DE10211463B3 - Motor vehicle and method for automatically switching off and starting an internal combustion engine - Google Patents

Abstract

Motor vehicle and method for automatically switching off and starting an internal combustion engine (2) of the motor vehicle by means of a stop-start device (16). The stop-start device (16) monitors the motor vehicle doors (40) whether they are closed or open and causes the automatic shutdown and / or starting of the internal combustion engine depending on whether the motor vehicle doors (40) are closed or open are.

Description

The invention relates to a method for automatically switching off and starting an internal combustion engine according to the generic term of claim 1.

Furthermore, the invention relates to a Motor vehicle according to the preamble of claim 10.

A method and a motor vehicle of this kind are known from DE 32 12 843 C2 known. Similar procedures are also off DE 32 23 318 C2 . DE 32 28 561 C2 and DE 44 12 438 C1 known. In the process of DE 44 12 438 C1 the current internal combustion engine is automatically turned off by an electronic control device by interrupting the fuel supply when certain engine stop conditions are met over the duration of a predetermined dwell time. In a second method step, the previously parked internal combustion engine is restarted automatically by means of the control device, if certain engine start conditions are met. Belongs to the engine stop conditions that the driving speed of the motor vehicle is below a predetermined value, preferably 0 or at least smaller than a predetermined limit speed of z. B. 0.5 km / h, and the engine speed is at a closed traction drive clutch below a predetermined value. The engine start conditions include at least that no gear is engaged and that the clutch pedal is tapped, or that according to another embodiment, no transmission gear is engaged and the engine temperature has risen above a predetermined value.

DE 195 32 135 A1 also discloses a stop-start automatic system for switching off and starting the internal combustion engine of a motor vehicle depending on stop conditions or starting conditions. Zero load, coasting, idling of the drive unit (ie speed below a certain low value), standstill of the motor vehicle (ie driving speed below a certain small value of eg 4 km / h), disengaged drive unit, no gear engaged, are mentioned as starting conditions. the motor vehicle brake is actuated, actuation of a stop switch, operating temperature of the drive unit is reached and / or the state of charge of a battery sufficiently charged for further starting conditions. The stopping of the drive unit or of the internal combustion engine can take place either immediately upon the occurrence of the stop condition (ie with a very short reaction time) or delayed (for example with a reaction time of a few seconds). In the stop conditions can also enter into variables that relate to the driving history, z. B. it may be necessary that the vehicle is driven at least once since the last stop of the engine. It is also possible from the preceding driving characteristics to detect whether the vehicle is in city traffic, in a stop-and-go traffic congestion or in cross-country traffic. The response time may be adaptively variable depending on individual or operating conditions or the driving history. For example, in the case where the motor vehicle had to stop at many traffic lights in the near past, the reaction time can be automatically shortened or prolonged in the contrary case. The stop conditions may be alone or in subcombination and also in total combination (AND function). As start conditions, which may be alone or in subcombination or total combination (AND function), mention is made: actuation of the accelerator pedal, release of the motor vehicle brake, actuation of the clutch, touching or moving a gearshift lever, engaging a gear, pressing a start switch. Furthermore, further starting conditions may be required, for. B. that the engine is stationary and / or has been previously turned off by automatic stop. An "emergency start" can be triggered if z. B. the temperature of the engine drops below the operating temperature or the state of charge of the battery drops below a limit, but z. B. for powering air conditioners, servo drives, pumps or other auxiliary machinery is needed.

By the invention, the task to be solved to increase the operational safety.

This object is achieved according to the invention the characterizing features of claim 1 and claim 10 solved.

Further features of the invention are in the subclaims contain.

• 1 Details eines Kraftfahrzeuges nach der Erfindung,
• 2 eine Seitenansicht eines Kraftfahrzeuges nach der Erfindung,
• 3 ein Diagramm eines Teils eines Verfahrens nach der Erfindung,
• 4 ein Diagramm eines Teils eines weiteren Verfahrens nach der Erfindung,
• 5 ein Diagramm eines Teils eines weiteren Verfahrens nach der Erfindung.

The invention will now be described by way of example with reference to the drawings of preferred embodiments. In the drawings show

• 1 Details of a motor vehicle according to the invention,
• 2 a side view of a motor vehicle according to the invention,
• 3 a diagram of a part of a method according to the invention,
• 4 a diagram of a part of a further method according to the invention,
• 5 a diagram of a part of another method according to the invention.

1 shows an internal combustion engine 2 that has a switchable clutch 4 and a manual switchable or automatically switchable or automatic traction drive gearbox 6 and a differential gear 8th Motor vehicle wheels 10 and 12 drives. An electronic control device 14 for the internal combustion engine 2 is with him and preferably also with the gearbox 6 ever connected by control, especially if there is a switchable transmission 6 or an automatic transmission is. Furthermore, it is preferably also with the switchable coupling 4 connected by control. The electronic control device 14 also includes a stop-start facility 16 the type described here for automatically switching off and starting the engine 2 depending on the stop conditions and starting conditions described here.

1 further shows an electric machine 18 that of the electronic control device 14 is controllable to as an electric motor, the internal combustion engine 2 to start. Preferably, the electric machine 18 Also operable as a generator for generating power for an on-board battery 20 , This serves to supply power to the electrical machine 18 at the start of the internal combustion engine 2 and for powering auxiliary equipment such as an air conditioner 22 for the vehicle interior and at least one pump 24 for generating hydraulic pressures for actuating the traction drive clutch 4 and / or for the operation of clutches in the transmission 6 and / or for the circulation of coolant or lubricating fluid of the transmission 6 ,

According to the invention, the automatic shutdown and / or the automatic starting of the internal combustion engine takes place 2 depending on the respective operating state of a hood 26 , To the starting conditions for an automatic start of the internal combustion engine 2 heard that as an AND function at the same time the hood must be in the closed position, or, according to another embodiment, must be in a locked position.

According to a particular embodiment, the hood 26 two locking levels 28 and 30 of which the first locking stage 28 the hood 26 locked in their fully closed closed position and from the passenger compartment 32 is operable, and the second locking stage 30 the hood 26 locked in a slightly open, the fully closed closed position so far approximate part-open position that the hand of an adult person can not get through the opening gap in the engine compartment. To the starting conditions for an automatic start of the internal combustion engine 2 , which must be present as an AND function at the same time, heard that the hood 26 in the full closed position or at least in the partial open position and at the same time by at least one of the two locking stages 28 . 30 is locked.

Further shows 1 an accelerator pedal 34 for the internal combustion engine 2 and a brake pedal 36 for the vehicle brake 38 ,

According to a particular embodiment, all motor vehicle doors 40 , especially the driver's door, from the stop-start facility 16 monitors whether they are closed or open. The automatic shutdown and / or the automatic start of the internal combustion engine 2 takes place as a function of whether all motor vehicle doors are closed or at least one motor vehicle door is open. To the starting conditions, which must be met as an AND function at the same time, preferably belongs to all motor vehicle doors 40 are closed, so that an automatic starting of the internal combustion engine is omitted if at least one motor vehicle door is open.

A trunk door or trunk lid 42 is preferably included in the same way in the stop conditions and / or start conditions as the vehicle doors 40 , According to a further embodiment, the automatic shutdown of the internal combustion engine 2 depends on the further stop condition that a stop release from an air conditioner 22 present, which for the air conditioning of the motor vehicle passenger compartment 32 an example, connected to the internal combustion engine or connectable unit in the form of a refrigerant compressor 44 and / or a blower 46 having. If the air conditioning 22 just a blower 46 has, this serves only to promote fresh air from the outside atmosphere in the passenger compartment 32 , However, it is used depending on the climate setting for the promotion of fresh air, cooling air or hot air when the air conditioning 22 an air conditioner is and the refrigerant compressor 44 is provided.

A temperature sensor 48 the stop-start facility 16 detected in the person room 32 the temperature to maintain a comfortable for the driver and possibly also for riders temperature. A moisture sensor 50 the stop-start facility 16 detected in the person room 32 the humidity to maintain a humidity at which the vehicle windows 52 , especially the windshield, can not fog up. Windshield fogging would be a dangerous driving condition when the engine starts automatically.

According to a further embodiment, the automatic shutdown of the internal combustion engine takes place 2 through the stop-start facility 16 also depending on the operating status of an oil system 56 for the transmission 6 (Switching element actuation and / or cooling oil) and / or for a steering system 58 of the motor vehicle as another stop condition that must be met as an AND function at the same time with all other stop conditions. The automatic shutdown of the internal combustion engine 2 is omitted if all other stop conditions, However, this additional stop condition is not met. The oil system contains at least one oil pump 24 ,

3 shows on the horizontal axis the time and on the vertical axis different starting conditions for an automatic starting of the internal combustion engine after an automatic shutdown of the internal combustion engine by the stop-start device. At time t0, the internal combustion engine is in the automatically switched-off state or is switched off automatically. At time t1, at least one motor vehicle door is open, which is represented by a diagram line "S1". Simultaneously with the opening of the door, a start prohibit function is performed at time t1, which is shown by a diagram line "S2" and results in blocking the start function of the stop-start device at t1. At time t2, all doors are closed again, which also eliminates the start ban. Thereafter, at time t3, a start request is made by a driver of the motor vehicle, which is represented by a diagram line "S3". The start request, for example, the driver of the stop-start facility 16 be informed that it releases the vehicle brake and / or, gas and / or by touching or pressing a gear selector or other starting element, depending on the respective embodiment of the motor vehicle and the control device 14 , If all other starting conditions provided are met, the automatic starting of the internal combustion engine by the stop-start device is now carried out at time t3 either simultaneously or with a delay, depending on the embodiment 16 ,

The embodiment according to 3 has the advantage that the engine does not start automatically when the driver notifies his start request as the start condition of the stop-start device, although a vehicle door is open, eg when a child is getting off.

4 again shows a horizontal time axis t and a vertical situation axis or signal axis S.

At the time t1, a vehicle door is opened, which is shown by a diagram line "S1". Thus, a start prohibition is generated, which is represented by a diagram line "S2" and z. B. by a start prohibition signal can be realized, which causes a blocking of the start function or switching off the stop-start device. Thereafter, at the time t3, a start request of the driver, which is represented by a diagram line "S3", at a time at which the start prohibition "S2" still exists, since at least one motor vehicle door is open according to the diagram line "S1". The stop-start device is designed such that in this case (unlike in 3 ) Closing all doors does not cancel the start ban "S2". Thus, since this start condition is not satisfied, the engine is not automatically started by the stop-start device, although the start request "S3" is still present. The stop-start device is designed in such a way that in this case it can no longer automatically start the internal combustion engine, even if all starting conditions are met. The internal combustion engine can now only be restarted and started so that the driver performs a complete restart of the internal combustion engine by restarting the internal combustion engine with the ignition key or another ignition element at time t4 according to the diagram line S4.

example for 4 : The driver stops the motor vehicle, which operates the brake. The child gets out and leaves the door open. The driver leans to one side or turns back to close the vehicle door. He accidentally goes off the brake. Now in the case of 3 the engine is automatically started and started by the stop-start device as soon as the vehicle door is closed. Thus, the motor vehicle would start unintentionally in an automatic transmission, which could lead to an accident, for example at an intersection. The same situation according to 4 occurs even if the child closes the vehicle door itself, but the driver has previously accidentally released the vehicle brake. The term "brake" is used here generally for the normal vehicle brake as well as for a manually or by foot control detectable brake.

5 shows a diagram for a method or a motor vehicle according to the invention, in which at the time t0 of the internal combustion engine from the stop-start device 16 was switched off automatically. At time t1, the driver's door is opened corresponding to the line S1, thereby automatically setting a start prohibit signal according to line S2 at the same time. Thus, the automatic stop-start function is overridden beyond the time t2 at which the driver's door is closed again, so that the engine is not automatically started at the further time t3, although at this time corresponding to the line S3, a driver's request is present for starting and thus with the exception of the start condition for the driver's door all other starting conditions are met. The internal combustion engine can not be restarted automatically in this situation, but only by a person according to the line S4 manually using the ignition key or radio without the function of the stop-start device. This avoids that, after the driver has dropped out of the vehicle, children inadvertently, for example by releasing the brake or pressing the accelerator pedal 34 , start the combustion engine. This shows that embodiments of the invention are possible in which not all vehicle doors, but only the driver's door is monitored and their condition is considered as a start condition and / or as a stop condition.

At stopovers, when driving The idea is to reduce unnecessary fuel consumption via the electronic control unit 14 or the stop-start device 16 an automatic stop-start operation of the internal combustion engine 2 controlled. The function is performed on the basis of a priority list. The highest priority is safety, followed by comfort and maximum fuel economy.

• 1. Motorhaube geschlossen.
• 2. Kraftfahrzeug steht, wobei die Fahrzeuggeschwindigkeit gleich null oder null angenähert ist, beispielsweise kleiner oder gleich 0,5 km/h beträgt.
• 3. Gaspedal nicht betätigt.
• 4. Bremselement, z. B. Bremspedal oder eine manuell feststellbare Bremse oder eine Fuß-Feststellbremse, ist betätigt.
• 5. Alle Fahrzeugtüren und vorzugsweise auch eine Kofferraumtür oder ein Kofferraumdeckel, oder mindestens die Fahrertür, sind geschlossen.
• 6. Im Falle eines Automatikgetriebes steht der Wählhebel auf einer Fahrstellung, z. B. D, oder auf einer Neutralstellung, z. B. N.
• 7. Die Temperatur der Abgasanlage (z. B. Katalysatortemperatur) hat ihren Betriebswert erreicht.
• 8. Der Verbrennungsmotor (Öltemperatur und Kühlwassertemperatur) hat seine Betriebstemperatur erreicht.
• 9. Das Getriebe bzw, das Getriebeöl hat Betriebstemperatur erreicht und die Druckversorgung und damit die Schaltbarkeit des Getriebes sowie die Vermeidung einer Überhitzung im Getriebe ist auch bei ausgeschaltetem Motor sichergestellt.
• l0. Von der Klimasteuerung einer Klimatisiereinrichtung, z. B. Kühlgebläse und/oder Klimaanlage des Kraftfahrzeuges liegt eine Freigabe vor, durch welche sichergestellt ist, daß beispielsweise die Luftfeuchtigkeit im Kraftfahrzeug in Ordnung ist, die Fahrzeugscheiben nicht beschlagen können, und die Temperatur im Fahrzeuginneren innerhalb eines akzeptablen Toleranzbereiches liegt.
• 11. Es liegt eine Freigabe durch eine Batterie-Kontrolleinrichtung vor, durch welche beispielsweise sichergestellt wird, daß der Ladezustand der Fahrzeugbatterie ausreichend gut ist, um einen automatischen oder manuellen Neustart des Verbrennungsmotors sicherzustellen und auch ausreichend gut ist, um gegebenenfalls vorhandene andere Stromverbraucher des Kraftfahrzeuges während der Stophase ausreichend mit Strom zu versorgen.
• 12. Eine gegebenenfalls vorgesehene, und gegebenenfalls variable, Verzögerungszeit vor dem Aktivieren des MotorStops (Abschalten des Verbrennungsmotors) ist abgelaufen, ohne daß der Fahrer einen Startwunsch an die Antriebseinrichtung mitgeteilt hat, z. B. durch Lösen der Bremse und/oder Gasgeben und/oder Berühren oder Betätigen eines Gangwahlelementes. Eine vorgesehene Verzögerungszeit für das Abschalten des Verbrennungsmotors dient beispielsweise als Rangierschutz, z. B. vor dem Einlegen eines Rückwärtsganges, damit der Verbrennungsmotor nicht automatisch abgeschaltet wird, wenn das Fahrzeug nicht an einer Straßenampel oder in einem Stadtverkehr anhält, sondern zum Rangieren oder Rückwärtsfahren angehalten wurde. Durch die Möglichkeit, die Verzögerungszeit zu verkürzen oder zu überspringen, indem der Fahrer des Kraftfahrzeuges seinen Fahrwunsch der Antriebseinrichtung mitteilt, beispielsweise durch Berühren eines Getriebe-Wählhebels oder eines anderen Elements, wird auch ein zügiges Wiederanfahren bei kurzen Stops, z. B. beim Abbiegen während Gegenverkehr ermöglicht.
• 13. Ein Ein-Aus-Schalter zum wahlweisen manuellen Einschalten und Ausschalten der Stop-Start-Funktion ist im Einschalt-Zustand, nicht im Ausschalt-Zustand.

In the decision for an "automatic shutdown" of the internal combustion engine at least one, preferably more of the stop conditions mentioned in the patent application, optimally all stop conditions must be fulfilled, in each case in AND operation, for example:

• 1. Hood closed.
• 2. Motor vehicle stands, wherein the vehicle speed is equal to zero or zero, for example, less than or equal to 0.5 km / h.
• 3. Accelerator not actuated.
• 4. brake element, z. As brake pedal or a manually detectable brake or a foot parking brake is actuated.
• 5. All vehicle doors, and preferably also a trunk door or a boot lid, or at least the driver's door, are closed.
• 6. In the case of an automatic transmission, the selector lever is in a driving position, z. B. D, or at a neutral position, for. BN
• 7. The temperature of the exhaust system (eg, catalyst temperature) has reached its operating value.
• 8. The internal combustion engine (oil temperature and cooling water temperature) has reached its operating temperature.
• 9. The transmission or the transmission oil has reached operating temperature and the pressure supply and thus the shiftability of the transmission and the prevention of overheating in the transmission is ensured even when the engine is switched off.
• l0. From the climate control of an air conditioning, z. B. cooling fan and / or air conditioning of the motor vehicle is a release, by which it is ensured that, for example, the humidity in the motor vehicle is in order, the vehicle windows can not mist, and the temperature inside the vehicle is within an acceptable tolerance range.
• 11. There is a release by a battery control device, by which, for example, ensures that the state of charge of the vehicle battery is sufficiently good to ensure an automatic or manual restart of the engine and is also good enough to possibly present other power consumers of the motor vehicle to supply enough electricity during the stophase.
• 12. An optionally provided, and optionally variable, delay time before activating the engine stop (shutdown of the engine) has expired without the driver has communicated a start request to the drive device, for. B. by releasing the brake and / or accelerator and / or touching or pressing a gear selector element. An envisaged delay time for switching off the internal combustion engine serves, for example, as shunting, z. B. before engaging a reverse gear, so that the engine is not automatically switched off when the vehicle does not stop at a traffic light or in city traffic, but was stopped for maneuvering or reversing. By the ability to shorten the delay time or to skip by the driver of the motor vehicle tells his driving desire of the drive device, for example by touching a gear selector lever or other element, also a speedy restart in short stops, z. B. when turning during oncoming traffic allows.
• 13. An on-off switch for selectively switching on and off the stop-start function manually is in the on state, not in the off state.

Advantages:

Through the functions of the digits 1 to 6 and 12 the necessary safety (protection against incorrect operation) and a comfortable, simple and intuitive operation of the motor vehicle or its functions is ensured. By numeral 12 the function is optimized according to the driver's request, the driving style, the desired speed profile and the route. By the numbers 7 . 8th and 9 unnecessary cold starts and thus consumption, exhaust and wear disadvantages are prevented. By 11 a deterioration of the availability and reliability of the starting process of the motor vehicle is prevented. By 10 prevents an unpleasant high humidity in the passenger compartment of the vehicle is created and / or wet the vehicle windows damp and thereby the driver loses sight.

• 1. Aufgrund der Auswahl eines Betriebsmodus durch den Fahrer, z. B. über einen Economy-Wahlschalter oder -Wahltaster. Hierbei kann eine Aktivierung am Economy-Wählelement eine kleine Verzögerungszeit und eine Deaktivierung am Economy-Wählelement eine große Verzögerungszeit bewirken, wobei die Verzögerungszeit bis hin zu unendlich einstellbar sein kann.
• 2. Aufgrund der vorausgegangenen Fahrweise: Sportlicher Fahrer mit großen Pedalgradienten (große und/oder häufige Pedalbewegungen des Gaspedals und/oder des Bremspedals pro Zeiteinheit) ergeben eine große Verzögerungszeit, und ökonomische Fahrer mit kleinen Pedalgradienten ergeben eine kleine Verzögerungszeit.
• 3. Aufgrund des zurückgelegten Geschwindigkeitsprofils: Hohe Geschwindigkeiten, z. B. größer 100 km/h, Autobahn oder Landstraße, ergeben eine große Verzögerungszeit; kleine Geschwindigkeiten, z. B. kleiner 60 km/h, z. B. im Stadtverkehr oder stockender Verkehr, ergeben eine kleine Verzögerungszeit; dazwischen können mittlere Verzögerungszeiten liegen.
• 4. Aufgrund von Navigationsdaten eines Navigationssystems oder eines Verkehrsleitsystems oder von digitalen Straßenkarten, wobei beispielsweise Stausituationen eine kleine Verzögerungszeit ergeben können. Wenn der Verkehrsfluß blockiert ist, kann der Verbrennungsmotor, vorausgesetzt die übrigen Fahrbedingungen sind erfüllt, sofort abgeschaltet werden. Bei Abbiegesituationen und Kreuzungssituationen können große Verzögerungszeiten eingestellt werden, um ein störendes Abschalten in einer Abbiegesituation oder Kreuzungssituation zu verhindern.
• 5. Bremspedalwinkel: Kleine Pedalbetätigungswinkel, indem das Bremspedal wenig durchgetreten wird, können zur Einstellung einer großen Verzögerungszeit verwendet werden; große Bremspedal-Betätigungswinkel, indem das Bremspedal stark durchgetreten wird, können eine kleine Verzögerungszeit bewirken. Jedoch kann der Fahrer über das Bremspedal die Funktion intuitiv beeinflussen und steuern. Das "Bremspedal" ist hier nur ein Beispiel für jede Art von Fahrzeugbremselementen und Fahrzeug-Parkblockiereinrichtungen, beispielsweise einer manuellen Fahrzeug-Feststellbremse oder einer Fuß-Feststellbremse.

The said delay time for the automatic shutdown of the internal combustion engine in a vehicle stop is preferably variable and is preferably influenced by the following parameters, wherein a short delay time means an early shutdown of the internal combustion engine, and a long delay time a later shutdown of the internal combustion engine means:

• 1. Due to the selection of an operating mode by the driver, z. B. via an economy selector switch or selector switch. In this case, activation on the economy selection element can cause a small delay time and deactivation on the economy selection element a large delay time, the delay time can be adjustable to infinity.
• 2. Due to previous procedure: Sporty drivers with large pedal gradients (large and / or frequent pedal movements of accelerator and / or brake pedal per unit time) give a large delay time, and economical drivers with small pedal gradients give a small delay time.
• 3. Due to the traveled speed profile: high speeds, eg. B. greater than 100 km / h, highway or highway, give a large delay time; small speeds, z. B. less than 60 km / h, z. As in city traffic or stagnant traffic, resulting in a small delay time; in between, mean delay times can be.
• 4. Based on navigation data of a navigation system or a traffic control system or digital road maps, for example, congestion situations may result in a small delay time. If the traffic flow is blocked, the internal combustion engine, provided that the remaining driving conditions are met, can be switched off immediately. In turn-off situations and intersection situations, large delay times can be set to prevent disruptive shutdown in a turn-off situation or intersection situation.
• 5. Brake Pedal Angle: Small pedal actuation angles, by little depressing the brake pedal, can be used to set a long delay time; large brake pedal actuation angles, by strongly depressing the brake pedal, can cause a small delay time. However, the driver can intuitively influence and control the function via the brake pedal. The "brake pedal" is just one example of any type of vehicle brake elements and vehicle parking blocking devices, such as a manual vehicle parking brake or a foot parking brake.

• 1. Motorhaube geschlossen: Schutz bei Wartungs- oder Werkstattarbeiten. Beispiel: Der Fahrer fährt sein Fahrzeug in die Werkstatt oder eine Garage, hält an, öffnet die Motorhauben-Verriegelung, und während der Mechaniker gerade in den Motorraum greift lässt der Fahrer das Bremspedal los, was normalerweise ein Signal für den automatischen Start und damit das automatische Wiederanlassen des Verbrennungsmotors ist. In diesem Fall darf es nicht zu einem Motorneustart kommen.
• 2. Bremsbetätigungselement, z. B. Bremspedal: Bei aktivierter Fahrzeugbremse (Fußbremse, Handbremse, manuelle oder fußbetätigbare Feststellbremse) in der Stop-Phase wird unabhängig von der Bremspedalstellung bei Betätigung des Gaspedals oder beim Lösen der Fahrzeugbremse der Verbrennungsmotor gestartet. Wenn die Fahrzeugbremse in der Stophase nicht betätigt wurde, dann gilt vorzugsweise folgender Punkt 3.
• 3. Bremspedal nicht betätigt (Losgelassen) oder Fahrzeuggeschwindigkeit überschreitet einen Schwellwert, z. B. 5 km/h. Dieser zweite Fall kann auftreten bei noch betätigtem Bremspedal und Losrollen des Kraftfahrzeuges aufgrund eines starken Fahrbahngefälles.
• 4. Es müssen alle Fahrzeugtüren geschlossen sein, vorzugsweise auch eine Kofferraumtür oder ein Kofferraumdeckel, oder mindestens die Fahrertür.
• 5. Bei einem Automatikgetriebe muß die Wählhebelstellung je nach Ausführungsform des Kraftfahrzeuges in einer Vorwärtsfahrstellung, z. B. D, oder auf Neutralstellung, z. B. N, oder auf Parkstellung, z. B. P, sein.
• 6. Fahrer-Sicherheitsgurt ist angelegt und/oder das Gurtschloß ist geschlossen: Um auszuschließen, daß der Fahrer einen ungewollten Motorstart auslöst, indem er ungewollt die Fahrzeugbremse löst und/oder das Gaspedal betätigt, beispielsweise indem der Fahrer im Fahrzeug auf den Beifahrersitz hinüberrutscht, um z. B. einem anderen Fahrer Platz zu machen und dabei von der Bremse geht, oder der auf dem Fahrersitz sitzende Fahrer sich umdreht und nach hinten schaut, beispielsweise um von einem Rücksitz etwas zu holen oder sich dort mit einem Kind beschäftigt. In solchen Fällen wird ein automatischer Motorstart erst bei Betätigung des Gaspedals ausgelöst, auch dann, wenn der Fahrer den Sicherheitsgurt nicht angelegt oder das Gurtschloß nicht geschlossen hat.

When deciding to automatically start the internal combustion engine after an automatic stop, at least one or preferably more than one of the starting conditions mentioned in the sub-combination or preferably all of the patent applications must be fulfilled simultaneously as an AND function:

• 1. Bonnet closed: protection during maintenance or workshop work. Example: The driver drives his vehicle into the workshop or a garage, stops, opens the hood lock, and while the mechanic is just reaching into the engine compartment, the driver releases the brake pedal, which is usually a signal for the automatic start and thus the automatic restart of the internal combustion engine is. In this case, it may not come to a motor restart.
• 2. brake actuator, z. B. Brake pedal: When the vehicle brake (foot brake, handbrake, manual or foot-operated parking brake) is activated in the stop phase, the combustion engine is started independently of the brake pedal position when the accelerator pedal is depressed or when the vehicle brake is released. If the vehicle brake has not been actuated during the stophase, the following point 3 applies.
• 3. Brake pedal not depressed (released) or vehicle speed exceeds a threshold, eg. B. 5 km / h. This second case can occur when the brake pedal is still depressed and the vehicle is coasting due to a heavy road gradient.
• 4. All vehicle doors must be closed, preferably also a trunk door or a trunk lid, or at least the driver's door.
• 5. In an automatic transmission, the selector lever position depending on the embodiment of the motor vehicle in a forward position, z. B. D, or to neutral position, for. B. N, or parking position, z. B. P, be.
• 6. The driver seat belt is worn and / or the buckle is closed: To preclude the driver from triggering an unwanted engine start by accidentally releasing the vehicle brake and / or depressing the accelerator pedal, for example by the driver sliding into the passenger seat in the vehicle, to z. B. to make room for another driver and thereby goes from the brake, or the driver sitting on the driver's seat turns around and looks backwards, for example, to get something from a backseat or busy there with a child. In such cases, an automatic engine start is triggered only when the accelerator pedal, even if the driver has not put on the seat belt or the buckle has not closed.

Expansion options:

Triggering an engine stop already in deceleration phases or coasting phases of the motor vehicle to reduce fuel consumption. The prerequisite for this, however, is that the brake and steering remain fully functional when the engine is switched off. If this is not possible, it can be provided according to another embodiment, an intermediate solution in which not only the complete vehicle stop, but already when rolling out of the motor vehicle, an automatic engine stop occurs, however, with subsequent actuation of the brake or the steering during the vehicle coasting phase An immediate engine restart is automatic. Furthermore, it can be provided, a car perform matic engine stop only with active hill-hold function to prevent rolling back of the vehicle. Furthermore, it can be provided according to a further embodiment, that an automatic restart of the automatically switched off internal combustion engine takes place only when the accelerator pedal or another gas actuating element, regardless of whether a manually (hand brake) or operated by foot actuated vehicle brake, z. B. parking brake, in braking condition or not. The advantage of this: the normal vehicle brake, which does not serve to detect the motor vehicle, need not be kept pressed by the foot of a driver.

Claims (10)

Method for automatically switching off and starting an internal combustion engine ( 2 ) of a motor vehicle by means of a stop-start device ( 16 ), through which the internal combustion engine ( 2 ), after starting the internal combustion engine ( 2 ) by a person and driving the motor vehicle with an internal combustion engine ( 2 ), when stopping the motor vehicle and at the same time as AND function of certain stop conditions, to which at least the actuation of a motor vehicle brake ( 38 ) and a vehicle standstill or a low vehicle speed approximated to the vehicle standstill, is automatically switched off, and is then automatically restarted as AND function simultaneous occurrence of certain starting conditions, wherein the automatic shutdown of the internal combustion engine ( 2 ) by a stop function and then taking place automatic starting of the internal combustion engine ( 2 ) by a start function of the stop-start device ( 16 ), and wherein from the motor vehicle doors at least the driver's door ( 40 ) from the stop-start facility ( 16 ) is monitored, whether it is closed or open, and the automatic starting of the internal combustion engine ( 2 ) depending on whether the respective motor vehicle door has been opened after the automatic shutdown of the internal combustion engine, characterized in that the stop-start device ( 12 ) the closed state of a hood ( 26 ) of the motor vehicle is monitored and to the starting conditions, which must be met for an automatic starting of the internal combustion engine, a predetermined closed state of the hood ( 26 ), so that the internal combustion engine is no longer automatically startable, if this closed state is not given, in which case the internal combustion engine can only be initiated by renewed switching on of the ignition system by a person. Method according to Claim 1, characterized in that the starting conditions include that all motor vehicle doors ( 40 ) are closed, so that an automatic starting of the internal combustion engine ( 2 ) is omitted if at least one motor vehicle door is open. Method according to one of the preceding claims, characterized in that the stop conditions include that all motor vehicle doors ( 40 ) are closed, so that an automatic shutdown of the internal combustion engine ( 2 ) is omitted if at least one motor vehicle door is open. Method according to at least one of the preceding claims, characterized characterized in that the automatic stop-start function by opening a Motor vehicle door except Force is set when the affected motor vehicle door after the automatic shutdown of the internal combustion engine is opened, wherein the internal combustion engine is no longer automatically startable, even if the vehicle door in question is closed, but the internal combustion engine only through a complete restart can be started by switching off and restarting the ignition system of the internal combustion engine by a person. Method according to at least one of the preceding claims, characterized in that the starting signal to be triggered by a person for the automatic starting of the internal combustion engine ( 2 ) by means of the stop-start device ( 16 ) is triggered by the fact that the person the motor vehicle brake ( 38 ) releases. Method according to at least one of the preceding claims, characterized in that the starting signal to be triggered by a person for automatic starting of the internal combustion engine ( 2 ) by means of the stop-start device ( 16 ) is triggered by accelerating. Method according to at least one of the preceding claims, characterized in that a trunk lid ( 42 ) in the same way as a motor vehicle door ( 40 ) is included in the function of the stop-start device. Method according to at least one of the preceding claims, characterized in that the automatic shutdown of the internal combustion engine ( 2 ) additionally in dependence on the further stop condition that a stop-start device of an air-conditioning device ( 22 ), which for the air conditioning of the motor vehicle passenger compartment ( 32 ) with the internal combustion engine ( 2 ) drivingly connected or connectable unit in the form of a refrigerant compressor ( 44 ) and / or a blower ( 46 ) having. Method according to at least one of the preceding claims, that the automatic Ab switching the internal combustion engine ( 2 ) by the stop function of the stop-start device ( 16 ) depending on the operating state of an oil system ( 56 ) of a traction drive ( 6 ) takes place as an additional stop condition, which must be fulfilled as an AND function simultaneously with all other stop conditions, wherein the automatic shutdown of the internal combustion engine ( 2 ) is omitted, although all other stop conditions, but not this further stop condition is met, and wherein the oil system ( 56 ) at least one oil pump ( 24 ) contains. Motor vehicle with a stop-start device ( 16 ) for automatically switching off and starting an internal combustion engine ( 2 ), through which the internal combustion engine ( 2 ), after starting the internal combustion engine ( 2 ) by a person and driving the motor vehicle with an internal combustion engine ( 2 ), when stopping the motor vehicle and at the same time as AND function of certain stop conditions, to which at least the actuation of a motor vehicle brake ( 38 ) and a vehicle standstill or a low vehicle speed approximated to the vehicle standstill, is automatically switched off, and is then automatically restarted as AND function simultaneous occurrence of certain starting conditions, wherein the automatic shutdown of the internal combustion engine ( 2 ) by a stop function and then taking place automatic starting of the internal combustion engine by a start function of the stop-start device ( 16 ), characterized in that the stop-start device ( 16 ) Part of an electronic control device ( 14 ) for controlling the internal combustion engine ( 2 ) and is formed together with this for performing the method steps according to at least one of the preceding claims.