Patent Application
20110114132
The invention relates to a method for operating a ware washer and to a ware washer, in particular commercial dishwasher or utensil ware washer, which is designed as a programmable machine or as a conveyor ware washer.
The invention is aimed particularly at a method for operating a ware washer which is designed as a programmable machine or as a conveyor ware washer and which has at least one pump, a line system connected to the pump and at least one nozzle connected to the line system, wherein a liquid is supplied at least intermittently to the at least one nozzle via the line system while the ware washer is in operation.
Furthermore, the invention relates to a ware washer which is designed as a programmable machine or as a conveyor ware washer and which has at least one pump, a line system connected to the pump and at least one nozzle connected to the line system, wherein liquid is supplied at least intermittently to the at least one nozzle via the line system.
Programmable machines are manually loadable and unloadable ware washers. The programmable machines (called “box-type ware washers” or else “batch dish washers”) may be rack-type push-through ware washers, also called hood ware washers (“hood-type ware washers”), or front loaders (“front loader ware washers”). Front loaders may be built-under machines (“under counter machines”), table top machines (“top counter machines”) or free-standing ware washers with front loading (“free standing front loaders”).
A ware washer designed as a programmable machine usually has a treatment chamber for the cleaning of wash ware. As a rule, beneath the treatment chamber, a washing tank is arranged, in which liquid can flow out of the treatment chamber as a result of gravity. Located in the washing tank is washing liquid which is usually water, to which, if appropriate, detergent can be supplied.
Furthermore, a ware washer designed as a programmable machine has a washing system with a washing pump and with a line system connected to the washing pump and having washing nozzles. The washing liquid located in the washing tank can be conveyed from the washing pump to the washing nozzles via the line system and sprayed through the washing nozzles in the treatment chamber onto the wash ware to be cleaned. The sprayed washing liquid subsequently flows back into the washing tank.
Conveyor ware washers are, in particular, belt-type conveyor ware washers (“flight-type ware washers”) or rack-type conveyor ware washers (“rack conveyor ware washer”). Conveyor ware washers are usually employed in the commercial sector.
In contrast to programmable machines in which the wash ware to be cleaned remains at a fixed location in the machine during cleaning, in conveyor ware washers a transport of the wash ware through various treatment zones of the conveyor ware washer takes place.
A conveyor ware washer usually has at least one prewashing zone and at least one main washing zone which is arranged downstream of the prewashing zone or prewashing zones, as seen in the direction of transport of the wash ware. As a rule, at least one postwashing zone and at least one final rinse zone following the postwashing zone or postwashing zones are arranged downstream of the main washing zone or main washing zones, as seen in the direction of transport. As seen in the direction of transport, either the wash ware received directly on the conveyor belt or the wash ware held by racks usually runs in the direction of transport through an entry tunnel, the following prewashing zone or prewashing zones, main washing zone or main washing zones, postwashing zone or postwashing zones, final rinse zone or final rinse zones and a drying zone into an exit section.
Said washing zones of the conveyor ware washer are assigned in each case a washing system which has a washing pump and a line system (washing line system) which is connected to the washing pump and via which liquid is supplied to the spray nozzles of the washing zone. The washing liquid supplied to the spray nozzles is sprayed in the respective washing zone onto the wash ware which is transported by a transport device of the conveyor ware washer through the respective washing zones. Each washing zone is assigned a tank in which sprayed liquid is received and/or in which liquid for the spray nozzles of the respective zones is provided.
In the conveyor ware washers conventionally known from the prior art, final rinse liquid in the form of fresh water, which may be pure or mixed with further additives, such as, for example, rinsing agent, is sprayed onto the wash ware via the spray nozzles of the final rinse zone. At least part of the sprayed final rinse liquid is transported from zone to zone, opposite to the direction of transport of the wash ware, via a cascade system.
The sprayed final rinse liquid is captured in a tank (postwashing tank) of the postwashing zone, from which tank it is conveyed, via the washing pump of the washing system belonging to the postwashing zone, to the spray nozzles (postwashing nozzles) of the postwashing zone. Washing liquid is rinsed off from the wash ware in the postwashing zone. The liquid which in this case occurs flows into the washing tank of the at least one main washing zone which precedes the postwashing zone, as seen in the direction of transport of the wash ware. Here, the liquid is usually provided with a detergent and sprayed onto the wash ware via the nozzles (washing nozzles) of the main washing zone by means of a pump system (washing pump) belonging to the washing system of the main washing zone. In so far as no further main washing zone is provided, the liquid subsequently flows from the washing tank of the main washing zone into the prewashing tank of the prewashing zone. The liquid in the prewashing tank is sprayed onto the wash ware via the prewashing nozzles of the prewashing zone by means of a pump system belonging to the washing system of the prewashing zone, in order to remove coarse impurities from the wash ware.
Conventionally, ware washers are equipped with rinsing pumps which supply the line system of the final rinse zone with the final rinse liquid to be sprayed. This ensures, in particular, a virtually constant volume flow of the final rinse liquid in the final rinse zone. It is also conceivable, however, to utilize the on-site line pressure, for example the pressure of the fresh water supply, in order to deliver the final rinse liquid to the line system of the final rinse zone. In this last-mentioned instance, an activatable valve may be provided between the line system and the spray nozzles of the final rinse zone, so that a temporary or complete interruption in the supply of final rinse liquid to the spray nozzles can be achieved.
Irrespective of whether the ware washer is designed as a programmable machine or as a conveyor ware washer, commercial ware washers therefore usually comprise at least one pump and/or a valve which ensure/ensures a virtually constant volume flow of the washing liquid or final rinse liquid for the duration of a washing or final rinse process in the treatment chamber (in the case of programmable machines) or in the respective treatment zone (in the case of conveyor ware washers). The respective pumps and/or valves on the line system are switched on and off by means of a control device (machine control) belonging to the ware washer.
However, various operating states of the ware washer, operating errors, insufficient cleaning of the systems or an incorrect installation of washing or final rinse arms (for example, after the cleaning of these) may lead to a deviation in the defined water circulation capacity (flow rate) or to a deviation in the desired washing pressure or desired rinsing pressure or desired nozzle pressure and, consequently, to a change in the washing performance.
The desired washing pressure of commercial ware washers lies in a range of approximately 0.1 to 0.8 bar, depending on the type of machine and its size. The desired final rinse pressure of commercial ware washers is likewise dependent on the type and size of the machine, but usually lies in a range of 0.2 to 0.8 bar. The washing liquid volume flow in commercial built-under machines is approximately 100 to 200 l/min, and in belt-type conveyor ware washers is approximately 400 to 800 l/min. The circulated washing liquid volume flows of hood-type and rack-type conveyor ware washers are between these. In what are known as commercial “Batch Type Dishwasher” machines or programmable machines, a final rinse water quantity of approximately 1.5 to 3.5 l per cycle is consumed. In continuous final rinse processes, as, for example, in conveyor ware washers, the volume flow of the final rinse liquid is approximately 2 to 8 l/min.
The publication EP 1 278 449 B1 relates to a domestic ware washer which has a washing system with an intermittently activated circulation pump and with two rotating spray arms. Furthermore, to detect a fluid pressure prevailing at the pump inlet, a sensor device is provided which is connected to a control device of the ware washer and optionally to an indicator. By the fluid pressure prevailing at the pump inlet being detected, it can be ascertained whether the spray arms of the ware washer are functioning properly. In particular, it can be ascertained whether the free rotatability of the spray arms is blocked, on account of pieces of crockery in the treatment chamber. If such an instance occurs, the intermittent operation of the circulation pump is changed correspondingly so that a predetermined washing result can be achieved.
The publication WO 2004/096006 A2 relates to a ware washer with a washing liquid circuit which is provided with a pressure sensor. It is possible via the pressure sensor to detect whether the hydrostatic pressure of the washing liquid circulating in the washing liquid circuit undershoots a prefixed threshold value. This occurs, for example, when a filter provided in the washing liquid circuit becomes clogged. In such an instance, there is the risk that the wash ware to be cleaned is not treated sufficiently. In order to counteract this, it is proposed to equip the ware washer with an additional washing liquid circuit which is cut in, as required, so that the washing liquid can ultimately be sprayed onto the wash ware with a predetermined desired nozzle pressure.
A method for operating a circulation pump in a program-controlled ware washer is known from the publication DE 197 50 266 A1. The circulation pump is activated intermittently so that pressure fluctuations can be introduced into the washing liquid in a directed manner. This is intended to promote the water flow at a screen, provided in a washing liquid circuit, with the effect of screen cleaning and dirt discharge. In order to prevent the situation where the deliberately introduced instability in the pressure profile is reduced on account of a loading of the washing liquid with foam or on account of the degree of contamination of the washing liquid, there is provision for, with the aid of a pressure sensor, detecting the pressure profile in the circulated washing liquid and, in particular, the absence of pressure fluctuations or of specific measurable pressure peaks. If such an instance occurs, instability is caused in the pressure profile due to an abrupt reduction in the pump rotational speed.
The publication EP 1 008 324 A1 relates to a method for the cleaning of wash ware in a ware washer, in which washing liquid in a washing liquid circuit is sprayed onto a wash ware to be cleaned. In the washing liquid circuit, a pressure sensor is provided, via which the pressure profile of the pump pressure is detected. By means of the detected pressure profile, it is determined whether air is unintentionally sucked in by means of the circulation pump and is therefore in an unstable hydraulic state. In such an instance, the circulation pump of the ware washer is temporarily switched off or throttled.
The set problem on which the present invention is based is to ascertain potential deviations in the water circulation capacity or potential deviations in the flow rate and automatically react correspondingly, in order to counteract the deviation in the water circulation capacity.
In particular, the invention is to achieve the object of providing a ware washer designed as a programmable machine or a conveyor ware washer which has a washing system with a washing pump, with a line system connected to the washing pump and with washing nozzles, potential malfunctions of the ware washer which have or may have an adverse influence on the treatment result being ascertained as early as possible. After potential malfunctions have been ascertained, countermeasures are to be automatically initiated, by means of which a deviation in the defined water circulation capacity or a change in the washing performance can be compensated as early as possible.
Furthermore, the object of specifying a corresponding method for operating such a ware washer is to be achieved.
The solution according to the invention is distinguished in that potential deviations in the volumetric flow rate are detected, using suitable flow sensors, and deviations are communicated via fault warnings to the customer or to the ware washer operator or via a remote control interface to the manufacturing company or to the competent remote maintenance system or are counteracted by means of a change of process parameters.
A suitable flow sensor is a device for sensing the rate of fluid flow. Typically a flow sensor is the sensing element used in a flow meter, or flow logger, to record the flow rate of fluids. As is true for all sensors, absolute accuracy of a measurement requires a functionality for calibration. There are various kinds of flow sensors and flow meters, including some that have a vane that is pushed by the fluid, and can drive a rotary potentiometer, or similar device.
In this case, the invention is based on the recognition that, in a situation where the desired flow rate in the line system is overshot immediately after a pump is switched on, this points to a leak in the line system. By contrast, a high overshooting of the desired flow rate is an indication of a faulty installation of the washing or final rinse arms. If the flow rate lies below the desired flow rate, this is an indicator of blockages in the lines or nozzles.
In particular, according to the invention, there is provision, with the aid of a flow sensor, for detecting the profile of the flow rate of the liquid in the line system and comparing it with a predetermined flow rate profile (the ideal desired flow rate profile, in the fault-free operation of the machine). If there is a deviation in the detected flow rate profile from the predetermined ideal flow rate profile, at least one of the following steps is selected and executed automatically as a function of the type of deviation:
The type of deviation of the detected flow rate profile from the predetermined (ideal) flow rate profile is determined, in particular, by the answers to the following questions:
In the solution according to the invention, therefore, first the type of deviation of the detected flow rate profile from the predetermined (ideal) flow rate profile is determined. Thus, a conclusion as to the cause of the deviation of the detected flow rate profile from the predetermined (ideal) flow rate profile and therefore a conclusion as to the cause of the deviation can be drawn. It is subsequently established whether the deviation, detected via the flow rate profile, may lead to a change in the washing or final rinse performance of the ware washer. Should this be the case, a check is made as to whether there is a possibility of carrying out a regulating action on the operation of the ware washer, so that the potential change in the washing or final rinse performance can be compensated.
Simultaneously with or alternatively to this, as a function of the determined cause of the deviation from the defined water circulation capacity and from in the defined desired flow rate respectively, an optical and/or acoustic fault warning is issued to the machine operator, so that the latter can undertake corresponding measures. This is the case particularly when an operating error is the cause of the deviation from the defined water circulation capacity.
If, by contrast, it is determined that the assistance of external servicing personnel is required in order to eliminate the fault, a corresponding fault warning is issued to a remote maintenance station automatically by the system via a remote control interface of the ware washer. This may be the case, for example, when an insufficient cleaning or final rinse performance of the washing or final rinse system or an incorrect installation of the washing or final rinse arms or a leak in the line system is the cause of the deviation from the defined water circulation capacity and from the defined desired pressure, respectively.
The remote maintenance of ware washers is gaining increasing importance in the support of the hardware and software of ware washers. Due to the ever greater interlinking of the control devices of ware washers via the Internet, to the set-up of in-house intranets and to conventional telecommunication pathways (ISDN, telephone), the possibilities of direct support assistance are extended. Not least because of the possibilities for making savings in travel costs and better resource utilization (personnel and technology), remote maintenance products are used in order to lower costs in businesses. Remote maintenance programs enable the servicing engineer sitting at a distance to have direct access to the control device of the ware washer to be maintained and to carry out corresponding actions.
The invention is described in more detail below with reference to the drawings in which:
a to f show diagrammatic flow rate profiles to explain the principle of the detection of disturbing influences with the aid of the flow rate prevailing in the washing system; and
a to f show diagrammatic flow rate profiles to explain the principle of the detection of disturbing influences with the aid of the flow rate prevailing in the final rinse system.
Said treatment zones 51, 52, 53, 54 of the conveyor ware washer 50 are assigned in each case spray nozzles 13-1, 13-2, 13-3, 13-4, via which liquid is sprayed onto the wash ware which is transported by the conveyor belt 58 through the respective treatment zones 51, 52, 53, 54. At least each washing zone (prewashing zone 51, main washing zone 52, postwashing zone 53) is assigned a tank (washing tank 14-1, 14-2, 14-3), in which sprayed liquid is received and/or in which liquid for the spray nozzles 13-1, 13-2, 13-3 of the respective zones 51, 52, 53 is provided.
The prewashing zone 51, the main washing zone 52 and the postwashing zone 53 of the conveyor ware washer 50 according to the embodiment illustrated in
Further, a control device 20 is provided which serves (inter alia) for suitably activating the respective washing pumps 11-1, 11-2, 11-3 of the washing systems 10-1, 10-2, 10-3 during a washing process, in order at least intermittently to supply liquid via the associated line system 12-1, 12-2, 12-3 to the spray nozzles 13-1, 13-2, 13-3 of the nozzle system belonging to the respective washing system 10-1, 10-2, 10-3.
In particular, in the conveyor ware washer 50 illustrated in
Part of the sprayed final rinse liquid is transported from zone to zone, opposite the direction of transport T of the wash ware, via a cascade system. The remaining part is conducted directly into the prewashing tank 14-1 via a valve 59 and a bypass line 100.
The sprayed final rinse liquid is captured in the tank (postwashing tank 14-3) of the postwashing zone 53, from which tank it is conveyed to the spray nozzles 13-3 (postwashing nozzles) of the postwashing zone 53 via the washing pump 11-3 belonging to the washing system 10-3 of the postwashing zone 53. Washing liquid is rinsed off from the wash ware in the postwashing zone 53. The liquid which in this case occurs flows into the washing tank 14-2 of the main washing zone 52, is usually provided with a detergent and is sprayed onto the wash ware, with the aid of a washing pump 11-2 belonging to the washing system 10-2 of the main washing zone 52, via the spray nozzles 13-2 (washing nozzles) of the washing system 10-2 belonging to the main washing zone 52.
The liquid subsequently flows from the washing tank 14-2 of the main washing zone 52 into the prewashing tank 14-1 of the prewashing zone 51. The liquid in the prewashing tank 14-1 is sprayed onto the wash ware, by means of a washing pump 11-1 belonging to the washing system 10-1 of the prewashing zone 51, via the spray nozzles 13-1 (prewashing nozzles) of the washing system 10-1 belonging to the prewashing zone 51, in order to move coarse impurities from the wash ware.
Each washing system 10-1, 10-2, 10-3 of the conveyor ware washer 50 according to
In the conveyor ware washer 50 illustrated in
In the tank 14-4, liquid is located, which is usually water, to which, if appropriate, detergent or rinsing agent can be supplied automatically in a controlled way by a detergent or rinsing agent metering device, not illustrated in
Like the conveyor ware washer 50 illustrated in
Furthermore, the washing system 10-4 of the ware washer 40 according to
In functional terms, the control device 20 provided in the ware washer 40 according to
It remains to be stated that both the ware washer 40 according to
In the washing system 10 according to
In a conveyor ware washer 50 (for example, according to
Regardless of the question of in which of the respective treatment zones of a conveyor ware washer the washing system 10 according to the illustration in
In contrast to a ware washer 40 (cf.
The washing system 10 illustrated in
The washing pump 11 of the washing system 10 illustrated in
As already indicated, the at least one flow sensor 31 of the washing system 10 belongs to a sensor device 30 which is connected to the control device 20. With the aid of the control device 20, the profile, detected by the flow sensor 31, of the flow rate QI in the washing liquid is supplied to the control device 20.
a illustrates in a diagrammatic and idealized way an “ideal” (desired) flow rate profile QS which is detected by means of the sensor device 30 and which is generated in the washing system 10 during fault-free operation of the ware washer 40, 50.
The switch-on of the washing pump 11, for example on commencement of the washing process, takes place at a time point t0 in the illustration according to
As illustrated in
The (first) time interval Δt1 serves, in the embodiment illustrated in
Preferably, the time interval Δt1 has a set length, which may be a predetermined or predeterminable (e.g., manufacturer, service person or operator programmable or settable) length, the start of the time interval Δt1 being fixed by a time point t1 at which the washing pump 11 is switched on or activated during the washing process in such a way that the washing liquid is supplied to the at least one washing nozzle 13 via the line system 12. As illustrated in
The ideal flow rate QS to be expected in fault-free operation of the ware washer 40, 50 is filed in the control device 20 of the ware washer 40, 50, specifically preferably for each treatment program of the ware washer 40, 50, if different treatment programs are provided for this and if different water circulation capacities and desired flow rates are required for the washing processes of the respective treatment programs, respectively. It is, of course, also conceivable, however, that the ideal flow rate profiles QS to be expected in fault-free operation of the ware washer are not filed in the control device 20 itself, but in a storage device 21 connected to the control device 20, in which case the control device 20 can have access to the storage device 21, as required, in order to read out the flow rate profile QS ideal for the washing process to be carried out.
The ideal flow rate profile QS in the washing system 10 which is to be expected in fault-free operation of the ware washer 40, 50 is preferably filed previously in the control device 20 or storage device 21. It is, of course, also conceivable, however, that the ideal flow rate profile QS is a flow rate profile which has been detected by the sensor device 30 during an earlier washing process and filed in the control device 20 or in the storage device 21. The advantage of this alternative is that, with the aid of the solution according to the invention, it is possible to detect whether or not a particularly slowly occurring deviation of the detected flow rate profile arises in the course of time, as seen over a plurality of washing processes, and this may serve as an indicator of, for example, the degree of contamination of the washing nozzles 13 or as an indicator of the degree of contamination of a filter device provided, if appropriate, in the washing system.
After the flow rate profile QI detected over the time interval Δt1 by the sensor device 30 has been supplied to the control device 20, a comparison takes place between the detected flow rate profile QI and the ideal flow rate profile QS which is filed, for example, in the control device 20 and which is to be expected in fault-free operation of the ware washer 40, 50. If a deviation of the detected flow rate profile QI from the expected flow rate profile QS arises, an analysis of the deviation takes place automatically in order to determine the cause of this and to bring about appropriate countermeasures.
It must be remembered, in this case, that, in determining whether a deviation from the ideal flow rate profile QS is present or not, a certain deviation range has to be taken into account. Preferably, in this case, the control device 20 should be designed in such a way that it finds a deviation from the ideal flow rate profile QS and therefore an operation of the ware washer 40, 50 which is not fault-free, only when the deviation of the detected flow rate profile QI from the predetermined flow rate profile QS overshoots or undershoots a predetermined or predeterminable (e.g., manufacturer, service person or operator programmable or settable) threshold value S0.
It is, of course, also conceivable that the flow rate profile QI detected by the sensor device 30 is averaged, filtered, smoothed or otherwise processed before comparison with the predetermined (ideal) flow rate profile QS.
In the evaluation of the detected flow rate profile QI, and particularly in the comparison of the detected (and, if appropriate, processed) flow rate profile QI with the predetermined ideal flow rate profile QS, it is determined whether a deviation from the ideal flow rate profile QS is present or not. However, the present invention is not restricted only to ascertaining the deviation from the ideal flow rate profile QS; on the contrary, according to the invention, there is provision, in the presence of a deviation of the detected flow rate profile QI from the predetermined flow rate profile QS, for evaluating the type of deviation so that a conclusion as to the disturbing influence responsible for this deviation can be drawn. In the embodiment illustrated, the type of deviation of the detected flow rate profile QI from the ideal flow rate profile QS is to be understood as being, in particular, the size and time gradient of a difference between the predetermined flow rate profile QS (as minuend) and the detected flow rate profile QI (as subtrahend). In particular, not only is the amount of the deviation relevant, but also the question as to whether the detected flow rate QI is higher than or lower than the predetermined flow rate QS, and how the time behaviour of the flow rate profile QI appears.
It is described in detail below, with reference to the illustrations according to
In this case, it must be remembered that, in the illustrations according to
As already indicated, the graph according to
The basic flow rate profile QI illustrated in the graph according to
Alternatively or additionally to this, it is conceivable that the control device 20 also automatically generates a corresponding fault warning and communicates this directly to a remote maintenance station (remote maintenance service) via the remote control interface 23 of the ware washer 40, 50.
As a reaction to the fault warning issued via the optical/acoustic interface 22 and/or via the remote control interface 23, appropriate measures can then be introduced by the ware washer operator or the remote maintenance station in order to compensate the effect of the detected leak on the washing performance of the ware washer 40, 50.
The graph according to the illustration in
In this case, that is to say when the detected flow rate value lies continuously above the predetermined flow rate profile QS and the amount of the difference between the predetermined flow rate profile QS and the detected flow rate profile QI is continuously greater than the second fixed threshold value S2, a major leak in the washing system 10 is concluded automatically by the control device 20 and a corresponding fault warning is issued preferably via the optical and/or acoustic interface 22 of the ware washer 40, 50 in order to draw the attention of the operator of the ware washer 40, 50 to a major leak in the washing system 10.
So that a differentiation can be made as to whether the washing flow rate deviation in the washing system detected in the scenario according to
The graph according to the illustration in
In this case, that is to say when the detected flow rate profile QI lies continuously below the predetermined flow rate profile QS and the amount of the difference between the predetermined flow rate profile QS and the detected flow rate profile QI is continuously greater than a fixed threshold value S0 characteristic of the presence of a deviation, the presence of a blockage in the washing system 10 is concluded automatically by the control device 20. Consequently, a corresponding fault warning is issued automatically, preferably via the optical and/or acoustic interface 22, in order to indicate to the operator of the ware washer 40, 50 that, for example, at least one washing nozzle 13 has to be cleaned.
It is conceivable in this case, that evidence as to the degree of blockage or the number of nozzles to be cleaned can also be obtained by means of the amount of the deviation of the detected flow rate profile QI from the predetermined flow rate profile QS.
The invention is not restricted only to evaluating the detected (actual) flow rate profile QI in the washing system 10 by means of a predetermined (ideal) flow rate profile QS at the commencement of the washing process, that is to say within the first time interval ΔtI, so that conclusions as to possible disturbing influences can be drawn. On the contrary, the solution according to the invention also covers the detection and evaluation of the actual flow rate profile QI during a second time interval Δt2. The second time interval Δt2 may lie in any desired range during the washing process.
In the illustrations according to 4a to 4f, therefore, the flow rate profile QI is not only evaluated in the first time interval Δt1, which preferably lies immediately after the expiry of the adjustment time of the flow rate generated in the line system 12 by the washing pump 11 being switched on, but also in the second time interval Δt2, wherein in the graphs illustrated this second time interval Δt2 commences at the end of the first time interval Δt1 (at the time point t2) and preferably lasts as long as the washing pump 11 is running.
Possible flow rate profiles, from which disturbances or faults occurring during the washing process become clear, are dealt with below with reference to the graphs according to the illustrations in
The graph according to the illustration in
The graph according to the illustration in
In a case when, within a time interval Δt1, Δt2 during which the flow rate profile is detected, the measured volumetric flow rate QI is reduced due to a blockage in the washing system 10 (cf.
In the above-described embodiment of the solution according to the invention, a ware washer 40, 50 is assumed which has at least one washing pump (washing pumps 11-1, 11-2, 11-3 in the conveyor ware washer 50 shown in
Alternatively or additionally to this, however, it is also conceivable, during a final rinse process, to detect the profile QI of the flow rate of the final rinse liquid supplied to the nozzles 13-4, 13-5, 13-6 provided for final rinse and to compare it with a predetermined flow rate profile QS.
In this case, it must be remembered that the conveyor ware washer 50 illustrated, for example, in
The final rinse pump 11-4 of the conveyor ware washer 50 illustrated in
On the other hand, it is, of course, also conceivable, in the ware washer 40 illustrated in
Via the final rinse pump 11-6 connected with its suction side to the outlet of the water heater 60, the final rinse liquid optionally heated in the water heater 60 or unheated can be routed, for example during a final rinse phase, to the final rinse nozzles 13-6 via a final rinse line system 12-6. The final rinse nozzles 13-6 are arranged in the treatment chamber 41, in order to spray the final rinse liquid heated in the water heater 60 onto the wash ware in the treatment chamber 41. It is, of course, also conceivable, however, that the water heater 60 is supplied with pure fresh water, to which a rinse agent is added only after heating in the water heater 60.
The solution according to the invention is not restricted to the presence of a water heater 60. On the contrary, within the scope of the invention, the provision of a water heater 60 may even be dispensed with, so that, during a final rinse process, unheated final rinse liquid is conveyed to the final rinse nozzles 13-6 arranged in the treatment chamber 41 and is sprayed onto the wash ware.
In the embodiment, illustrated diagrammatically in
During a final rinse process, in the embodiment, illustrated diagrammatically in
The final rinse pump 11-6 of the ware washer 40 illustrated in
a to 5f illustrate flow rate profiles which were recorded, in the conveyor ware washer according to
The invention is not restricted to the embodiments shown by way of example in the drawings. On the contrary, the invention may be gathered from an overall consideration by a person skilled in the art of the patent claims and of the description of the exemplary embodiments.
Thus, it is, of course, conceivable that the start of the second time interval Δt2 illustrated in
On the other hand, it is nevertheless conceivable that the profile of the flow rate QI is detected with the aid of the sensor device 30, 30′, 30″, in that the flow rate is measured continuously during the entire washing and/or final rinse process, or in that the flow rate is measured at predetermined or predeterminable time points or events during the entire washing and/or final rinse process, and the measured flow rate values are interpolated.
The solution according to the invention makes it possible automatically to ascertain and evaluate a deviation of the flow rate profile QI prevailing in the washing system and/or final rinse system from an ideal prefixed flow rate profile QS, in order to record disturbances or faults which are responsible for the flow rate deviation and which either are present even at the commencement of the washing process or first arise during the washing or final rinse process. Suitable measures are taken automatically as a function of the type of disturbance, in order either to maintain the desired washing performance of the ware washer or, if this is not possible, to maintain the operation of the ware washer, without entailing the risk of damage occurring on the ware washer.
