DE102007024352A1 - Method for operating motor vehicle system, executing function of motor vehicle system in repeated manner during operation of vehicle, where wear of motor vehicle influencing variables are determined - Google Patents

Abstract

The method involves executing a function of motor vehicle system in a repeated manner during the operation of the vehicle. The wear of the motor vehicle influencing variables are determined. The frequency, with which the function of the motor system is carried out, is varied according to determined wear of the motor vehicle influencing variables. An independent claim is also included for a device for operating a motor vehicle system.

Description

The The present invention relates to a method and an apparatus for operating a motor vehicle system, and according to a preferred application for operating a start-stop system in a motor vehicle.

Such start-stop systems are used to save fuel in a powered by an internal combustion engine motor vehicle. The start-stop system shuts the engine off when not in use and in response to the presence of one or more operating conditions (eg, accelerator pedal operation). Such vehicles with automatic, temporary shutdown of the engine are also referred to as micro-hybrid vehicles. For restarting the internal combustion engine, for example, a belt-driven integrated starter generator (BISG = "belt-driven integrated starter generator") can be used as it z. B. in the US 2004/0206325 A1 or the US 6 987 330 B2 is described and by means of which the crankshaft of the internal combustion engine is driven at a required restart.

From the US Pat. No. 6,664,651 B1 For example, a method and apparatus for controlling the idling speed of an internal combustion engine in a hybrid electric vehicle is known, wherein the internal combustion engine is switched off when, on the one hand, predetermined conditions are not present (eg a low battery state of charge) and, on the other hand, the internal combustion engine has been running for a long time predetermined period of time is in the idle state.

From the US 2004/0206325 A1 or the US 6,987,330 B2 For example, a method and an apparatus for controlling an internal combustion engine and a belt-driven integrated starter generator (BISG) are known wherein a stop pending state is maintained for a predetermined period of time prior to an automatic shutdown of the internal combustion engine still with respect to the shutdown sufficient to allow the driver a roll stop under immediate, re-start, without this is an automatic engine shutdown. For this purpose, a transition from the said intermediate state to the engine shutdown state takes place only when a delay time interval ("delay timeout value") is exceeded.

There The achievable by a start-stop system fuel savings the greater the effect Number of engine shutdowns, such systems are particular for use in commercial vehicles (eg in vehicles for parcel or food delivery) attractive. The behavior pattern the driver of such commercial vehicles performs during the life of the vehicle to a large number of Hundreds or thousands of stop-start cycles. This can, however cause the in the stop-start functionality involved vehicle components (such as the BISG) by too strong Accumulation of stop-start operations an excessive Wear, which in turn is premature Failure of these components compared to the overall lifetime of the vehicle and related necessary repairs, consequently Loss of use and, if necessary, loss of revenue for Episode has.

In front In the above background, it is an object of the present invention to a method and apparatus for operating a vehicle system provide by means of which an improved adaptation of a with a repeated execution of a function this Automotive system associated wear on the Wear of the entire system "motor vehicle" can be achieved can.

These Task is performed by a procedure with the characteristics of the independent Claim 1 and a device having the features of the independent Claim 8 solved.

One Method for operating a motor vehicle system, this motor vehicle system repeatedly during operation of the motor vehicle by means of execution operates at least one function of the motor vehicle system, has the following steps: detecting at least one of the wear of the motor vehicle influencing size, and varying the frequency, executed with the function of the motor vehicle system is determined, depending on the, the wear of the Motor vehicle influencing size.

According to a preferred application of the invention, the motor vehicle system is a start-stop system in a motor vehicle. In such a start-stop system, the number of "possible" start-stop operations is limited due to the wear associated with such start-stop operations, ie, the risk of component failure with a higher number of start-stop operations rises sharply. In this application of the invention, an optimal compromise can be achieved between the fuel savings achieved by the execution of the start-stop system and the wear associated with repeated execution of start-stop operations. In particular, it can be ensured that no wear-related failure of the motor vehicle occurs as a result of too large a number of start-stop processes before the end of the vehicle's service life due to certain others, the wear of the motor vehicle influence sender sizes (in particular mileage and operating time of the motor vehicle) is reached.

The However, the invention is not limited to this preferred application. but generally in conjunction with any automotive system can be used with a repeated execution of a Function of this motor vehicle system associated wear adjust the wear of the entire system "motor vehicle" to reduce.

According to one preferred embodiment comprises the step of varying the frequency with which the function of the motor vehicle system is executed, varying the value of a delay period depending on the detected the wear of the Motor vehicle influencing size, the Execution of the function of the motor vehicle system only when exceeded this delay period takes place.

According to one preferred embodiment, the value is varied the delay period as a function of at least one for the driving behavior of the motor vehicle characteristic size. This way you can the driving behavior of the motor vehicle is taken into account, by z. B. depending on the current mileage of the vehicle for the delay period is a larger one Value, a smaller value or the value zero is selected depending on whether, according to the current situation rather with the execution of the function the vehicle system associated wear, the the distance covered by the vehicle or the service life of the vehicle for limiting the life of the vehicle decisive factor. It is here and below under "operating time" the number of since the first commissioning of the Vehicle elapsed time (eg indicated by the number of Calendar days). Furthermore, here and below under "running track" the whole, since first commissioning of the Vehicle understood by this covered route.

According to one preferred embodiment, the frequency is varied, executed with the function of the motor vehicle system is, depending on a value determined for the driving behavior of the motor vehicle characteristic size either based on the distance traveled by the vehicle Driving distance or based on the operating time of the vehicle. On this way can z. B. in a vehicle in which due to high annual mileage covered by the vehicle Travel distance for limiting the life of the vehicle more decisive than the operating life of the vehicle is the Adaptation of the function of the motor vehicle system (eg number of Start-stop operations) targeted to the said route done so that - depending on driving behavior - a optimal selection of the reference relevant for the adaptation (eg travel distance or operating time) can be made.

According to one preferred embodiment is for the delay period only chosen a value greater than zero, if previously found to be fulfilling a on the frequency of execution of the function of the motor vehicle system related criterion for the expected life expectancy of the motor vehicle earlier is considered the fulfillment of one of the motor vehicle distance traveled criterion for the expected life of the motor vehicle, and / or performance a related to the operating life of the motor vehicle criterion for the expected life of the motor vehicle. This takes account of the fact that otherwise, namely, if it was determined that the route and / or the service life of the motor vehicle (and thus not the frequency of execution of the function of Automotive system, z. As the number of start-stop operations) crucial for the life-time limit are, also no delay period or reduction of said frequency is necessary, so that an unnecessary restriction of the function of the motor vehicle system (and thus an unnecessary reduction the achievable fuel savings) is avoided.

According to one preferred embodiment is characterized by on the frequency related to the execution of the function of the motor vehicle system Criterion for the expected service life of the motor vehicle an upper limit to the number of operation of the motor vehicle described stop-start operations described.

The Invention further relates to an apparatus for operating a motor vehicle system, which is designed to be a method with the above-described Perform characteristics. To preferred embodiments and Advantages of the device is based on the above statements referenced in connection with the method according to the invention.

Further Embodiments of the invention are the description and the dependent claims refer to.

The The invention will be described below with reference to the description and with reference to an embodiment shown in the accompanying drawings explained in more detail.

It demonstrate:

1 a diagram in which are plotted for different driving behavior, the covered by a motor vehicle running track and the number of engine stops per km over the operating time;

2 a flowchart for explaining a sequence of the method according to the invention according to a preferred embodiment;

3 a diagram for explaining the percentage of skipped engine shutdowns in response to the engine stop delay time; and

4 a schematic diagram for explaining the structure of a control system in which the inventive method is feasible.

Hereinafter, the inventive method with reference to the diagram of 1 as well as in 2 illustrated flowchart explained.

Usually, the criteria established by a vehicle manufacturer for achieving the planned service life of a motor vehicle include both a limit for the distance traveled (ie the service life of the vehicle is reached when a certain mileage of, for example, 250,000 km is exceeded) also a limit for the entire operating time (eg 10 years = 3650 days), which has elapsed since the first delivery of the motor vehicle to the customer. Decisive here is the criterion, which is met earlier, as in the following with reference to 1 is explained.

• I. Die Laufstrecke des Fahrzeuges überschreitet einen vorbestimmten ersten Grenzwert "B", z. B. 250.000 km; oder
• II. Die Betriebsdauer des Fahrzeuges überschreitet einen vorbestimmten zweiten Grenzwert "C", z. B. 10 Jahre = 3650 Tage.

In the diagram of 1 On the vertical axis, the total distance traveled by the vehicle (hereafter "running distance") is plotted, and the total life of the vehicle since the first delivery to the customer (hereafter "operating time") is plotted on the horizontal axis. The individual, in 1 Plotted graphs correspond to vehicles with different mileage per calendar year (eg 10,000 km per year, 15,000 km per year etc.). The end of the life of the motor vehicle is considered to have been reached if one of the following two criteria is met:

• I. The running distance of the vehicle exceeds a predetermined first limit value "B", z. 250,000 km; or
• II. The operating life of the vehicle exceeds a predetermined second threshold "C", z. B. 10 years = 3650 days.

• III. Die Gesamtzahl von Motorstartvorgängen überschreitet einen vorbestimmten dritten Grenzwert "A", z. B. 300000 Startvorgänge.

Furthermore, it is also believed that the life of the start-stop system is limited to a predetermined total number of engine starts. In the following example, this is based on an exemplary limit A = 300,000 starts. Another criterion for the end of the life of the motor vehicle is thus:

• III. The total number of engine starts exceeds a predetermined third threshold "A", e.g. B. 300000 starts.

In the diagram of 1 The solid line corresponds to a mileage of 25,000 km per year. For such an annual mileage, the limit values B = 250,000 km and C = 10 years assumed in the present example are achieved simultaneously. For those in the diagram of 1 above this solid line graph, the annual mileage is greater than 25,000 km per year, which results in the limit B for the running distance being reached before the limit value C for the duration of operation. Since only the attainment of one of the limit values B or C is decisive, the parameter "operating time" is irrelevant in these cases.

It is thus in this case by the invention Ensure that the limit A (i.e. Number of engine starts) not before the limit B (that is, reaching a running distance of 250,000 km) becomes. For this purpose, the number of Reboots limited to 300,000 / 250,000 = 1.2 restarts per kilometer. This means that in case, more than 1.2 restarts per kilometer, an ESD parameter is set to the ratio of restarts per kilometer to a value of a maximum of 1.2. Here is the ESD parameter a delay period for the shutdown of the internal combustion engine (ESD = "engine shut-down delay time"). If for the ratio of restarts per kilometer a value of 1.2 or less has been determined is no delay or definition of the ESD parameter required. A limit the number of restarts per year is not in this case required.

For example, for an annual mileage of 40,000 km, the running distance criterion versus the duration criterion is crucial, as the limit of 300,000 km is reached earlier than the limit of 10 years. In this case, to avoid premature failure of the start-stop system, ensure that after 250,000 km, a maximum of 300,000 start-stop operations have occurred. This is equivalent to a limit of 1.2 start-stop operations per kilometer traveled or (given in years, with the end of life after 250,000 km ≅ reaching 6.25 years is) a maximum number of 300,000 / 6.25 start-stop operations per year, ie 48,000 start-stop operations per year. This limit is also in 1 (upper row of numerical values).

For the in 1 below the solid line graph, the limit value C is reached for the operating time before the limit value B for the running distance.

In In this case, by the method according to the invention ensure that the limit A for the number of Restarts not before reaching the - here relevant - limit C for the operating time reached or exceeded becomes. The number of restarts per calendar year will therefore be at A / C = 300,000 / 10 = 30,000 restarts per calendar year, which is equivalent to 82.2 restarts per calendar day. If for the ratio of restarts per calendar year a value less than 82.2 is determined is no delay or definition of the ESD parameter required. If for however, this ratio of restarts per calendar year a value greater than 82.2 is determined, the ESD parameters set so that for the ratio restarts per calendar day have a value of 82.2 or less becomes. There is a limit to the number of restarts per kilometer not required in this case.

For example, for an annual mileage of 5,000 km, the duration criterion versus the running distance criterion is crucial, as the limit of 10 years is reached earlier than the limit of 30,000 km. In this case, to avoid premature failure of the start-stop system, ensure that after 10 years of driving a maximum of 300,000 start-stop operations have been made. This is equivalent to a limit of 300,000 / 10 start-stop operations per year or (given in km, since 1 year corresponds to a distance of 5000 km) a limitation to 6 start-stop operations per driven km. This limit is also in 1 (right vertical axis of the diagram).

Out The above explanations show that, for example in a vehicle with an annual mileage of 24,000 km with a maximum ratio of 1.2 restarts per kilometer and a maximum ratio of 82.2 restarts no determination of a delay period per calendar day (ESD parameter) is necessary.

• – Anzahl von Neustarts pro Tag;
• – Anzahl von Neustarts pro gefahrener Kilometer; und
• – Anzahl von gefahrenen Kilometern pro Tag

ermittelt. Dann erfolgt (z. B. einmal pro Tag) die Bewertung, ob einer der festgelegten Grenzwerte überschritten wird, und der Wert des ESD-Parameters wird dementsprechend reduziert oder erhöht. Da diese Bewertung des Erreichens der festgelegten Grenzwerte bzw. die Einstellung des Wertes des ESD-Parameters einmal täglich erfolgt, nähert sich das erfindungsgemäße Steuerungssystem einem Zustand, bei dem der Wert des ESD-Parameters optimal an die jeweils aktuelle Anzahl von Startvorgängen des Kraftfahrzeuges angepasst ist und auch unter ungünstigsten Bedingungen kein vorzeitiger Ausfall des Start-Stopp-Systems bzw. ein hierdurch bedingter Nutzungsausfall des Fahrzeuges stattfindet.According to the invention thus for a particular behavior pattern or driving behavior in each case z. B. Values averaged over a calendar day:

• - number of restarts per day;
• - number of restarts per kilometer driven; and
• - Number of kilometers driven per day

determined. Then, for example, once a day, the judgment is made as to whether one of the set limit values is exceeded, and the value of the ESD parameter is accordingly reduced or increased. Since this evaluation of the achievement of the specified limit values or the setting of the value of the ESD parameter takes place once a day, the control system according to the invention approaches a state in which the value of the ESD parameter is optimally adapted to the respectively current number of starting processes of the motor vehicle and even under the most unfavorable conditions no premature failure of the start-stop system or a consequent loss of use of the vehicle takes place.

There Also, the ESD value can also decrease by this is gradually reduced, if the respective driving behavior this permits (i.e., when the number of stop-start operations decreases), the controller according to the invention adapts to ESD parameters optimally depending on the driving behavior.

Hereinafter, the detailed procedure of the method in a preferred embodiment with reference to 2 described:
After the start (in step S0), first in step S1, a set point value (DT) is set to a value of 68.5 km / day (corresponding to 250,000 km / 3650 days), a "start per line limit value" (SKI ) to a value of 1.2 starts per km (corresponding to 300,000 starts / 250,000 km) and a "start per day limit" (SDL) to a value of 82.2 starts per day (corresponding to 300,000 starts / 3650 days) , At the same time a suitable target bandwidth (TB) of z. B. 5% fixed. The delay time span (ESD value) according to the invention is initially set to a value of 0 seconds.

In step S2, first, an engine start count value (A), a count value for the running distance (B), and a timer value (T) are each given the value zero. These values are further counted or accumulated in the subsequent step S3, after which a query is made in step S4 as to whether the timer value (T) exceeds the value of 24 hours. As soon as this is the case, in a further step S5 the values DPD = B / C (= running distance per day), SPD = A / C (= starts per day) and SPK = A / B (= starts per running distance) are determined , Then, in step S6, the query is made as to whether the DPD value for the running distance per day does not exceed the DT value, ie the distance setpoint. If this is the case, in step S7 the query is made as to whether the SPD value lies within the desired bandwidth TB about the SDL value. If this is the case, a Return to step S2. If this is not the case, a query is made in step S8 as to whether the SPD value exceeds the SDL value plus the setpoint bandwidth TB. If not, the ESD value is decreased by 1 second in step S9, and the process returns to step S2. If so, the ESD value is increased by 1 second in step S10, and a return to step S2 is also made.

If according to the query result of step S6, the DPD value (= Running distance per day) exceeds the set value (DT), in step S11, the query is made as to whether the SPK value (= starts per Running distance) within the target bandwidth TB by the distance limit SKI is located. If yes, a return to step S2. If not, in step S12 it is queried whether the SPK value (= Starts per run) the track limit SKI plus the Target bandwidth TB exceeds. This is not the case, At step S14, the ESD value is decreased by 1 second and it a return to step S2. Is this however Case, the ESD value is incremented by 1 second and it occurs also a return to step S2.

Since situations usually occur in which the driver decides to start again before the time period characterized by the ESD parameter has expired, a significant number of engine shut-down processes can be prevented by means of the introduction of the ESD parameter according to the invention. 3 shows a diagram for illustrative purposes, in which the percentage of skipped engine shutdown operations in dependence on the engine shut-off delay time is plotted.

According to 4 the construction of a control system in a motor vehicle is shown schematically, in which the inventive method is feasible.

According to 4 is an internal combustion engine 1 of the motor vehicle to implement a start-stop system to a belt-driven integrated starter generator (BISG = "belt-driven integrated starter generator") connected by a pulley 3 this starter generator 2 to a pulley 4 the crankshaft of the internal combustion engine via a drive belt 5 is coupled. An engine control module (ECM) 7 controls the fuel supply and the operation of the internal combustion engine 1 , A hybrid control module (HCM) receives information about the operating state of the motor vehicle (the related information sources or sensors are not shown) and sends a corresponding command signal to the motor control module 7 to interrupt the fuel supply when the internal combustion engine 1 should be turned off. The hybrid control module 6 Also sends a command signal to the belt-driven integrated starter generator 2 to start the engine and to the engine control module 7 to resume fuel delivery when the internal combustion engine 1 should be restarted.

Since, according to the current regulations, each motor vehicle intended for road use is equipped with a speedometer, each motor vehicle has a mechanism for measuring the rotational speed of one or all of the wheels in contact with the road surface. In modern motor vehicles equipped with an anti-lock braking system, the rotational speed of all wheels is controlled by an ABS control unit 8th determined. From this, the vehicle speed is determined. The active radius of the wheels present on the vehicle is known, so that by means of the ABS control unit 8th both the driving speed of the motor vehicle (in km per hour) and the distance traveled by the vehicle (in km) can be calculated. The covered route is therefore accessible by default and is transmitted via the CAN bus to the hybrid control module 6 transmitted.

• a) Nahezu jedes Fahrzeug ist mit einer digitalen Uhr ausgestattet, welche auch bei abgestelltem Fahrzeug weiterläuft. Eine solche Uhr kann um einen einfachen Zähler für die Anzahl von Tagen seit der ersten Inbetriebnahme des Kraftfahrzeugs erweitert werden, indem der Zählwert des Zählers für jeden Kalendertag um 1 inkrementiert wird. Hierzu ist nicht notwendigerweise die Kenntnis des jeweiligen Datums erforderlich, da der Zähler lediglich vom Zählwert Null bis zum Zählwert 4096 zu zählen braucht und dann wieder auf Null gesetzt werden kann (entsprechend einem 12-Bit-Zähler für 11.2 Kalenderjahre). Dieser Zähler ist an den CAN-Bus anzuschließen, so dass der Zählwert an das Motorsteuerungsmodul 7 übermittelt werden kann.
• b) Die Zeitmessvorrichtung 9 kann auch in diversen elektronischen Steuerungsmodulen implementiert sein, wobei sie unabhängig von dem Betriebszustand des Kraftfahrzeuges eine Zeitmessung vornehmen kann.
• c) Die in vielen Fahrzeugen standardmäßig vorgesehenen Rundfunkempfänger sind häufig bereits an den CAN-Bus angeschlossen, um eine Anpassung des Rundfunkempfängers an den Betriebszustand (z. B. geschwindigkeitsabhängige Lautstärkenregelung, Integrierung einer Freisprechanlage etc.) zu ermöglichen, z. B. bei FM-Receivern mit RDS ("radio data system"), Empfängern für digitalen Rundfunk (DAB = "digital audio broadcasting"), Empfängern für weltweiten Digitalrundfunk (DRM = "digital radio mondial") etc. Sämtliche der vorstehend genannten modernen Rundfunkempfänger empfangen digital aufbereitete Information, welche bereits eine Zeitinformation bzw. einen "Zeitstempel" (Uhrzeit und Datum) enthält, die von dem Rundfunksender bereitgestellt wird. Diese Zeitinformation kann über den CAN-Bus an das Hybrid-Steuerungsmodul 6 übermittelt werden.
• d) Viele Fahrzeuge sind auch mit einem Navigationssystem ausgestattet. Navigationssysteme ermitteln ihre aktuelle Position basierend auf dem Empfang einer Mehrzahl hochpräziser Zeitsignale von einer Gruppe von Satelliten des GPS-, des Glonass- oder (künftig) des Gallileo-Systems. Diese Signale können weltweit empfangen werden. Navigationssysteme sind an den CAN-Bus angeschlossen, um deren Anpassung an die aktuelle Nutzung des Kraftfahrzeuges zu ermöglichen (geschwindigkeitsabhängige Lautstärkeregelung, Integrierung einer Freisprechanlage etc.). Die entsprechende Zeitinformation ist somit verfügbar und kann über den CAN-Bus an das Hybrid-Steuerungsmodul 6 übermittelt werden.

The control arrangement according to the invention further comprises a timing device 9 on, which counts the number of calendar days since the first commissioning of the motor vehicle, regardless of whether the motor vehicle is actually driven or parked unused. For the realization of the timing device 9 For example, you have the following options:

• a) Almost every vehicle is equipped with a digital clock, which continues to run even when the vehicle is parked. Such a watch may be extended by a simple counter for the number of days since the first start-up of the motor vehicle by incrementing the count of the counter by one for each calendar day. Knowledge of the particular date is not necessarily required for this because the counter only needs to count from count zero to count 4096 and then reset to zero (corresponding to a 12-bit counter for 11.2 calendar years). This counter is to be connected to the CAN bus so that the count value is sent to the engine control module 7 can be transmitted.
• b) The timing device 9 can also be implemented in various electronic control modules, where they can make a time measurement regardless of the operating condition of the motor vehicle.
• c) The standard in many vehicles Frequently, radio receivers are already connected to the CAN bus in order to allow the radio receiver to adapt to the operating state (eg speed-dependent volume control, integration of a hands-free system, etc.). B. for FM receivers with RDS ("radio data system"), receivers for digital broadcasting (DAB = "digital audio broadcasting"), receivers for worldwide digital broadcasting (DRM = "digital radio mondial"), etc. All of the above modern Broadcast receivers receive digitally prepared information which already contains a time information or "time stamp" (time and date) provided by the broadcasting station. This time information can be sent via the CAN bus to the hybrid control module 6 be transmitted.
• d) Many vehicles are also equipped with a navigation system. Navigation systems determine their current position based on the receipt of a plurality of high-precision time signals from a group of satellites of the GPS, Glonass, or (in the future) Gallileo system. These signals can be received worldwide. Navigation systems are connected to the CAN bus to allow their adaptation to the current use of the motor vehicle (speed-dependent volume control, integration of a hands-free system, etc.). The corresponding time information is thus available and can be sent via the CAN bus to the hybrid control module 6 be transmitted.

In summary is in the case of the preferred application of the invention to the operation of a Start-stop system the number of reboots of the Internal combustion engine depending on the whole from the motor vehicle covered route as well as from the operating life of the vehicle (eg the number of calendar days, that have elapsed since the vehicle was first used). The values obtained in this case are calculated with the vehicle manufacturer's total operating time compared. When the number of reboots per unit for the distance traveled or exceeds a predetermined threshold per unit time of operation, becomes a delay period for the shutdown of the internal combustion engine (ESD parameters) and set to the sentence of vehicle operating conditions added at a shutdown of the engine must be met. So if normally, d. H. according to the rest current vehicle operating conditions, a shutdown of the engine should take place, the control device holds the on state of the Internal combustion engine for a characterized by the ESD parameter Duration upright. The internal combustion engine is only switched off when the time period characterized by the ESD parameter has expired is and the vehicle operating conditions for the shutdown of the internal combustion engine are still satisfied (i.e. have logical value "true").

there is inventively the length of the period of time characterized as a function of the ESD parameter controlled by a behavior pattern of the driver or vehicle. This allows the control system to be adjusted so that ultimately reached the number of restart operations to the desired or the lifetime of the vehicle manufacturer Vehicle adapted and premature wear of the respective motor vehicle system (eg the start-stop system) compared with the overall system "motor vehicle" is reduced.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - US 2004/0206325 A1 [0002, 0004]
• US 6987330 B2 [0002, 0004]
• - US 6664651 B1 [0003]

Claims (8)

A method for operating a motor vehicle system, said motor vehicle system is operated repeatedly during operation of the motor vehicle by performing at least one function of the motor vehicle system, characterized in that the method comprises the steps of: detecting at least one of the wear of the motor vehicle influencing variable; and varying the frequency with which the function of the motor vehicle system is carried out as a function of the detected variable influencing the wear of the motor vehicle. Method according to claim 1, characterized, that the step of varying the frequency following step includes: Varying the value of a delay period in Depending on the detected, the wear of the Motor vehicle influencing size, the Execution of the function of the motor vehicle system only when exceeded this delay period takes place. Method according to claim 2, characterized in that that varying the value of the delay period depending on at least one of the driving behavior of the motor vehicle characteristic size is done. Method according to one of the preceding claims, characterized in that varying the frequency, executed with the function of the motor vehicle system is, depending on a value determined for the driving behavior of the motor vehicle characteristic size either based on the distance traveled by the vehicle Travel distance or based on the operating time of the vehicle takes place. Method according to one of claims 2 to 4, characterized in that for the delay period only a value greater than zero is selected will, if previously found to be fulfilling one on the frequency of execution of the function of the motor vehicle system related criterion for the expected life expectancy of the motor vehicle earlier is as - the fulfillment of one of the the motor vehicle covered route related criterion for the expected life of the motor vehicle and / or - the Fulfillment of the operating life of the motor vehicle related criterion for the expected service life of the motor vehicle. Method according to one of claims 2 to 5, characterized in that the motor vehicle system is a start-stop system for temporarily switching off an internal combustion engine of Motor vehicle is, with this shutdown only when exceeded the delay period takes place. Method according to claims 5 and 6, characterized in that that by the on the frequency of execution the function of the motor vehicle system related criterion for the expected life of the motor vehicle an upper limit for the number of performed in the operation of the motor vehicle Stop-start operations is described. Device for operating a motor vehicle system, characterized in that it is adapted to a method after one of the previous steps.