EP0252316A1 - Internal combustion engine with pressure wave charging and a lambda probe - Google Patents

Internal combustion engine with pressure wave charging and a lambda probe Download PDF

Info

Publication number
EP0252316A1
EP0252316A1 EP87108266A EP87108266A EP0252316A1 EP 0252316 A1 EP0252316 A1 EP 0252316A1 EP 87108266 A EP87108266 A EP 87108266A EP 87108266 A EP87108266 A EP 87108266A EP 0252316 A1 EP0252316 A1 EP 0252316A1
Authority
EP
European Patent Office
Prior art keywords
pressure
exhaust gas
lambda probe
internal combustion
combustion engine
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.)
Granted
Application number
EP87108266A
Other languages
German (de)
French (fr)
Other versions
EP0252316B1 (en
Inventor
Andreas Mayer
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Comprex AG
Original Assignee
BBC Brown Boveri AG Switzerland
Comprex AG
BBC Brown Boveri France SA
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by BBC Brown Boveri AG Switzerland, Comprex AG, BBC Brown Boveri France SA filed Critical BBC Brown Boveri AG Switzerland
Priority to AT87108266T priority Critical patent/ATE59432T1/en
Publication of EP0252316A1 publication Critical patent/EP0252316A1/en
Application granted granted Critical
Publication of EP0252316B1 publication Critical patent/EP0252316B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • 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
    • F02B33/00—Engines characterised by provision of pumps for charging or scavenging
    • F02B33/32—Engines with pumps other than of reciprocating-piston type
    • F02B33/42—Engines with pumps other than of reciprocating-piston type with driven apparatus for immediate conversion of combustion gas pressure into pressure of fresh charge, e.g. with cell-type pressure exchangers

Definitions

  • the present invention relates to the circuitry of an internal combustion engine charged with a pressure wave supercharger according to the preamble of claim 1.
  • a “lambda probe” is installed between the engine and the exhaust gas particle filter as an oxygen sensor, the measurement signal of which is fed to a control system of the internal combustion engine, which is suitably adapted to the fresh air supply and / or the amount of fuel.
  • a “lambda probe" with a ZRO2 ceramic suitable for measuring the oxygen content in the exhaust gas of internal combustion engines relative to the oxygen content of the air is, for example, from the article by Hans-Martin Wiedenmann et al., "Heated Zirconia Oxygen Sensor for Stoichiometric and Lean Air- Fuel Ratios ", SAE Paper 840141, SAE Congres, Detroit, February-March 1984.
  • the oxygen partial pressure in the exhaust gas changes with the exhaust gas pressure.
  • the pressure of the exhaust gas in the exhaust system of an internal combustion engine is by no means constant, but depends strongly on the degree of clogging of the exhaust gas particle filter and the engine speed. With supercharged internal combustion engines, the pressure fluctuations in the exhaust system are still a lot greater, since the respective engine charge and the degree of clogging of the exhaust gas particle filter are added to the influences mentioned.
  • the pressure correction which could eliminate the influence of the exhaust gas pressure on the measurement signal of the lambda probe, requires the use of a pressure sensor and an electronic computer unit.
  • this is a complex solution because the pressure sensor in the exhaust system must be extremely corrosion-resistant.
  • the other precaution namely the installation of the lambda sensor in a bypass partial flow in the exhaust system, also proves to be a complex solution, be it in the circuit-appropriate installation of the auxiliary measure or in terms of the means used.
  • the invention solves the problem of providing for the direct installation of the lambda probe at a location of the circuit where the oxygen content to be measured is immediately available in an information-correct manner.
  • the advantages of the placement of the lambda probe according to the invention can essentially be seen in the fact that a faster response time of the lambda probe is achieved in the full flow of the low-pressure exhaust gases, because there flows more volume than in a bypass partial flow.
  • a pressure correction can also be dispensed with when measuring in full flow of the low-pressure exhaust gases because there are no pressure fluctuations.
  • the circuit shown in FIG. 1 consists of a motor 1, a pressure wave charger 2, an exhaust gas particle filter 3.
  • a throttle valve 4, which is adjusted by a servomotor 5, is placed in the air intake line 111 to the pressure wave charger.
  • a start valve or an automatic charge air flap 6 is placed in the line for the fresh air supply 222 to the engine 1.
  • the exhaust gas particle filter 3 is in the high-pressure exhaust gas line 333 installed, ie between engine 1 and pressure wave charger 2.
  • a lambda probe 7 acts in the low-pressure exhaust gas line 444, the arrangement of which is provided separately from a possible purge flow, preferably in the opening area of the low-pressure gas outflow channel 26 (FIG. 2).
  • the lambda probe 7 determines the oxygen content in the exhaust gas after it has performed charging work in the pressure wave charger 2. The measurement of the oxygen content is therefore carried out under constant pressure conditions. In the case of an internal combustion engine charged with a pressure wave supercharger 2, the person skilled in the art would not measure the oxygen concentration in the low-pressure exhaust gas 444 because this is mixed with purge air and the measured ⁇ therefore does not match the actual excess air number in the high-pressure exhaust gas 333.
  • the lambda probe 7 in the full flow of the low-pressure exhaust gas 444 therefore only functions properly if the purge degree of the pressure wave charger 2 ⁇ sp ⁇ 0 or if the exhaust gas recirculation Rz> 0.
  • the oxygen content measured by the lambda probe 7 in the full flow of the low-pressure exhaust gas 444 which comes about, for example, on the basis of the diffusion of the oxygen through a solid electrolyte, creates a measurement signal 9 for the Computer unit 8:
  • the corresponding control information then acts on the throttle valve 4 and / or the start valve 6. If a circuit does not have any filtering of the exhaust gases, the lambda probe 7 is used to reduce the NO x values.
  • the influence of the temperature fluctuations of the exhaust gas on the measurement signal 9 of the lambda probe 7 can also be reduced with particular advantage.
  • FIG. 2 it is shown as a development of a cylindrical section halfway up the cells through the rotor and through the adjoining parts of the side parts of the housing.
  • FIG. 2 it is shown as a single-cycle machine, which is expressed in that the gas housing 22 and the air housing 23 are provided on their sides facing the rotor 21 with only one high-pressure and one low-pressure opening.
  • the flow directions of the working media and the direction of rotation of the pressure wave machine are indicated by arrows.
  • the hot exhaust gases of the internal combustion engine enter through the high-pressure gas inflow channel 24 into the rotor 21, which is provided with axially straight cells 25 that are open on both sides, expand therein and leave it via the low-pressure gas outflow channel 26 into the exhaust, not shown.
  • Atmospheric fresh air is drawn in on the air side, flows axially into the rotor 21 via the low-pressure air inlet duct 27, is compressed therein and leaves it as charge air via the high-pressure air outlet duct 28 via a charge air cooler (not shown) to the engine.
  • the cell band consisting of the cells 25 is the development of a cylindrical section of the rotor 21, which moves to the right when the latter rotates in the direction of the arrow.
  • the pressure wave processes take place inside the rotor 21 and essentially cause a gas-filled space and an air-filled space to form.
  • the exhaust gas relaxes and then escapes into the low-pressure gas outflow duct 26, while in the second part of the fresh air drawn in is compressed and pushed out into the high-pressure air outlet duct 28.
  • the proportion of scavenging air falsifies the measurement, depending on the position of the lambda probe, in that a value that is larger than the real ⁇ would be measured. This would be e.g. the case when the probe would be in the area of the closing edge 31 of the low-pressure gas outflow channel 26.
  • the lambda probe 7 is therefore advantageously arranged in the region of the opening edge 32 of the low-pressure gas outflow channel 26, that is to say where there is a pure exhaust gas flow under all conditions.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Exhaust Gas After Treatment (AREA)
  • Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
  • Supercharger (AREA)
  • Testing Of Engines (AREA)
  • Measuring Fluid Pressure (AREA)

Abstract

In an internal combustion engine supercharged by a pressure-wave supercharger (2), a lambda probe (7) is used for measurement of the oxygen content in the circuit. The oxygen content determined by the lambda probe (7) creates a measuring signal (9), which is used for controlling the throttle valve (4) and/or the starting valve (6). This control is aimed at reducing the NOx emissions from the combustion and possibly ensuring the regeneration of an exhaust gas particle filter (3) integrated in the circuit. In this arrangement, the lambda probe (7) is to be placed in the low-pressure exhaust gas line (444), which has a positive effect on the response capability and the accuracy of the measured data of the probe (7). This obviates the need for additional aids for the correction of pressure fluctuations such as occur at other points in the circuit of the internal combustion engine.

Description

Die vorliegende Erfindung betrifft die Schaltung einer mit einem Druckwellenlader aufgeladenen Brennkraftmaschine gemäss Oberbegriff des Anspruchs 1.The present invention relates to the circuitry of an internal combustion engine charged with a pressure wave supercharger according to the preamble of claim 1.

Zur Verbesserung des Abgasverhaltens von Brennkraftmaschi­nen sieht man zunehmend den Einbau von Abgaspartikel­filtern vor. Vordringliche Aufgabe dieser Filter ist es, die für die Umwelt schädigenden Russpartikeln einzu­fangen. Neueste Vorschläge gehen dahin, die Filterungs­kanäle dieser Abgaspartikelfilter katalytisch zu be­schichten, wodurch weitere Schadstoffe aus der Verbren­nung neutralisiert werden können. Es ist offensichtlich, dass die eingefangenen Russpartikeln mit der Zeit unweiger­lich den Filter verstopfen werden: Der Strömungswiderstand des Abgasstromes steigt dannzumal extrem an, was sich auf den Wirkungsgrad der Brennkraftmaschine negativ auswirkt. Massnahmen hiergegen verfolgen das Ziel, durch dauernde oder kurzzeitige Erhöhung der Filtertemperatur die Russbelegung durch Verbrennung zu beseitigen.In order to improve the exhaust gas behavior of internal combustion engines, the installation of exhaust gas particle filters is increasingly envisaged. The primary task of these filters is to capture the soot particles that are harmful to the environment. The latest proposals are to catalytically coat the filtering channels of these exhaust gas particle filters, as a result of which further pollutants from the combustion can be neutralized. It is obvious that the trapped soot particles will inevitably clog the filter over time: the flow resistance of the exhaust gas flow then increases extremely, which has a negative effect on the efficiency of the internal combustion engine. Measures against this aim to remove the soot build-up by combustion by increasing the filter temperature for a short period of time.

Damit aber diese Verbrennung auch stattfinden kann, muss sichergestellt werden, dass die Abgase während der Verbrennung der Russbelegung im Filter genügend Sauerstoff heranführen.But for this combustion to take place, it must be ensured that the exhaust gases bring enough oxygen into the filter during the combustion of the soot coating.

Grundsätzlich geht es also immer darum, einerseits zur Erhöhung der Abgastemperatur und somit der Filtertempera­tur zwecks Regenerierung des Abgaspartikelfilters Abgas in die Verbrennungsluft des Motors rezirkulieren zu lassen, und andererseits die minimal erforderliche bzw. die optimal gewünschte Sauerstoffalimentation zu gewähr­leisten.Basically, it is always a question of, on the one hand, to increase the exhaust gas temperature and thus the filter temperature for the regeneration of the exhaust gas particle filter to recirculate exhaust gas into the combustion air of the engine, and on the other hand to ensure the minimum required or the optimally desired oxygen concentration.

Zur Regelung des Sauerstoffgehaltes bei der Regenerierung des Abgaspartikelfilters, und infolgedessen zur Steuerung der Drosselklappe, wird zwischen Motor und Abgaspartikel­filter als Sauerstoffsensor eine "Lambda-Sonde" eingebaut, deren Messignal einem Regelsystem der Brennkraftmaschine zugeführt wird, das in geeigneter Weise auf die Frischluft­zufuhr und/oder die Treibstoffmenge einwirkt.To regulate the oxygen content during regeneration of the exhaust gas particle filter, and consequently to control the throttle valve, a "lambda probe" is installed between the engine and the exhaust gas particle filter as an oxygen sensor, the measurement signal of which is fed to a control system of the internal combustion engine, which is suitably adapted to the fresh air supply and / or the amount of fuel.

Eine zur Messung des Sauerstoffgehaltes im Abgas von Brennkraftmaschinen relativ zum Sauerstoffgehalt der Luft geeignete "Lambda-Sonde" mit einer ZRO₂-Keramik ist beispielsweise aus dem Artikel von Hans-Martin Wieden­mann et al., "Heated Zirconia Oxygen Sensor for Stoichiome­tric and Lean Air-Fuel Ratios", SAE-Paper 840141, SAE-­Congres, Detroit, Febr.-März 1984, bekannt geworden.A "lambda probe" with a ZRO₂ ceramic suitable for measuring the oxygen content in the exhaust gas of internal combustion engines relative to the oxygen content of the air is, for example, from the article by Hans-Martin Wiedenmann et al., "Heated Zirconia Oxygen Sensor for Stoichiometric and Lean Air- Fuel Ratios ", SAE Paper 840141, SAE Congres, Detroit, February-March 1984.

Grundsätzlich ist zu sagen, dass der Sauerstoff-Partial­druck im Abgas sich jedoch mit dem Abgasdruck ändert. Nun ist der Druck des Abgases im Abgassystem einer Brenn­kraftmaschine keineswegs konstant, sondern hängt stark vom Grad der Verstopfung des Abgaspartikelfilters und der Motordrehzahl ab. Bei aufgeladenen Brennkraftmaschi­nen sind die Druckschwankungen im Abgassystem noch viel grösser, da sich zu den genannten Einflüssen Motordrehzahl und Verstopfungsgrad des Abgaspartikelfilters noch der jeweilige Aufladegrad addiert.Basically, it can be said that the oxygen partial pressure in the exhaust gas changes with the exhaust gas pressure. Now, the pressure of the exhaust gas in the exhaust system of an internal combustion engine is by no means constant, but depends strongly on the degree of clogging of the exhaust gas particle filter and the engine speed. With supercharged internal combustion engines, the pressure fluctuations in the exhaust system are still a lot greater, since the respective engine charge and the degree of clogging of the exhaust gas particle filter are added to the influences mentioned.

Bezüglich einer Schaltung einer aufgeladenen Brennkraft­maschine bedeutet dies, dass wenn die Lambda-Sonde im Hochdruck-Abgasstrom eingebaut ist, der dort herrschende Druck sich als unzulässige Störgrösse erweist, weil das Ausgangssignal der Lambda-Sonde druckabhängig ist: Insgesamt kann der Druck des Abgases im Abgassystem um ein Mehrfaches des Luftdruckes schwanken. Es versteht sich von selbst, dass unter solchen Bedingungen die Messung des prozentualen Sauerstoffgehaltes im Abgas mittels der bekannten, direkt in eine Wand des Abgas­systems eingeschraubten Lambda-Sonde keine brauchbaren Ergebnisse liefert. Will man hiergegen Abhilfe schaffen, so erfordert dies eine Druckkorrektur oder den Einbau der Lambda-Sonde in einem Bypass-Teilstrom des Abgassystems, die letztgenannte Abhilfe vorzugsweise vor dem Abgaspar­tikelfilter, wenn die Schaltung mit einem solchen versehen ist.With regard to a circuit of a turbocharged internal combustion engine, this means that if the lambda probe is installed in the high-pressure exhaust gas flow, the pressure prevailing there proves to be an impermissible disturbance variable because the output signal of the lambda probe is pressure-dependent: overall, the pressure of the exhaust gas in the exhaust system can fluctuate by a multiple of the air pressure. It goes without saying that under such conditions, the measurement of the percentage oxygen content in the exhaust gas by means of the known lambda probe screwed directly into a wall of the exhaust system does not provide any useful results. If this is to be remedied, this requires a pressure correction or the installation of the lambda probe in a bypass partial flow of the exhaust system, the latter remedy preferably upstream of the exhaust gas particle filter if the circuit is provided with one.

Indessen, die Druckkorrektur, welche den Einfluss des Abgasdruckes auf das Messignal der Lambda-Sonde eliminie­ren könnte, setzt die Verwendung eines Drucksensors und einer elektronischen Rechnereinheit voraus. Dies ist jedoch eine aufwendige Lösung, da der Drucksensor im Abgassystem extrem korrosionsbeständig sein muss.However, the pressure correction, which could eliminate the influence of the exhaust gas pressure on the measurement signal of the lambda probe, requires the use of a pressure sensor and an electronic computer unit. However, this is a complex solution because the pressure sensor in the exhaust system must be extremely corrosion-resistant.

Auch die andere Vorkehrung, nämlich der Einbau der Lambda-­Sonde in einem Bypass-Teilstrom im Abgassystem, erweist sich als aufwendige Lösung, sei es im schaltungsgerech­ten Einbau der Hilfsmassnahme als auch bezüglich der eingesetzten Mittel.The other precaution, namely the installation of the lambda sensor in a bypass partial flow in the exhaust system, also proves to be a complex solution, be it in the circuit-appropriate installation of the auxiliary measure or in terms of the means used.

Die Erfindung, wie sie im Anspruch 1 gekennzeichnet ist, löst die Aufgabe, den direkten Einbau der Lambda-­Sonde an einem Ort der Schaltung vorzusehen, wo der zu messende Sauerstoffgehalt unmittelbar informations­echt vorliegt.The invention, as characterized in claim 1, solves the problem of providing for the direct installation of the lambda probe at a location of the circuit where the oxygen content to be measured is immediately available in an information-correct manner.

Die Vorteile der erfindungsgemässen Plazierung der Lambda­Sonde sind im wesentlichen darin zu sehen, dass im Voll­strom der Niederdruckabgase eine schnellere Ansprechzeit der Lamda-Sonde erreicht wird, weil dort mehr Menge als in einem Bypass-Teilstrom strömt. Auch kann bei Messungen im Vollstrom der Niederdruckabgase auf eine Druckkorrektur verzichtet werden, weil dort keine Druck­schwankungen vorhanden sind.The advantages of the placement of the lambda probe according to the invention can essentially be seen in the fact that a faster response time of the lambda probe is achieved in the full flow of the low-pressure exhaust gases, because there flows more volume than in a bypass partial flow. A pressure correction can also be dispensed with when measuring in full flow of the low-pressure exhaust gases because there are no pressure fluctuations.

Im folgenden wird anhand der Zeichnung ein Ausführungs­beispiel der Erfindung erläutert. Alle für das unmittel­bare Verständnis der Erfindung nicht erforderlichen Elemente sind fortgelassen.In the following an embodiment of the invention will be explained with reference to the drawing. All elements not necessary for the immediate understanding of the invention have been omitted.

Es zeigen:

  • Fig. 1 die Schaltung einer mit einem Druckwellenlader aufgeladenen Brennkraftmaschine mit eingebauter Lambda-Sonde,
  • Fig. 2 die Anordnung der Lambda-Sonde im Druckwellenlader.
Show it:
  • 1 shows the circuit of an internal combustion engine charged with a pressure wave charger with a built-in lambda probe,
  • Fig. 2 shows the arrangement of the lambda probe in the pressure wave charger.

Die in Figur 1 gezeigte Schaltung besteht aus einem Motor 1, einem Druckwellenlader 2, einem Abgaspartikel­filter 3. In der Luftansaugleitung 111 zum Druckwellen­lader ist eine Drosselklappe 4 plaziert, welche von einem Stellmotor 5 verstellt wird. In der Leitung für die Frischluftzufuhr 222 zum Motor 1 ist ein Startventil bzw. eine Ladeluftklappenautomatik 6 plaziert. Der Abgas­partikelfilter 3 ist in der Hochdruckabgasleitung 333 eingebaut, also zwischen Motor 1 und Druckwellenlader 2. In der Niederdruckabgasleitung 444 wirkt eine Lambda-­Sonde 7, deren Anordnung getrennt von einem möglichen Spülstrom, vorzugsweise im Oeffnungsbereich des Nieder­druckgas-Abströmkanals 26 (Fig. 2) vorgesehen ist. Die Lambda-Sonde 7 ermittelt den Sauerstoffgehalt im Abgas, nachdem dieses im Druckwellenlader 2 Aufladungsarbeit verrichtet hat. Die Messung des Sauerstoffgehaltes ge­schieht daher unter gleichbleibenden Druckverhältnissen. Im Falle einer mit einem Druckwellenlader 2 aufgeladenen Brennkraftmaschine würde der Fachmann die Sauerstoffkonzen­tration nicht im Niederdruckabgas 444 messen, weil dieses mit Spülluft vermischt ist und das gemessene λ deshalb nicht mit der wirklichen Luftüberschusszahl im Hochdruck­abgas 333 übereinstimmt. Die Lambda-Sonde 7 im Vollstrom des Niederdruckabgases 444 funktioniert demnach nur dann richtig, wenn der Spülgrad des Druckwellenladers 2 η sp ≦ 0 bzw., wenn die Abgasrezirkulation Rz > 0 ist. Nun ist im normalen Betriebsbereich eines Druckwellen­laders 2, trotz der Spülfunktion in der Niederdruckzone, der Einbau der Lambda-Sonde 7 im Vollstrom des Nieder­druckabgases 444 möglich, denn im Regelbereich der Drossel­klappe 4 ist η sp immer kleiner als Null, bzw. die Rezirku­lation immer grösser als Null. Die verblüffende Möglich­keit, in einer Schaltung einer mit einem Druckwellen­lader 2 aufgeladenen Brennkraftmaschine die Lambda-Sonde 7 im Vollstrom des Niederdruckabgases 444 plazieren zu können, setzt demgemäss also voraus, dass das Abgas nicht mit zusätzlicher Spülluft vermischt wird, d.h., dass die Sauerstoffkonzentration des Motorabgases nicht verfälscht wird. Dies ist wie gesagt, innerhalb des Regelbereichs der Drosselklappe 4, stets der Fall. Der von der Lambda-­Sonde 7 im Vollstrom des Niederdruckabgases 444 gemessene Sauerstoffgehalt, welcher beispielsweise anhand der Diffusion des Sauerstoffes durch einen Festkörperelektro­lyten zustande kommt, schafft ein Messignal 9 für die Rechnereinheit 8: Die entsprechenden Regelinformationen wirken dann auf die Drosselklappe 4 und/oder das Start­ventil 6. Weist eine Schaltung keine Filterung der Abgase auf, so wird die Lambda-Sonde 7 zur Verminderung der NOX-Werte herangezogen. Durch die Verwendung eines schlecht wärmeleitenden Materials bei der Verbindung der Lambda-­Sonde 7 mit dem Abgassystem lässt sich mit besonderem Vorteil zusätzlich noch der Einfluss der Temperatur­schwankungen des Abgases auf das Messignal 9 der Lambda-­Sonde 7 reduzieren.The circuit shown in FIG. 1 consists of a motor 1, a pressure wave charger 2, an exhaust gas particle filter 3. A throttle valve 4, which is adjusted by a servomotor 5, is placed in the air intake line 111 to the pressure wave charger. A start valve or an automatic charge air flap 6 is placed in the line for the fresh air supply 222 to the engine 1. The exhaust gas particle filter 3 is in the high-pressure exhaust gas line 333 installed, ie between engine 1 and pressure wave charger 2. A lambda probe 7 acts in the low-pressure exhaust gas line 444, the arrangement of which is provided separately from a possible purge flow, preferably in the opening area of the low-pressure gas outflow channel 26 (FIG. 2). The lambda probe 7 determines the oxygen content in the exhaust gas after it has performed charging work in the pressure wave charger 2. The measurement of the oxygen content is therefore carried out under constant pressure conditions. In the case of an internal combustion engine charged with a pressure wave supercharger 2, the person skilled in the art would not measure the oxygen concentration in the low-pressure exhaust gas 444 because this is mixed with purge air and the measured λ therefore does not match the actual excess air number in the high-pressure exhaust gas 333. The lambda probe 7 in the full flow of the low-pressure exhaust gas 444 therefore only functions properly if the purge degree of the pressure wave charger 2 η sp ≦ 0 or if the exhaust gas recirculation Rz> 0. Now, in the normal operating range of a pressure wave charger 2, despite the flushing function in the low-pressure zone, it is possible to install the lambda probe 7 in the full flow of the low-pressure exhaust gas 444, because in the control range of the throttle valve 4, η sp is always less than zero, or the recirculation is always greater as zero. The astonishing possibility of being able to place the lambda probe 7 in the full flow of the low-pressure exhaust gas 444 in a circuit of an internal combustion engine charged with a pressure wave charger 2 therefore presupposes that the exhaust gas is not mixed with additional purge air, that is, that the oxygen concentration of the engine exhaust gas is not falsified. As stated, this is always the case within the control range of the throttle valve 4. The oxygen content measured by the lambda probe 7 in the full flow of the low-pressure exhaust gas 444, which comes about, for example, on the basis of the diffusion of the oxygen through a solid electrolyte, creates a measurement signal 9 for the Computer unit 8: The corresponding control information then acts on the throttle valve 4 and / or the start valve 6. If a circuit does not have any filtering of the exhaust gases, the lambda probe 7 is used to reduce the NO x values. By using a poorly heat-conducting material when connecting the lambda probe 7 to the exhaust system, the influence of the temperature fluctuations of the exhaust gas on the measurement signal 9 of the lambda probe 7 can also be reduced with particular advantage.

Dies ist vor allem bei Brennkraftmaschinen, die mit einem hohen Sauerstoffgehalt im Abgas gefahren werden, insbesondere bei Dieselmotoren, von ganz erheblicher Bedeutung.This is of very great importance especially in internal combustion engines which are operated with a high oxygen content in the exhaust gas, in particular in diesel engines.

In Fig. 2 ist eine vorteilhafte Einbauvariante innerhalb der gasdynamischen Druckwellenmaschinen gezeigt.2 shows an advantageous installation variant within the gas-dynamic pressure wave machines.

Der grundsätzliche Aufbau einer solchen Druckwellenma­schine und deren genaue Struktur kann der Druckschrift CH-T 123 143 der Anmelderin oder der CH-PS 378 595 entnommen werden. In der Figur 2 ist sie als Abwicklung eines Zylinderschnittes in halber Höhe der Zellen durch den Rotor und durch die daran anschliessenden Partien der Seitenteile des Gehäuses gezeigt. Der Einfachheit halber ist sie als Einzyklus-Maschine dargestellt, was sich dadurch ausdrückt, dass das Gasgehäuse 22 und das Luftge­häuse 23 an ihren dem Rotor 21 zugekehrten Seiten mit nur je einer Hochdruck- und einer Niederdrucköffnung versehen sind. Um die Funktion des Systems übersichtlicher zu erläutern, sind die Strömungsrichtungen der Arbeits­medien und die Drehrichtung der Druckwellenmaschine mit Pfeilen bezeichnet.The basic structure of such a pressure wave machine and its exact structure can be found in the document CH-T 123 143 by the applicant or CH-PS 378 595. In FIG. 2 it is shown as a development of a cylindrical section halfway up the cells through the rotor and through the adjoining parts of the side parts of the housing. For the sake of simplicity, it is shown as a single-cycle machine, which is expressed in that the gas housing 22 and the air housing 23 are provided on their sides facing the rotor 21 with only one high-pressure and one low-pressure opening. In order to explain the function of the system more clearly, the flow directions of the working media and the direction of rotation of the pressure wave machine are indicated by arrows.

Die heissen Abgase des hier nicht gezeigten Verbrennungs­motors treten durch den Hochdruckgas-Zuströmkanal 24 in den mit axialgeraden, beidseitig offenen Zellen 25 versehenen Rotor 21 ein, expandieren darin und verlassen ihn über den Niederdruckgas-Abströmkanal 26 in den nicht gezeigten Auspuff. Auf der Luftseite wird atmosphärische Frischluft angesaugt, strömt über den Niederdruckluft-Ein­trittskanal 27 axial in den Rotor 21 ein, wird darin verdichtet und verlässt ihn als Ladeluft über den Hoch­druckluft-Austrittskanal 28 über einen nicht gezeigten Ladeluftkühler zum Motor hin.The hot exhaust gases of the internal combustion engine, not shown here, enter through the high-pressure gas inflow channel 24 into the rotor 21, which is provided with axially straight cells 25 that are open on both sides, expand therein and leave it via the low-pressure gas outflow channel 26 into the exhaust, not shown. Atmospheric fresh air is drawn in on the air side, flows axially into the rotor 21 via the low-pressure air inlet duct 27, is compressed therein and leaves it as charge air via the high-pressure air outlet duct 28 via a charge air cooler (not shown) to the engine.

Zum Verständnis des eigentlichen, äusserst komplexen gasdynamischen Druckwellenprozesses, welcher nicht Er­findungsgegenstand ist, wird auf die schon genannte Druckschrift CH-T 123 143 verwiesen. Der für das Verständ­nis der Erfindung notwendige Prozessablauf wird nachste­hend kurz erläutert: Das aus den Zellen 25 bestehende Zellenband ist die Abwicklung eines Zylinderschnittes des Rotors 21, welche sich bei Drehung des letzteren in Pfeilrichtung nach rechts bewegt. Die Druckwellenvor­gänge laufen im Innern des Rotors 21 ab und bewirken im wesentlichen, dass sich ein gasgefüllter Raum und ein luftgefüllter Raum bilden. Im ersteren entspannt sich das Abgas und entweicht dann in den Niederdruckgas-­Abströmkanal 26, während im zweiten ein Teil der angesaug­ten Frischluft verdichtet und in den Hochdruckluft-Aus­trittskanal 28 ausgeschoben wird. Der verbleibende Frisch­luftanteil wird durch den Rotor in den Niederdruckgas-­Abströmkanal 26 überspült und bewirkt damit den voll­ständigen Austritt der Abgase. Diese Spülung ist für den Prozessablauf wesentlich und muss unter allen Umstän­den aufrechterhalten bleiben. Es soll auf jeden Fall vermieden werden, dass Abgas im Rotor 21 verbleibt und bei einem nachfolgenden Zyklus mit der Ladeluft dem Motor zugeführt wird.To understand the actual, extremely complex gas dynamic pressure wave process, which is not the subject of the invention, reference is made to the already mentioned document CH-T 123 143. The process sequence necessary for understanding the invention is briefly explained below: The cell band consisting of the cells 25 is the development of a cylindrical section of the rotor 21, which moves to the right when the latter rotates in the direction of the arrow. The pressure wave processes take place inside the rotor 21 and essentially cause a gas-filled space and an air-filled space to form. In the former, the exhaust gas relaxes and then escapes into the low-pressure gas outflow duct 26, while in the second part of the fresh air drawn in is compressed and pushed out into the high-pressure air outlet duct 28. The remaining fresh air portion is flushed through the rotor into the low-pressure gas outflow channel 26 and thus causes the exhaust gases to exit completely. This rinsing is essential for the process flow and must be maintained under all circumstances. In any case, it should be avoided that exhaust gas remains in the rotor 21 and is supplied to the engine with the charge air in a subsequent cycle.

Je nach Maschinenauslegung und Betriebsbedingungen findet ein Rezirkulieren einer bestimmten Abgasmenge statt; aus Umweltschutzgründen ist dies sogar erwünscht. Dies wird dadurch erreicht, dass ein gewisser Gasanteil auf die Luftseite hinübertritt und im Bereich der Schliess­kante 29 in den Hochdruck-Austrittskanal 28 überspült wird. Dieser Sachverhalt ist in der Prinzipskizze durch die Trennfront 30 zwischen Luft und Gas dargestellt. Diese Trennfront ist nicht eine scharfe Begrenzung, sondern vielmehr eine relativ breite Mischzone. Die solchermassen mt Abgas belastete Ladeluft bewirkt er­wünschte Erhöhung der Abgastemperatur.Depending on the machine design and operating conditions, a certain amount of exhaust gas is recirculated; this is even desirable for environmental reasons. This is achieved in that a certain proportion of gas passes over to the air side and is flushed into the high-pressure outlet channel 28 in the area of the closing edge 29. This fact is shown in the schematic diagram by the separating front 30 between air and gas. This dividing front is not a sharp boundary, but rather a relatively wide mixing zone. The charge air loaded with exhaust gas in this way causes a desired increase in the exhaust gas temperature.

Wie bereits anlässlich der Beschreibung der Fig. 1 erwähnt, verfälscht der Anteil Spülluft je nach Lage der Lambda-­Sonde die Messung insofern, als ein gegenüber dem Echt-λ grösserer Wert gemessen würde. Dies wäre dann z.B. der Fall, wenn sich die Sonde im Bereich der Schliesskante 31 des Niederdruckgas-Abströmkanals 26 befinden würde. Mit Vorteil wird deshalb die Lambda-Sonde 7 im Bereich der Oeffnungskante 32 des Niederdruckgas-Abströmkanals 26 angeordnet, dort also, wo bei allen Bedingungen eine reine Abgasströmung vorherrscht.As already mentioned on the occasion of the description of FIG. 1, the proportion of scavenging air falsifies the measurement, depending on the position of the lambda probe, in that a value that is larger than the real λ would be measured. This would be e.g. the case when the probe would be in the area of the closing edge 31 of the low-pressure gas outflow channel 26. The lambda probe 7 is therefore advantageously arranged in the region of the opening edge 32 of the low-pressure gas outflow channel 26, that is to say where there is a pure exhaust gas flow under all conditions.

Claims (3)

1. Schaltung einer mit einem Druckwellenlader aufgeladenen Brennkraftmaschine, im wesentlichen bestehend aus einem Motor (1), einem Druckwellenlader (2), einem Abgaspartikelfilter (3), einer Drosselklappe (4) und einem Startventil (6), dadurch gekennzeichnet, dass in der Niederdruckabgasleitung (444) eine Lambda-­Sonde (7) eingebaut ist, deren Messignal (9) über eine Rechnereinheit (8) auf die Drosselklappe (4) und/oder das Startventil (6) einwirkt.1. Circuit of an internal combustion engine charged with a pressure wave supercharger, consisting essentially of an engine (1), a pressure wave supercharger (2), an exhaust gas particle filter (3), a throttle valve (4) and a start valve (6), characterized in that in the Low-pressure exhaust gas line (444) a lambda probe (7) is installed, the measurement signal (9) of which acts on the throttle valve (4) and / or the start valve (6) via a computer unit (8). 2. Schaltung nach Anspruch 1, dadurch gekennzeichnet, dass die Lambda-Sonde (7) im Vollstrom der durch die Niederdruckabgasleitung (444) strömenden Abgase misst.2. Circuit according to claim 1, characterized in that the lambda probe (7) measures in full flow of the exhaust gases flowing through the low-pressure exhaust gas line (444). 3. Schaltung nach Anspruch 2, dadurch gekennzeichnet, dass die Lambda-Sonde (7) im Oeffnungsbereich des Niederdruckgas-Abströmkanals (26) angeordnet ist.3. Circuit according to claim 2, characterized in that the lambda probe (7) is arranged in the opening region of the low-pressure gas outflow channel (26).
EP87108266A 1986-07-08 1987-06-08 Internal combustion engine with pressure wave charging and a lambda probe Expired - Lifetime EP0252316B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT87108266T ATE59432T1 (en) 1986-07-08 1987-06-08 COMBUSTION ENGINE WITH PRESSURE WAVE CHARGER AND LAMDA PROBE.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CH2749/86 1986-07-08
CH274986 1986-07-08

Publications (2)

Publication Number Publication Date
EP0252316A1 true EP0252316A1 (en) 1988-01-13
EP0252316B1 EP0252316B1 (en) 1990-12-27

Family

ID=4240740

Family Applications (1)

Application Number Title Priority Date Filing Date
EP87108266A Expired - Lifetime EP0252316B1 (en) 1986-07-08 1987-06-08 Internal combustion engine with pressure wave charging and a lambda probe

Country Status (5)

Country Link
US (1) US4798049A (en)
EP (1) EP0252316B1 (en)
JP (1) JPS6325318A (en)
AT (1) ATE59432T1 (en)
DE (1) DE3767056D1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3907939A1 (en) * 1989-01-27 1990-08-02 Asea Brown Boveri Device for cleaning the exhaust gases from diesel engines
DE102011003095A1 (en) * 2011-01-25 2012-07-26 Ford Global Technologies, Llc Method for determining the oxygen concentration O 2 in a gas flow and oxygen sensor for carrying out the method

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5199257A (en) * 1989-02-10 1993-04-06 Centro Sviluppo Materiali S.P.A. Device for removal of particulates from exhaust and flue gases
JP2549913B2 (en) * 1989-04-19 1996-10-30 富士写真フイルム株式会社 Radiation image conversion panel
DE3928666A1 (en) * 1989-08-30 1991-03-07 Asea Brown Boveri SWITCHING OF AN INTERNAL COMBUSTION ENGINE
US5048470A (en) * 1990-12-24 1991-09-17 Ford Motor Company Electronically tuned intake manifold
US6055965A (en) * 1997-07-08 2000-05-02 Caterpillar Inc. Control system for exhaust gas recirculation system in an internal combustion engine
US8025199B2 (en) * 2004-02-23 2011-09-27 Tyco Healthcare Group Lp Surgical cutting and stapling device
US6589314B1 (en) 2001-12-06 2003-07-08 Midwest Research Institute Method and apparatus for agglomeration
WO2006126922A1 (en) * 2005-05-26 2006-11-30 Volvo Lastvagnar Ab Method for regeneration of an exhaust aftertreatment system
DE102006020522A1 (en) * 2006-05-03 2007-11-08 Robert Bosch Gmbh Method for operating an IC engine with pressure pulse supercharger to drive air into engine in relation to actual engine parameters
DE102010049361A1 (en) * 2010-10-26 2012-04-26 Benteler Automobiltechnik Gmbh Pressure wave supercharger arrangement for internal combustion engine of e.g. motor car, has channel separated by separator into channel for removal of exhaust gas and another channel formed as rinsing channel for fresh air

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2354313A1 (en) * 1972-11-01 1974-05-09 Hitachi Ltd MIXING RATIO CONTROL DEVICE FOR COMBUSTION MACHINERY
EP0152870A2 (en) * 1984-02-21 1985-08-28 Comprex Ag Regeneration method for the exhaust filter of a combustion engine
DE3526532A1 (en) * 1984-07-24 1986-02-13 Mazda Motor Corp., Hiroshima INLET TRAINING FOR INTERNAL COMBUSTION ENGINE WITH CHARGER

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS55165432A (en) * 1979-06-12 1980-12-23 Sharp Corp Cooker
JPS6035546B2 (en) * 1979-07-02 1985-08-15 トヨタ自動車株式会社 Air-fuel ratio control device for internal combustion engine with exhaust turbocharger
JPS5681235A (en) * 1979-12-04 1981-07-03 Nippon Soken Inc Air-fuel ratio controller for internal combustion engine with supercharger
DE3270986D1 (en) * 1981-08-11 1986-06-12 Bbc Brown Boveri & Cie Supercharged internal-combustion engine with a filter for exhaust gas particles
CH665002A5 (en) * 1984-11-09 1988-04-15 Bbc Brown Boveri & Cie METHOD AND DEVICE FOR OPERATING A DIESEL ENGINE WITH AN EXHAUST GAS FILTERING DEVICE.

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2354313A1 (en) * 1972-11-01 1974-05-09 Hitachi Ltd MIXING RATIO CONTROL DEVICE FOR COMBUSTION MACHINERY
EP0152870A2 (en) * 1984-02-21 1985-08-28 Comprex Ag Regeneration method for the exhaust filter of a combustion engine
DE3526532A1 (en) * 1984-07-24 1986-02-13 Mazda Motor Corp., Hiroshima INLET TRAINING FOR INTERNAL COMBUSTION ENGINE WITH CHARGER

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3907939A1 (en) * 1989-01-27 1990-08-02 Asea Brown Boveri Device for cleaning the exhaust gases from diesel engines
DE102011003095A1 (en) * 2011-01-25 2012-07-26 Ford Global Technologies, Llc Method for determining the oxygen concentration O 2 in a gas flow and oxygen sensor for carrying out the method

Also Published As

Publication number Publication date
EP0252316B1 (en) 1990-12-27
ATE59432T1 (en) 1991-01-15
DE3767056D1 (en) 1991-02-07
US4798049A (en) 1989-01-17
JPS6325318A (en) 1988-02-02

Similar Documents

Publication Publication Date Title
EP0896139B1 (en) Method for operating a combustion engine
DE19914787C2 (en) Emission control system for an internal combustion engine
DE10316062B4 (en) A system for estimating a NOx content of the exhaust gas generated by an internal combustion engine
EP0252316B1 (en) Internal combustion engine with pressure wave charging and a lambda probe
DE102005008650A1 (en) Internal combustion engine with an exhaust gas turbocharger and an exhaust gas recirculation device
DE112005000486T5 (en) Control device for charging device with electric motor
DE102011003095A1 (en) Method for determining the oxygen concentration O 2 in a gas flow and oxygen sensor for carrying out the method
DE102005008651A1 (en) Internal combustion engine with an exhaust gas turbocharger and an exhaust gas recirculation device
DE2315634C3 (en) Process for reducing pollutant emissions from internal combustion engines and device for carrying out the process
DE102010037650B4 (en) O2 control system for an internal combustion engine and method for controlling the O2 concentration
DE3203952A1 (en) INTERNAL COMBUSTION ENGINE WITH CHARGING
EP2154355B1 (en) Charged internal combustion engine with exhaust gas recirculation
DE102008026706A1 (en) An exhaust purification control device and control method for an internal combustion engine
DE102011089847B4 (en) Engine control device
DE10241884B4 (en) Method for operating an internal combustion engine
DE60131161T2 (en) METHOD AND DEVICE FOR EXHAUST RECOVERY AND A CHARGED DIESEL ENGINE
DE4235794C1 (en) Exhaust gas feedback for IC engine - has feedback conduit connecting exhaust gas conduit before turbine with charging air conduit after compressor
DE102004044893A1 (en) Exhaust gas recirculation device and method for operating an exhaust gas recirculation device
DE3634163A1 (en) EXHAUST GAS RECIRCULATION SYSTEM FOR AN INTERNAL COMBUSTION ENGINE
EP1705354A1 (en) Method for controlling an internal combustion engine
EP1861603A1 (en) Method for controlling the combustible air/fuel mixture located inside the combustion chamber of an internal combustion engine
DE3909544C2 (en)
DE10233362A1 (en) Device for determining the exhaust gas recirculation rate of an internal combustion engine
DE19623970C2 (en) Supercharged internal combustion engine with an exhaust gas recirculation line
DE102018101425A1 (en) EGR control device

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT CH DE FR GB IT LI

17P Request for examination filed

Effective date: 19880701

17Q First examination report despatched

Effective date: 19890914

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: COMPREX AG

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT CH DE FR GB IT LI

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

Effective date: 19901227

Ref country code: GB

Effective date: 19901227

Ref country code: FR

Effective date: 19901227

REF Corresponds to:

Ref document number: 59432

Country of ref document: AT

Date of ref document: 19910115

Kind code of ref document: T

REF Corresponds to:

Ref document number: 3767056

Country of ref document: DE

Date of ref document: 19910207

EN Fr: translation not filed
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: AT

Effective date: 19910608

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: CH

Effective date: 19910630

Ref country code: LI

Effective date: 19910630

GBV Gb: ep patent (uk) treated as always having been void in accordance with gb section 77(7)/1977 [no translation filed]
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19960614

Year of fee payment: 10

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19980401