DE4216759C1 - Reduction of nitrogen oxide(s) in exhaust gases from combustion engine - includes recycling exhaust gas during high load operation - Google Patents
Reduction of nitrogen oxide(s) in exhaust gases from combustion engine - includes recycling exhaust gas during high load operationInfo
- Publication number
- DE4216759C1 DE4216759C1 DE4216759A DE4216759A DE4216759C1 DE 4216759 C1 DE4216759 C1 DE 4216759C1 DE 4216759 A DE4216759 A DE 4216759A DE 4216759 A DE4216759 A DE 4216759A DE 4216759 C1 DE4216759 C1 DE 4216759C1
- Authority
- DE
- Germany
- Prior art keywords
- exhaust gas
- combustion engine
- nitrogen oxide
- high load
- during high
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Revoked
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D13/00—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
- F02D13/02—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing during engine operation
- F02D13/0223—Variable control of the intake valves only
- F02D13/0234—Variable control of the intake valves only changing the valve timing only
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D13/00—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
- F02D13/02—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing during engine operation
- F02D13/0269—Controlling the valves to perform a Miller-Atkinson cycle
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D21/00—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas
- F02D21/06—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air
- F02D21/08—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air the other gas being the exhaust gas of engine
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
- F02M26/01—Internal exhaust gas recirculation, i.e. wherein the residual exhaust gases are trapped in the cylinder or pushed back from the intake or the exhaust manifold into the combustion chamber without the use of additional passages
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B2275/00—Other engines, components or details, not provided for in other groups of this subclass
- F02B2275/32—Miller cycle
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B3/00—Engines characterised by air compression and subsequent fuel addition
- F02B3/06—Engines characterised by air compression and subsequent fuel addition with compression ignition
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Output Control And Ontrol Of Special Type Engine (AREA)
Abstract
Description
Die Erfindung betrifft ein Verfahren zur Reduktion der Stickoxide im Abgas einer aufgeladenen Brennkraftmaschine nach dem Oberbegriff des Patentanspruchs 1, wie es beispielsweise aus der DE-AS 24 54 829 als bekannt hervorgeht.The invention relates to a method for reducing the Nitrogen oxides in the exhaust gas of a supercharged internal combustion engine the preamble of claim 1, such as from the DE-AS 24 54 829 emerges as known.
Aus der eingangs genannten DE-AS 24 54 829 geht es als bekannt hervor, daß der Ausstoß von Stickoxiden im Abgas einer aufgeladenen Dieselbrennkraftmaschine durch Abgasrückführung reduziert werden kann. Die Rückführung von Abgasen führt jedoch zu einer Anhebung der Verbrennungstemperaturen, was die Stickoxidbildung wieder fördert. Es ist deshalb vorgesehen, die rückgeführten Abgase vor Eintritt in die Verbrennungsräume zu kühlen. Zur Kühlung der Abgase dient ein als Kompressor arbeitender Zylinder. Die von diesem Zylinder angesaugten Abgase geben in der Kompressionsphase ihre Wärme an das Kühlsystem der Brennkraftmaschine ab, bevor sie, auf den Druck der Frischluft in der Ansaugleitung entspannt, zusammen mit der Frischluft den übrigen Zylindern zugeführt werden. Der Aufwand zur Kühlung der Abgase in einem separaten Zylinder ist jedoch beträchtlich.From the aforementioned DE-AS 24 54 829 it is known shows that the emission of nitrogen oxides in the exhaust gas supercharged diesel engine through exhaust gas recirculation can be reduced. The return of exhaust gases leads however to an increase in combustion temperatures what the Promotes nitrogen oxide formation again. It is therefore intended that recirculated exhaust gases before entering the combustion chambers cool. A serves as a compressor for cooling the exhaust gases working cylinder. The exhaust gases sucked in by this cylinder give their heat to the cooling system in the compression phase Internal combustion engine before, on the pressure of the fresh air relaxed in the intake line, together with the fresh air be fed to other cylinders. The effort to cool the However, exhaust gases in a separate cylinder are considerable.
In der WO 88/01 016 ist beschrieben, zur Kühlung der Ladung Wasser in die Verbrennungsräume einer Dieselbrennkraftmaschine einzubringen, um dadurch eine Stickoxidreduktion zu erreichen. Um die Stickoxidreduktion noch zu steigern, wird das rückgeführte Abgas noch zusätzlich in Wärmetauschern gekühlt. Der Anteil an rückgeführtem Abgas beträgt etwa 20% des gesamten Abgasvolumens. Auch dieses Verfahren zur Temperaturerniedrigung ist sehr aufwendig, weil zum einen Einrichtungen zum Einbringen des Wassers und zum anderen Wärmetauscher zur Abgaskühlung vorgesehen werden müssen.WO 88/01 016 describes how to cool the load Water into the combustion chambers of a diesel engine in order to achieve a nitrogen oxide reduction. To increase nitrogen oxide reduction even more, recirculated exhaust gas is additionally cooled in heat exchangers. The proportion of recirculated exhaust gas is about 20% of the total Exhaust gas volume. This process for lowering the temperature is very complex because, on the one hand, facilities for insertion the water and the other heat exchanger for exhaust gas cooling must be provided.
Bei einer Brennkraftmaschine nach der EP 00 15 791 B1, die nach dem sogenannten Miller-Verfahren arbeitet, wird zur Verbesserung der Zündung bei Teillast Abgas rückgeführt, um die Ladung im Zylinder bei Teillast zu erwärmen. Mit der Ventilsteuerung nach dem Miller-Verfahren soll erreicht werden, daß mit zunehmender Last das Verdichtungsverhältnis abnimmt, wobei der rückgeführte Abgasanteil in den oberen Lastbereichen auf Null vermindert wird. Bei hoher Last ist also eine Erwärmung der Ladung nicht vorgesehen, weshalb in diesem Lastbereich keine Abgasrückführung erfolgt. Vielmehr würde bei dieser Brennkraftmaschine in hohen Lastbereichen eine Abgasrückführung zu thermischer Überbeanspruchung führen. Gerade bei aufgeladenen Brennkraftmaschinen ohne Abgasrückführung ist aber in hohen Lastbereichen wegen der hohen Temperaturen in den Brennräumen der Stickoxidausstoß besonders hoch.In an internal combustion engine according to EP 00 15 791 B1, which according to The so-called Miller process works for improvement the ignition is recirculated at part load to the charge in the Warm cylinder at partial load. With the valve control after the Miller process should be achieved that with increasing Load the compression ratio decreases, with the recirculated Exhaust gas content in the upper load ranges reduced to zero becomes. This means that the load does not heat up under high loads provided, which is why no exhaust gas recirculation in this load range he follows. Rather, this engine would be in high Exhaust gas recirculation to thermal load ranges Cause overuse. Especially with charged ones However, internal combustion engines without exhaust gas recirculation are in high Load ranges due to the high temperatures in the combustion chambers nitrogen oxide emissions are particularly high.
Der Erfindung liegt die Aufgabe zugrunde, die Stickoxidemission im Abgas von aufgeladenen Dieselbrennkraftmaschinen insbesondere bei hoher Last auf möglichst niedrigem Niveau zu halten.The invention is based, the nitrogen oxide emission in the exhaust gas of supercharged diesel engines in particular to be kept at the lowest possible level under high loads.
Diese Aufgabe wird erfindungsmäßig dadurch gelöst, daß die Einlaßorgane der Brennkraftmaschine in den hohen Lastbereichen entsprechend dem Miller-Verfahren vor Erreichen der unteren Totpunktlage des Kolbens im Ansaughub geschlossen werden.This object is achieved according to the invention in that the intake organs of the internal combustion engine in the high Load ranges according to the Miller method before reaching the bottom dead center position of the piston be closed in the intake stroke.
Dadurch wird die Ladung zunächst expandiert, was zu einer Erniedrigung der Verdichtungsendtemperatur führt. Durch Anwendung des Miller-Verfahrens kann somit eine Temperaturerhöhung durch die Abgasrückführung ausgeglichen werden, so daß auch in den oberen Lastbereichen ohne aufwendige Einrichtungen eine Reduzierung der Stickoxide erreicht werden kann. Das maximale Leistungsvermögen der Brennkraftmaschine wird dabei nicht erniedrigt, wenn durch Erhöhung des Ladeluftdrucks entsprechend dem Leistungsvermögen der Brennkraftmaschine die gleiche Frischluftmenge zugeführt wird, wie bei einer konventionellen Brennkraftmaschine mit konventioneller Ventilsteuerung, bei der nämlich das Einlaßventil nach dem Ende des Ansaughubs schließt. Bei dieser konventionellen Brennkraftmaschine würde aber eine Abgasrückführung ohne Kühlung zu thermischer Überbeanspruchung führen.This initially expands the cargo, leading to leads to a lowering of the compression temperature. By Applying the Miller method can thus be a Temperature increase compensated by the exhaust gas recirculation be, so that even in the upper load ranges without expensive Devices a reduction in nitrogen oxides can be achieved can. The maximum performance of the internal combustion engine is not decreased when increasing the charge air pressure according to the performance of the internal combustion engine the same amount of fresh air is supplied as with a conventional internal combustion engine with conventional Valve control, namely the inlet valve after the end of the intake stroke closes. With this conventional Internal combustion engine would, however, exhaust gas recirculation without cooling lead to thermal overload.
Eine Weiterbildung der Erfindung ist im Patentanspruch 2 dargelegt.A further development of the invention is set out in claim 2.
Ein Ausführungsbeispiel der Erfindung ist in der Zeichnung dargestellt und wird im folgendem näher erläutert.An embodiment of the invention is in the drawing shown and is explained in more detail below.
Es zeigt die einzige Figur die Ventilerhebungskurven eines Ein- und eines Auslaßventils eines Zylinders einer Brennkraftmaschine bei hoher Last.It shows the only figure shows the valve lift curves of one and one Exhaust valve of a cylinder of an internal combustion engine at high Load.
Die Kurve 1 in der einzigen Figur zeigt die Ventilerhebung eines Auslaßventils einer Brennkraftmaschine und die Kurve 2 die Ventilerhebung des Einlaßventils desselben Zylinders. Das Auslaßventil öffnet vor dem unteren Totpunkt (UT) und schließt nach dem oberen Totpunkt (OT). Das Einlaßventil öffnet vor dem oberen Totpunkt und schließt entsprechend dem Miller-Verfahren vor Erreichen des unteren Totpunkts wieder. Die Überschneidung von Ein- und Auslaßventil ist nur gering, so daß eine intensive Durchspülung des Zylinders nicht erfolgt. Es wird dadurch erreicht, daß Restabgas im Zylinder verbleibt. Die im Zylinder verbleibende Restabgasmenge kann je nach Lastzustand durch Änderung der Überschneidung geändert werden. Natürlich ist es zur Abgasrückführung statt dessen auch möglich, einen Teil der den Zylinder verlassenden Abgase durch eine Verbindungsleitung in die Ansaugleitung vor den Zylindern zurückzuführen.Curve 1 in the single figure shows the valve lift of an exhaust valve of an internal combustion engine and curve 2 the valve lift of the intake valve of the same cylinder. The exhaust valve opens before bottom dead center (UT) and closes after top dead center (OT). The inlet valve opens before top dead center and closes again according to the Miller method before reaching bottom dead center. The overlap of the intake and exhaust valve is only slight, so that there is no intensive flushing of the cylinder. It is achieved in that residual exhaust gas remains in the cylinder. The amount of residual exhaust gas remaining in the cylinder can be changed depending on the load condition by changing the overlap. For exhaust gas recirculation, it is of course also possible instead to return part of the exhaust gases leaving the cylinder through a connecting line into the intake line in front of the cylinders.
Durch Abgasrückführung kann bekanntlich die Stickoxidemission beim Dieselmotor gesenkt werden. Es besteht jedoch der Nachteil, daß mit zunehmender Last die Frischladung zunehmend durch das rückgeführte Abgas bzw. das im Zylinder verbliebene heiße Restgas erwärmt wird und die daraus resultierende höhere Maximaltemperatur die Stickoxidbildung fördert. Durch Anwendung des Miller-Verfahrens kann diese Temperaturerhöhung vermieden werden. Das Einlaßventil wird, wie in der Figur dargestellt, vorzeitig, d. h. vor dem unteren Totpunkt geschlossen, so daß das Gemisch aus Restgas und Frischgas durch Expansion zunächst gekühlt wird. Die Kompression beginnt dann bei einer geringeren Temperatur und führt zu einer entsprechend geringeren Maximaltemperatur der Brenngase. Die notwendige Frischluftmasse kann durch Erhöhung des Ladeluftdrucks entsprechend dem Leistungsvermögen der Brennkraftmaschine zugeführt werden.As is well known, exhaust gas recirculation can reduce nitrogen oxide emissions be lowered in the diesel engine. However, there is the disadvantage that with increasing load, the fresh charge increasingly through the recirculated exhaust gas or the hot remaining in the cylinder Residual gas is heated and the resulting higher Maximum temperature that promotes nitrogen oxide formation. By application the Miller process can avoid this temperature increase will. The inlet valve is, as shown in the figure, prematurely, d. H. closed before bottom dead center, so that the mixture of residual gas and fresh gas by expansion initially is cooled. The compression then starts at a lower one Temperature and leads to a correspondingly lower Maximum temperature of the fuel gases. The necessary fresh air mass can be increased by increasing the charge air pressure accordingly Capacities of the internal combustion engine are supplied.
Zur Optimierung des Verfahrens im Kennfeld ist eine variable Ventilsteuerung zweckmäßig.A variable is used to optimize the procedure in the map Valve control useful.
Claims (2)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE4216759A DE4216759C1 (en) | 1992-05-21 | 1992-05-21 | Reduction of nitrogen oxide(s) in exhaust gases from combustion engine - includes recycling exhaust gas during high load operation |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE4216759A DE4216759C1 (en) | 1992-05-21 | 1992-05-21 | Reduction of nitrogen oxide(s) in exhaust gases from combustion engine - includes recycling exhaust gas during high load operation |
Publications (1)
Publication Number | Publication Date |
---|---|
DE4216759C1 true DE4216759C1 (en) | 1993-02-18 |
Family
ID=6459376
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
DE4216759A Revoked DE4216759C1 (en) | 1992-05-21 | 1992-05-21 | Reduction of nitrogen oxide(s) in exhaust gases from combustion engine - includes recycling exhaust gas during high load operation |
Country Status (1)
Country | Link |
---|---|
DE (1) | DE4216759C1 (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1362989A3 (en) * | 2002-05-14 | 2007-09-26 | Caterpillar Inc. | control system and method for variable valve actuation system |
WO2008006476A1 (en) | 2006-07-14 | 2008-01-17 | Daimler Ag | Method for operating a spark-ignition engine |
EP2136054A1 (en) * | 2008-06-18 | 2009-12-23 | Caterpillar Motoren GmbH & Co. KG | Method and device for controlling the operation of an internal combustion engine |
US8215292B2 (en) | 1996-07-17 | 2012-07-10 | Bryant Clyde C | Internal combustion engine and working cycle |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2454829B2 (en) * | 1973-11-28 | 1976-11-18 | S.A. de Vehicules Industrieis et d'Equipements Mecaniques Saviem, Suresnes, Hauts-de-Seine (Frankreich) | MULTI-CYLINDER COMBUSTION ENGINE |
EP0015791A1 (en) * | 1979-02-05 | 1980-09-17 | Societe D'etudes De Machines Thermiques S.E.M.T. | Method and device for improving the efficiency of an internal-combustion engine, in particular a supercharged one |
-
1992
- 1992-05-21 DE DE4216759A patent/DE4216759C1/en not_active Revoked
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2454829B2 (en) * | 1973-11-28 | 1976-11-18 | S.A. de Vehicules Industrieis et d'Equipements Mecaniques Saviem, Suresnes, Hauts-de-Seine (Frankreich) | MULTI-CYLINDER COMBUSTION ENGINE |
EP0015791A1 (en) * | 1979-02-05 | 1980-09-17 | Societe D'etudes De Machines Thermiques S.E.M.T. | Method and device for improving the efficiency of an internal-combustion engine, in particular a supercharged one |
Non-Patent Citations (1)
Title |
---|
DE-Z.: "MTZ" 31, 1970, Heft 1, S. 1-10 * |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8215292B2 (en) | 1996-07-17 | 2012-07-10 | Bryant Clyde C | Internal combustion engine and working cycle |
EP1362989A3 (en) * | 2002-05-14 | 2007-09-26 | Caterpillar Inc. | control system and method for variable valve actuation system |
WO2008006476A1 (en) | 2006-07-14 | 2008-01-17 | Daimler Ag | Method for operating a spark-ignition engine |
US8100115B2 (en) | 2006-07-14 | 2012-01-24 | Daimler Ag | Method for operating a spark ignition engine |
EP2136054A1 (en) * | 2008-06-18 | 2009-12-23 | Caterpillar Motoren GmbH & Co. KG | Method and device for controlling the operation of an internal combustion engine |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
DE69912019T2 (en) | Monitored auto-ignition combustion process and associated 4-stroke internal combustion engine with transfer line between cylinder and valve for it | |
DE102008042872B4 (en) | Compression ignition engine with homogeneous charge | |
DE3125647C2 (en) | ||
DE102004045967A1 (en) | A homogeneous charge compression internal combustion engine that performs an EGR and an ignition timing control method for the engine | |
DE102012106343A1 (en) | Method and system for a turbocharged engine | |
DE10102377A1 (en) | Strategy for engine control using double even cam phasing combined with exhaust gas recirculation | |
DE3437330A1 (en) | AIR-COMPRESSING, SELF-IGNITION OR FORD-IGNITIONED 4-STROKE COMBUSTION ENGINE WITH DIRECT FUEL INJECTION, TURBOCHARGING AND LOAD-RELATED INTERNAL EXHAUST GAS RECIRCULATION | |
WO2012045452A2 (en) | Operational method with water injection | |
DE102012106353A1 (en) | Turbocharged engine cylinder operating method for propulsion system of passenger vehicle, involves recirculating amounts of exhaust gases at two different pressures from two exhaust passages of cylinder to two intake passages, respectively | |
DE102011105530B4 (en) | Diesel engine for a vehicle and corresponding method | |
DE102012106327A1 (en) | Method of operating turbocharged engine used for passenger vehicle, involves driving intake compressor by exhaust turbine to provide boosted intake aircharge to cylinder through upper intake passage | |
WO2015110257A2 (en) | Reciprocating piston internal combustion engine, and method for operating a reciprocating piston internal combustion engine | |
DE3935367C2 (en) | ||
DE4216759C1 (en) | Reduction of nitrogen oxide(s) in exhaust gases from combustion engine - includes recycling exhaust gas during high load operation | |
DE2125368A1 (en) | Four-stroke engine and method of reducing harmful components in its exhaust gases | |
DE19905636A1 (en) | Reduction of temperature in combustion chamber of internal combustion engine with inlet valve partially opened during suction cycle to generate cooling effect on combustion mixture | |
AT6341U1 (en) | METHOD FOR OPERATING A MULTI-CYLINDER INTERNAL COMBUSTION ENGINE | |
WO2004031559A1 (en) | Self-igniting internal combustion engine | |
DE102019134628B4 (en) | Method and control device for operating an engine designed as a gas engine or dual-fuel engine | |
DE102008053243A1 (en) | Method for operating internal combustion engine, particularly with fuel direct injection, particularly for motor vehicle, involves connecting inlet valve and outlet valve for controlling gas-exchange cycle | |
DE10306457B4 (en) | Method and device for increasing the heating power in motor vehicles with internal combustion engines | |
DE4038463A1 (en) | Piston engine cylinder head - feeds fuel and superheated steam into pre-compressed combustion air | |
DE3323337A1 (en) | DIESEL INTERNAL COMBUSTION ENGINE | |
DE3931379A1 (en) | IC engine with external compressor - with greater part of compression occurring in compressor | |
EP4253738B1 (en) | Method for operating a cyclically driven piston motor |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
8100 | Publication of the examined application without publication of unexamined application | ||
D1 | Grant (no unexamined application published) patent law 81 | ||
8363 | Opposition against the patent | ||
8331 | Complete revocation |