EP0081759A2 - Apparatus for regulating the air-fuel ratio in an internal-combustion engine - Google Patents

Apparatus for regulating the air-fuel ratio in an internal-combustion engine Download PDF

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Publication number
EP0081759A2
EP0081759A2 EP82111154A EP82111154A EP0081759A2 EP 0081759 A2 EP0081759 A2 EP 0081759A2 EP 82111154 A EP82111154 A EP 82111154A EP 82111154 A EP82111154 A EP 82111154A EP 0081759 A2 EP0081759 A2 EP 0081759A2
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EP
European Patent Office
Prior art keywords
probe
voltage
resistance
lambda
switch
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Granted
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EP82111154A
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German (de)
French (fr)
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EP0081759A3 (en
EP0081759B1 (en
Inventor
Werner Dipl.-Ing. Jundt
Rolf Dipl.-Ing. Reischl
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Robert Bosch GmbH
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Robert Bosch GmbH
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/02—Circuit arrangements for generating control signals
    • F02D41/14—Introducing closed-loop corrections
    • F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
    • F02D41/1477—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the regulation circuit or part of it,(e.g. comparator, PI regulator, output)
    • F02D41/1479—Using a comparator with variable reference
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/02—Circuit arrangements for generating control signals
    • F02D41/14—Introducing closed-loop corrections
    • F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
    • F02D41/1477—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the regulation circuit or part of it,(e.g. comparator, PI regulator, output)
    • F02D41/148—Using a plurality of comparators

Definitions

  • the invention relates to a device according to the preamble of the main claim.
  • a device DE-OS 27 07 383
  • the control device is controlled with the output value of this comparison device.
  • the output values of both comparison devices provide information about the operational readiness of the lambda probe.
  • the temperature at which operational readiness is recognized is the same for a lean and rich mixture.
  • this arrangement has the disadvantage that the control device is switched on and off several times, so that the control device cannot be used soon.
  • the engine is operated while idling, the period in which the control device is switched on and off can be repeated several times and thus lead to unfavorable engine running behavior, the so-called idling saws.
  • the device according to the invention for controlling the air-fuel ratio with the characterizing features of the main claim has the advantage that the control device is only switched on when the engine has reached an operating temperature that prevents the control device from being switched off again.
  • FIG. 1 shows an exemplary embodiment according to the invention
  • FIG. 2 shows a diagram to explain the functioning of control devices according to the prior art
  • FIG. 3 shows a diagram to explain the functioning of the control device according to the invention.
  • the solution according to the invention is a further development of the device described in DE-OS 2T 07 383.
  • the essential part of the A according to the invention Direction is a lambda probe of a known type, which is inserted into the exhaust system of an internal combustion engine and which is flown around by the exhaust gases resulting from the combustion processes in the cylinders of the internal combustion engine.
  • the probe consists of a solid electrolyte, for example zirconium dioxide, which is contacted on both sides. One side of the zirconia body is exposed to the exhaust gas and the other side to a reference medium.
  • a potential difference arises at the contacts.
  • the output voltage at the lambda probe assumes values of 750 to 900 mV, provided that the lambda probe is in the warm operating state.
  • the output voltage is approx. 100 mV.
  • the lambda probe has the disadvantage that the internal resistance of the probe is extremely high in the cold state, so that no voltage signal usable for regulation, in particular no significant voltage jump, can be achieved at the output of the lambda probe.
  • 1 shows the lambda probe 1 as an equivalent circuit diagram, consisting of a voltage source 2 and the temperature-dependent internal resistance 3.
  • the lambda probe is used in the exhaust system, not shown, of an internal combustion engine.
  • the internal combustion engine is supplied with an operating mixture of fuel and air by means of a fuel-air metering device, which mixture is combusted in the combustion chambers of the internal combustion engine.
  • the ratio of Fuel to air can be set in a controlled manner in the fuel-air metering device and corrected with a control device.
  • the aim is to have the overlying control device for metering fuel and air come into effect as early as possible after the internal combustion engine has been started up.
  • a circuit has been proposed in DE-OS 27 07 383 with which an output voltage of the probe that changes with the size of the internal resistance is sensed with the aid of threshold switches , a signal being generated after the predetermined threshold values are exceeded, which starts the control.
  • 1 shows a section of this circuit arrangement.
  • 1 is the lambda probe, which has a voltage source 2 and a temperature-dependent resistor 3.
  • a DC voltage source 5 with a series resistor 4 is connected in series with the lambda probe 1.
  • a voltage U A is tapped at the lambda probe 1, which leads to an input of threshold value amplifiers 9 and 10. The voltage U is passed via a further line to a control device, not shown.
  • Three resistors 6, 7 and 8 are connected between the positive supply voltage and the ground. Between the resistors 6 and 7, a signal is fed to the threshold amplifier 9 and thus the upper switch-on threshold is set. Another signal is tapped between the resistors 7 and 8 and fed to the threshold amplifier 10. This sets the lower threshold.
  • the output signals of the Threshold switches can be further processed, for example, as proposed in DE-OS 27 07 383.
  • the probe voltage U S which is necessary for U A to reach the upper switching threshold, which is set on the threshold value amplifier 9, at a predetermined value of the temperature-dependent resistor 3, is called the effective switching threshold U.
  • U max max and U min are shown in FIG. 2.
  • the curves of the maximum and minimum probe voltages that occur in the application are shown in solid lines.
  • the controller is set to a fixed control value.
  • the exhaust gas mixture is usually rich (lambda less than 1).
  • the threshold U max is therefore exceeded and the PI controller is switched to control.
  • the PI controller regulates towards a lean mixture.
  • the PI controller is switched off again and a fixed control value is specified.
  • the circuit arrangement according to the invention takes advantage of the effect that the direction of travel of the PI controller is only dependent on the position of the output voltage U A in relation to the lower threshold. If U max is exceeded or if the probe voltage is between U max and U min , the PI controller regulates the gasoline mixture to lean. Ranging from Umax to U min additional O ver w a monitoring time from running.
  • the PI controller is set to a control value.
  • the gasoline mixture is regulated to rich only when the output voltage U A falls below the lower threshold. Without changing the control properties, it is therefore possible to shift the upper threshold voltage U max so that the controller is only switched on at higher temperatures.
  • U max is only reached at temperature T 2 .
  • the PI controller regulates the mixture to rich again, ie there is no need to switch to the control value.
  • the regulation is thus immediately ready for operation, without having to switch back and forth between the regulation and regulation. With this measure, an early start of control can be achieved without idling saws occurring in the engine.
  • the probe input circuit with the probe 1, the resistor 4 and the DC voltage source 5 is defined as follows:
  • the rich on-resistance is the probe internal resistance 3, at which the effective switching threshold U max is 0.8 V.
  • the lean on resistance is the probe resistance at which the effective switching threshold U min is 0.1 V.
  • the rich and the lean internal probe resistance were set the same and were in the range of 1 to 2 M ⁇ .
  • the new dimensioning of the probe input circuit differs from the old dimensioning by the position of the switch-on resistors.
  • the switching voltage Umax is shifted towards higher temperatures by the selection of a small, thick switch-on resistance, which is, for example, in the range 100-200 k, while the lower voltage U min is maintained in its original form by maintaining the lean switch-on resistor (1 to 2 M ⁇ ) is maintained.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
  • Combined Controls Of Internal Combustion Engines (AREA)

Abstract

Es wird eine Einrichtung zur Regelung des Luft-Kraftstoffverhältnisses des Betriebsgemisches einer Brennkraftmaschine und zur Überwachung der Betriebsbereitschaft einer die Regeleinrichtung steuernden, nach dem Prinzip der Ionenleitung in Festelektrolyten arbeitenden Lambda-Sonde vorgeschlagen. Dabei wird der Lambda-Sonde eine einstellbare konstante Bezugsspannung, die etwa der mittleren Sondenausgangsspannung entspricht, entgegengeschaltet. Die Höhe der sich unter Mitwirkung des resultierenden Stromes einstellenden resultierenden Spannung wird durch Vergleichseinrichtungen überpruft, deren Ausgangssignale, logisch verwertet, ein Signal über den Betriebsbereitschaftszustand abgeben. Die Sondenbetriebsbereifschaftstemperatur bei magerem und fettem Gemisch ist unsymmetrisch gewählt, so daß nach dem Erkennen des Betriebsbereitschaftszustandes die Regelung störungsfrei funktionieren kann.A device for regulating the air-fuel ratio of the operating mixture of an internal combustion engine and for monitoring the operational readiness of a lambda probe which controls the regulating device and works on the principle of ion conduction in solid electrolytes is proposed. An adjustable constant reference voltage, which corresponds approximately to the mean probe output voltage, is switched in series with the lambda probe. The level of the resulting voltage resulting from the participation of the resulting current is checked by comparison devices, whose output signals, logically evaluated, emit a signal about the operational readiness state. The probe operating temperature in the case of a lean and rich mixture is chosen asymmetrically so that the control can function properly after the operational readiness has been recognized.

Description

Stand der TechnikState of the art

Die Erfindung geht aus von einer Einrichtung gemäß der Gattung des Hauptanspruchs. Bei einer solchen Einrichtung (DE-OS 27 07 383) dient die eine der Vergleichseinrichtungen dazu, festzustellen, ob das Sondensignal größer oder kleiner ist als ein mittlerer Spannungswert, der als den Regelpunkt bestimmender Spannungswert innerhalb des Spannungssprungs des Lambda-Sondenausgangssignals bei Lambda = λo liegt. Mit dem Ausgangswert dieser Vergleichseinrichtung wird die Regeleinrichtung gesteuert. Die Ausgangswerte beider Vergleichseinrichtungen stellen eine Aussage über die Betriebsbereitschaft der Lambda-Sonde dar. Bei bekannten Einrichtungen ist die Temperatur, bei der Betriebsbereitschaft erkannt wird, bei mageren und fettem Gemisch gleich groß. Diese Anordnung hat jedoch den Nachteil, daß die Regeleinrichtung mehrmals ein- und ausgeschaltet wird, so daß ein baldiges Einsetzen der Regeleinrichtung nicht gewährleistet ist. Insbesondere, wenn der Motor während des Warmlaufens im Leerlauf betrieben wird, kann der Zeitraum, in dem die Regeleinrichtung ein- und ausgeschaltet wird, sich mehrmals wiederholen und damit zu einem ungünstigen Motorlaufverhalten, dem sogenannten Leerlaufsägen, führen.The invention relates to a device according to the preamble of the main claim. In such a device (DE-OS 27 07 383), one of the comparison devices is used to determine whether the probe signal is larger or smaller than an average voltage value, the voltage value determining the control point within the voltage jump of the lambda probe output signal at lambda = λo lies. The control device is controlled with the output value of this comparison device. The output values of both comparison devices provide information about the operational readiness of the lambda probe. In known devices, the temperature at which operational readiness is recognized is the same for a lean and rich mixture. However, this arrangement has the disadvantage that the control device is switched on and off several times, so that the control device cannot be used soon. In particular, if the engine is operated while idling, the period in which the control device is switched on and off can be repeated several times and thus lead to unfavorable engine running behavior, the so-called idling saws.

Vorteile der ErfindungAdvantages of the invention

Die erfindungsgemäße Einrichtung zur Regelung des Kraftstoff-Luftverhältnisses mit den kennzeichnenden Merkmalen des Hauptanspruchs hat demgegenüber den Vorteil, daß die Regeleinrichtung erst dann eingeschaltet wird, wenn der Motor eine Betriebstemperatur erreicht hat, die ein Wiederausschalten der Regeleinrichtung verhindert.The device according to the invention for controlling the air-fuel ratio with the characterizing features of the main claim has the advantage that the control device is only switched on when the engine has reached an operating temperature that prevents the control device from being switched off again.

Durch den Unteranspruch ist eine vorteilhafte Weiterbildung und Verbesserung der im Hauptanspruch angegebenen Einrichtung möglich. Durch die sich ergebende asymmetrische Einschalt-Widerstandskennlinie wird erreicht, daß die Regeleinrichtung sofort nach dem Einschalten ein günstiges Regelverhalten zeigt.An advantageous further development and improvement of the device specified in the main claim is possible through the subclaim. The resultant asymmetrical switch-on resistance characteristic ensures that the control device shows favorable control behavior immediately after switching on.

Zeichnungdrawing

Ein Ausführungsbeispiel der Erfindung ist in der Zeichnung dargestellt und wird in der nachfolgenden Beschreibung näher erläutert. Es zeigen Fig. 1 ein Ausführungsbeispiel nach der Erfindung, Fig. 2 ein Diagramm zur Erläuterung der Funktionsweise von Regeleinrichtungen nach dem Stand der Technik und Fig. 3 ein Diagramm zur Erläuterung der Funktionsweise der erfindungsgemäßen Regeleinrichtung.An embodiment of the invention is shown in the drawing and is explained in more detail in the following description. 1 shows an exemplary embodiment according to the invention, FIG. 2 shows a diagram to explain the functioning of control devices according to the prior art, and FIG. 3 shows a diagram to explain the functioning of the control device according to the invention.

Beschreibung des AusführungsbeispielsDescription of the embodiment

Die erfindungsgemäße Lösung ist eine Weiterentwicklung der in der DE-OS 2T 07 383 beschriebenen Vorrichtung. Der wesentliche Bestandteil der erfindungsgemäßen Einrichtung ist eine Lambda-Sonde bekannter Bauart, die in das Abgassystem einer Brennkraftmaschine eingesetzt ist und die von den aus den Verbrennungsvorgängen in den Zylindern der Brennkraftmaschine resultierenden Abgasen umströmt wird. Die Sonde besteht aus einem Festelektrolyten, beispielsweise Zirkondioxid, der beiderseitig kontaktiert ist. Die eine Seite des Zirkondioxidkörpers ist dem Abgas und die andere Seite einem Bezugsmedium ausgesetzt. Infolge einer Sauerstoffpartialdruckdifferenz zwischen den Drücken an den beiden Oberflächen des Festelektrolytkörpers ergibt sich an den Kontaktierungen eine Potentialdifferenz. Die Ausgangsspannung der Lambda-Sonde ändert sich bei einer Luftzahl Lambda =λ sprungartig. Bei Luftzahlen Lambda kleinere nimmt die Ausgangsspannung an der Lambda-Sonde Werte von 750 bis 900 mV an, vorausgesetzt, daß die Lambda-Sonde sich im betriebswarmen Zustand befindet. Bei Luftzahlen Lambda größer 10 beträgt die Ausgangsspannung ca. 100 mV.The solution according to the invention is a further development of the device described in DE-OS 2T 07 383. The essential part of the A according to the invention Direction is a lambda probe of a known type, which is inserted into the exhaust system of an internal combustion engine and which is flown around by the exhaust gases resulting from the combustion processes in the cylinders of the internal combustion engine. The probe consists of a solid electrolyte, for example zirconium dioxide, which is contacted on both sides. One side of the zirconia body is exposed to the exhaust gas and the other side to a reference medium. As a result of an oxygen partial pressure difference between the pressures on the two surfaces of the solid electrolyte body, a potential difference arises at the contacts. The output voltage of the lambda probe changes suddenly with an air ratio lambda = λ. In the case of lambda air numbers smaller, the output voltage at the lambda probe assumes values of 750 to 900 mV, provided that the lambda probe is in the warm operating state. With air numbers lambda greater than 1 0 , the output voltage is approx. 100 mV.

Die Lambda-Sonde weist jedoch den Nachteil auf, daß im kalten Zustand der Innenwiderstand der Sonde extrem hoch ist, so daß sich am Ausgang der Lambda-Sonde kein für eine Regelung verwertbares Spannungssignal, insbesondere kein deutlicher Spannungssprung erzielen läßt. In Fig. 1 ist die Lambda-Sonde 1 als Ersatzschaltbild wiedergegeben, bestehend aus einer Spannungsquelle 2 und dem temperaturabhängigen Innenwiderstand 3. Die Lambda-Sonde ist in dem nicht dargestellten Abgassystem einer Brennkraftmaschine eingesetzt. Die Brennkraftmaschine wird mittels einer Kraftstoff-Luftdosiereinrichtung mit Betriebsgemisch aus Kraftstoff und Luft versorgt, das in den Brennräumen der Brennkraftmaschine zur Verbrennung gelangt. Das Verhältnis von Kraftstoff zu Luft kann in der Kraftstoff-Luftdosiereinrichtung gesteuert eingestellt werden und mit einer Regeleinrichtung korrigiert werden.However, the lambda probe has the disadvantage that the internal resistance of the probe is extremely high in the cold state, so that no voltage signal usable for regulation, in particular no significant voltage jump, can be achieved at the output of the lambda probe. 1 shows the lambda probe 1 as an equivalent circuit diagram, consisting of a voltage source 2 and the temperature-dependent internal resistance 3. The lambda probe is used in the exhaust system, not shown, of an internal combustion engine. The internal combustion engine is supplied with an operating mixture of fuel and air by means of a fuel-air metering device, which mixture is combusted in the combustion chambers of the internal combustion engine. The ratio of Fuel to air can be set in a controlled manner in the fuel-air metering device and corrected with a control device.

Im Interesse der Schadstoffreiheit der Abgase wird es angestrebt, die überlagernde Regeleinrichtung für die Kraftstoff- bzw. Luftdosierung möglichst frühzeitig nach Inbetriebnahme der Brennkraftmaschine zur Wirkung zu kommen lassen. Zur Erkennung, wann ein gerade noch mit ausreichender Sicherheit von der Regeleinrichtung verwertbares Sondensignal auftritt, ist in der DE-OS 27 07 383 eine Schaltung vorgeschlagen worden, mit der eine sich mit der Größe des Innenwiderstands ändernde Ausgangsspannung der Sonde mit Hilfe von Schwellwertschaltern abgetastet wird, wobei nach Überschreiten der festgelegten Schwellwerte ein Signal erzeugt wird, das die Regelung in Betrieb nimmt.In order to ensure that the exhaust gases are free of pollutants, the aim is to have the overlying control device for metering fuel and air come into effect as early as possible after the internal combustion engine has been started up. In order to detect when a probe signal that can still be used with sufficient certainty by the control device occurs, a circuit has been proposed in DE-OS 27 07 383 with which an output voltage of the probe that changes with the size of the internal resistance is sensed with the aid of threshold switches , a signal being generated after the predetermined threshold values are exceeded, which starts the control.

Die Fig. 1 zeigt einen Ausschnitt dieser Schaltungsanordnung. Mit 1 ist die Lambda-Sonde bezeichnet, die eine Spannungsquelle 2 und einen temperaturabhängigen Widerstand 3 aufweist. Eine Gleichspannungsquelle 5 mit einem Vorwiderstand 4 ist mit der Lambda-Sonde 1 in Reihe geschaltet. An der Lambda-Sonde 1 wird eine Spannung UA abgegriffen, die jeweils zu einem Eingang von Schwellwertverstärkern 9 und 10 führt. Die Spannung U wird über eine weitere Leitung zu einer nicht dargestellten Regeleinrichtung geleitet. Drei Widerstände 6, 7 und 8 sind zwischen der positiven Versorgungsspannung und der Masse geschaltet. Zwischen den Widerständen 6 und 7 wird ein Signal dem Schwellwertverstärker 9 zugeführt und damit die obere Einschaltschwelle festgelegt. Zwischen den Widerständen 7 und 8 wird ein weiteres Signal abgegriffen und dem Schwellwertverstärker 10 zugeführt. Hierdurch wird der untere Schwellwert festgelegt. Die Ausgangssignale der Schwellwertschalter sind beispielsweise wie in der DE-OS 27 07 383 vorgeschlagen, weiterverarbeitbar.1 shows a section of this circuit arrangement. 1 is the lambda probe, which has a voltage source 2 and a temperature-dependent resistor 3. A DC voltage source 5 with a series resistor 4 is connected in series with the lambda probe 1. A voltage U A is tapped at the lambda probe 1, which leads to an input of threshold value amplifiers 9 and 10. The voltage U is passed via a further line to a control device, not shown. Three resistors 6, 7 and 8 are connected between the positive supply voltage and the ground. Between the resistors 6 and 7, a signal is fed to the threshold amplifier 9 and thus the upper switch-on threshold is set. Another signal is tapped between the resistors 7 and 8 and fed to the threshold amplifier 10. This sets the lower threshold. The output signals of the Threshold switches can be further processed, for example, as proposed in DE-OS 27 07 383.

Bekannte Schaltungsanordnungen sind so definiert, daß die in Fig. 2 gezeigten Kurven auftreten. Die Spannung US der Spannungsquelle 2 der Lambda-Sonde 1, die notwendig ist, daß bei einem vorgegebenen temperaturabhängigen Widerstand 3 die Spannung UA die am unteren Schwellwertverstärker 10 festgelegte Schwelle erreicht, nennt man die effektive Schaltschwelle Umin. Die Sondenspannung US, die notwendig ist, damit UA bei einem vorgegebenen Wert des temperaturabhängigen Widerstandes 3 die obere Schaltschwelle, die am Schwellwertverstärker 9 eingestellt ist, erreicht, nennt man die effektive Schaltschwelle U . U max max und Umin sind in der Fig. 2 dargestellt. Außerdem sind die Verläufe der im Anwendungsfall vorkommenden maximalen und minimalen Sondenspannungen in durchgezogenen Linien dargestellt.Known circuit arrangements are defined such that the curves shown in FIG. 2 occur. The voltage U S of the voltage source 2 of the lambda probe 1, which is necessary for the voltage U A to reach the threshold set at the lower threshold amplifier 10 for a given temperature-dependent resistor 3, is called the effective switching threshold U min . The probe voltage U S , which is necessary for U A to reach the upper switching threshold, which is set on the threshold value amplifier 9, at a predetermined value of the temperature-dependent resistor 3, is called the effective switching threshold U. U max max and U min are shown in FIG. 2. In addition, the curves of the maximum and minimum probe voltages that occur in the application are shown in solid lines.

Während des Sondenwarmlaufs geschieht nun folgendes: Ist die Temperatur kleiner als die Temperatur T1, kann weder die Schwelle U noch die Schwelle U . erreicht werden. max min Nach Ablauf einer Überwachungszeit wird der Regler auf einen festen Steuerwert gesetzt. Während des Warmlaufens ist das Abgasgemisch üblicherweise fett (Lambda kleiner 1). Beim Erreichen der Temperatur T wird daher die Schwelle U max überschritten und der PI-Regler wird auf Regelung umgeschaltet. Der PI-Regler regelt dabei in Richtung auf ein mageres Gemisch hin. Die Sondenspannung US kann jedoch die Schwelle Umin nicht unterschreiten, da selbst in extremen Regelbereichen (Lambda = 1,2) die Schwelle U. nicht erreicht wird. Nach Ablauf einer Wartezeit min wird der PI-Regler wieder abgeschaltet und ein fester Steuerwert vorgegeben. Dies wiederholt sich so lange, bis die Sondentemperatur so hoch angestiegen ist, daß bei Lambda = 1,2 die untere Schwelle U . überschritten wird. Dieser Zeitraum kann so groß sein, daß sich dieser Vorgang mehrmals wiederholt und damit zu einem ungünstigen Motorlaufverhalten führt. Dieses Verhalten ist als sogenanntes Leerlaufsägen bekannt.The following now occurs during the probe warm-up: If the temperature is lower than the temperature T 1 , neither the threshold U nor the threshold U can. can be achieved. max min After a monitoring time has elapsed, the controller is set to a fixed control value. During warm-up, the exhaust gas mixture is usually rich (lambda less than 1). When the temperature T is reached, the threshold U max is therefore exceeded and the PI controller is switched to control. The PI controller regulates towards a lean mixture. However, the probe voltage U S cannot fall below the threshold U min , since the threshold U. is not reached even in extreme control ranges (lambda = 1.2). After a waiting time of min, the PI controller is switched off again and a fixed control value is specified. This is repeated until the probe temperature has risen so high that at Lambda = 1.2 the lower threshold U. is exceeded. This period can be so long that this process is repeated several times and thus leads to an unfavorable engine running behavior. This behavior is known as idle sawing.

In Fig. 3 ist der Kennlinienverlauf bei der erfindungsgemäßen Dimensionierung gezeigt. Die Spannung UO der Spannungsquelle 5 und der Widerstand 4 sind wieder konstant, wobei die Spannung UQ zwischen den beiden Schwellen der Schwellverstärker 9 und 10 liegt. Die Sondenspannung US ist eine Funktion der Temperatur und der Abgaszusammensetzung. Auch der Widerstand 3 ist temperaturabhängig. Die erfindungsgemäße Schaltungsanordnung macht sich den Effekt zunutze, daß die Laufrichtung des PI-Reglers nur von der Lage der Ausgangs- spannung UA zur unteren Schwelle abhängig ist. Wird nämlich Umax überschritten oder befindet sich die Son- denspannung zwischen Umax und Umin, regelt der PI-Regler das Benzingemisch nach mager. Im Bereich von U max bis Umin läuft zusätzlich eine Überwachungszeit ab. Nach Ablauf dieser Überwachungszeit wird der PI-Regler auf einen Steuerwert gesetzt. Bei Regelbetrieb allerdings wird das Benzingemisch nur dann nach fett geregelt, wenn die Ausgangsspannung UA die untere Schwelle unterschreitet. Ohne Änderung der Regeleigenschaften ist es daher möglich, die obere Schwellenspannung U max so zu verschieben, daß der Regler erst bei höheren Temperaturen eingeschaltet wird. Beim fetten Betrieb in der Warmlaufphase (Lambda kleiner 1) wird dabei U max erst bei der Temperatur T2 erreicht. Bei der Temperatur T2 wird der Regler eingeschaltet und regelt das Kraftstoffgemisch in Richtung mager. Bis der PI-Regler seine äußerste Magerstellung (Lambda = 1,2) erreicht hat, hat sich die Sonde soweit erwärmt, daß bei Lambda = 1,2 die Schwelle Umin unterschritten werden kann. Der PI-Regler regelt das Gemisch wieder nach fett, d. h. eine Umschaltung auf den Steuerwert entfällt. Die Regelung ist also sofort betriebsbereit, ohne daß ein vielfältiges Hin- und Herschalten zwischen Steuerung und Regelung erfolgt. Durch diese Maßnahme ist ein früher Regelbeginn erzielbar, ohne daß ein Leerlaufsägen im Motor auftritt.3 shows the course of the characteristic curve in the dimensioning according to the invention. The voltage U O of the voltage source 5 and the resistor 4 are again constant, the voltage U Q being between the two thresholds of the threshold amplifiers 9 and 10. The probe voltage U S is a function of the temperature and the exhaust gas composition. Resistor 3 is also temperature-dependent. The circuit arrangement according to the invention takes advantage of the effect that the direction of travel of the PI controller is only dependent on the position of the output voltage U A in relation to the lower threshold. If U max is exceeded or if the probe voltage is between U max and U min , the PI controller regulates the gasoline mixture to lean. Ranging from Umax to U min additional O ver w a monitoring time from running. After this monitoring time has expired, the PI controller is set to a control value. In regular operation, however, the gasoline mixture is regulated to rich only when the output voltage U A falls below the lower threshold. Without changing the control properties, it is therefore possible to shift the upper threshold voltage U max so that the controller is only switched on at higher temperatures. With rich operation in the warm-up phase (lambda less than 1), U max is only reached at temperature T 2 . At temperature T 2 , the controller is switched on and regulates the fuel mixture in the lean direction. Until the PI controller has reached its extreme lean position (lambda = 1.2), the The probe is heated to such an extent that the threshold U min can be undershot at lambda = 1.2. The PI controller regulates the mixture to rich again, ie there is no need to switch to the control value. The regulation is thus immediately ready for operation, without having to switch back and forth between the regulation and regulation. With this measure, an early start of control can be achieved without idling saws occurring in the engine.

In der Anwenderpraxis wird die Sondeneingangsschaltung mit der Sonde 1, dem Widerstand 4 und der Gleichspannungsquelle 5 folgendermaßen definiert: Der Fett-Einschaltwiderstand ist der Sondeninnenwiderstand 3, bei dem die effektive Schaltschwelle U max 0,8 V beträgt. Der magere Einschaltwiderstand ist der Sondenwiderstand, bei dem die effektive Schaltschwelle Umin 0,1 V beträgt. Bei bekannten Schaltungsanordnungen wurden der fette und der magere Sondeninnenwiderstand jeweils gleich festgelegt und lag im Bereich von 1 bis 2 MΩ. Die Neudimensionierung der Sondeneingangsschaltung unterscheidet sich von der alten Dimenionsierung durch die Lage der Einschaltwiderstände. Durch die Wahl eines kleinen fetten Einschaltwiderstandes, der beispielsweise im Bereich 100 - 200 k liegt, wird die Schaltspannung Umax in Richtung höherer Temperaturen verschoben, während die untere Spannung Umin durch die Beibehaltung des mageren Einschaltwiderstandes (1 bis 2 MΩ) in ihrer ursprünglichen Form beibehalten wird.In user practice, the probe input circuit with the probe 1, the resistor 4 and the DC voltage source 5 is defined as follows: The rich on-resistance is the probe internal resistance 3, at which the effective switching threshold U max is 0.8 V. The lean on resistance is the probe resistance at which the effective switching threshold U min is 0.1 V. In known circuit arrangements, the rich and the lean internal probe resistance were set the same and were in the range of 1 to 2 MΩ. The new dimensioning of the probe input circuit differs from the old dimensioning by the position of the switch-on resistors. The switching voltage Umax is shifted towards higher temperatures by the selection of a small, thick switch-on resistance, which is, for example, in the range 100-200 k, while the lower voltage U min is maintained in its original form by maintaining the lean switch-on resistor (1 to 2 MΩ) is maintained.

Claims (2)

1. Einrichtung zur Regelung des Kraftstoff-Luftverhältnisses des in einer Brennkraftmaschine zur Verbrennung kommenden Betriebsgemisches unter Verwendung einer Lambda-Sonde, die mit einer Regeleinrichtung zur Beeinflussung des Kraftstoff-Luftverhätnisses verbunden ist, sowie mit einer Einrichtung zur Überwachung-der Betriebsbereitschaft der Lambda-Sonde, wobei zur Erfassung des die Sonden be triebsbereitschaft beeinflussenden Sondeninnenwiderstands eine Bezugsspannung unter Zwischenschaltung eines Widerstands der Sondenspannung entgegengeschaltet wird und die resultierende Spannung (UA) am Lambda-Sondenausgang auf einen die Betriebsbereitschaft der Lambda-Sonde anzeigenden Mindesthub mittels wenigstens zweier Vergleichseinrichtungen mit verschiedenen Schwellwerten überprüfbar ist, deren Ausgänge als Maß für die Betriebsbereitschaft durch eine Auswerteschaltung verwertbar ist, durch welche ein den Betrieb der Regeleinrichtung ausschaltendes bzw. einschaltendes Signal erzeugt wird, dadurch gekennzeichnet, daß die Einschalttemperatur bzw. der Einschaltwiderstand für den fetten Sondenbetrieb zu höheren Temperaturen bzw. einen niedrigeren eingeschalteten Widerstand verschoben ist.1. Device for regulating the fuel-air ratio of the operating mixture to be burned in an internal combustion engine using a lambda probe, which is connected to a control device for influencing the fuel-air ratio, and with a device for monitoring the operational readiness of the lambda probe , in order to detect the operational resistance of the probes influencing the readiness of the probe, a reference voltage is interposed with the interposition of a resistance of the probe voltage and the resulting voltage (UA) at the lambda probe output can be checked for a minimum stroke indicating the operational readiness of the lambda probe by means of at least two comparison devices with different threshold values whose outputs can be used as a measure of the operational readiness by an evaluation circuit, by means of which a signal which switches the operation of the control device off or on is generated, therefore ch characterized in that the switch-on temperature or the switch-on resistance for the rich probe operation is shifted to higher temperatures or a lower switched-on resistance. 2. Einrichtung nach Anspruch 1, dadurch gekennzeichnet, daß die Einschalttemperatur bzw. der Einschaltwiderstand für den mageren Sondenbetrieb bei niedriger Temperatur bzw. hohem Einschaltwiderstand festgelegt ist.2. Device according to claim 1, characterized in that the switch-on temperature or the switch-on resistance for the lean probe operation at low temperature or high switch-on resistance is fixed.
EP82111154A 1981-12-11 1982-12-02 Apparatus for regulating the air-fuel ratio in an internal-combustion engine Expired EP0081759B1 (en)

Applications Claiming Priority (2)

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DE19813149136 DE3149136A1 (en) 1981-12-11 1981-12-11 DEVICE FOR REGULATING THE FUEL-AIR RATIO IN INTERNAL COMBUSTION ENGINES
DE3149136 1981-12-11

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EP0081759A2 true EP0081759A2 (en) 1983-06-22
EP0081759A3 EP0081759A3 (en) 1984-11-28
EP0081759B1 EP0081759B1 (en) 1988-03-16

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EP (1) EP0081759B1 (en)
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2570127A1 (en) * 1984-09-11 1986-03-14 Westfaelische Metall Industrie For combustion engine fuel-air mixture control system
WO1990005840A1 (en) * 1988-11-24 1990-05-31 Robert Bosch Gmbh Process and device for establishing at least one threshold voltage for a lambda closed-loop control
WO1990009517A1 (en) * 1989-02-18 1990-08-23 Robert Bosch Gmbh Process for checking the performance of a lambda sensor

Families Citing this family (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3149136A1 (en) * 1981-12-11 1983-06-23 Robert Bosch Gmbh, 7000 Stuttgart DEVICE FOR REGULATING THE FUEL-AIR RATIO IN INTERNAL COMBUSTION ENGINES
JPS6090937A (en) * 1983-10-22 1985-05-22 Nippon Denso Co Ltd Air-fuel ratio controlling apparatus
JPS60235050A (en) * 1984-05-07 1985-11-21 Toyota Motor Corp Method for controlling current supplied to electric heater of oxygen sensor
DE3727573A1 (en) * 1987-08-19 1989-03-02 Bosch Gmbh Robert METHOD AND DEVICE FOR WARM-UP, FULL-LOAD AND Lean-regulation of an Internal Combustion Engine at a Specified Lambda Value
US5337722A (en) * 1992-04-16 1994-08-16 Yamaha Hatsudoki Kabushiki Kaisha Fuel control and feed system for gas fueled engine
US5575266A (en) * 1993-08-31 1996-11-19 Yamaha Hatsudoki Kabushiki Kaisha Method of operating gaseous fueled engine
JP3139592B2 (en) * 1993-08-31 2001-03-05 ヤマハ発動機株式会社 Gas-fuel mixture mixture formation device
US5546919A (en) * 1993-08-31 1996-08-20 Yamaha Hatsudoki Kabushiki Kaisha Operating arrangement for gaseous fueled engine
US5392643A (en) * 1993-11-22 1995-02-28 Chrysler Corporation Oxygen heater sensor diagnostic routine
DE4402618C2 (en) * 1994-01-28 1998-04-30 Uwe Bastian Method and measuring arrangement for checking the lambda control loop in the case of regulated exhaust gas catalysts
JPH07253049A (en) * 1994-03-14 1995-10-03 Yamaha Motor Co Ltd Fuel supply device for gaseous fuel engine
JPH07253048A (en) * 1994-03-15 1995-10-03 Yamaha Motor Co Ltd Air-fuel mixture forming method of gaseous fuel engine and device thereof
DE19729696C2 (en) * 1997-07-11 2002-02-21 Bosch Gmbh Robert Method and device for monitoring the function of a gas probe
US6176224B1 (en) 1998-03-30 2001-01-23 Caterpillar Inc. Method of operating an internal combustion engine which uses a low energy gaseous fuel
EP1732523B9 (en) 2004-03-30 2010-06-02 Relypsa, Inc. Potassium binding polymers and uses thereof
US7854924B2 (en) * 2004-03-30 2010-12-21 Relypsa, Inc. Methods and compositions for treatment of ion imbalances
DE102004050092B3 (en) * 2004-10-14 2006-04-13 Siemens Ag Method for controlling the lambda value of an internal combustion engine
CA2624170C (en) 2005-09-30 2014-02-25 Ilypsa, Inc. Methods and compositions for selectively removing potassium ion from the gastrointestinal tract of a mammal
GB2446076B (en) * 2005-09-30 2010-11-24 Ilypsa Inc Methods for preparing core-shell composites having cross-linked shells and core-shell composites resulting therefrom
US20100104527A1 (en) * 2008-08-22 2010-04-29 Relypsa, Inc. Treating hyperkalemia with crosslinked cation exchange polymers of improved physical properties
US8337824B2 (en) 2008-08-22 2012-12-25 Relypsa, Inc. Linear polyol stabilized polyfluoroacrylate compositions
KR20210005314A (en) 2012-10-08 2021-01-13 리립사, 인크. Potassium-binding agents for treating hypertension and hyperkalemia

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2707383A1 (en) * 1977-02-21 1978-08-24 Bosch Gmbh Robert METHOD AND DEVICE FOR MONITORING THE OPERATIONAL READINESS OF A LAMBDA PROBE
GB2060177A (en) * 1979-10-09 1981-04-29 Nissan Motor System for feedback control of air-fuel ration in ic engine with subsystem to control current supply to oxygen sensor

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE411784B (en) * 1975-04-18 1980-02-04 Bosch Gmbh Robert SET AND DEVICE FOR DETERMINING THE DURATION OF FUEL SUPPLY PULSE
DE2649272C2 (en) * 1976-05-22 1986-04-03 Robert Bosch Gmbh, 7000 Stuttgart Control method and mixture ratio control device for determining the proportions of a fuel-air mixture fed to an internal combustion engine
JPS5382927A (en) * 1976-12-28 1978-07-21 Nissan Motor Co Ltd Air-fuel ratio controlling apparatus
DE2700629A1 (en) * 1977-01-08 1978-07-20 Bosch Gmbh Robert DEVICE FOR DETECTING THE READINESS OF A LAMBDA PROBE
US4263652A (en) * 1978-02-27 1981-04-21 The Bendix Corporation Oxygen sensor signal conditioner
DE2919220A1 (en) * 1979-05-12 1980-11-27 Bosch Gmbh Robert METHOD FOR REGULATING THE FUEL / AIR RATIO IN INTERNAL COMBUSTION ENGINES
DE3024607A1 (en) * 1980-06-28 1982-02-04 Robert Bosch Gmbh, 7000 Stuttgart DEVICE FOR REGULATING THE FUEL / AIR RATIO IN INTERNAL COMBUSTION ENGINES
DE3149136A1 (en) * 1981-12-11 1983-06-23 Robert Bosch Gmbh, 7000 Stuttgart DEVICE FOR REGULATING THE FUEL-AIR RATIO IN INTERNAL COMBUSTION ENGINES

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2707383A1 (en) * 1977-02-21 1978-08-24 Bosch Gmbh Robert METHOD AND DEVICE FOR MONITORING THE OPERATIONAL READINESS OF A LAMBDA PROBE
GB2060177A (en) * 1979-10-09 1981-04-29 Nissan Motor System for feedback control of air-fuel ration in ic engine with subsystem to control current supply to oxygen sensor

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2570127A1 (en) * 1984-09-11 1986-03-14 Westfaelische Metall Industrie For combustion engine fuel-air mixture control system
WO1990005840A1 (en) * 1988-11-24 1990-05-31 Robert Bosch Gmbh Process and device for establishing at least one threshold voltage for a lambda closed-loop control
WO1990009517A1 (en) * 1989-02-18 1990-08-23 Robert Bosch Gmbh Process for checking the performance of a lambda sensor

Also Published As

Publication number Publication date
EP0081759A3 (en) 1984-11-28
JPS58106152A (en) 1983-06-24
DE3149136A1 (en) 1983-06-23
EP0081759B1 (en) 1988-03-16
DE3149136C2 (en) 1990-05-31
US4492205A (en) 1985-01-08
JPH0380976B2 (en) 1991-12-26
DE3278245D1 (en) 1988-04-21

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