DE102007059614B3 - Method for examination of blockage degree of jet arrangement of equipment, involves determining point of time for examination of blockage degree as function of parameter of characteristic of temporal use characteristic - Google Patents

Abstract

The method involves determining point of time for examination of the blockage degree as a function of parameter of characteristic of a temporal use characteristic of the jet arrangement and another parameter of characteristic of operating condition of the equipment. A blockage value is assigned to each use of the jet arrangement, and blockage values are is added to a blockage account, and the examination of the blockage degree is initiated if the blockage account exceeds a certain threshold value. An independent claim is included for a device with a jet arrangement.

Description

The The present invention relates to a method for checking the Degree of clogging of a nozzle arrangement, in particular a misting nozzle arrangement, a cooking appliance and a device for implementation of such a procedure.

Cooking appliances, especially for the large kitchen, which can be operated with hot air, steam or in combination with hot air and steam, can also work using a Beschwadungsdüse for Beschwadung of food and are well known to those skilled. As an example, only on the EP 0 386 862 B1 directed.

One Humidification process regularly sets this at least partially convicting Water from its liquid in the vaporous State ahead. Due to the fact that at higher temperatures in conventional Water present bicarbonate reduced in favor of the carbonate content, one observes depending on the degree of hardness the water a more or less pronounced precipitation of carbonates, as well Calcification known. This calcification can be used with cooking appliances, coffee, Dishwashers or washing machines the functionality significantly affect. Accordingly missing it is also not commercially available Descaling. However, such usually quite aggressive Descaling agent is not unnecessary to use often and to check the functional state of said household appliances to be able to Meanwhile, a wide variety of devices are used, indicate or monitor the degree of calcification of household appliances to help.

So revealed the DE 102 13 014 B4 a device and a method for monitoring the degree of clogging of a Beschwadungsdüse in a cooking chamber of a cooking appliance. Accordingly, a determination of the degree of clogging can take place in that during and / or after a Beschwadungsstoß the time course of the temperature and / or humidity in the cooking chamber is or are received by means of suitable sensors. From the data thus obtained, the slope of the temperature drop and / or rise after the beginning of a steaming is determined in a detection and evaluation unit of the cooking appliance. In this case, a small slope of the temperature drop or a temperature rise is an indication of the presence of an at least partially clogged or calcified Beschwadungsdüse. In the detection and evaluation unit, the determined slope of the temperature drop and / or increase is compared with a predetermined reference value, wherein when a certain deviation from the reference value is exceeded, a signal is transmitted to a display unit of the cooking appliance, thereby releasing, for example, an optical and / or audible warning signal becomes. Also proposed is with the DE 102 13 014 B4 a method for decalcifying a Beschwadungsdüse, which includes in particular the use of ultrasonic waves.

However, this prior art has significant disadvantages. So according to the in the DE 102 13 014 B4 described a method of checking the degree of clogging typically at regular, predetermined intervals instead. On the one hand, this leads to the fact that too frequent a check of the degree of clogging itself contributes to the formation of additional limescale deposits due to the necessary amount of mistification, whereby in addition water and energy are unnecessarily consumed. On the other hand, especially with intensive use of the Beschwadungsfunktion a cooking appliance, too rare a check of the degree of clogging that a possible clogging or calcification of the Beschwadungsdüse is detected too late, so that no timely measures for cleaning or decalcification of the nozzle can be performed more.

From the not pre-published DE 10 2007 005 501 The applicant is also aware of a method of cleaning soiled or calcified surfaces of an interior or steam generator in a food processing apparatus. During operation of the food processing device so-called dirt spots are calculated depending on measured variables, such as the temperature, which are summed up to a dirt account. According to the described method, a cleaning process in the food processing device is performed when a certain value for the dirty account is exceeded.

It The object of the present invention is a method for checking a Degree of clogging of a nozzle arrangement a cooking appliance which overcomes the disadvantages of the prior art. Especially a method should be provided which depends on the current operating conditions of the cooking appliance and the individual Usage behavior of a user determining an optimal Time to review the Clogging degree of a water-carrying nozzle allows.

These Task is solved through a procedure for reviewing a Degree of clogging of a nozzle arrangement a cooking appliance, the time to review the Degree of clogging depending on at least one for at least one temporal utilization characteristic of the nozzle arrangement characteristic first size and at least one for at least one operating condition of the cooking device characteristic second Size determined being, each using the nozzle assembly a clogging value is assigned, clogging values to one Clogging account will be added and checking the degree of clogging is then initiated when the constipation account has a specific Threshold exceeds.

there It is preferably provided that the nozzle arrangement of at least a nozzle, at least one valve and at least one line is constructed, and the first size determined is from the duration of the opening the valve and / or the time between two consecutive openings of the valve.

According to one another embodiment is provided that the nozzle assembly as a misting nozzle assembly designed for Beschwadung of food in a cooking chamber of the cooking appliance is determined, and the first size becomes from the temporal consequence of Beschwadungsereignissen.

there can be provided that a Beschwadungsereignis a single Corresponds to a splash being the first size through the duration of the humidification stroke and / or the pause time determined between two consecutive humidification surges becomes.

With The invention also proposes that a humidification event corresponds to a Beschwadungsintervall, the first size by the humidification time of the humidification interval resulting from the Sum of the duration of each hum incident within the humidification interval results, and / or the pause time between two consecutive Humidification intervals is determined.

Further is proposed by the invention that for each Beschwadungsereignis in dependency of Humidification duration and / or pause time Blockage values, such as in the form of calcareous points.

According to one another embodiment can be provided that the second size is determined by the Cooking chamber temperature, the humidity in the oven, the degree of hardness of the nozzle assembly adjacent water, the pressure of said water and / or the species of dissolved in said water Lime, and / or the second size determined is characterized by a temporally variable third size, determined through the oven temperature and / or the humidity in the oven, and / or the second size is determined is determined by a time constant fourth size, determined by the degree of hardness at the nozzle assembly adjacent water, the pressure of said water and / or the species of dissolved in said water Lime.

there can also be provided that the Lime points with a lime factor determined by the second size be weighted.

in this connection it is preferred that the Lime points before adding up to a blockage account in the form of a lime account multiplied by a first lime factor resulting from the third size calculated and / or the Lime Account Threshold of a second Liked Factor depends which is calculated from the fourth size.

With the invention is also proposed that the constipation account after Achieving the threshold and / or achieving a predetermined Operating state of the cooking appliance, reset to zero.

there it is preferred that the clogging account after cleaning and / or Descaling at least the nozzle assembly reset to zero becomes.

Further can be provided that when reviewing the Constipation a detected Degree of clogging with stored, previously measured and / or calculated Reference values is compared and depending on the result of the Compare the allocation of the calcification points to the first size and / or the first and second Kalkfaktoren adapted to the third and fourth size will or will be.

It can also be provided that in the case in which the threshold is not reached after a certain time, such as a month or the like, and / or after a certain operating time of the cooking appliance or the nozzle arrangement, such as 100 operating hours, still the degree of clogging checked becomes.

With The invention also provides a device with a nozzle arrangement, comprising at least one nozzle, at least one conduit and at least one controllable valve, wherein the nozzle at least partially arranged in a cooking chamber of a cooking appliance is the line connected to a water network of the cooking appliance and that Valve with a control or regulating device of the cooking appliance in operative connection stands, and with at least one measuring device for checking the Degree of clogging of the nozzle assembly, wherein the measuring device at least a first sensor for detecting the first size, at least a second sensor for detecting the second size and / or at least a third sensor for detecting the degree of clogging comprising, in operative connection with the control or regulating device stands or stand, and the control or regulating device for performing a Procedure is designed so that the time to review the Constipation degree depending on from at least one for at least one temporal utilization characteristic of the nozzle arrangement characteristic first size and at least one for at least one operating condition of the cooking device characteristic second Size determined being, each using the nozzle assembly a clogging value is assigned, clogging values to one Clogging account will be added and checking the degree of clogging is then initiated when the constipation account has a specific Threshold exceeds, and a display device for the first size, the second Size that Constipation values, the constipation account and / or the degree of clogging is provided.

there it is preferred that the nozzle arrangement a Beschwadungsdüsenanordnung includes.

Of the The present invention is therefore based on the surprising finding that that based on the recording of temporal usage characteristics a nozzle arrangement a cooking appliance and the operating conditions of the cooking appliance an optimal time to review the Degree of clogging of the nozzle assembly, which a nozzle, a supply line for Water and one between the nozzle and the supply line disposed valve comprises, are determined can. In general, the temporal usage characteristic of the nozzle arrangement is at least determined by the time sequence of turn-on times and / or Pause times of the nozzle, while the Operating conditions of the cooking appliance at least by the oven temperature, the humidity in the oven, the Pressure at the nozzle water, the degree of hardness said water and / or the type of lime dissolved in said water are determined.

According to the invention is at every nozzle usage a clogging value depending on the temporal usage characteristics of the nozzle assembly and the operating conditions of the cooking appliance calculates the degree of progressive clogging of the nozzle assembly displays. The optimal time to check the degree of clogging is reached when the clogging value exceeds a certain threshold. Once the threshold has been reached, the degree of clogging is checked the nozzle, after which the threshold is reset to zero. So on the one hand be prevented by a too frequent review of the Constipation an unnecessary Calcification of the steaming nozzle takes place while on the other hand, it is ensured that this check is carried out frequently enough, to blockage or calcification of the Beschwadungsdüse in a timely manner to detect.

Should If the threshold is not reached, the check for Safety anyway after a certain time, for example after one month or after 100 operating hours, since the last one reset the threshold to zero.

in the concrete case of a Beschwadungsdüse is their temporal usage characteristics determined by a temporal sequence of humidification events, d. H. of individual smoke bursts or humidification intervals, which include multiple humidification surges can. While a single stroke of humility temporally by its duration, thus by the Beschwadungsdauer, and the break time characterized to the previous Beschwadungsstoß is, corresponds to the Beschwadungsdauer a Beschwadungsintervalls the sum of the duration of the individual humidification surges within the humidification interval and the pause time of the time between two successive humidification intervals. In other words, the temporal usage characteristics of the humidifying thus determined by the temporal sequence of the Beschwadungsdauer and the pause time between successive humidification events.

The main part of a possible blockage of the Beschwadungsdüse and / or the supply line is determined by their calcification. Therefore, the clogging value is referred to as the lime value, or better, the lime point, the sum of all clogging values as the lime account, and its threshold value as the lime account threshold. More specifically, according to the invention, each calorific event is subject to calcification depending on the duration of the summon time and the break time of the summon event, ie the individual Be or the steaming interval, and weighted with calcification factors determined by the operating conditions of the cooking appliance. The weighted calcification points are then added up to a lime account. With each humidification event, therefore, the lime account increases, which thus indicates the degree of progressive calcification of the steaming nozzle.

• i.) Beschwadungsdauer und Pausenzeiten-Kalkpunkte Die Stärke der Verkalkung einer Beschwadungsdüse ist nicht nur abhängig von der Anzahl der Beschwadungsstöße oder Beschwadungsintervalle, sondern auch von den Pausenzeiten zwischen aufeinanderfolgenden Beschwadungsstößen oder Beschwadungsintervallen. So ist beispielsweise bei einem einzelnen Beschwadungsstoß pro Stunde eine stärkere Verkalkung als bei einer sich alle 5 Minuten wiederholende Folge von fünf Beschwadungsstößen zu erwarten. Ein besonders kurzer Beschwadungsstoß mit einer langen, darauffolgenden Beschwadungspause stellt dabei den ungünstigsten Fall dar, bei dem die Beschwadungsdüse am schnellsten verkalkt. Das nach dem Beschwadungsstoß an den Innenwänden der Düse verbleibende Wasser hat nämlich genügend Zeit, vollständig zu verdampfen und Kalkrückstände zu hinterlassen. Eine deutlich geringere Verkalkung ist bei sehr langen Beschwadungsstößen in Verbindung mit kurzen Pausenzeiten zwischen diesen zu erwarten, da während des langen Beschwadungsstoßes Verunreinigungen und Kalk mit dem Wasserstrom durch die Düse mitgerissen werden können. Die für ein Beschwadungsereignis vergebenen Kalkpunkte sind somit abhängig von der Beschwadungsdauer und der Pausenzeit zwischen jeweils dem letzten und dem aktuellen Beschwadungsereignis.
• ii.) Garraumtemperatur-Kalkfaktor Da die Verdunstungs- und Verdampfungsrate von Wasser mit steigender Temperatur zunehmen, ist bei steigender Temperatur auch eine höhere Verkalkungsgeschwindigkeit der Beschwadungsdüse zu erwarten. Die momentane Temperatur der typischerweise aus einem Metall ausgebildeten Beschwadungsdüse ist nicht nur von der Garraumtemperatur, sondern auch von der Menge des die Düse durchfließenden Wassers abhängig, welches direkt aus dem Hauswassernetz kommend einen typischerweise kühlenden Einfluß auf die Beschwadungsdüse hat. In Abhängigkeit der Garraumtemperatur GT kann somit ein Gewichtungsfaktor oder auch Kalkfaktor KF_GT bestimmt werden, mit dem die zuvor berechneten Kalkpunkte multipliziert werden.
• iii.) Wasserhärtegrad-Kalkfaktor Unter dem Härtegrad von Wasser wird der Anteil an Calciumcarbonat bzw. Kalk an einer Volumeneinheit Wasser verstanden. Ein höherer Härtegrad des verwendeten Wassers hat eine höhere Verkalkungsgeschwindigkeit der Beschwadungsdüse zur Folge. Bei der Berechnung der Kalkpunkte kann der Einfluss des Härtegrades durch die Einführung eines entsprechenden Kalkfaktors KF_H berücksichtigt werden.
• iv.) Art des Kalks-Kalkfaktor Weltweit existieren unterschiedliche Kalkarten, die im jeweiligen Wasser gelöst sind. Die Angabe des Härtegrades gibt dabei lediglich an, wieviel Kalk, jedoch nicht welche Art von Kalk im Wasser gelöst ist. Da jede Kalkart ein spezielles Ausfallverhalten aufweist, kann beispielsweise eine Anpassung des Kalkkonto-Schwellenwertes an unterschiedliche Kalkarten durch Vergleich des bei einer Überprüfung erfassten Verstopfungs- oder Verkalkungszustandes der Beschwadungsdüse mit in einer Steuer- oder Regeleinrichtung des Gargerätes gespeicherten Referenzwerten für den bei verschiedenen Kalkarten zu erwartenden Verstopfungs- oder Verkalkungszustand erfolgen.
• v.) Wasserdruck-Kalkfaktor Die Beschwadungsvorrichtung des Gargerätes ist an ein Wassernetz angeschlossen, welches je nach Aufstellungsort des Gargerätes einen unterschiedlichen Wasserdruck aufweisen kann. Die Verkalkungsgeschwindigkeit der Beschwadungsdüse und/oder deren Zuleitung erhöht sich dabei, wenn der Wasserdruck P reduziert wird. Generell führt nämlich ein höherer Wasserdruck dazu, daß während eines Beschwadungsstoßes mehr Verschmutzungen und Kalkablagerungen mit dem Wasserstrom mitgerissen werden. Ein höherer Wasserdruck führt demnach zu einer Verringerung der Verkalkungsgeschwindigkeit der Beschwadungsdüse bzw. der entsprechenden Zuleitung und somit zu einem geringeren Kalkfaktor KF_P für den Wasserdruck.

The calcification points and calcification factors assigned to a humidification interval depend on the following factors:

• i.) Humidification time and break-time calcification The degree of calcification of a humidification nozzle depends not only on the number of humidification bursts or humidification intervals, but also on the pause times between successive humidification surges or humidification intervals. For example, a single sweat per hour is expected to cause more calcification than a repeat of every 5 minutes of five swarms. A particularly short burst of humidification with a long, subsequent steaming break represents the worst case, in which the steaming nozzle calcifies the fastest. Namely, the water remaining on the inner walls of the nozzle after the humidification shock has enough time to completely evaporate and leave limescale. A significantly lower calcification is to be expected for very long Beschwadungsstößen in conjunction with short break times between them, as during the long Beschwadungsstoßes impurities and lime can be entrained with the flow of water through the nozzle. The calcification points assigned for a humidification event are thus dependent on the duration of humidification and the pause time between the last and the current humidification event.
• ii.) Cooking chamber temperature-lime factor As the rate of evaporation and evaporation of water increases with increasing temperature, a higher calcination rate of the steaming nozzle is to be expected with increasing temperature. The instantaneous temperature of the typically formed of a metal Beschwadungsdüse not only depends on the cooking chamber temperature, but also on the amount of water flowing through the nozzle, which has a typical cooling effect on the Beschwadungsdüse coming directly from the domestic water network. Depending on the cooking space temperature GT, it is thus possible to determine a weighting factor or lime factor KF _GT with which the previously calculated limescale points are multiplied.
• iii.) Water hardness-lime factor The degree of hardness of water is understood to mean the proportion of calcium carbonate or lime in a unit volume of water. A higher degree of hardness of the water used results in a higher calcination rate of the steaming nozzle. When calculating the calcification points, the influence of the degree of hardness can be taken into account by introducing a corresponding calculation factor KF _H.
• iv.) Type of lime-scale factor There are different types of lime worldwide which are dissolved in the respective water. The indication of the degree of hardness indicates only how much lime, but not what kind of lime is dissolved in the water. Since each type of lime has a special failure behavior, for example, an adaptation of the Kalkkonto threshold value to different types of lime by comparing the detected in a review constipation or calcification state of the Beschwadungsdüse with stored in a control or regulating device of the cooking appliance reference values for the expected at different types of lime Clogged or calcified state.
• v.) Water pressure lime factor The steaming device of the cooking appliance is connected to a water network, which may have a different water pressure depending on the site of the cooking appliance. The calcification rate of the Beschwadungsdüse and / or the supply line increases when the water pressure P is reduced. In fact, a higher water pressure generally causes more pollution and limescale to be entrained in the water flow during a humidification impact. A higher water pressure thus leads to a reduction of the calcification rate of the Beschwadungsdüse or the corresponding supply line and thus to a lower lime factor KF _P for the water pressure.

Further features and advantages of the invention will become apparent from the following description in which an exemplary embodiment of the invention is explained by way of example with reference to a single figure drawing. In this case, the figure shows a characteristic of the course of the temperature-lime factor KF _GT , which can be taken as a basis for a method according to the invention, as a function of the cooking chamber temperature GT.

A humidification nozzle (not shown) is typically connected to a pressurized supply line (not shown) of a cooking appliance (not shown) by means of a controllable valve (not shown). which in turn is connected to a water network (not shown) at the place of installation of the cooking appliance. In a Beschwadungsstoß the valve opens for the duration of Beschwadungsstoßes so that water flows through the Beschwadungsdüse in a cooking chamber of the cooking appliance. After closing the valve, a residual amount of water remains in the Beschwadungsdüse, for example as a water film on the inner surface of the Beschwadungsdüse. This remaining water evaporates and / or evaporates during pauses in the build-up, causing deposits of lime or other substances dissolved in the water in the humidification nozzle. In other words, so a calcification of the Beschwadungsdüse takes place substantially after a Beschwadungsereignis. On the other hand, during the duration of a humidification impact, existing deposits in the humidifying nozzle can be entrained at a sufficiently high flow rate of the water, and an increase in calcification or clogging during the humidification impact is negligible.

In similar Way as with the Beschwadungsdüse is also the calcification of the supply line to Beschwadungsdüse dependent on the humidification time and the pause times between successive humidification surges. During one Beschwadungsstoßes are also here at sufficiently high flow velocity of the water Lime particles entrained in the water flow and through the Beschwadungsdüse inside of the cooking chamber transported. Essentially therefore finds a calcification during the break times the inner surfaces the supply line instead.

• i) die Beschwadungspausen zwischen den Beschwadungsstößen innerhalb eines Beschwadungsintervalls größer als 5 Sek. sind;
• ii) die jeweilige Dauer der Beschwadungsstöße einen Wert von 20 Sek. überschreitet;
• iii) das Beschwadungsintervall mehr als 10 Beschwadungsstöße umfaßt.

As already mentioned above, as an alternative to the allocation of limescale points for each individual impact impact, it is also possible to allocate calcification points for a condensation interval, which may comprise a plurality of condensation impacts. For example, a humidification interval begins with a first hum of impact, with the end of the humidification interval reached when

• i) the humidification pauses between the humidities within a humidification interval are greater than 5 seconds;
• (ii) the duration of the bursts exceeds 20 seconds;
• iii) the steaming interval comprises more than 10 steaming bursts.

Depending on the humidification time of the humidification interval and the pause time between the current and the previous humidification interval, calcification points are assigned to the current humidification interval. For example, the calcification points are weighted with calcification factors for the cooking chamber temperature (KF _GT ), the hardness of the water (KF _H ) and the water pressure (KF _P ) and then added to a lime account.

in the The following section deals in detail with the calculation of these lime factors become.

aufsummiert. Der Wert des Kalkkontos KK ist ein Maß für den Fortschritt der Verkalkung der Beschwadungsdüse seit der letzten Überprüfung des Verstopfungsgrades, die durch Beschwadungsstöße im Verlauf von insgesamt N Beschwadungsintervallen hervorgerufen wird. Dabei errechnet sich KK als Summe der mittels Kalkfaktoren KF_GT(n), KF_H(n) und KF_P(n) gewichteten Kalkpunkte KP bei dem jeweils n-ten Beschwadungsintervall.It is assumed here that, at the time of the last check of the degree of clogging or degree of calcification of the misting nozzle arrangement, the lime account KK was set to zero. It is also conceivable that such a reset has taken place following a descaling of the Beschwadungsdüsenanordnung. In the following first (n = 1) and each further nth humidification interval, in each case calcification points KP (n) are calculated, which are weighted by means of calcification factors KF _GT (n), KF _H (n) and KF _P (n). The thus weighted calcification points of the humidification intervals n = 1... N become the limestone account KK, namely as follows

summed up. The value of the calcification account KK is a measure of the progress of the calcification of the humidifying nozzle since the last check of the degree of clogging caused by humidification shocks over a total of N humidifying intervals. In this case, KK is calculated as the sum of the calcification points KF _GT (n), KF _H (n) and KF _P (n), which are weighted by the calcification factors KF at the nth humidification interval.

1. Lime factor for the cooking space temperature

Table 1 shows the relationship between the lime factor KF _GT and the cooking chamber temperature GT. Accordingly, five different temperature ranges are assigned the lime factors 1 to 5. The temperature ranges with the associated lime factors KF _GT , for example, may have previously been determined experimentally.

The dependence of the lime factor KF _GT on the cooking chamber temperature shown in Tab. 1 is additional graphically in 1 shown. As an alternative to assigning the lime factor KF _GT to different temperature ranges in regions, the experimentally determined values can be approximated with an analytical Fit function.

For example, in 1 a logarithmic fit function KF _{GT, Fit is} plotted, which can be written in the form KF _{GT, Fit} = a · ln (GT) + b with the fit coefficients a = 1.5119 and b = -4.0107. Similarly, polgnome or spline function can also be used as fit functions. Cooking space temperature GT (° C) 0-33 34-134 135-175 176-205 206-300 Lime factor KF _GT 1 2 3 4 5 Table 1: Lime factor KF _GT as a function of the oven temperature GT

2. Water hardness

Table 2 shows the corresponding calcium factors KF _H for the three hardness ranges "soft", "medium" and "hard", which can each be characterized by the concentration of calcium carbonate and the German degree of hardness. The hardness of the water at the place of installation of the cooking appliance can be entered for example by a user via an input device of the cooking appliance or determined by an automatic lime detection system of the cooking appliance, so that on the basis of these data according to the assignment of Tab. 2, the lime factor KF _H can be determined.

As an alternative to calculating a lime factor for weighting the lime points, the degree of hardness can also be incorporated directly into the calculation of the lime points KP for a humidification interval. Calcium carbonate concentration in water (mmol / l) to 1.5 1.5-2.5 over 2.5 German hardness (° dH) 0 to 8.4 8.4 to 14 over 14 hardness range soft medium hard Lime factor KF _H 1 2 3 Table 2: Lime factor KF _H as a function of the degree of water hardness

Since the degree of water hardness at the place of installation of the cooking appliance is generally constant over time, the calcareous account KK can also be scaled directly in accordance with the degree of hardness as an alternative to calculating a lime factor KF _H for weighting the calcification points KP per misting interval. So, starting from an average water hardness (KF _H = 2), if the Kalkkonto threshold is initially 500, the Kalkkonto threshold will decrease to 333 if a hard water hardness (KF _H = 3) is detected in the meantime.

In a further embodiment, the allocation of the lime factor KF _{H can} also take place directly by the use of the value for the German degree of hardness, normalized to 1 ° dH.

3. Water pressure

Table 3 shows the lime factor KF _P as a function of the water pressure P. Thus, a higher water pressure results in a reduced lime factor KF _P for weighting the calcification points KP for a humidification interval. The water pressure of the water network can be detected by a measuring device, which is arranged for example on the steam generator of the cooking appliance. Thus, also any pressure fluctuations of the water network, especially at a poor quality of the water network at the site, be reacted. Alternatively, similar to the degree of hardness, a direct scaling of the Kalkkonto threshold value can take place if the water pressure is constant over time. Water pressure P (bar) Lime factor KF _P to 1.5 3 1.5 to 3 2 above 3 1 Table 3: Lime factor KF _P as a function of the water pressure P

The calculation according to the invention of a lime account represents for the first time a compromise between the frequency of checking a degree of calcification on the one hand and the safety of avoiding calcification on the other. Despite reduced measuring frequency can timely calcification by initiation (for example) one of the DE 102 13 014 B4 known decalcification be prevented.

Claims (16)

Method for checking a degree of clogging a nozzle arrangement a cooking appliance, the time to review the Constipation degree depending on from at least one for at least one temporal utilization characteristic of the nozzle arrangement characteristic first size and at least one for at least one operating condition of the cooking device characteristic second Size determined being, each using the nozzle assembly a clogging value is assigned, clogging values to one Clogging account and verifying the degree of clogging is then initiated when the constipation account has a specific Threshold exceeds. Method according to claim 1, characterized in that that the nozzle arrangement from at least one nozzle, at least one valve and at least one line is constructed, and the first size determined is from the duration of the opening the valve and / or the time between two consecutive openings of the valve. Method according to claim 1 or 2, characterized that the nozzle arrangement as a misting nozzle assembly is formed for Beschwadung of food in a cooking chamber of the cooking appliance, and the first size determined becomes from the temporal consequence of Beschwadungsereignissen. Method according to claim 3, characterized that a humidification event corresponds to a single summon shock, being the first size through the duration of the humidification stroke and / or the pause time determined between two consecutive humidification surges becomes. Method according to claim 3, characterized that a humidification event corresponds to a humidification interval, being the first size through the humidification time of the humidification interval resulting from the Sum of the duration of the individual humidification surges within the humidification interval, and / or the pause time between two successive humidification intervals is determined. Method according to claim 4 or 5, characterized that for each humidification event depending on the duration of the humidification and / or the pause time constipation values, such as in the form of calcareous points, be calculated. Method according to one of the preceding claims, characterized characterized in that the second size is determined by the Cooking chamber temperature, the humidity in the oven, the degree of hardness of the nozzle assembly adjacent water, the pressure of said water and / or the species of the lime dissolved in said water, and / or the second size determined is characterized by a temporally variable third size, determined through the oven temperature and / or the humidity in the oven, and / or the second size is determined is determined by a time constant fourth size, determined by the degree of hardness at the nozzle assembly adjacent water, the pressure of said water and / or the species of dissolved in said water Lime. Method according to claim 6 or 7, characterized that the calcification points with a determining from the second size Lime factor be sealed. A method according to claim 8, characterized in that the Kalkpunkte be added before adding to a constipation account in the form of a Kalkkontos with a first Kalkfaktor, which is calculated from the third size and / or the Kalkkonto threshold depends on a second Kalkfaktor, the calculated from the fourth size. Method according to one of the preceding claims, characterized marked that the clogging account after reaching the threshold and / or reaching a predetermined operating state of the cooking appliance to zero reset becomes. Method according to claim 10, characterized in that that the constipation account after cleaning and / or descale at least the nozzle assembly reset to zero becomes. Method according to one of the preceding claims, characterized that when checking the Constipation degree a detected clogging degree with stored, previously measured and / or calculated reference values becomes and depending of the result of the comparison the allocation of the calcification points to first size and / or the first and second lime factors are adapted to the third and fourth sizes. Method according to one of the preceding claims, characterized characterized in that in the case where the threshold value is after a certain time, such as a month, and / or after a certain time Operating time of the cooking appliance or the nozzle assembly is not reached, yet the degree of clogging is checked. Method according to claim 13, characterized in that that the specific operating time is 100 operating hours. Device with a nozzle arrangement, comprising at least a nozzle, at least one conduit and at least one controllable valve, wherein the nozzle at least partially arranged in a cooking chamber of a cooking appliance is the line connected to a water network of the cooking appliance and that Valve with a control or regulating device of the cooking appliance in operative connection stands, and with at least one measuring device for checking the Degree of clogging of the nozzle assembly, wherein the measuring device at least a first sensor for detecting the first size, at least a second sensor for detecting the second size and / or at least a third sensor for detecting the degree of clogging comprising, in operative connection with the control or regulating device stands or stand, and the control or regulating device for performing a Procedure is designed so that the time to review the Constipation degree depending on from at least one for at least one temporal utilization characteristic of the nozzle arrangement characteristic first size and at least one for at least one operating condition of the cooking device characteristic second Size determined being, each using the nozzle assembly a clogging value is assigned, clogging values to one Clogging account will be added and checking the degree of clogging is initiated when the congestion account exceeds a certain threshold, and a display device for the first size, the second size, the Constipation values, the constipation account and / or the degree of clogging is provided. Device according to claim 15, characterized in that that the nozzle arrangement a Beschwadungsdüsenanordnung includes.