 3 interacting with the cylinder 1 and the crankshaft in the internal combustion engine according to any one of claims 1 to 12, a large two-stroke diesel engine ( Exhaust valves 9; 109; 309 which open and close 20; 120; 320; 420, in order to form combustion gas exhaust ports 20; 120; 320; 420 with associated disc seats; 109; 309 has a valve stem 7; 107; 307 for operating the exhaust valve between an open and closed position and a valve disc 8; 108; 308 adjacent to the valve stem; In the exhaust valve for opening and closing
There is provided a throttle device (10; 110; 310) fixed to the exhaust valve (9; 109; 309) or integrally formed with the exhaust valve (9; 109; 309), the throttle device comprising an exhaust valve (9; 109 inhibits the inflow of combustion gas into the exhaust channel 11 in the combustion gas discharge opening region from the closed position of the exhaust valve 9; 109; 309 to the desired opening degree or from a larger opening. 109; 309 suitable for throttling at least stronger than in the exhaust gas outlet opening region up to the open position, wherein the throttle device 10; 110; 310 preferably provides for the inflow of combustion gas into the exhaust channel 11; Wherein the exhaust valve opens and closes the combustion gas exhaust port of the combustion chamber, characterized in that it is not throttling at all or at least less intensely. The method of claim 13,
Throttle arrangement (10; 110) is a radially and preferably circular throttle protrusion (10; 110) spaced from valve disc (8; 108), which projects radially from valve stem (7; 107) of exhaust valve (9). And the diameter of the valve stem (7; 107) is at least one curvature on the side of the throttle protrusion (10; 110) opposite the valve disc (8; 108) of the throttle protrusion (10; 110). An exhaust opening and closing the combustion gas exhaust of the combustion chamber, characterized in that it transitions to the maximum radial outer dimension of (10; 110), the throttle projection (10; 110) being preferably circular at the radially outer edge. valve. The method of claim 13,
The throttle device 310 preferably has a stage 310 protruding in the axial direction of the valve stem 307, or at least with the axial component, on the side of the valve disc 308 that orients the combustion chamber 2. 309 in the combustion chamber, characterized in that the valve disk 308 is located on the side of the valve disk 308 to orient the combustion chamber 2 to the area adjacent to the end 310 in the radial direction outward. Exhaust valve to open and close the combustion gas exhaust port. The method of claim 13,
The throttle device is in the form of a cylindrical sleeve which is axially movable within the outlet cylinder, in particular slidably accommodated in the inner circumference of the outlet cylinder and is connected to the valve stem of the exhaust valve, in particular by a radial strut, spaced from the valve disc. An exhaust valve for opening and closing the combustion gas exhaust port of the combustion chamber, characterized by having an in-slide. 17. The method according to any one of claims 13 to 16,
An exhaust valve for opening and closing the combustion gas exhaust port of the combustion chamber, wherein the valve stem 307 is provided with a valve rotation mechanism 25. 18. The method according to any one of claims 13 to 17,
In the valve stem, an identification mark is provided that can be read without contact at the end region of the combustion chamber, the identification mark corresponding to the valve path until reaching the transition region between the combustion gas exhaust opening region and the exhaust gas exhaust opening region. And at least one axial extension, wherein the identification mark preferably extends over the entire circumference of the valve stem. 13. Especially for an internal combustion engine according to claim 1, in particular a large two stroke comprising at least one combustion chamber 2 limited by a cylinder 1 and a piston 3 interacting with the crankshaft. A cylinder head for a diesel engine, the disc seat for the valve disc (8; 108; 308) of the exhaust valve (9; 109; 309) for opening and closing the combustion gas exhaust ports (20; 120; 320; 420) in the cylinder head. At the head, the flue gas outlets 20; 120; 320; 420 are connected to one or more exhaust channel 11 and to one or more flue gas outlet channels 18; 118a, 118b; 318, 318a; 418, 418a. Thus, for example, in a cylinder head for an internal combustion engine, in particular a large two-stroke diesel engine, in which part of the combustion gas generated during combustion is recycled to the supercharged air intake port 4,
An exhaust valve (9; 109; 309) according to any one of claims 13 to 18 is provided, the throttle device (10; 110; 310) and the combustion gas discharge channels (18; 118a, 118b; 318, The exhaust side branch of 318a; 418, 418a is characterized in that the throttle device 10; 110; 310 in the combustion gas discharge opening region allows combustion gas into the combustion gas discharge channels 18; 118a, 118b; 318, 318a; 418, 418a. For internal combustion engines, in particular large, characterized in that it is arranged so as not to throttle or at least considerably throttle the inflow of Cylinder head for two-stroke diesel engines. 13. Production of a large two-stroke diesel engine, in particular according to any one of the preceding claims, comprising one or more combustion chambers 2 defined by a cylinder 1 and a piston 3 interacting with the crankshaft. As a method, one or more combustion gas exhaust ports 20; 120; 320; 420 is provided in which the combustion chamber is in each case between the valve discs 8; 108; 308 of the exhaust valves 9; 109; 309 and the disc seats assigned thereto. And a method for manufacturing a large two-stroke diesel engine having one or more supercharged air intakes (4),
A method for producing a large two-stroke diesel engine, characterized in that an exhaust valve (9; 109; 309) according to any one of claims 13 to 18 is incorporated. 13. Production of a large two-stroke diesel engine, in particular according to any one of the preceding claims, comprising one or more combustion chambers 2 defined by a cylinder 1 and a piston 3 interacting with the crankshaft. As a method, one or more combustion gas exhaust ports 20; 120; 320; 420 is provided in which the combustion chamber is in each case between the valve discs 8; 108; 308 of the exhaust valves 9; 109; 309 and the disc seats assigned thereto. And a method for manufacturing a large two-stroke diesel engine having one or more supercharged air intakes (4),
20. A method for manufacturing a large two-stroke diesel engine, characterized in that the cylinder head according to claim 19 is incorporated. 22. The method according to claim 20 or 21,
A method for producing a large two-stroke diesel engine, characterized in that the large two-stroke diesel engine is produced for the first time. 22. The method according to claim 20 or 21,
In this case, a large two-stroke diesel engine manufacturing method, characterized in that the large two-stroke diesel engine continues to function. 24. The method of claim 23,
As the other conventional exhaust valves are replaced by the incorporation of the exhaust valves 9; 109 and 309 according to any one of claims 13 to 18 or the other conventional cylinder heads are replaced by the cylinder heads according to claim 19, A large large two-stroke diesel engine without the features of any of claims 1 to 12 is converted into a large two-stroke diesel engine according to any of the preceding claims. Manufacturing method of stroke diesel engine. Use of an internal combustion engine according to any one of the preceding claims in a structure for use in water, in particular a vessel, which is subject to a legal operation permit in accordance with a legal operating permit for the internal combustion engine. A current internal combustion engine, in particular large in accordance with claim 1, comprising at least one combustion chamber 2 limited by a cylinder 1 and a piston 3 interacting with the crankshaft. A method for discharging combustion gas from a two-stroke diesel engine, wherein the combustion chamber is in each case between the valve discs (8; 108; 308) of the exhaust valves (9; 109; 309) and the disc seats assigned thereto. Having a gas exhaust port 20; 120; 320; 420 and one or more charge air intakes 4, an exhaust valve 9; 109; 309 is operated between an open position and a closed position, and a combustion gas exhaust port 20; 120 320; 420 is connected to one or more exhaust channel 11 and one or more combustion gas channels 18; 118a, 118b; 318, 318a; 418, 418a, for example, combustion gas generated during combustion Combustion gas recirculated to a supercharged air intake 4 A method for the discharge,
The inflow of combustion gas into the exhaust channel 11 in the combustion gas discharge opening region of the exhaust valve 9; 109; 309 from the closed position of the exhaust valve 9; Exhaust valve 9, fixed to 109; 109 throttled at least more strongly than in the exhaust gas outlet opening region of 109; A method for venting combustion gases, characterized in that it is preferably not throttled at least or at least significantly throttled by the throttle device (10; 110; 310). The method of claim 26,
The inlet of the combustion gas into the combustion gas discharge region is suppressed or minimally throttled by an actively controllable or manual check valve provided in the throttle device and / or the combustion gas discharge channel in the exhaust gas discharge opening region A method of discharging combustion gas to be used. 28. The method of claim 26 or 27,
A method of evacuating combustion gas, characterized in that the control times of the throttle device are continuously readjusted when the exhaust valve is actuated electronically. 28. The method of claim 26 or 27,
A method for discharging combustion gas, characterized in that when the exhaust valve is actuated by a camshaft the amount of combustion gas discharged is controlled by a check valve which can be actively controlled in the combustion gas discharge channel.

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