DE102020126900A1 - Method for detecting an oil condition of an operating oil, open-loop and closed-loop control device and internal combustion engine - Google Patents

Abstract

The invention relates to a method for detecting an oil condition of an operating oil in an engine (101) of an internal combustion engine (100), in particular for a diesel, Otto or gas engine, the internal combustion engine having: - an oil control system (104) with an oil filter (1F ) for the operating oil (1B) and an oil differential pressure measuring device (IM) designed to detect an oil pressure difference (Δpi) or the like oil pressure relation of the operating oil via the oil filter (1F) in the oil control system (104), - a control and/or control device (10), in particular for controlling and regulating the internal combustion engine, with an analysis module (10.2) for the oil differential pressure (Δpi), wherein- the oil differential pressure (Δpi) in relation to an operating time (hB) of the internal combustion engine is processed in the analysis module (10.2).According to the invention, it is provided that a number of the oil differential pressure (Δpi) taking into account relation variable values (R1, R2, R3,.., Ri) in relation to a number of operating time points in time (hi) is specified, and- the number of relational values (R1, R2, R3,.., Ri) is assigned to a trend development (E) over the operating time points (hi), and- for another to the number of operating times - points in time (hi) adjoining operating time point (hi) a further relation variable value (Ri+1) in relation to a trend deviation (ΔT) from the trend development (E) caused by means of at least one further relation variable value (Ri+1) is analyzed, in particular by means of a changed trend development.

Description

The invention relates to a method for detecting an oil condition of an operating oil in an engine of an internal combustion engine according to the preamble of claim 1. The invention also relates to a control and regulating device and a corresponding internal combustion engine with the control and regulating device.

A method for detecting an oil condition of an operating oil for an engine of an internal combustion engine, in particular for a diesel, Otto or gas engine, is generally known as such.

However, a change in the condition of the operating oil based on significant effects cannot necessarily be determined by oil level sensors alone. One reason is that, for example, an increase in volume as a result of diesel fuel entering the oil circuit competes with oil consumption. In addition, level sensors are associated with additional costs. However, it was recognized that oil quality is of particular importance for the service life of an engine and should basically be based on the principle of oil differential pressure measurement.

For this purpose, an internal combustion engine has: an oil supply system comprising an oil filter for the operating oil and an oil differential pressure measuring device, in particular with a first pressure sensor arranged upstream of the oil filter in the direction of flow and a second pressure sensor arranged downstream of the oil filter in the direction of flow, designed to detect an oil pressure Difference or similar oil pressure relation of the operating oil via the oil filter in the oil supply system.

An oil differential pressure measuring device has in particular a first pressure sensor arranged upstream of the oil filter in the direction of flow and a second pressure sensor arranged downstream of the oil filter in the direction of flow. A first oil pressure upstream of the oil filter can thus be detected and/or specified using the first pressure sensor and a second oil pressure downstream of the oil filter using the second pressure sensor, in order to form the oil pressure difference therefrom. An oil differential pressure measuring device can also be implemented, for example, as part of a maximum oil pressure regulation and/or with an override valve. In particular, this could replace a pressure sensor if one could assume one of the two pressure values to be constant.

An internal combustion engine mentioned at the outset also has a control and/or regulating device known per se, with an analysis module for the differential oil pressure or similar oil pressure relation, the differential oil pressure or similar oil pressure relation across the oil filter in relation to an operating period the internal combustion engine is processed in the analysis module.

Such a method for detecting an oil condition of an operating oil for an engine of an internal combustion engine is known in principle from DE 35 19 026 . To determine the oil filter and oil change time of an internal combustion engine, this method provides an oil pressure sensor before and after the oil filter, with an oil temperature measuring device, an engine speed measuring device and a logic switching element also being provided. The logic switching element emits an output signal when a threshold switch for a certain pressure drop across the oil filter, ie measured by a certain difference in the oil pressure sensor, produces an output signal and at the same time a certain oil temperature and a certain engine speed are present. In this way, it is possible to identify an oil filter and oil change point in time. This theory assumes that the pressure drop across the oil filter increases with the period of use, and that the pressure drop can vary greatly under normal operating conditions, so that the pressure drop can only be within a certain speed and temperature range. The reliability of this teaching is problematic because the pressure drop can vary greatly under normal operating conditions. In addition, the method is comparatively complex because a special operating point is to be determined to determine whether the internal combustion engine is within the limited operating range.

It is desirable to be able to detect an oil condition of an operating oil independently of an operating point specification of this type, and at the same time to be able to avoid excessive fluctuations in statements about the oil condition.

DE 10 2007 048 182 B3 proposes a method of detecting an oil condition with a differential pressure measurement in the oil considering the oil temperature, the engine speed and the like. This theory assumes that the pressure drop in the oil depends on the viscosity of the oil at a given oil temperature and speed. A comparison of the determined pressure difference with a specified reference value for the pressure difference is therefore only carried out when the oil temperature and speed are comparable. However, since the oil filter naturally also changes its flow resistance by filtering out wear particles and/or combustion residues and so according to the teaching of DE 10 2007 048 182 B3 could give a wrong picture of the cause of the increase in flow resistance, the pressure difference is determined mung in DE 10 2007 048 182 B3 explicitly in an oil gallery or in an oil gallery without an oil filter.

It is nevertheless desirable to take into account synergies of an oil filter and oil condition determination when detecting an oil condition based on an oil differential pressure measurement.

This is where the invention comes in, the object of which is to specify a method and a device for detecting an oil condition of an operating oil in an engine of an internal combustion engine and a control and regulating device and an internal combustion engine, by means of which at least one of the above-mentioned aspects is taken into account in particular can be improved. The method and the device should preferably avoid the problems known in the prior art when detecting an oil condition in an improved manner.

The object of the present invention is primarily to specify a method and a device for detecting an oil condition, which uses a detection of an oil pressure difference or similar oil pressure relation of the operating oil via the oil filter in the oil supply system. In particular, this should be done in a way that is improved compared to the prior art. In particular, it should be possible to record and obtain information about the oil condition that is largely independent of the operating condition of an engine.

With regard to the method, this object is achieved by a method according to claim 1 .

• - ein Ölleitsystem mit einem Ölfilter für das Betriebsöl und eine Öl-Differenzdruck-Messeinrichtung ausgebildet zum Erfassen einer Öldruck-Differenz oder dergleichen Öldruck-Relation des Betriebsöls im Ölleitsystem über den Ölfilter,- eine Steuer- und/oder Regeleinrichtung, insbesondere zum Steuern und Regeln der Brennkraftmaschine, mit einem Analysemodul für den Öl-Differenzdruck oder dergleichen Öldruck-Relation, wobei
• - der Öl-Differenzdruck oder dergleichen Öldruck-Relation über den Ölfilter in Bezug auf eine Betriebsdauer der Brennkraftmaschine in dem Analysemodul verarbeitet wird.

In order to detect an oil condition of an operating oil in an engine of an internal combustion engine, in particular for a diesel, Otto or gas engine, the invention assumes that the internal combustion engine has the following features:

• - an oil control system with an oil filter for the operating oil and an oil differential pressure measuring device designed to detect an oil pressure difference or similar oil pressure relation of the operating oil in the oil control system via the oil filter, - a control and/or regulating device, in particular for controlling and regulating the internal combustion engine, with an analysis module for the oil differential pressure or the like oil pressure relation, wherein
• - The oil differential pressure or the like oil pressure relation across the oil filter in relation to an operating time of the internal combustion engine is processed in the analysis module.

According to the invention, it is provided that a number of relation variable values taking into account the oil differential pressure or a similar oil pressure relation is specified in relation to a number of operating time points in time. A relation variable value for a differential oil pressure referred to in this way is to be understood first of all in general as a value which expresses the differential oil pressure as a relation of the oil pressure upstream and downstream of the filter; i.e. this can be a difference, a quotient or some other relation that relates the oil pressure before and after the filter; i.e. assigns a quantitative value to the oil pressure relation. A corresponding relation variable value can preferably be specified in relation to a number of operating time points in time.

The invention has also recognized that the number of relational variable values can be assigned to a trend development over the operating time points in time. In this respect, a trend development is to be understood in principle as any recognizable, in particular analytically describable, indication of a development of the relational values over the operating time points, in particular a possibly computationally interpolated or otherwise comprehensible mathematical indication of a development of the relational values over the operating time. times.

For this purpose, it can be mentioned, in a non-limiting manner, by way of example, that a trend development over the operating time points in time can include the indication of an interpolating compensation curve for the relation variable values for a differential oil pressure over the operating time points in time; for example, as a regression line based on the least squares method. In particular, a trend can include the specification of a slope of the interpolating compensation curve, preferably include the specification of a regression line, or a trend development can include specification of an interpolating—and possibly extrapolating—compensation curve, preferably a regression line.

It has been shown within the scope of a development already to be mentioned here that a trend development up to a specific point in time during operation can be referred to as a normal trend development. In the present case, a normal trend development of an oil differential pressure is to be understood first of all in general as any expected trend development of an oil differential pressure across an oil filter of a specific engine, which proceeds without a recognizable change in the condition of the oil in the narrower sense or without one that needs to be taken into account.

In addition, the invention is now based on the consideration that a significant effect of a change in the condition of the oil results in a change in viscosity; and according to knowledge of the invention a reduction in viscosity. As will be explained, a reduction in viscosity can result from oil dilution as well as oil aging. Both effects are superimposed on every trend development, in particular with increasing operating time also on a normal trend development to an increasing extent and, according to the knowledge of the invention, they are therefore recognizable in comparison to this. In addition, both effects can be seen in the context of an oil pressure difference or similar oil pressure relation of the operating oil via the oil filter in the oil supply system, even compared to a filter change; a filter change does result in a reduction in the oil pressure difference, but a comparatively sudden reduction in the oil pressure difference compared to all other changes.

The invention is also based on the groundbreaking idea that the aforementioned type of significant effects of a change in the condition of the oil -- in particular based on oil dilution and oil aging -- can nevertheless be measured by means of a differential pressure across an oil filter, especially if they are superimposed on a normal trend development of an oil differential pressure. In both cases of oil dilution as well as oil aging, there is a reduction in viscosity, which is therefore generally recognizable as a reduction in an oil pressure difference. However, such a detection is made using a more reliable approach according to the invention, which is different and improved compared to prior art concepts. The appropriate assignment of a number of relational variable values to a trend development over the operating time points has proven to be superior to the prior art.

Thus, the invention initially recognized that as part of oil aging, the viscosity should essentially decrease over time, since the long-chain hydrocarbon chains are broken up by mechanical shearing forces. In the course of oil dilution, the viscosity should also decrease, but due to different processes on a different time scale. In the case of oil dilution, there is also a differential pressure loss as a contribution to the trend, which shows a downward development compared to a previous trend development and in particular compared to a normal trend development up to a specific operating time.

The invention has accordingly also recognized that for a further operating time point in time that is added to the number of operating time points, a further relation variable value is analyzed very generally with regard to a relevant trend deviation caused by at least one further relation variable value by means of a changed trend development .

In concrete terms, the invention has recognized that, regardless of the type of engine, such as a diesel, Otto or gas engine, a relevant trend deviation from the trend development can be analyzed using a trend development that has already changed, in particular in comparison to a normal trend development a specific operating time.

For example, a relevant trend deviation, in particular a trend deviation from a normal trend development, as a result of a changed trend development can preferably be recognized in a significant change in the above-mentioned compensation curve using the at least one further relation variable value. Merely as a non-limiting example, it should be mentioned that a trend deviation can include, for example, an indication of a change in slope of the regression curve, preferably a regression line, if a new relational value over a new operating time point in time is added to the existing set of relational values. Such a significant change in the above-mentioned compensating curve by means of the at least one further relation variable value is not limited to a change in slope, it can also be recognized in principle in a change in curvature. Above all, however, it is not exclusively dependent on a decrease in an amplitude. Rather, the invention has recognized that in general the detection by means of a changed trend development in comparison to a previous trend development--so to speak, in comparison to an engine-specific history--in any case significant oil changes such as oil aging or oil aging can be identified might.

Furthermore, the invention relates to a control and regulating device according to claim 20 and an internal combustion engine according to claim 24.

The control and/or regulating device for controlling and/or regulating an internal combustion engine is designed to detect an oil condition of an operating oil for an engine of the internal combustion engine, in particular for a diesel, Otto or gas engine, to carry out and has a method according to the concept of the invention an analysis module for an oil differential pressure.

The analysis module is designed, in particular, to relate the first and second oil pressure by means of a relation variable that takes them into account to process the operating time of the internal combustion engine and to carry out the steps of the method according to the invention.

The internal combustion engine has an oil control system comprising an oil filter for the operating oil and an oil differential pressure measuring device, in particular with a first pressure sensor arranged upstream of the oil filter in the direction of flow and a second pressure sensor arranged downstream of the oil filter in the direction of flow, which are designed to detect and indicate a first oil pressure before the oil filter by means of the first pressure sensor and a second oil pressure after the oil filter by means of the second pressure sensor, the internal combustion engine also having a control and/or regulating device based on the concept of the invention.

In summary, the invention has fundamentally recognized that measuring the oil differential pressure has particular advantages in addition to the above-mentioned significant effects, especially via a filter, if significant effects of a change in the condition of the oil --in particular from oil dilution and/or oil aging-- be assessed as a result of insights into the change in viscosity. The invention has thus recognized for the first time that relevant oil state changes of this type are based on a reduction in viscosity and are nevertheless generally recognizable as changes in the trend with a proper trend analysis, i.e. by means of a changed trend development compared to a previous trend development.

Advantageous developments of the invention can be found in the subclaims and specify advantageous possibilities in detail for realizing the concept explained above within the scope of the task and with regard to further advantages.

According to the finding of a particularly preferred development of the invention, relevant oil state changes of this type are generally recognizable as a change to the trend and specifically as part of a decreasing trend deviation; i.e. recognizable as a decrease in trend development for an oil pressure difference or similar oil pressure relation of the operating oil via the oil filter in the oil control system. In particular for a diesel or Otto engine, the development has shown that a decreasing oil pressure difference or a similar oil pressure relationship can be clearly identified in a trend development with the procedure proposed by the invention. A decrease in the trend development for an oil pressure difference or a similar oil pressure relation primarily means a decrease in amplitude.

The original purpose of monitoring the oil filter differential pressure can also be used to advantage when replacing a filter. In particular, in addition to monitoring the condition of the oil, a determination of the condition relating to oil dilution and/or oil aging can be detected. Advantageously, however, the method for detecting an oil condition is not only limited to determining an oil pressure difference or a similar oil pressure relationship for determining oil dilution or oil aging; an intelligent evaluation of this oil pressure difference or a similar oil pressure relation can advantageously take place.

The oil pressure difference determined via a filter or a similar oil pressure relation, in particular a measured first and second oil pressure value, is advantageously converted to a relation variable value independent of the operating parameter. A relation variable value that is independent of an operating parameter can preferably be specified in relation to a number of operating duration points in time. The operating parameters include, in particular, oil temperature and engine speed. A number of such operating parameters of independent relational values can be formulated independently of the operating parameters of oil temperature and engine speed, and operating parameters can be specified independently in relation to a number of operating time points in time.

In particular, such a normal trend development can -possibly. as can be seen, depending on the engine, as a basic standard. A comparison can be made with such a normal trend development for a further operating time point in time that is added to the number of operating time points; namely in order to determine a relevant trend deviation from the trend development that has been present up to that point, i.e. in particular to determine the trend development referred to as normal trend development, caused by means of the at least one further relation variable value.

Within the framework of a further development already mentioned, a certain normal trend development can advantageously be assumed under certain conditions; e.g. if one assumes the behavior of an engine that does not show any change in the condition of the oil in the narrower sense.

In a first variant of a development, for example primarily in a diesel or Otto engine, an increasing trend in the behavior of an oil differential pressure or similar oil pressure relation can be assumed and in a second variant of a further development - for example primarily in a gas engine a constant or decreasing trend of an oil differential pressure or similar oil pressure relation can be assumed. Both variants are explained below.

A preferred development provides, for example, that a standard map of standard differential pressures --comprehensively considering oil pressure, relational variables based on "normal differential pressures" (preferably a healthy engine with new oil and new filter or according to another gold standard) as a function of oil temperature and speed is available. Such a standard characteristics map of standard differential pressures can be learned, for example, on a test stand for a specific engine type and can be available in a controller for each engine of the engine type.

An operating parameter-independent relational variable value can also be obtained when the engine is operated in the field if this relational variable value --or advantageously the oil pressure values themselves used for this purpose-- are converted via oil parameters and/or engine parameters to a value that is independent of the The operating point is, in particular, independent of an oil parameter and/or engine parameter. In one way or another, a relation variable value can be specified which, as a standardized oil differential pressure, eliminates those operating parameters for which the oil differential pressure was measured - the independent relation variable value is then considered to be independent of the operating parameter.

In order to eliminate the influence of an operating point, for example, a relational variable value at a specific oil temperature and speed can be divided by the associated standard differential pressure of the standard map and thus viewed as an operating parameter-independent relational variable value. In order to eliminate the influence of an operating point, in one variant, for example, the oil pressure values used for the relational variable value can be divided by the associated standard oil pressure value of a standard map even at a specific oil temperature and speed; An operating parameter-independent relative variable value can then be formed from these normalized or operating parameter-independent oil pressure values by difference or quotient formation or otherwise. One or the other procedure can be appropriately selected depending on the circumstances. In particular, a standard characteristics map can be used advantageously; but this is not mandatory. For example, a mining engine is only operated at comparatively few operating points, e.g. at one to three operating points; these can also be recorded without a standard characteristic map in such a way that an operating parameter independent of a relation variable value can be formulated for the analysis of the oil pressures or oil differential pressures for trend development. A fracking engine, on the other hand, has a comparatively wide range of operating points, so that it makes sense to record a standard characteristic map of standard pressures or standard differential pressures for a standard engine and/or standard operating oil.

In any case, a complicated selection of only comparable values for a specific oil temperature and for a specific speed, which is required in the prior art, can thus be omitted if work is carried out directly with a relation variable value that is independent of the operating parameter. A trend development is then preferably to be understood in principle as any type of indication of the operating parameter-independent relation variable over operating time points in time. This can include a straight regression line based on the least squares error method, which occurs, for example, in the form of a curve or straight line, interpolating or extrapolating, taking into account the determined relation variable values.

In this development in particular with an operating parameter-independent relation variable value, it has been recognized that for each additional operating point in time that is added to the number, a further operating parameter-independent relation variable value can be analyzed with regard to a trend deviation of the further relation variable value from the trend development. This type of analysis has proven to be particularly advantageous because it is comparatively efficient and independent of fluctuations - overall, the method according to the concept of the invention thus has a significantly improved resistance to fluctuations in the measurement range and the accuracy of the method according to the invention is therefore superior to other known methods.

As already mentioned above, within the framework of a further development, a certain normal trend development can advantageously be assumed under certain conditions; e.g. if one assumes the behavior of an engine that does not show any change in the condition of the oil in the narrower sense. In a first variant of a development, for example primarily in a diesel or Otto engine, an increasing trend in the behavior of an oil differential pressure or similar oil pressure relation can be assumed and in a second variant of a further development - for example primarily in the case of a gas engine, a constant or decreasing trend in an oil differential pressure or similar oil pressure relation can be assumed. Both variants are explained below.

According to a first development within the scope of a filter model assumed as an example, a trend that is basically increasing according to the first variant of a normal trend development weakens as a result of oil dilution, at least with an increasing relation variable taking into account the first and second oil pressure. A trend deviation between the further relation variable value from the trend development can then be evaluated in different ways; a trend deviation can be advantageously analyzed as part of an assessment of short-term or long-term trend development.

A further development, for example in the aforementioned first preferred variant, is based on the consideration that—as in the prior art mentioned at the outset with a differential oil pressure in relation to an operating time—a relation variable value assigned to the differential oil pressure tends to increase in principle is (first variant of a normal trend development), in particular monotonously increasing over the operating period; This normal trend development has generally been confirmed in a diesel or Otto engine as a first preferred variant, since the development of soot inherent in operation there tends to be responsible for the oil filter becoming clogged with soot particles over the period of operation.

It is therefore advantageously provided that in the aforementioned first preferred variant of a development, there is an assumption to the effect that a trend development in the form of a normal trend development over the operating period is generally increasing overall, in particular monotonically increasing. This means that the development assumes that in the normal case of normal operation of the engine, the beginning of a trend development of an oil differential pressure in relation to an operating time in the form of a normal trend development is increasing, in particular is monotonically increasing over the operating time.

This statement takes into account the fact that in the first variant of a preferred development, the filter slowly becomes clogged over time; the relevant trend deviation from the trend development is therefore in particular superimposed on a normal trend development, which normal trend development, however, only reflects the effect of the filter. The relevant trend deviation is therefore additionally superimposed, above all on the t effect of the filter. With increasing load, the differential pressure logically increases - this is a slow trend. With increasing load, the differential pressure increases as part of a slow trend, i.e. a monotonically increasing normal trend development over a long time scale (such as a few 1000 operating hours).

Within the scope of a particularly preferred development, the relevant trend deviation results from a changed trend development generally as a decrease from the previous trend development, insofar as a decreasing trend deviation from the previous or current trend development, in particular a normal trend development.

The trend deviation from the previous trend development can be seen as a decrease from the fact that the further relational value is below the current trend development or previous trend curve, and/or the slope of a relevant trend development, in particular another trend curve, decreases with the further relational value. The relevant trend deviation particularly preferably results as a trend development that decreases below an increasing normal trend development. Even in the case of the first variant of an increasing normal trend development and the case of a second variant of a constant or decreasing normal trend development, the trend deviation can be recognized as a decrease from the fact that the further relational value is below the current trend development or previous trend curve; i.e. preferably below the increasing normal trend development or below the constant or decreasing normal trend development.

According to a preferred development, the further relation variable value is analyzed in relation to a decreasing trend deviation from the trend development caused by at least one further relation variable value as the relevant trend deviation. The trend deviation then results from a decrease in relation to the existing trend, in particular in comparison to the aforementioned normal trend development up to a certain point in time during operation.

According to the aforementioned first variant of an increasing normal trend development of the oil differential pressure, for example in a diesel or Otto engine, this corresponds to a decrease in the trend development - the changed trend development increases less sharply in comparison to the increasing normal trend development or even falls; in the case of a regression curve, this may be the detection of a positive slope value decreasing compared to that of the increasing normal trend, or reversing to a negative slope value of the changed trend compared to the positive slope value of the increasing normal trend. However, it was nevertheless recognized that the approach of a normal trend development of an oil differential pressure in relation to an operating time can only be established in a first variant, albeit a particularly preferred one, as a fundamentally increasing trend. In particular, a monotonous increase in the differential pressure does not occur in a gas engine, for example, since it produces little or no soot. A further development, for example, in a second preferred variant, is based on the consideration that a relation variable value assigned to the oil differential pressure tends to remain the same or only slightly increases or possibly even falls (second variant of a normal trend development), in particular is decreasing over the operating time. In the case of a compensating curve, this can be the detection of a positive or negative slope value around zero or clearly in the negative range.

A relevant trend deviation from the trend development can therefore not only be analyzed as a trend deviation by means of a tendential decrease in the existing trend development (according to the aforementioned first variant, for example in a diesel or Otto engine). It can also be seen from an increased trend development (according to the second variant mentioned above) in the sense that a previous or current trend development that has remained the same or is already declining (e.g. in the case of a gas engine) is further intensified with a further decrease or decreasing trend deviation. This means that the deviation from the trend results from an increase in the previous trend development; in the sense of an increase compared to the current trend development, in particular in comparison to the aforementioned normal trend development up to a certain operating time, which (e.g. in the case of a gas engine) can already represent a decreasing trend development in accordance with the aforementioned second variant. In the case of a best fit curve, this may be the detection of an increasing negative slope value around zero or even more negative than before; overall with an increasing negative slope value.

In this case, too, a sudden change can be used to identify a filter change; since there is hardly any soot in the gas engine, the filter clogs up much less and an increasing jump in the trend development can also be recognized as a filter change.

Independently, additionally or alternatively, a particularly preferred development provides that the two aforementioned relevant effects of oil aging and oil dilution can be recognized and differentiated on the basis of the speed of the trend deviation from a current or previous trend development. In a particularly preferred development, the concept of the invention also offers the basis, in particular between a sudden, a fast and a slow trend development, in particular independently of a previous or current trend development or normal trend development and/or independent of an amplitude of a changed trend development distinguish trends.

• 1. eine Öl-Alterung, welche als eine abnehmende Trendabweichung auf längerer Zeitskala (zeitlich global) erkennbar ist,
• 2. eine Öl-Verdünnung, welche ebenfalls als eine abnehmende Trendabweichung (zeitlich global) erkennbar ist; mit Vorteil versehen aber auf deutlich kürzerer Zeitskala im Vergleich zu der vorgenannten längeren Zeitskala der Öl-Alterung,
• 3. Eine starke (zeitlich lokal) zeitlich beschränkte Steigungsänderung bedeutet regelmäßig einen Filtertausch. Ein Filtertausch, der also eine insofern vergleichsweise plötzliche, insbesondere zunehmende Trendabweichung zur Folge hat, erfolgt also auf sehr kurzer Zeitskala (praktisch instantan). Ein Filtertausch ist als praktisch instantane Trendabweichung erkennbar im Vergleich zu der vorgenannten kürzeren Zeitskala der Öl-Verdünnung. Während die beiden ersten Effekte einer Öl-Alterung und einer Öl-Verdünnung zu einer Verringerung der Viskosität führen, liegt der Unterschied bei diesen also in der Stärke, mit anderen Worten „Geschwindigkeit“, Rampe oder Steigung des Trends. D.h. während eine Viskositätsänderung bei einem normalen Motorbetrieb über hunderte von Stunden einer Betriebsdauer beobachtbar ist, tritt die Viskositätsänderung durch Öl-Verdünnung innerhalb weniger Stunden einer Betriebsdauer auf und ein Filtertausch ist in Bezug auf eine Gesamtskala einer Betriebsdauer im Vergleich dazu praktisch instantan.
• Ein Filtertausch wird jedenfalls bei einer vorgenannten ersten Variante (etwa bei einem Diesel- oder Otto-Motor) -regelmäßig aufgrund eines Tausches eines rußbeladenen Filters gegen einen freien Filter mit einer praktisch instantanen Abnahme der ÖlDruckdifferenz verbunden sein. Dies ist nicht notwendiger Weise der Fall bei einer vorgenannten zweiten Variante (etwa bei einem Gas-Motor), - regelmäßig liegt dort kein Tausch eines rußbeladenen Filters vor; gleichwohl kann es sich jedoch um einen zugesetzten Filter beim Tausch handeln.

As part of a further development, it was advantageously recognized that, when analyzing a relevant decreasing trend deviation from the current or previous trend development, three superimposed effects in particular must be taken into account. The training has recognized that the causes of a decreasing trend deviation can be:

• 1. oil aging, which is recognizable as a decreasing trend deviation on a longer time scale (global in time),
• 2. Oil dilution, which is also evident as a decreasing trend deviation (global in time); beneficial but on a significantly shorter timescale compared to the aforementioned longer timescale of oil aging,
• 3. A strong (temporally local) time-limited gradient change means a regular filter change. A filter change, which therefore results in a comparatively sudden, in particular increasing trend deviation, takes place on a very short time scale (practically instantaneously). A filter change is seen as a virtually instantaneous trend deviation compared to the aforementioned shorter time scale of oil dilution. So while the first two effects of oil aging and oil dilution lead to a decrease in viscosity, the difference between these is the magnitude, in other words “speed”, ramp or slope of the trend. That is, while a viscosity change in normal engine operation is observable over hundreds of hours of service, the viscosity change due to oil dilution occurs within a few hours of service and filter replacement is virtually instantaneous on an overall scale of service by comparison.
• In any case, in the first variant mentioned above (e.g. in a diesel or Otto engine), replacing a soot-laden filter with a free filter is usually associated with a practically instantaneous decrease in the oil pressure difference. This is not necessarily the case in an aforementioned second variant (e.g. in a gas engine), - there is usually no replacement of a soot-laden filter; nevertheless, it can be a clogged filter when replacing.

A reset of a trend observation after an oil or filter change has proven to be advantageous; This means that a trend analysis that is global in terms of time is then carried out with a new zero point for the trend analysis, for example with a compensating curve or regression line.

According to a correspondingly preferred development, the further relational variable value is analyzed as the relevant trend deviation in relation to a decreasing trend deviation from the trend development caused by at least one further relational variable value, with a time extension and/or amplitude, in particular Ramp, which is analyzed - especially decreasing - trend deviation from the trend development.

Provision is preferably made for a trend signature of the decreasing trend deviation to be identified as the relevant trend development, for which the time extension, in particular the ramp, has a finite value above zero and up to a maximum of a few hours. In particular, the time extension is above 5 minutes and up to a maximum of ten hours.

On the other hand, there is a sudden change in differential pressure in the form of a sudden increase when the oil is topped up. An oil refill results in an increasing deviation from the trend. When replacing the filter, the differential pressure change occurs as a differential pressure drop; i.e. a decreasing trend deviation suddenly occurs - a subsequent oil refill results in a suddenly increasing trend deviation. In particular, this combination is clearly trending. These effects of an increasing differential pressure change are preferably left out of consideration in a further analysis. However, any jumps in pressure caused by an oil or filter change can be recognized and calculated from the trend (not described in detail here).

A particularly advantageous development of the method, in particular of a control and/or regulating device, relates to determining the oil condition of an operating oil for an engine of an internal combustion engine, in particular for a diesel or gas engine, preferably for detecting oil dilution.

A trend development of the relation variable is advantageously stored with a filter model.

A filter model for the oil filter can be designed in such a way that the processing of the first and second oil pressure takes place using a relation variable that takes the filter model into account in relation to an operating time and/or the operating parameters of the internal combustion engine. In particular, the above-mentioned trends of oil aging, oil dilution and filter replacement can be taken into account in the filter model in such a way that a distinction is made between a slow, faster and sudden trend.

In particular, it is provided that a relevant trend development of the relation variable with regard to oil dilution is discriminated by means of the filter model, in particular as a comparatively rapid but not sudden trend signature.

Advantageously, a trend development of the relation variable can also be stored with a filter model in such a way that when the first and second oil pressures are processed by means of a relation variable that takes them into account in relation to an operating time of the internal combustion engine, a run-in time of the engine during the operating time and/or an oil refill is not taken into account and/or a filter change and, if necessary, an oil refill are followed by a new indication of the trend development. This avoids falsifying run-in times and their relation sizes to the otherwise robust determination of a trend development.

• - eine Einlaufzeit des Motors, wobei eine Trendsignatur einer Einlaufzeit im Trend bei der Betriebsdauer unberücksichtigt bleibt,
• - einen Filtertausch, wobei -gemäß dem oben genannten vierten Effekt-- eine abnehmende Trendsignatur des Filtertauschs im Trend von einer Neu-Angabe der Trendentwicklung gefolgt wird,
• - einer Öl-Alterung, wobei -gemäß dem oben genannten ersten Effekt-- eine abnehmende Trendsignatur der Öl-Alterung im Trend von einer ansteigenden Normal -Trendentwicklung überlagert wird,
• - einer Öl-Nachfüllung, wobei eine Trendsignatur der Öl-Nachfüllung -gemäß dem oben genannten zweiten Effekt-- plötzlich zunehmend oder moderat zunehmend ist.

It is preferably provided that the relevant trend development of the relation variable is discriminated by means of the filter model relating to one or more trend signatures for:

• - a run-in period of the engine, with a trend signature of a run-in period being disregarded in the trend in the service life,
• - a filter exchange, whereby - according to the fourth effect mentioned above -- a decreasing trend signature of the filter exchange in the trend is followed by a new indication of the trend development,
• - oil aging, whereby - according to the first effect mentioned above - a decreasing trend signature of oil aging in the trend is superimposed by an increasing normal trend development,
• - an oil replenishment, wherein a trend signature of the oil replenishment -according to the above second effect-- is suddenly increasing or moderately increasing.

It is advantageously provided that the relational variable takes into account the first and second oil pressure as the oil pressure difference.

The open-loop and/or closed-loop control device advantageously has a map module that is designed to form an oil pressure difference between the second and first oil pressure, in particular for an operating parameter and/or an operating time of the internal combustion engine. Preferably, a number of oil pressure difference values for an operating time for various operating parameters of the internal combustion engine are available in a map via the map module. In this respect, it has proven to be advantageous to generally form at least one oil pressure difference between the second and first oil pressure for each relation variable value at a point in time during the operating period.

In particular, it is provided that an oil pressure difference between the first and second oil pressure for a number of operating parameters of the internal combustion engine, for example engine parameters of the engine and/or oil parameters of the operating oil, is recorded in a characteristic map for the number of operating parameters for an operating time point in time ; such a map can preferably be stored in the map module. The operating parameters of the internal combustion engine preferably include at least an engine speed of the engine and the oil temperature of the operating oil.

The characteristic map is preferably created for a standard engine and/or a standard operating oil. In this respect, the characteristics map can define a normalization standard for a standard engine and/or a standard operating oil. Different standards can also be defined that are specific to a certain engine type. For example, a standard for a few typically few operating points can be defined for a mining engine; on the other hand, a fracking engine will have a relatively "broad" map. Provision is advantageously made for the oil pressure relation, in particular the oil differential pressure, in particular a first and second oil pressure, to be converted into a standardized oil pressure relation, in particular into a standardized differential oil pressure.

For example, a number of oil pressure relations of the second and first oil pressure, in particular the oil differential pressures of the second and first oil pressure, can be formed for each relation variable value at an operating time point and from one oil pressure relation, in particular oil differential pressure normalized relation size value can be formed. Advantageously, the normalized relation variable value can be formed as a quotient from the oil pressure relation, in particular the oil differential pressure, and an associated variable of the characteristic map, in particular a standard variable, for an operating parameter of the engine and/or oil parameter for an operating time point in time .

As part of a preferred development, a normalized relation variable value for an oil pressure difference can be formed using a converter algorithm assigned to the engine for the normalized relation variable value for the operating time point in time have integration.

With regard to the trend deviation between the further relation variable value from the trend development, a distance and/or gradient calculation is advantageously provided, in particular a difference quotient over time, by means of which the trend deviation is evaluated. In addition or as an alternative, it is provided that, in the event of a significant deviation from the trend, a status signal is output that indicates a significantly impaired oil status. This has the advantage that a trend deviation between the further relation variable value from the trend development can first be evaluated quantitatively before an output of a status signal is caused on the basis of this.

A trend deviation between the further relation variable value from the trend development can be evaluated in different ways. In a first modified development, it is particularly advantageous to analyze a short-term trend development in such a way that the trend deviation of the further relation variable value itself is analyzed from the normal trend development present at the time of operation.

In a second modified development, it is particularly advantageous to analyze a long-term trend development in such a way that a trend deviation of a trend development determined with the further relation variable value from the normal trend development present at the time of operation is analyzed.

In addition, it has proven to be advantageous within the framework of a development that an upper and lower limit development is specified for a normal trend development and/or an earlier and later expected time for a status signal. The further development has recognized that the specification of different trend developments at an upper and lower limit of a normal range allows the specification of an expected time to be more reliable.

• - einen Betriebsaufzeichner in dem eine Anzahl den zweiten und den ersten Öldruck berücksichtigende Relationsgrößen-Werte in Bezug auf eine Anzahl von Betriebsdauer-Zeitpunkten angegeben wird,
• - einen Trendbildner mittels dem der Anzahl von Relationsgrößen-Werte eine Trendentwicklung zugeordnet wird,
• - einen Abweichungsbildner mittels dem für einen weiteren zur Anzahl hinzutretenden Betriebsdauer-Zeitpunkt ein weiterer Relationsgrößen-Wert in Bezug auf eine vermittels wenigstens des einen weiteren Relationsgrößen-Wertes bewirkte Trendabweichung von der Trendentwicklung analysiert wird

The control and regulation device advantageously includes an analysis module for the first and second th oil pressure by means of a relational variable that takes this into account in relation to an operating time of the internal combustion engine, which is designed for processing, to convert the first and second oil pressure to an operating parameter-independent relational variable value and has:

• - an operation recorder in which a number of the second and the first oil pressure considering relation variable values are specified in relation to a number of operating duration times,
• - a trend generator by means of which a trend development is assigned to the number of relational values,
• - a deviation generator by means of which a further relation variable value is analyzed in relation to a trend deviation from the trend development caused by at least the one further relation variable value for a further operating time point in time added to the number

The deviation generator is preferably designed to evaluate the trend deviation and/or a signal transmitter is designed to output a status signal, in the event that the trend deviation is significant, which indicates a significantly impaired oil status. A trend deviation can, for example, be evaluated for a regression trend curve of a changed trend development by means of a distance calculation for an amplitude; a trend deviation can also be evaluated additionally or alternatively and on a case-by-case basis depending on the circumstances by means of a difference quotient or differential quotient formation.

• 1 eine bevorzugte Ausführungsform einer Brennkraftmaschine mit vorliegend einem Diesel- oder Gasmotor, umfassend ein Ölleitsystem mit einem Ölfilter und mit einer Öl-Differenzdruck-Messeinrichtung,
• 2 eine Steuer- und Regeleinrichtung mit einer ECU und mit einem Kennfeldmodul und mit einem Analysemodul für die Brennkraftmaschine zur Umsetzung eines Verfahrens zum Erfassen eines Ölzustands eines Betriebsöls für einen Motor der Brennkraftmaschine gemäß einer bevorzugten Ausführungsform;
• 3 für ein Verfahren zum Erfassen eines Ölzustands eines Betriebsöls für einen Motor der Brennkraftmaschine in Ansicht (A) ein erstes Trendfeld T_a und in Ansicht (B) ein zweites Trendfeld T_b, jeweils zur Bestimmung einer Trendabweichung ΔT zwischen einem weiteren Relationsgrößen-Wert und einer bisherigen Trendentwicklung auf unterschiedliche Weise,
• 4 ein Ablaufdiagramm einer bevorzugten Ausführungsform des Verfahrens zum Erfassen eines Ölzustands eines Betriebsöls für einen Motor der Brennkraftmaschine wie in 1 mit einer Steuer- und Regeleinrichtung wie in 2 und unter Berücksichtigung einer Trendentwicklung wie in 3 erläutert;
• 5 eine schematische Darstellung für eine erste bevorzugte Ausführungsform betreffend die Wandlung gemessener Öldrücke zu einem Relationsgrößen-Wert, der unabhängig von einem Betriebsparameter ist, mittels eines Kennfelds und eines Wandleralgorithmus, wobei Relationsgrößen-Werte und eine Trendentwicklung in einem beispielhaften Trenkennfeld T_a über Betriebsdauer-Zeitpunkte dargestellt sind, für ein Verfahren zum Erfassen eines Ölzustands eines Betriebsöls für einen Motor der Brennkraftmaschine;
• 6 eine vergrößerte Darstellung des in 5 gezeigten Trendkennfeldes T_a mit einer vom Betriebsparameter unabhängigen Auftragung von Relationsgrößen-Werte als Δp über Betriebsdauer-Zeitpunkte hi, i=1, 2, 3, sowie eine darauf basierende erste Trendentwicklung als obere Grenzentwicklung und eine zweite Trendentwicklung als untere Grenzentwicklung mit einem entsprechend früher bzw. später angesetzten Erwartungszeitpunkt für ein Zustandssignal;
• 7 eine schematische Darstellung für eine zweite besonders bevorzugte Ausführungsform für ein Verfahren zum Erfassen eines Ölzustands eines Betriebsöls für einen Motor der Brennkraftmaschine, wobei betreffend die Wandlung gemessener Öldrücke zu einem Relationsgrößen-Wert, der einen Betriebsparameter insofern berücksichtigt, dass in einer besonders bevorzugten Vorgehensweise mittels einem normierten Filter-Differenzdruck-Kennfeld T_a der Filter-Differenzdruck normiert wird unter Erstellung eines normierten Filter-Differenzdruck, über die Betriebszeit, wobei Relationsgrößen-Werte als eine Trendentwicklung des normierten Filter-Differenzdrucks in einem beispielhaften Trendkennfeld T_a über Betriebsdauer-Zeitpunkte dargestellt sind;
• 8A zeigt beispielhaft einen konkreten Verlauf eines normierten Öl-Differenzdrucks Δp mit den zuvor genannten normierten Relationsgrößen-Werten Ri einer Trendentwicklung E über die Betriebsdauer h_B einer Brennkraftmaschine mit einem Motor und dem Ölfiltersystem;
• 8B in Ansichten (A) und (B) verschiedene Ausführungsformen von Trendfeldern T_a, T_b zur Bestimmung einer Trendabweichung ΔT zwischen einem weiteren Relationsgrößen-Wert und der Trendentwicklung; vorteilhaft im Rahmen einer in Ansicht (A) dargestellten langfristigen Trendentwicklung Eg zur Ermittlung von Filtertauschprognose oder einer in Ansicht (B) dargestellten kurzfristigen Trendentwicklung zur Erkennung von Öl-Verdünnung —E₁; in Ansicht (C) ist eine bevorzugte Variante zur Berücksichtigung eines Filtertauschs mit einer Filtertauscherkennung für ein Trendfeld, T_c dargestellt.

Embodiments of the invention are now described below with reference to the drawing in comparison to the prior art, some of which is also shown. This is not necessarily intended to represent the embodiments to scale, rather the drawing is in schematic and/or slightly distorted form where it is useful for explanation. With regard to additions to the teachings that can be seen directly from the drawing, reference is made to the relevant state of the art. In this context, it must be taken into account that a wide variety of modifications and changes relating to the form and detail of an embodiment can be made without deviating from the general idea of the invention. The features of the invention disclosed in the description, in the drawing and in the claims can be essential both individually and in any combination for the further development of the invention. In addition, all combinations of at least two of the features disclosed in the description, the drawing and/or the claims fall within the scope of the invention. The general idea of the invention is not limited to the exact form or detail of the preferred embodiment shown and described below, or limited to any subject matter which would be limited compared to the subject matter claimed in the claims. In the case of specified design ranges, values lying within the specified limits should also be disclosed as limit values and be usable and stressable as required. Further advantages, features and details of the invention result from the following description of the preferred embodiments and from the drawing; this shows in:

• 1 a preferred embodiment of an internal combustion engine with a diesel or gas engine in the present case, comprising an oil supply system with an oil filter and with an oil differential pressure measuring device,
• 2 a control and regulating device with an ECU and with a map module and with an analysis module for the internal combustion engine for implementing a method for detecting an oil condition of an operating oil for a motor of the internal combustion engine according to a preferred embodiment;
• 3 for a method for detecting an oil condition of an operating oil for an engine of the internal combustion engine in view (A) a first trend field T _a and in view (B) a second trend field T _b , each for determining a trend deviation ΔT between a further relation variable value and a previous trend development in different ways,
• 4 a flow chart of a preferred embodiment of the method for detecting an oil condition of an operating oil for an engine of the internal combustion engine as in FIG 1 with a control and regulation device as in 2 and taking into account a trend development as in 3 explained;
• 5 a schematic representation for a first preferred embodiment relating to the conversion of measured oil pressures to a relational value, which is independent of an operating parameter, by means of a characteristic map and a converter algorithm, with relational variable values and a trend development in an exemplary Trenkennfeld T _a over operating time points are shown for a method for detecting an oil condition of an operating oil for an engine of the internal combustion engine;
• 6 an enlarged view of the in 5 shown trend map T _a with a plot independent of the operating parameters of relational values as Δp about operating duration times hi, i=1, 2, 3, and a first trend development based thereon as the upper limit development and a second trend development as the lower limit development with a correspondingly earlier or later expected time for a status signal;
• 7 a schematic representation for a second particularly preferred embodiment for a method for detecting an oil condition of an operating oil for an engine of the internal combustion engine, relating to the conversion of measured oil pressures to a relational value that takes into account an operating parameter insofar as in a particularly preferred procedure using a normalized filter differential pressure map T _a, the filter differential pressure is normalized while creating a normalized filter differential pressure over the operating time, with relational values being shown as a trend development of the normalized filter differential pressure in an exemplary trend map T _a over operating time points ;
• 8A shows an example of a specific course of a standardized oil differential pressure Δp with the above-mentioned normalized relational variable values Ri, a trend development E over the operating time h _B of an internal combustion engine with a motor and the oil filter system;
• 8B in views (A) and (B) different embodiments of trend fields T _a , T _b for determining a trend deviation ΔT between a further relation variable value and the trend development; advantageously in the context of a long-term trend development Eg shown in view (A) for determining a filter replacement prognosis or a short-term trend development shown in view (B) for detecting oil dilution —E ₁ ; View (C) shows a preferred variant for considering a filter change with a filter change detection for a trend field, T _c .

1 shows an internal combustion engine 100 with a motor 101 and various structures such as air duct systems 102, including components such as turbochargers or the like, and also heat exchanger 103, including coolers such as an air cooler or an oil cooler. The internal combustion engine also has an oil supply system 104, comprising an oil circuit with the oil cooler (not shown) and an oil pan, in which the operating oil is routed, for example to lubricate bearings or seals of the engine. The Ölleitsystem 104 also has one or more oil filter systems shown here, with an oil filter system 1 in enlarged detail X of 1 is shown. The oil filter system 1 has an oil filter 1F, which is formed in an oil line 1L, shown schematically here, for conducting operating oil 1B in the direction of flow. In the present case, the oil filter system 1 also has an oil differential pressure measuring device 1M, comprising a first pressure sensor S1 arranged in the flow direction before the oil filter 1F and a second pressure sensor S2 arranged in the flow direction after the oil filter 1F. The first pressure sensor S1 is for detecting and indicating a first oil pressure p1 before the oil filter 1F, and the second pressure sensor S2 is for detecting and indicating a second oil pressure p2 after the oil filter 1F.

The first and second oil pressure p1, p2 is only an example of a number of oil pressures that can be recorded with corresponding pressure values from the first and second pressure sensors S1, S2 and possibly other pressure sensors before, after or on the filter 1F. The oil supply system 104 can also have a number of oil filter systems with one or more oil filters, of which only one oil filter system 1 is shown here as a schematic example. In this respect, the particularly preferred embodiment described here is not limited to the embodiment with a single oil filter system 1, but can be implemented at a number of points in the oil supply system 104 by means of a number of oil filter systems 1. In the present case, the first and second oil pressure p1, p2 is applied to an in 2 Control and regulating device 10 shown in more detail--also called "device for controlling and regulating 10"--of internal combustion engine 100 is transmitted. Internal combustion engine 100 has, among other things, a 1 "Engine Control Unit" (ECU) 10 shown.

In the 2 The control and regulating device 10 shown is only shown schematically with regard to its functionality and in this respect does not limit the implementation as a system or structural unit; Rather, this control and regulating device 10 can be realized in part or in its entirety on a vehicle or networked with a vehicle. In addition to the actual engine control unit ECU, the control and regulating device 10 includes a diagrammatically illustrated engine map module 10.1 and an analysis module 10.2; With the exception of a sensor system S, these can but do not have to be part of the engine control unit ECU—in a preferred embodiment, the units explained below, with the exception of a sensor system S, are part of the engine control unit ECU.

The sensor system S is assigned to the map module 10.1 (eg with the pressure sensors S1, S2 mentioned) for determining operating parameters BP of the internal combustion engine and others Sensor data D. The operating parameters BP can include, for example, the engine operating parameters MOTs and oil parameters Öls mentioned here. Part of the sensor system S is, for example, the previously explained oil differential pressure measuring device 1M with the first and second pressure sensors S1, S2; this supplies the already mentioned oil pressures p1, p2.

The sensors of the sensor system S, which are aligned with respect to the operating oil, also include an oil temperature sensor for determining an oil temperature T _oil . Furthermore, the sensors of the sensor system S include engine sensors, for example on the crankshaft of the engine in the area of reference number 101 for determining an engine speed n _MOT and various other performance-related engine data, such as an engine torque M _MOT not shown here, an engine temperature, a coolant throughput or the like ; this can also include load queries and other performance data or vitality data of the engine.

How further from 2 As can be seen, the engine operating parameters MOTs and the oil parameters Öls, the engine speed n _MOT and the operating time h _B of the engine can be determined by means of appropriate sensors as part of the sensor data D; these are only examples here as part of the sensor data D in 2 shown. Such and other sensor data D can be summarized in one or more characteristic diagrams K in the characteristic diagram module 10.1 and, for example, for pre-control of the internal combustion engine or the motor, can be kept in the characteristic diagram module 10.1 as part of the control and regulation device 10; the map module 10.1 is preferably housed in the structural unit of the engine control unit ECU. In particular, the map can be stored there as a standard map in the map module 10.1, in which standard pressures or standard differential pressures for a standard engine and/or a standard operating oil are stored in relation to a number of operating parameters MOTs of the engine and/or oil parameters of the operating oil. The map K is preferably learned at the beginning of the life of the engine and then represents a reference for standardizing all future measured values _Δpi . Oil differential pressures Δp _i can be divided by the standard differential pressures of the map K and/or averaged to Δp and then stored in the trend map Tk at the times hi.

An example of the present preferred embodiment is in 2 a characteristic map K is symbolically shown, in which an engine parameter MOTs—namely here the engine speed n _MOT —is shown on an X axis and an oil parameter oil—namely the oil temperature T _oil in this case—is shown on the Y axis. In particular, a standard characteristics map K of standard differential pressures for a standard engine and/or a standard operating oil can be created in relation to a number of operating parameters B of the engine and/or oil parameters of the operating oil. For such operating parameters B=(T _oil , n _MOT ) that can be represented in the system, a relation variable R that takes into account the first and second oil pressure is also represented here; this in turn can be detected during operation of the specific engine. In the present case, the relational variable R is detected as the oil pressure difference between the second oil pressure and the first oil pressure during operation of the specific engine and is shown here as the oil pressure difference Δp=p2−p1.

The three-dimensional standard map K that is appropriate here, as an example, can also be more complex or comprehensive and is available to the engine control unit ECU; For this purpose, the standard map K is stored in the engine control unit, as explained; however, it can also be available remotely, ie it can be called up by the ECU from a control center, for example.

In 2 it is first shown schematically that a relation variable R taking oil pressures into account is used over a number of oil parameters Öls and a number of engine parameters MOTs. That is, for several or more operating parameters B, a relational variable R is plotted in a normalization map K (standard map), with the present relational variable R being the difference between the second oil pressure and the first oil pressure when a healthy engine is operating with new oil and a new filter as a function is recorded by oil temperature and speed.

A relation variable R or a normalized relation variable value R that takes into account the oil differential pressure Δp _i can in any case be calculated in different ways from the oil pressures.

The present embodiment provides a normalization map K of normal differential pressures Δp_norm i or . In this respect, this indicates normal differential pressures Δp_norm i or at least normal pressures (p1, p2)_norm of a healthy engine with new oil and new filter as a function of oil temperature and speed. It is used to convert the actual measured values p1, p2 or the actually measured oil differential pressure (p2-p1)=Δpi=f (oil temp, engine speed) in an in 2 to normalize the trend field T shown on the right in the sense that it is independent of the oil temperature and the engine speed - this can be achieved most easily by a division in which For example, the oil differential pressure formed from the actual measured values p1, p2 (p2-p1)=Δpi is divided by the difference in normal pressures (p1, p2)_norm. Expressed in general terms, a number of relational variable values (R ₁ , R ₂ , R ₃ , R _i ) taking into account the differential oil pressure Δp _i are converted by means of the standard characteristic map K to a standardized relational variable value R, ie converted into then standardized dimensionless values Ri .

In a modification, there can also be a characteristic map of standard pressures p_norm i that is not shown in detail. This then represents normal pressures p_norm i of a healthy engine with new oil and a new filter as a function of oil temperature and speed. The measured oil pressures can be used for the oil pressure relation, in particular the oil differential pressure, in relation to a number of operating parameters B of the engine and/or oil parameters of the operating oil are recorded in a map K - from this the oil pressure relation, in particular the oil differential pressure, can be determined and recorded in a map K in relation to a number of operating parameters B of the engine and/or oil parameters of the operating oil .

In detail, a trend field T --as shown schematically in 2 indicated on the right-- in 3 illustrated with two examples of a trend. For the purpose of the present embodiment, an oil pressure difference Δp measured across the oil filter 1F is specifically applied to an oil temperature T _oil and an engine speed n _MOT - in this case, the relational variable R is therefore directly determined by the oil pressure difference measured across the oil filter 1F Δp specified; in principle, however, another type of relational variable is also conceivable, for example a quotient. In most cases, it has also proven to be advantageous, as explained, that such a normalization map K --comprising oil pressure-taking relation variables R--is used to form an above-mentioned Δpnorm, ie for example--over oil parameters and engine parameters MOTs to be converted to a relational value Δp (here Δp _norm), which, as the normalized differential oil pressure, takes into account the operating parameters B for which the differential oil pressure was measured, but which is independent of the operating parameter B.

The conversion takes place with a converter algorithm A in a converter module W as part of an analysis module 10.2. The converter module W operates a converter algorithm A, which uses the map data Δp_norm of the map K _NORM with the aid of the operating parameters B of the engine speed n _MOT and the oil temperature T _oil ; in this case to normalize the measured oil pressure difference Δp and convert it to the normalized value R using division. The details of such a converter algorithm A can be formed appropriately and individually for the internal combustion engine 100 . 3 shows in view (A) a first trend field T _a and in view (B) a second trend field T _b , each for determining a trend deviation ΔT between a further relation variable value and a previous trend development in a different way. In principle, a trend development is to be understood as any recognizable and, if necessary, mathematically interpolable or otherwise comprehensible, mathematically analyzing specification of a development of the relational values over the operating time points.

In the present case, a trend development over the operating time points is given by specifying an interpolating compensation curve for the relation variable values over the operating time points, namely as a regression line of the 3 based on the least squares method. In particular, a trend can include the specification of a gradient of the interpolating compensation curve, namely the regression line here, or a trend development can include specification of an interpolating--and possibly extrapolating- compensation curve, namely here the regression line.

It has been shown within the scope of a development already to be mentioned here that a trend development up to a specific point in time during operation can be referred to as a normal trend development. In the present context, a normal trend development is to be understood first of all in general as any trend development to be expected without a change in the condition of the oil in the narrower sense, with which a comparison is made for a further additional operating time point in time that is added to the number of operating time points; namely to determine a relevant trend deviation ΔTg, ΔTe caused by the at least one further relation variable value from the trend development present up to that point, in particular trend development referred to as normal trend development.

Within the scope of a further development specified here, a certain normal trend development can advantageously be assumed under certain conditions; For example, if one assumes the behavior of an engine that does not show any change in the condition of the oil in the narrower sense. In a further explained here first variant of a development - for example, primarily in a diesel or Otto engine - from an overall increasing trend TK1 the 3 be assumed in the behavior of an oil differential pressure or the like oil pressure relation. In a second variant of a further development--for example primarily in the case of a gas engine--one can assume a constant or decreasing trend an oil differential pressure or the like oil pressure relation can be assumed. Both variants are explained below. Further referring to 3 with a first trend field T _a within the scope of a long-term trend development Eg—ie a trend development Eg on a rather longer time scale, in particular in the range from 100 to 500 or 1000 operating hours—or with a second trend field T _b within the scope of a short-term trend development E ₁ -ie a trend development E ₁ on a rather shorter time scale, in particular in the range of perhaps 0.5 to 1 or 10 operating hours, in particular in the hour range -- for a further number of operating time points hi additional service life time hi a further relation variable value R _i+1 in relation to a relevant trend deviation ΔT from the trend development E caused by at least one further relation variable value R _i+1 analyzed as a decreasing trend deviation.

Within the scope of a particularly preferred embodiment, the trend T in the present case includes, in particular, an indication of a slope in the trend characteristic map Ta and trend characteristic map Tb; Specifically, the development of a slope of a trend curve TK1, TK2, TK3 can be recorded.

In 3 it is shown that the relation variable R, which is independent of the operating parameters, is based on the number of oil pressure differences Δp with relation variable values R ₁ , R ₂ , R ₃ , which normalizes with the normalization map K for various operating parameters B and results in an operating time -Time hi, i=1, 2, 3 were determined; the values of the operating time times hi, i=1, 2, 3 are referred to below as Z ₁ , Z ₂ , and Z ₃ . The relative variable value R, which is independent of the operating parameters in this respect, is used as a normalized differential pressure Δp_norm i --as in relation to 3 explained in more detail-- transferred to a trend field T. In a real case, the trend field T is available as a data record in which the operating parameters are independent of the relation variable R--here the values of the normalized (possibly also integrated) mean values Δp of the oil pressure differences Δp-- is related to a curve over the operating period h _B or a corresponding number of operating times hi, i=1, 2, 3, whose values are referred to below as Z ₁ , Z ₂ , and Z ₃ are indicated.

The control and regulating device 10 according to the 2 thus includes, in addition to the sensor system S for detecting engine parameters MOTs and oil parameters Öls, one or more characteristic diagrams K for normalizing the oil pressure differences Δp or other relational variables R for an operating time point hi, i=1, 2, 3 in the operating time h _B and for different operating parameters B of the internal combustion engine.

By means of a converter module W mentioned above and a corresponding conversion algorithm A, it is possible to use this to store a profile of relational variable values Ri that are independent of operating parameters over a time axis; in the present case, these are the mean values normalized using Δp_norm Δp of the oil pressure differences Δp. An averaging makes sense in this respect; but if the raw value Δp is offset against R, an initially normalized value is to be assumed here, which, as explained above, can initially be regarded as independent of the operating parameters of the corresponding operating point. Δp can then also be a normalized mean value.

3 shows exemplary trend fields, namely in view (A) a first example of such a trend field T _a and in view (B) a second example of such a trend field T _b . jr 3 Example (A) is plotted over the operating time h _B (e.g. in operating hours) of an internal combustion engine 100, a relation variable R independent of the operating parameter, ie for a number of operating time points hi, i=1, 2, 3 is a number _{Relational variable values} R ₁ , _{R 2} , _{R 3} Δp given as a trend development E. A trend development E is designated here for the trend field T _a as a long-term trend development Eg. In the present case, the long-term trend development Eg is characterized by an upper and lower limit development G _o and G _u . In this way, for each existing and then added relational value R ₁ , R ₂ , R ₃ - i.e. finally the relational value R3 -- a so-called first, i.e. previous, trend curve TK1 results, which in this case is at the upper limit development G _o lies.For the in view (a) of the 3 in the first trend field T _a then subsequently, further operating duration time at hi, a further relational variable value Ri is entered here and as the result of a cumulative consideration of R ₁ , R ₂ , R ₃ . . . R _i etc. for time values Z ₁ , Z ₂ , Z ₃ . . . Z _i etc., a second, ie further, trend curve TK2 can be specified. This leads to a trend deviation .DELTA.T, which is essentially measurable with a long-term trend deviation .DELTA.Tg and which clearly stands out from the previous trend development between the limit developments G _o , G _u ; ie which falls outside of the confidence interval T _B limited by it. Strictly speaking, however, the trend curve TK1 in view (A) is no longer linear in the long-term trend with added R1, R2, R3; another possibility for determining a long-term trend recognition therefore includes, for example, a linear regression, which can also be used for an extrapolation.

This type or other expedient type of determination that a further trend curve TK2 recognizably falls outside the confidence range TB of previous trend curves _TK1 is referred to here as an evaluation of a long-term trend development Eg.

In 3 Example (B) shows what is known as a short-term trend development E ₁ . Relational variable values R ₁ , R ₂ , R ₃ and R _i are again given for operating times hi, i=1, 2, 3, with each relational variable value R _i , i=1, 2, 3 being an averaged integrated operating size value Δp is assigned to the oil pressure difference Δp = p2 - p1.

In this second trend field T _b it can be seen that the other relational value Ri deviates significantly from the previous trend curve TK1 of trend field T _b and the local trend deviation ΔT ₁ can -- as with the distance calculation for the long-term trend development Eg in 3(A) -- be evaluated by means of a distance calculation, in particular a difference formation, in the coordinate system described above. This type of distance calculation for a local trend deviation ΔT ₁ is referred to here as an evaluation of a short-term trend development E ₁ . In particular, a short-term trend, like a long-term trend, can be calculated using a difference quotient in the sense of a slope of the trend curve; ie in terms of trend T = ΔR/Δt = (Ri-R3)/(hj-h3); a differential quotient is also possible; in these cases, the measured values do not need to be equidistant.

In both examples (A) and (B) the 3 a significant trend deviation ΔT can be determined in the trend field T _a or T _b . In example (a) in trend field T _a , trend deviation ΔT can be recognized as global trend deviation ΔT _g in that a further trend curve TK2 clearly falls outside the confidence range T _B of previous trend curves TK1. In example (b) in the trend field Tb, the trend deviation ΔT can be recognized as a local trend deviation ΔT ₁ in that a distance between a further relation variable value Ri and the previous trend curve _TK1 is significantly greater than before, ie the relation variable value Ri deviates extremely clearly from the previous trend curve TK1. One could also notice that another trend curve TK3 is no longer linear.

As a result, the preferred embodiment provides that on the basis of such a representation of relational values R ₁ , R ₂ , R ₃ independently of the operating parameter B of an engine and an analysis of trend developments Eg or E ₁ based on this (here using the trend fields T _a , T _b and a corresponding developing trend curve TK) a trend deviation ΔT is detected, for example as in 3A respectively. 3B shown global trend deviation ΔT _g or local trend deviation ΔT ₁ . A trend deviation ΔT can then be used as an indicator of an oil condition and a change in the same. The oil condition is thus determined on a very reliable model, which takes into account all operating parameters of the internal combustion engine, of an oil pressure difference Δp or of oil pressure differences Δp _i across the oil filter 1F. It has been shown that if a trend deviation ΔT (eg the previously explained global or local trend deviation ΔT _g or ΔT ₁ ) is significant, a status signal can be output that can indicate a significantly impaired oil condition.

Such a procedure is shown schematically in 4 shown with a flow chart. In a first step V1, test conditions and resets can be implemented that are intended to make the measurements and evaluations reliable and, in particular, to avoid falsifications; Examples of such test conditions and resets are given in relation to 8C explained. For example, the history of an oil filter 1F can be considered. A zero point adjustment of the two pressure sensors can also be carried out in the "Engine STOPPED" operating state in order to rule out offset errors in the sensors.

In a step V2, operating parameters of the engine and the oil can be measured via an oil filter 1F; in this case, for example, the engine speed n _MOT , called the oil temperature T _oil - there is also an oil pressure difference Δp _i determined on the basis of the oil pressures p1, p2 at a specific operating time point and the operating time h _B of the internal combustion engine, which is also shown in 2 are shown.

As a result, in a step V3, a map K of the internal combustion engine can contain the operating parameters BP of the aforementioned type and the oil pressure difference Δp _i for a number of operating time points hi, i=1, 2, 3, for example as a possible relational variable Ri for a Plot the number of operating time points hi, i=1, 2, 3 and the operating time h _B together.

Such a characteristic field K can be converted in a fourth step V4 by means of a corresponding converter algorithm A to display a trend development T. Step V4 can, for example, be carried out using an in 2 Analysis module 10.1 and converter module W(A) shown schematically can be implemented. For this purpose, a converter algorithm A is based on a number of relational variable values R _i relating to the oil pressure difference Δp _i to the operating Duration times hi, i=1, 2, 3 and the operating time h _B . Here, this includes in particular a trend curve TK, which in step V5 as a function T ( Δp _i , h _B ) is indicated; ie which depends on the number of oil pressure differences Δp _i is (Δp _i temporally filtered, averaged, summed or integrated over all operating states at an operating time point in time hi) and is dependent on an operating time h _B of the internal combustion engine. The trend deviation ΔT explained above can be analyzed with regard to a significance, for example, in an analysis module 10.2 in step V6, as is the case on the basis of FIG 3 was explained. As an example, a threshold value check of the trend deviation ΔT or of the trend T is possible, in which it is determined whether a trend deviation (in comparison to an existing trend within the scope of a trend change) exceeds a predetermined threshold value SW; this can primarily concern a deviation in an absolute value, but also a deviation in a slope value. The trend deviation arises in this respect primarily as a result of an additional relational variable value, so that a further trend development deviates from a previous trend development E. The trend deviation ΔT can be determined on the basis of a long-term or short-term trend deviation ΔT _g or ΔT ₁ as shown in FIG 3 was explained. In a step V7, the trend deviation ΔT can be examined with regard to the sign. For this purpose, the query "ΔT <0" as part of a deviation check in step V8 specifies whether a trend deviation ΔT is below zero. If this is the case, an oil dilution can be concluded. If the trend deviation .DELTA.T is negative--ie if .DELTA.T is below zero--oil dilution can be inferred in a step V9. In order to improve the robustness of the method, in addition to the global (insofar as long-term) trend, above all the local (insofar as short-term) trend can be used for detecting the oil dilution. For example, if T is interpreted as a slope value in the manner mentioned above, a trend deviation ΔT is less than zero if the corresponding trend curve bends downwards in the sense of a changed trend development. In a first embodiment, the absolute value of the amplitude mentioned can also be additionally or alternatively monitored as an absolute value of a gradient. For this purpose, for example, a specific threshold smaller than S1 can be specified and monitored using the query T<S1.

In a modification, it is also possible to monitor the trends directly for limit values. For example, a query S1<T<S2 can be used to check whether there is oil dilution if the trend T falls outside the acceptable range [S1, S2]. A query S1>T can also be used to check whether the filter has been replaced.

The embodiment has recognized that the oil dilution can be caused by diesel fuel or cooling water entering the oil circuit and which represents the relevant process flow. This results in the loss of lubricity and a corresponding reduction in viscosity.

This is clearly recognizable above all in comparison to a normal trend development if, under certain circumstances and with a specific engine (e.g. diesel or Otto engine), one assumes a fundamentally strictly monotonous course of a trend development E of a differential pressure Δp _i could accept via a filter; ie the requirement that the differential pressure Δp _i increases strictly monotonically over the operating time points hi, i=1, 2, 3 is based on the assumption that when soot develops in a diesel or Otto engine, a filter normally becomes increasingly clogged and increases its differential pressure Δp _i . The concept of the invention provides for the number of relational variable values R ₁ , R ₂ , R ₃ , R _i --as explained above-- to be assigned to a trend development E over the operating time points in time hi; From this, a kind of normal trend development for the specific engine or engine type is regularly recognizable, such as a diesel or Otto engine here.

in Betracht kommen. Ein entsprechend abgewandelter Ablauf für einen Gasmotor könnte umfassen:

• - im Schritt V2
  • - Bilden von Δp_i über den Öldruck
  • - Glätten (z.B. über einen Zeitfilter) von Δp_i Öldruck zu Δp _i
• - im Schritt V5
  • - Normieren des Öl-Differenzdrucks und Darstellen als Relationsgröße R = Δp _i/Δp_norm
  • - Bilden einer Trendaussage auf Basis eines Differenzen- oder Differential-Quotienten Ti = (Ri - Ri-1)/ (hi-hi-1)
• - im Schritt V6 bis V8

S1<T<S2 - wenn ja, Ölverdünnung
T<S1 - wenn ja,, FiltertauschOn the other hand, the monotonous increase in differential pressure does not normally occur in gas engines, since they do not produce soot. This means that the above query V6, which applies primarily to a diesel or Otto engine, does not always indicate oil dilution. This would also be recognizable in a gas engine if the number of relational variable values R ₁ , R ₂ , R ₃ , R _i --as explained above-- is assigned to a trend development E over the operating time points in time hi; From this, a kind of normal trend development for the specific engine or engine type is regularly recognizable, such as a gas engine here. Then in the flow chart of the method of 4 in modification of the query V6 of 4 Queries on absolute gradient limits or changes in gradient are more effective. Here, for example, the query could be $$\begin{array}{l}\text{slope T < threshold1}=\ddot{\text{O}}\text{lverd}\ddot{\text{and}}\text{well}\\ \text{slope T < threshold2}=\text{filter replacement}\end{array}$$

be considered. A modified process for a gas engine could include:

• - in step V2
  • - Forming of Δp_i over the oil pressure
  • - Smoothing (e.g. using a time filter) of Δp_i oil pressure Δp _i
• - in step V5
  • - Normalizing the oil differential pressure and displaying it as a relational variable R = Δp _i /Δp_norm
  • - Forming a trend statement based on a difference or differential quotient Ti = (Ri - Ri-1)/ (hi-hi-1)
• - in step V6 to V8

S1<T<S2 - if so, oil dilution
T<S1 - if so, filter replacement

A trend development E of the relational variable R with a filter model verifies this processing of the first and second oil pressure by means of a relational variable that takes this into account in relation to an operating time h _B of the internal combustion engine (given in operating hours, for example). 5 shows a schematic representation for a first preferred embodiment relating to the conversion of measured oil pressures to a relational variable value that is independent of an operating parameter, using a characteristic map and a converter algorithm. This is a comparatively sophisticated approach. Relational variable values and a trend development are shown in an exemplary trend characteristics map T _a over operating time points for a method for detecting an oil condition of an operating oil for an engine of the internal combustion engine.

5 shows relational variable values R ₁ , R ₂ , R ₃ resulting from the test or pre-operation of an internal combustion engine at operating time points hi, i=1, 2, 3 whose values here are Z ₁ , Z ₂ and Z ₃ are specified. These are assigned, for example, learned differential pressures as relation variable values R ₁ , R ₂ , R ₃ in the map K of operating parameters B, namely an engine parameter and oil parameter, namely engine speed n _MOT and oil temperature T _oil . A standard characteristic diagram K of standard differential pressures can thus be created for a standard engine and/or a standard operating oil in relation to a number of operating parameters B of the engine and/or oil parameters of the operating oil. The standard map is preferably learned in the first hours of operation when the filter and the oil are still new. This saves the individual behavior of this machine when it was new. In a modification or addition to this procedure, the standard characteristic map can also be pre-initialized with empirical values or finalized.

In this respect, Ri stands for a matrix of relation variables R _i (n _MOT , T _oil ). In the present case, the relational variable values Ri for _i =1, 2, 3 for a certain operating parameter B.

The converter module W now executes a converter algorithm A, which uses all operating parameters B, ie in this case the oil pressure difference Δp as it results from the actual operation of an internal combustion engine to specify relational values R ₁ , R ₂ , R ₃ at operating time points hi, i=1, 2, 3 normalized in actual operation to one or the respective operating parameters B, ie averaged or divided or integrated over the operating parameters B or the oil pressure difference Δp otherwise normalized in relation to the operating parameters B. A in this "Normalization" to be understood in a general sense can therefore include averaging or integration and/or quotient formation, each for one of the operating time points hi, i=1, 2, 3, whose value is given here Z ₁ , Z ₂ and Z ₃ , (e.g. in each case for Z ₁ , Z ₂ , Z ₃ etc.).

If necessary, the integration takes into account weightings, frequencies and priorities of the mentioned oil and engine parameters oil, MOTs and forms an integrated mean value that is possibly weighted in this respect Δp for times hi in the operating time h _B of the internal combustion engine from what in 2 is shown on the right.

Forming a quotient can normalize a specific oil pressure difference Δp, for example, to a respective operating parameter B or to the operating parameter B of a standard; this is in relation to the embodiment in FIG 7 described in more detail.

In the present case, the converter algorithm A is executed by means of a trigger at the operating times hi, i=1, 2, 3, whose value is given here as Z ₁ , Z ₂ and Z ₃ . i.e. the matrix R _i (n _MOT , T _oil ), which includes several oil pressure differences Δp _i for one of the time values Z ₁ , Z ₂ or Z ₃ , as they are recorded in real operation of an internal combustion engine, is used for an operating duration time hi condenses to an integrated, averaged, summed, or otherwise summarized relational value Δp _i independent of the operating parameter B for this one operating time point in time hi.

The map K is therefore learned at the beginning of the engine's life and then represents a reference for normalizing all future measured values Δpi Δp and stored in the trend map Tk at the times hi. To put it another way, the 3D field of relational variable values R ₁ , R ₂ , R ₃ shown on the left at early service life times hi, i=1, 2, 3 is specified here as Z ₁ , Z ₂ and Z ₃ are utilized to later set operating values to a value Δp _i to compress at an operating time point h _i , i=1, 2, 3. This is in the middle of the 5 shown.

As an output of the converter and analysis module W in the analysis module 10.2 as a result of the converter algorithm A used, sequences of operating parameters assigned to the matrix Ri can have independent relation variable values Δp _i be plotted like this in 5 is shown on the right. In this way, a trend characteristics map is created over a number of operating time points in time hi with values Z ₁ , Z ₂ and Z ₃ as Δp ₁ , Δp ₂ and Δp ₃ etc. to Δp _i . On the basis of these relational values, a single trend curve or a group of trend curves TK can be specified, which are distributed more or less over a confidence area _TB of a trend development E. In the present case, the confidence range T _B is surrounded by an upper limit development G _o and a lower limit development G _u . The confidence range T _B is advantageously also written in a logic. This can be implemented with a suitable, intelligent and possibly learning logic of an analysis module 10.2. In this case, for example, it can be taken into account that relational variable values that were first adapted are less relevant for a long-term trend due to run-in effects on the internal combustion engine. Such and other boundary conditions can be taken into account within the framework of an intelligent evaluation; Examples are in 8th specified.

It is noticeable that in the map of the K 5 for a further relational variable value Ri added to the number of relational variable values R ₁ , R ₂ , R ₃ for operating time points in time Z ₁ , Z ₂ , Z ₃ for an operating time point in time value Z _i up to then or currently strictly monotonous trend development is disturbed - Δp represents the oil differential pressure intended for this purpose.

As in the previously explained procedure as part of a converter module W and analysis module 10.2, a converter algorithm A triggers the operating time points in time Z ₁ , Z ₂ , Z ₃ each with a matrix of relational values Ri, for example at the operating time point in time value Z _i for a matrix of oil pressure differences Δp _i as a function of engine and oil parameters n _MOT , T _oil and forms an operating parameter B-independent relation value R _i , which is used here as Δp _i is drawn as a bright dot in the trend field.

This further operating parameter independent relation size value Δp _i (shown in light) is clearly deviating from the relative values Δp1, Δp2, Δp3, which are independent of the operating parameters and are shown in dark, which were used for the previous trend curve TK1 - a (local) trend deviation ΔT ₁ is therefore clearly recognizable and is referred to here as a so-called short-term trend development E ₁ analyzed (as shown by 3 (B) explained). That is, the trend deviation ΔT ₁ of the further relation quantity value Δp _i itself of the "normal" short-term trend development E ₁ present at the operating time Z _i according to the previous trend curve TK1 can be analyzed, for example, within the framework of a differential calculation or other distance measurement in the trend field T _b . For this purpose, the measures of step V6 of the procedure in 4 be made. The further steps V7, V8 and V9 of the process sequence in 4 can also be verified here. It turns out that the other relational value Δp _i with the trend deviation ΔT ₁ would reduce an increase in the previous trend development E ₁ ; that is, a further trend curve TK2 T _b would be obtained when this further operating parameter-independent relation variable value is taken into account Δp _i decrease - the further trend curve TK2 is in 5 drawn in dashed. This result, in which a strictly monotonous trend development is disturbed, indicates a reduced viscosity of the operating oil, which in turn indicates oil dilution by fuel. The following explains how such an evaluation can be used to plan orders for individual parts for an internal combustion engine, in particular the oil filter, at an early stage.

6 shows exactly the trend map T _a der 5 with the trend development E in an enlarged representation, ie with the confidence interval _TB in a hatched representation. In addition, the first tolerable relational value for a lower differential pressure, labeled “Limit Yellow”, is indicated Δp and a second, even higher, maximum tolerable relational value, labeled “Limit Red”, for a higher differential pressure Δp shown; both as a horizontal dashed line.

Of course, the trend curve on which "Case 2" is based - namely the upper limit development G _o -- means that the "Limit Yellow" is reached earlier, so that the ordering time ET2 for an individual part in "Case 2" is clearly before the order time ETI for an individual part is in "Case 1", whereby "Case 1" is based on the lower limit development G _u and in both cases rather shorter order times of an individual part order duration are denoted by t1.

However, an individual part ordering time t1 (earlier expected time) in "Case 1" is longer until the "Yellow Limit" is reached than the individual part ordering time t1 (earlier expected time) in "Case 2" until the "Yellow Limit" is reached. In both cases, however, an operating fault also remains tion possible; This is the result of the difference between "Limit Red" and "Limit Yellow", since in both cases a longer individual part ordering time t2 (later expected time) up to "Limit Red" is longer than a shorter individual part ordering time t1 (earlier expected time) up to to the “Limit Yellow”. This procedure has proven itself, for example, when determining a filter replacement, in order to coordinate the duration of an individual part order with regard to the required operating reaction. For example, a waiting time can be used for the "yellow limit" until the end of a shift in which a vehicle with an internal combustion engine is used. If the "Limit Rot" is reached, however, an operational reaction without delay is required. An expected time for reaching the "yellow limit" or "red limit" alarm level can be calculated using the previously explained trend curve TK, which is usually in a group of trend curves TK in the confidence interval _TB ; such a trend curve TK is an example in 6 drawn.

7 now also shows the possibility of such a, as in 5 illustrated learned or otherwise compiled filter differential pressure map K to use to detect an oil condition. Compared to the approach of the embodiment of FIG 5 , indicates 7 an easier-to-implement approach; for example, it is easier to program or there is less computing effort.

7 shows first symbolically with reference to the detail X of 1 an oil filter system 1 in connection with a control and regulation scheme 11 for a control and regulation device 10. First of all, the oil filter system 1 is analogous to the representation in detail X of 1 shown with an oil filter 1F for operating oil 1B in an oil line 1L for supplying oil to a motor 101 of an internal combustion engine 100. A differential oil pressure Δp is made available by means of a first and a second pressure sensor S1, S2 for determining a first and a second oil pressure p1, p2. In the present case, the second pressure p2 is subtracted from the first pressure p1 in a comparator 12. In the present case, the comparator 12 is designed as a difference generator. In principle, however, such a comparator could also produce some other relationship between the second and first pressures p1, p2, for example by subtracting the first pressure from the second pressure, which would also correspond to forming a difference. In principle, however, a comparator 12 can also be formed differently, for example by forming some other relationship between the second and the first pressure; for example by forming the quotient of the pressures p1, p2 - this means that a relative pressure value can also be made available as a measure of a pressure drop across the oil filter 1F.

Within the scope of the present embodiment, forming a difference in the comparator 12 has proven to be advantageous, so that within the scope of the control scheme 11, an oil differential pressure is made available as the actual value _{Δp_IST} .

The control and regulation device 10 is designed to execute the control and regulation scheme 11 using a characteristic map module 10.1 and an analysis module 10.2. The control and regulation scheme 11 is specifically designed here with a converter algorithm A, which normalizes the determined oil pressure differences Δp with a standard pressure Δp_ _NORM to form relational variable values of a trend characteristic map T _a as part of a quotient formation. This is explained in more detail below.

The oil pressure relation, present in the form of a differential oil pressure Δp, specifically an actual value Δp_ _IST of the same, is related to a standard differential oil pressure Δp_ _NORM . In the present embodiment, the standard oil differential pressure Δp_ _NORM is the result of a standard; that is, a theoretical design for a standard engine with certain operating parameters and associated differential oil pressures across filter 1F. The standard differential oil pressure _{Δp_NORM} is stored as the differential oil pressure for such a standard in a normalized differential oil pressure map K for the filter 1F.

The so-called oil differential pressure map K for normalization is in detail X der 7 shown in more detail and stored in a first part of the map module 10.1.

In terms of its coordinates, the normalized oil differential pressure map K, referred to as such below, is similar to the map K of 5 educated; In contrast to this, however, it does not show oil differential pressure values as current measured values of the oil differential pressure measuring device 1M, but rather as a standard, i.e. oil differential pressures to be assumed for a standard engine for operating parameters B of engine 101.

In the present case, in the normalized oil differential pressure map K, these are again the oil temperature T _oil and the engine speed n _MOT for which standard oil differential pressures are recorded as standard pressures _{Δp_NORM} . This essentially corresponds to a matrix in which a standard oil differential pressure Δp _NORM in relation to an oil temperature T _oil and an engine speed n _MOT is recorded as a standard. In this respect, the oil differential pressure map K for the filter 1F is given the designation K _NORM here. The normalized map K _NORM is stored in the map module 10.1 and connected in terms of regulation or control to the output of the comparator 12, which represents the actually measured oil differential pressure Δp, namely its actual value Δp_ _IST supplies. Furthermore, the map module 10.1 has inputs not only for parameters of the engine speed n _MOT and the oil temperature T _oil , but other operating parameters B can also be included. As an example of further operating parameters B, performance parameters (for example torque or a torque request M) or a coolant temperature T _KM are listed here for the normalization oil differential pressure map K _NORM .

The normalization differential oil pressure map K _NORM is in this respect a multi-dimensional map with five coordinates in the present case, in which the normal oil differential pressure is set in relation to a standard engine, ie is set in relation to a number of operating parameters B; Above all, the speed n _MOT and operating oil temperature T _oil as well as torque or a torque requirement M or a coolant temperature T _KM are shown in more detail here.

The converter algorithm A provides that the measured differential pressure Δp (specifically its actual value Δp _IST ) is normalized as part of a quotient formation in relation to the normalization oil differential pressure map K _NORM - the corresponding converter algorithm provides a quotient generator 13 for this purpose, which normalizes the differential oil pressure Δp--as measured-- in relation to the standard differential oil pressure Δp _NORM in an acute operating situation of the engine (determined by the aforementioned operating parameters B: n _MOT TKM T _oil load point M).

This can be done, for example, in such a way that with a specifically known operating parameter B such as engine speed n _MOT and operating oil temperature T _oil , the standard oil differential pressure Δp _NORM is taken from the standard map K _NORM as a known standard value and the actually measured oil differential pressure Δp in the quotient generator 13 Division is supplied to form a normalized relational value R in the sense of $$\text{R}=\frac{\Delta \text{pIST}}{\Delta \text{pNORM}}\left({\text{n}}_{\text{ENG}\text{,}}{\text{T}}_{\ddot{\text{O}}\text{l}}\right).$$

According to the present embodiment, the relational variable value R to be used in the open-loop and closed-loop control scheme 11 is a normalized relational variable value R that is recorded in a normalized trend characteristics map for a plurality of operating time points hi at a specific operating time.

In the present example of control scheme 11, this is shown in detail Y as part of characteristic map module 10.1 in a trend characteristic map T _a —that is, to record the normalized oil differential pressure—the oil differential pressure Δp is normalized with a standard oil differential pressure Δp _NORM -- a number of normalized relational variable values Ri for operating duration times hi are repeatedly applied as part of the control scheme implemented with the difference former 12 and the quotient former 13 .

1. 1. Öl-Alterung und
2. 2. Öl-Verdünnung.
3. 3. Filtertausch
4. 4. Öl-Nachfüllvorgang

This separation characteristics map is made available as a normalized separation characteristics map T _a to an aforementioned analysis module 10.2 in order to carry out a trend analysis, as is based on FIG 2 , 5 and 6 has already been explained. In this respect, a value R _j of a normalized relation variable value is also shown with an open symbol in the normalized differential pressure characteristic map T _a , which reveals a deviation from the trend. That is to say, the further relational variable value R _j causes a trend deviation ΔT from the trend development E to below the trend development E. This trend deviation ΔT can be determined using a specific mathematical procedure in the analysis module 10.2. As explained above, the concept of the invention has also recognized that oil quality is of decisive importance for the service life of an engine, with the analysis module 10.2 recognizing four superimposed effects in particular, namely recognizing and distinguishing them as a result of the Speed of your individual trend.

1. 1. Oil aging and
2. 2. Oil dilution.
3. 3. Filter replacement
4. 4. Oil refill process

The first two effects lead to a reduction in viscosity; the difference lies primarily in the strength of the trend. While a change in viscosity from normal engine operation can be observed for hundreds of hours, the change in viscosity from oil dilution occurs within a few hours. This is used for recognizability/distinction due to the speed of their individual trend.

The effect of the filter is also superimposed - with increasing loading of the filter, the differential pressure across the filter increases, which corresponds to a slow trend.

When a filter is replaced, an oil differential pressure change occurs suddenly as a pressure drop. A sudden increase in the oil differential pressure results from topping up with oil and also occurs suddenly.

8A shows an example of a concrete course of the normalized oil difference seen in this way print Δp with the aforementioned normalized relational values Ri of a trend development E over the operating time h _B of an internal combustion engine with a motor 101 and the oil filter system 1. The representation of the normalized oil differential pressures Δp is to be understood as the trend development E on a scale of operating times in the range of several tens of thousands of hours, ie for example in the range of an operating time h _B of around 20,000 hours.

is shown in 8A a selection of trend deviations ΔT _i at specific operating time times hi, which are denoted here by R _j (i=0,1,2,3) and can be assigned to different events B _i (i=0,1,2,3). . A running-in period of the engine with the operating time h _B =0 (e.g. specified in operating hours) is not taken into account; the value R ₀ of an operating time h _B has, so to speak, an offset O at event B ₀ . A trend development E will be recognizable in the form of a normal trend development over the service life h _B , especially in the case of a diesel engine, it will be monotonously rising, since the oil differential pressure Δp increases as a result of an increasingly clogged filter 1F. A trend development that decreases below an increasing normal trend development is thus to be analyzed as the relevant trend deviation ΔT.

The events B _i (i=1, 2, 3, 4) shown here are various examples with corresponding deviating normalized relational values R _j 1, R _j 2, R _j 3, R _j ''' from the trend development accordingly This caused trend deviations ΔT1, ΔT2 and ΔT3, or ΔT3'.

During event B4 oil aging, the viscosity should essentially decrease with time as the long hydrocarbon chains are broken down by mechanical shear forces. Oil aging causes a decreasing trend signature of oil aging in the trend, which is superimposed on the increasing normal trend development - this can be seen on a long scale of an operating time point h4 in a sub-linear deviation from the linearly increasing trend E. In the course of oil dilution, the viscosity should also decrease, but due to different processes on a different time scale.

With an oil dilution (ÖV1, ÖV2) of event B3, there is also a differential pressure loss as a downward trend. In other words: in the context of the filter model, the trend towards an increasing relation variable taking account of the first and second oil pressure weakens as a result of oil dilution. A trend deviation between the further relation variable value from the trend development can then be evaluated in different ways; be analyzed advantageously in the context of the above short-term or long-term trend development. Event B1 at operating time h1 indicates a filter replacement and event B2 at operating time h2 indicates an oil topping-up process.

The filter replacement at event B1 at operating time h1 has a suddenly decreasing trend deviation due to the suddenly decreasing oil differential pressure Δp result; thus advantageously recognizable on a very short time scale (practically instantaneous) compared to an already shorter time scale of oil dilution.

A change in the oil differential pressure in the form of a sudden increase results from the topping up of oil and also occurs suddenly in event B2.

It is therefore possible to analyze further relational value R _i+1 in relation to a decreasing trend deviation ΔT from the trend development E caused by at least one further relational value R _i+1 as the relevant trend deviation ΔT, with the time extension and/or amplitude , in particular ramp, of the decreasing trend deviation ΔT from the trend development E is analyzed.

Event B3 at operating time point h3 to operating time point h4 includes two variants of an oil dilution process ÖV1, ÖV2.

The events B1, B2 are recognizable events with the filter replacement (B1) and the oil refilling process (B2).

The rapid process of oil dilution ÖV1 of event B3 is the relevant process to be alarmed in the present case, which is recognized within the scope of the preferred embodiment within the scope of the concept for the invention of a trend analysis by means of the oil differential pressure measuring device 1M and the control scheme 11 using the control - and control device 10. The individual events are explained below.

8B shows in view (A) a previously explained model of a long-term trend development Eg (as based on 3 View (A) explained) and a variant of an analysis. A global trend deviation ΔT _g can be coordinated with the further relational value Ri as trend development Eg. The previous trend curve TK1 can also be described as a normal trend development and the further trend curve TK2 as a deviated trend development in comparison to the normal trend development.

The trend curve TK1 of the normal trend development is based on the previously mentioned values Δp ₁ , Δp ₂ and Δp ₃ .

In addition, an operating parameter is an independent relational value Δp _i plotted for the service life time Z _i . The trend curve TK2 of the deviated trend development is created taking into account the further relation value Ri.

1. 1. Zu geringer Öldruck: Defekt im Motor / fehlendes Öl => Notabstellung
2. 2. Zu hoher normierter Differenzdruck => Filtertausch erforderlich => Wartungslampe
3. 3. Ereignis B4: Langsam steigernder Differenzdruck => Wartungsprognose für Filtertausch
4. 4. Schneller Anstieg des Differenzdruckes => Vermutlich innere abrasive Abnutzung (Späne) Motordefekt => Warnung
5. 5. Ereignis B3: Schnelle (innerhalb weniger Stunden, nicht plötzliche) Absenkung ÖV1 des normierten Δp nach unten => Öl-Verdünnung => Alarm gemäß dem Konzept der Erfindung. Es kann beispielsweise festzustellen sein, ob Dieselkraftstoff in den Ölkreislauf gelangt. Dies führt nämlich zu einem maßgeblichen Verlust der Schmierfähigkeit, sodass verschiedene Defekte, wie zum Beispiel Lager- oder O-Ring-Defekte in der Kraftstoffpumpe durch diesen Verlust der Schmierfähigkeit hervorgerufen werden können.
6. 6. Ereignis B1: Plötzliche Absenkung des normierten Δp nach unten => Ursache: Filtertausch => (auch für Big Data Analyse - Alarmunterdrückung vom Öl-Verdünnungsalarm)
7. 7. Der Wert des Δp nach Filtertausch ist ein Maß für die Ölqualität => Wartungshinweis Filtertausch ohne Ölwechsel (nicht Gegenstand der Erfindung)
8. 8. Ereignis B2: Plötzlicher Anstieg des normierten Δp nach oben => Öl wurde nachgefüllt. (auch für Big Data Analyse bzw. in Abgrenzung zu 4.)
9. 9. Ereignis B0: Ausblenden der ersten 100 Motorbetriebsstunden zur Verhinderung einer Fehlanzeige der Trendentwicklung.

A method of oil condition detection can particularly preferably have the following test steps:

1. 1. Oil pressure too low: defect in the engine / lack of oil => emergency shutdown
2. 2. Normalized differential pressure too high => filter replacement required => maintenance lamp
3. 3. Event B4: slowly increasing differential pressure => maintenance prognosis for filter exchange
4. 4. Rapid rise in differential pressure => probably internal abrasive wear (chips) Motor defect => warning
5. 5. Event B3: Rapid (within a few hours, not sudden) lowering ÖV1 of the normalized Δp => oil dilution => alarm according to the concept of the invention. For example, it can be determined whether diesel fuel gets into the oil circuit. This leads to a significant loss of lubricity, so that various defects, such as bearing or O-ring defects in the fuel pump, can be caused by this loss of lubricity.
6. 6. Event B1: Sudden lowering of the normalized Δp => cause: filter replacement => (also for big data analysis - alarm suppression of the oil dilution alarm)
7. 7. The value of the Δp after filter replacement is a measure of the oil quality => maintenance instruction filter replacement without oil change (not subject of the invention)
8. 8. Event B2: Sudden increase in normalized Δp => oil was refilled. (also for big data analysis or in contrast to 4.)
9. 9. Event B0: Hide the first 100 hours of engine operation to prevent the trend development from being displayed incorrectly.

8B shows in view (A) a preferred consideration of a first boundary condition for both trend curves TK1 and TK2; namely in such a way that a running-in period of the engine is not taken into account in the operating time h _B (given in operating hours, for example); so to speak, the value Z of an operating time h _B has an offset O.

The running-in period of the engine ultimately causes non-evaluable data due to the strong fluctuation amplitudes in the viscosity of the operating oil and the offset O taking this into account is in the 8A shown hatched.

8B shows in view (B) based on the case of a short-term trend development E ₁ (as based on 3 View (B) explains) a variant of the trend development T _b for determining a local trend deviation ΔT ₁ . In the event that other relational values Δp _i drop significantly and relatively quickly (ÖV1) below the previous trend development T _b (dark points), this can be analyzed as a short-term trend development E ₁ . A local trend deviation ΔT _e of the further relation variable value is added to this Δp analyzed from the normal trend development (dark points) at the time of operation.

8B shows in view (C) a further boundary condition such that a filter exchange takes place at time Z on a scale of the operating time h _B ; this event was followed by a re-statement of trend development. That is, the trend memory is first cleared at time Z, which is in 8C is symbolically represented by "X". The background is that when a filter is replaced, the change over time Δp/Δt of the operating parameter, which is symbolically represented by a downward arrow, is independent of the relation variable value Δp --namely concerning the in 1 shown oil pressure difference between the second oil pressure and the first oil pressure, Δp = p2 - p1 across the filter-- is strongly negative; that is, a value Δp drops abruptly at a time Z, resulting in 8C is symbolically represented by "X".

In this case, the trend analysis would then have to start all over again and all " Δp "-values are reset to "0". After that, increasing differential pressure values relating to the oil pressure difference between the second oil pressure and the first oil pressure, Δp=p2−p1, would then be detected via the filter in the characteristic map. These are then converted with the converter and analysis module W described or with the corresponding converter algorithm A and then entered in the trend characteristics map T _c for further trend analysis according to one of the methods described above.

Reference List

1

oil filter system

1B

operating oil

1F

oil filter

1M

Oil differential pressure measuring device

10

control and regulation device

10.1

map module

10.2

analysis module

1L

oil line

100

internal combustion engine

101

engine

102

air duct systems

103

heat exchanger

104

oil control system

ECU

engine control unit

A

converter algorithm

W

converter module

B

operating parameters

D

sensor data

K

Map, standard map

X

detail

SW

threshold

R, R1, R2, R3 ... Ri

relation size, relation size values, further relation size value

S

sensor system

S1

first pressure sensor

S2

second pressure sensor

p1

first oil pressure

p2

second oil pressure

E, Eg, E1

Trend development, long-term trend development, short-term trend development

T, Ta, Tb, Tc

Trend box, first, second, third trend box with developing trend curve to determine a trend deviation ΔT

TK, TK1, TK2

Trend curve, previous and further trend curve ok jr

toil

oil temperature

TB

confidence level

oil

oil parameters

MOT's

engine parameters

hB

operating time

Hi

operating time point in time

M

load point

MMOT

engine torque

nMOT

engine speed

bp

operating parameters

Δp1, Δp1, Δp2, Δp3

Mean value of the oil pressure difference Δp _i for the relation variable R

Δ, ΔT

Deviation Trend deviation

ΔTg

global trend deviation

ΔT1

local trend deviation

Δpi

oil pressure difference

Go

upper limit development

Gu

lower limit development

Z, Z1, Z2, Z3, Zi

Value of an operating time point in time h _i , i=1, 2, 3, at which the relational variable values Ri are determined

t1

Earlier expected time, individual part ordering time up to the "Limit Yellow"

t2

Late expected time, individual part ordering time up to the "Limit Red"

EIT

Time of order for an individual part in "Case 1"

ET2

Time of order for an individual part in "Case 2"

O

Run-in time offset

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 3519026 [0007]
• DE 102007048182 B3 [0009]

Claims (24)

Method for detecting an oil condition of an operating oil in an engine (101) of an internal combustion engine (100), in particular for a diesel, Otto or gas engine, the internal combustion engine having: - an oil control system (104) with an oil filter (1F) for the operating oil (1B) and an oil differential pressure measuring device (1M) designed to detect an oil pressure difference (Δp _i ) or similar oil pressure relation of the operating oil via the oil filter (1F) in the oil supply system (104), - a control and/or Control device (10), in particular for controlling and regulating the internal combustion engine, with an analysis module (10.2) for the oil differential pressure (Δp _i ), wherein - the oil differential pressure (Δp _i ) in relation to an operating time (h _B ) of the internal combustion engine is processed in the analysis module (10.2), characterized in that - a number of relational variable values (R ₁ , R ₂ , R ₃ , R _i ) taking into account the oil differential pressure (Δp _i ) in relation to a number of operating time points in time (hi) given en - the number of relational values (R ₁ , R ₂ , R ₃ , R _i ) is assigned to a trend development (E) over the operating time points (hi), and - for another to the number of operating time points ( hi) additional time in service (hi) a further relational variable value (R _i+1 ) in relation to a relevant trend deviation (ΔT) from the trend development (E) caused by at least one further relational variable value (R _i+1 ) is analyzed, in particular by means of a changed trend development. procedure after claim 1 , characterized in that the relevant trend deviation (ΔT) results as a decrease in the trend development by means of the changed trend development, in particular as a decreasing trend deviation, in particular as a contribution below a normal trend development as the relevant trend deviation (ΔT) from the trend development ( E) is analyzed. procedure after claim 1 or 2 , characterized in that - a trend development (E) in the form of a first variant of a normal trend development over the operating period (h _B ) is increasing, in particular monotonically increasing, preferably in a diesel or Otto engine, in particular with the trend deviation as a decrease in trend development is recognizable as a changed trend development, or - a trend development (E) in the form of a second variant of a normal trend development over the operating period (h _B ) remains the same or decreases, in particular decreases monotonically, preferably in the case of a gas engine, in particular where the trend deviation is recognizable as an increase in the trend development as a changed trend development. Procedure according to one of Claims 1 until 3 , characterized in that - the further relational variable value (hi) is below the current trend development (E), in particular the previous trend curve (TK), and/or below a normal trend development, and/or - the slope of a relevant trend development (E ), in particular a further trend curve (TK2), with the further relational value (Ri) in comparison to the current trend development (E), in particular previous trend curve (TK), decreases, and/or decreases or increases in comparison to a normal trend development decreases, in particular a positive gradient value decreases or becomes negative or a negative gradient value continues to decrease. Procedure according to one of Claims 1 until 4 , characterized in that the further relational variable value (R _i+1 ) in relation to a relevant trend deviation (ΔT) from the trend development (E) caused by at least one further relational variable value (R _i+1 ) by means of the changed trend development is analyzed over time to determine a rate of trend deviation. Procedure according to one of Claims 1 until 5 , characterized in that - the time extent and/or amplitude, in particular the ramp, of the trend deviation (ΔT) from the trend development (E) is analyzed when the trend development changes and/or - a trend signature of the decreasing trend deviation (ΔT) is recognized as the relevant trend development for which the time extension, in particular ramp, has a finite value above zero and up to a maximum of a few hours, in particular above 5 minutes and up to ten hours. Method according to one of the preceding claims, characterized in that the relevant trend development (E) of the relation variable is stored by a filter model while processing the oil pressure relation, in particular the first and second oil pressure, by means of a relation variable (R) taking this into account to an operating time (h _B ) of the internal combustion engine, with the relevant trend development (E) of the relational variable being discriminated using the filter model, in particular to distinguish between a relevant effect of oil aging and oil dilution as a comparatively rapid but not sudden trend signature of a relevant trend development (E) from other effects. procedure after claim 6 , characterized in that the relevant trend development (E) of the relation variable, in particular with regard to oil aging and/or oil dilution, the decreasing trend signature of which is superimposed in the trend by an increasing normal trend development, is discriminated by means of the filter model relating to one or several trend signatures for a running-in period of the engine, a filter change and/or an oil refill, in particular for - a running-in period of the engine, whereby a trend signature of a running-in period is not taken into account in the trend in the service life, - a filter change, with a suddenly decreasing or increasing trend signature in trend is followed by a re-statement of trend development, - an oil replenishment where an oil replenishment trend signature is suddenly increasing or moderately increasing. Procedure according to one of Claims 1 until 8th , characterized in that the oil differential pressure measuring device (1M) has a first pressure sensor (S1) arranged in the direction of flow before the oil filter and a second pressure sensor (S2) arranged in the direction of flow after the oil filter, optionally an override valve of an oil pressure maximum control, and the method , in particular taking into account the maximum oil pressure control, has the further step: - detecting and indicating a first oil pressure (p1) upstream of the oil filter using the first pressure sensor and a second oil pressure (p2) downstream of the oil filter using the second pressure sensor, wherein - the first and second oil pressure (p1, p2) is processed by means of an oil pressure relation of the operating oil via the oil filter (1F) in the oil supply system (104), in particular as an oil pressure difference (Δp _i ), which takes this into account. Procedure according to one of Claims 1 until 9 , characterized in that - the oil pressure relation, in particular the oil differential pressure, is recorded in relation to a number of operating parameters (B) of the engine and/or oil parameters of the operating oil in a map (K), and/or- a standard - map (K) of standard differential pressures for a standard engine and/or a standard operating oil is established in relation to a number of operating parameters (B) of the engine and/or oil parameters of the operating oil. Procedure according to one of Claims 1 until 10 , characterized in that the oil pressure relation, in particular the oil differential pressure, in particular a first and second oil pressure (p1, p2), is converted to a normalized oil pressure relation, in particular to a normalized oil differential pressure, in particular by means of a standard Map (K) of standard differential pressures in relation to a number of operating parameters (B) of the engine and/or oil parameters of the operating oil. Procedure according to one of Claims 1 until 11 , characterized in that - for each relation variable value (R ₁ , R ₂ , R ₃ , R _i ) at an operating duration time (hi) a number of oil pressure relations of the second and first oil pressure (p1, p2) is formed , in particular the differential oil pressures (Δp _i ) of the second and first oil pressure (p1, p2) are formed, and/or - for an oil pressure relation, in particular a differential oil pressure (Δp _i ), a normalized relation variable value (R ) is formed and/or a normalized second and first oil pressure (p1, p2) is formed for the second and first oil pressure (p1, p2), in particular by means of a standard characteristic map (K). procedure after claim 11 or 12 , characterized in that - for an operating time point in time (hi), the normalized relation variable value as a quotient of the oil pressure relation, in particular the oil differential pressure, and an associated variable of the characteristic map (K) and/or standard characteristic map, in particular a standard size, is formed at an operating parameter (B) of the engine and/or oil parameter. Procedure according to one of Claims 11 until 13 , characterized in that a normalized relation variable value for an oil pressure difference is formed by means of a converter algorithm (A) assigned to the engine for the normalized relation variable value (Ri) for the operating time point in time (hi), in particular the converter algorithm (A) has a quotient, averaging and/or integration by means of a standard characteristics map (K) of standard differential pressures in relation to a number of operating parameters (B) of the engine and/or oil parameters of the operating oil. Procedure according to one of Claims 1 until 14 , characterized in that the operating parameters (B) of the engine and/or oil parameters of the operating oil include an engine speed (n _MOT ) and an operating oil temperature (T _oil ). Method according to one of the preceding claims, characterized in that - the trend deviation (ΔT) is evaluated by means of a deviation determination, in particular a difference formation, and/or - it is recognized that the trend deviation is significant, in particular a status signal is output which indicates a significantly degraded oil condition. Method according to one of the preceding claims, characterized in that a short-term trend development (E ₁ ) is analyzed in such a way that a temporally local trend deviation (ΔT ₁ ) of the further relation variable value (Ri) itself in relation to the normal Trend development, in particular previous trend curve (TK1), is analyzed. Method according to one of the preceding claims, characterized in that a long-term trend development (E _g ) is analyzed in such a way that a temporal global trend deviation (ΔT _g ) of a trend development determined with the further relation variable value, in particular further trend curve (TK2), to the previous trend curve (TK1) present at the time of operation is analyzed. Method according to one of the preceding claims, characterized in that for a normal trend development - an upper limit development (G _o ) and a lower limit development (G _u ) are specified, and/or - an earlier and a later expected time (t1, t2) is specified for a status signal. Control and/or regulating device (10), in particular for controlling and/or regulating an internal combustion engine (100), for detecting the oil condition of an operating oil (1B) for an engine (101) of the internal combustion engine, in particular for a diesel, Otto or Gas engine, wherein the control and regulating device has a map module (10.2) and an analysis module (10.1) for a differential oil pressure and is designed, a method according to one of Claims 1 until 19 to execute. Control and / or regulating device (10) after claim 20 , characterized in that the control and regulating device (10) comprises: - the analysis module (10.1) for the oil differential pressure (Δp _i ) or similar oil pressure relation considering relation variable values (R ₁ , R ₂ , R ₃ , R _i ) in relation to a number of operating time points in time (hi), which is designed to process the oil differential pressure (Δp _i ) in relation to an operating time (h _B ) of the internal combustion engine and has: - an operating recorder and converter (W) in which a number of relational variable values taking into account the oil differential pressure (Δp _i ) is specified in relation to a number of operating time points in time, characterized by - a trend generator by means of which the number of relational variable values (R ₁ , R ₂ , R ₃ , R _i ) is assigned to a trend development, - a deviation generator by means of a further relation variable value (R _i+1 ) in relation to a by means of at least de s a further relation variable value (R _i+1 ) caused trend deviation (ΔT) from the trend development (E) is analyzed, in particular by means of a changed trend development. Control and / or regulating device (10) after claim 20 or 21 , characterized in that - the deviation generator is designed to evaluate the trend deviation by means of a deviation determination, in particular a difference calculation, and/or - a signal transmitter is designed, in the event that the deviation is significant, to output a status signal that indicates a significant indicates impaired oil condition. Control and / or regulating device (10) according to one of claims 20 until 22 , characterized in that - the relevant trend deviation (ΔT) results as a decrease in the trend development by means of the changed trend development, in particular as a decreasing trend deviation, in particular a contribution below a normal trend development as the relevant trend deviation (ΔT) from the trend development (E) is analyzed, and/or - the further relational value (R _{i +1} ) in relation to a relevant trend deviation (ΔT) from the trend development (E ) is analyzed over time by means of the changed trend development in order to determine a speed of a trend deviation. Internal combustion engine (100) with an oil supply system (104) comprising an oil filter for the operating oil and an oil differential pressure measuring device (1M), in particular with a first pressure sensor arranged upstream of the oil filter in the direction of flow and a second pressure sensor arranged downstream of the oil filter in the direction of flow, the is designed to - detect and indicate an oil pressure difference (Δp _i ) or a similar oil pressure relation of the operating oil via the oil filter (1F) in the oil routing system (104), in particular a first oil pressure upstream of the oil filter by means of the first pressure sensor and a second oil pressure downstream the oil filter by means of the second pressure sensor, wherein - the internal combustion engine has a control and/or regulating device according to one of claims 20 until 23 having.

Images