Patent Application
20250134342
The present invention relates to a method for operating a dishwasher, a computer program product and a dishwasher.
Conventional dishwashers offer a user different washing programs for cleaning items to be washed. In this context, for example, the different washing programs are optimized for a particular kind of items to be washed, such as glass, plastic, porcelain or metal, a particular degree of soiling or a preferred washing duration. A respective washing program usually comprises a number of steps, which are performed in succession. Typically, for example, these are a pre-washing step, a main washing step, a rinsing step and a drying step. For each of these steps, it is further possible for parameters to be set, such as a duration, an amount of water, a temperature and so on.
EP 3 087 869 A1 discloses a method for washing items to be washed in a program-controlled dishwasher, in which a cleaning, an intermediate washing and a rinsing are performed in succession, wherein the washing step of cleaning begins with an inflow of water, followed by a first washing phase, a water heating phase and a second washing phase, wherein the washing duration of the first washing phase of the cleaning is chosen to be longer than the washing duration of the second washing phase of the cleaning.
EP 2 179 684 A1 discloses a dishwasher with a pre-washing option, which a user can activate in combination with one of the washing programs. When the pre-washing option is activated, the water temperature in the individual steps of the respective washing program and the respective duration thereof is increased, whereby the cleaning performance rises.
Against this background, one object of the present invention consists in improving the cleaning of items to be washed by means of a dishwasher.
Accordingly, a method for operating a dishwasher, in particular a household dishwasher, is proposed. The dishwasher has a control apparatus for performing a washing program from a number of washing programs, wherein a respective washing program comprises a number of sub-program steps, which are performed sequentially when the washing program is performed, wherein at least one particular washing program of the number comprises a sub-program step of pre-washing and a sub-program step of cleaning that follows. The method comprises the performing of the particular washing program, wherein this comprises:
This method has the advantage that, by adding the cleaning agent as early as in the sub-program step of pre-washing, a chemical cleaning effect, which is achieved by cleaning agent dissolved in the washing liquor, already develops during the pre-washing. This increases a chemical integral, which is given for example by the temporal integral of a concentration of chemical substances active in the washing liquor. Overall, the cleaning performance is therefore increased by the pre-washing and thus the cleaning efficiency of the dishwasher is improved.
The control apparatus can be implemented as hardware and/or software. If implemented as hardware, the control apparatus can be embodied for example as a computer, as a microprocessor, such as a CPU (central processing unit), as an application-specific integrated circuit (ASIC) or a programmable logic unit (PLC: programmable logic controller). If implemented as software, the control apparatus can be embodied as a computer program product, as a function, as a routine, as an algorithm, as part of a program code or as an executable object.
The number of washing programs includes, for example, multiple washing programs that differ from one another in the respective sequence thereof. Examples of different washing programs are a standard washing program, an intensive washing program, an economy washing program, a glass washing program and so forth. The intensive washing program aims for a particularly high cleaning performance, for example to this end a temperature of the washing liquor is regulated to a particularly high value and the circulating pump is operated at a particularly high rotational speed. By contrast, the economy washing program for example aims for as low energy and resource consumption as possible, wherein the temperature of the washing liquor is regulated to a particularly low value and for example a running time of sub-program steps of the washing program is extended. It should be noted that the examples above are not exhaustive, but rather only serve as an example to explain different washing programs. A large number of different washing programs can be provided and the washing programs can also be able to be dynamically adapted as a function of detected measurement values, such as an amount of items to be washed, a kind of items to be washed, a degree of soiling and so forth.
The sub-program steps provided according to a respective washing program are in particular performed in a temporally sequential manner. This means, for example, that at any point in time during the performing of the washing program, only one sub-program step is active in each case. Between individual sub-program steps, it can be provided that the washing liquor is partially or fully pumped out and/or the washing liquor is diluted with fresh water, but this is not mandatory. For example, a standard washing program comprises the following sub-program steps in its temporal sequence: pre-washing—cleaning—rinsing—drying. In this standard washing program, the pre-washing takes place for example without heating the washing liquor and without adding cleaning agent. At the end of the pre-washing, the washing liquor is partially pumped out, for example, and at the beginning of the cleaning, the washing liquor is topped up to a particular target volume with fresh water or stored water, for example. Furthermore, the washing liquor is heated to a particular temperature during the cleaning and cleaning agent is dispensed. At the end of the cleaning, the washing liquor is fully pumped out, for example, and water is supplied once again, in order to begin the rinsing. A rinse agent can be dispensed during the rinsing. Depending on the drying technology used, the washing liquor can be heating during the rinsing. If zeolite drying is used, then it is possible to dispense with the heating of the washing liquor during the rinsing. After the rinsing, the washing liquor is fully pumped out, wherein it can also be temporarily stored for use in a later sub-program step or washing program. During the drying, the air in the washing compartment can be circulated, in order to achieve an improved drying. It should be noted that each washing program of the number can comprise the sub-program steps explained above, possibly also in modified form. In particular, the particular washing program can correspond to the standard washing program.
The particular washing program can correspond to any of the washing programs of the number. In particular, each of the washing programs of the number can comprise the sub-program steps of pre-washing and cleaning, as indicated for the particular washing program.
The particular washing program comprises at least the sub-program steps of pre-washing and cleaning. In a conventional washing program, the sub-program step of pre-washing is in particular characterized in that it takes place before the sub-program step of cleaning, wherein the washing liquor is not warmed by means of a heater during the pre-washing. The pre-washing of the proposed method differs from a conventional pre-washing of this kind in that, in the present case, cleaning agent is dispensed during the pre-washing.
The supplied water can comprise fresh water from a supply network and it can comprise stored water, which has been temporarily stored in a previously performed washing program, for example. In particular, water that has been used for rinsing in a previous washing program can be temporarily stored in this manner and reused in the following washing program.
The particular feature of the proposed method lies in the fact that the cleaning agent, which is provided for the cleaning of items to be washed, is dispensed into the washing liquor as early as during the pre-washing, in particular as early as at the beginning of the pre-washing. As already explained in the introduction, it is possible for this to cause a chemical cleaning effect achieved by the cleaning agent to already act at an early stage and thus, with the same duration of the sub-program step, have a longer duration of effect compared to a conventional washing program, in which the cleaning agent is only dispensed in a sub-program step of cleaning.
The circulating of the washing liquor in particular takes place by way of a circulating pump, which for example is arranged in a sump at the bottom of the washing compartment. The circulating pump conveys the washing liquor through a hydraulic system of the dishwasher, for example, which in particular comprises one or more spray apparatuses, such as spray arms or spray nozzles. The washing liquor is output onto the items to be washed at a particular pressure via the spray apparatuses. By way of this application of washing liquor to the items to be washed, the items to be washed are cleaned.
According to one embodiment of the method, one activatable sub-program step of pre-treating is provided which, when it is activated, is performed directly preceding the sub-program step of pre-washing. The pre-treating comprises:
supplying water into the washing compartment of the dishwasher to provide a washing liquor,
In particular, the pre-treating differs from the pre-washing of the particular washing program. In particular, the pre-treating takes place in addition to the pre-washing. The pre-treating takes place in particular without adding a cleaning agent into the washing liquor from a program-controlled dispensing unit. In other words, the washing liquor during the pre-treating is free of cleaning agent added separately from a program-controlled dispensing unit, for example. However, the washing liquor may contain traces of cleaning agent or rinse agent, if it is provided by temporarily stored water from a previous washing program.
In embodiments, cleaning agent can be added before or during the sub-program step of pre-treating. For example, a dispensing unit can have an “open compartment”, which is provided for accommodating cleaning agent and from which the cleaning agent is dispensed into the washing compartment when the door of the dishwasher is closed for example, or the open compartment is shaped such that, when the washing liquor is circulated, the cleaning agent is delivered from the compartment and reaches the washing liquor. This kind of adding corresponds to manually adding cleaning agent and is therefore to be distinguished from the program-controlled adding via the dispensing unit. The cleaning agent can also be dispensed into the washing compartment directly by a user, so that it is already incorporated by the washing liquor during the pre-treating.
“Directly preceding” is understood to mean that the pre-treating takes place immediately before the pre-washing in terms of time. This means that the pre-washing directly follows the pre-treating. Partially or fully exchanging the washing liquor and/or diluting the washing liquor with fresh water can be provided between the two sub-program steps. The sub-program step of pre-treating and the sub-program step of pre-washing can be differentiated from one another, for example, by the washing liquor being partially or fully exchanged and/or diluted during the transition from the pre-treating to the pre-washing.
As the pre-treating is performed with an increased temperature of the washing liquor, the items to be washed located in the washing compartment warm up during the pre-treating. This therefore stores a particular amount of heat, which is released back onto the washing liquor in a later sub-program step, in particular the pre-washing and the cleaning. The result of this is that the washing liquor is warmer during the pre-washing than if the pre-treating is not performed. This effect in particular has advantages if the washing liquor is partially or fully exchanged after the pre-treating.
“Exchanging” is understood in this context to mean that a particular volume of the washing liquor is pumped out by means of a pump and the pumped-out volume is replaced at a later point in time, for example by fresh water. The washing liquor can have a different volume before the pumping-out and after being topped up, i.e. it is not necessary for precisely the volume pumped-out to be replaced, but rather more or less volume can be supplied than what was pumped out. This dilutes the washing liquor, in the sense that a concentration of a dirt load in the washing liquor is reduced. This can contribute to the washing liquor becoming able to absorb dirt. Even in the case of the washing liquor being fully replaced, there is a higher temperature of the washing liquor for the pre-washing compared to the case in which the pre-treating is not performed.
“Diluting” is understood to mean that no washing liquor is pumped out, but rather only additional fresh water is supplied. This increases the volume of the washing liquor. If the washing liquor is diluted, although the absolute amount of dirt in the washing liquor remains the same, the dilution also causes the washing liquor to be capable of absorbing further dirt.
The increased temperature of the washing liquor in the pre-washing produces the advantageous effect that the cleaning agent dissolves particularly well in the washing liquor, i.e. for example dissolves therein particularly quickly and thus can be present in a higher concentration therein more quickly. Thermally activatable components of the cleaning agent, such as enzymes, can also release their effect as early as during the pre-washing due to the increased temperature. The further chemical effects that develop due to the cleaning agent are also pronounced more strongly at an increased temperature; in particular these are accelerated. This is due to most of the dissolving processes being endothermic reactions, for example, the kinematics of which benefit from an increased temperature.
The sub-program step of pre-treating can be activated for example by a user by means of a corresponding input. For example, for this purpose the user actuates a corresponding function key of an operating unit for controlling the dishwasher. The activation can take place for example in an optional manner for any washing program of the number of washing programs.
According to a further embodiment of the method, the step B) of the pre-washing is exclusively performed when the sub-program step of pre-treating has been run through.
This means that the cleaning agent is only dispensed during the pre-washing if the pre-treating has been performed. If the pre-treating has not been performed, the cleaning agent is first dispensed during the cleaning, for example.
According to a further embodiment of the method, this comprises at least partially pumping out the washing liquor between the sub-program step of pre-treating and the sub-program step of pre-washing.
The pumped-out amount of washing liquor is replaced again at the beginning of the pre-washing, by fresh water for example, meaning that the washing liquor has a sufficiently high volume. The sufficiently high volume in particular corresponds to a true running amount that is at least required in order for the circulating pump to run true and for example does not draw in air, which can lead to an increased noise generation and to lower efficiency of the circulating pump.
According to a further embodiment of the method, this additionally comprises the steps:
This has the advantage that as small an amount of the washing liquor as possible is exchanged, which on the one hand reduces water consumption and on the other hand also reduces energy consumption, as the thermal energy stored in the washing liquor remains usable for the further sub-program steps.
The dissolved amount of dirt can also be referred to as dirt load. The dirt load is indicated in the unit of particles/volume or in the unit of grams/volume, for example, wherein the volume refers to the washing liquor. The dirt load can be detected by means of different methods, for example via optical measurement methods that are based on a transmission measurement and/or a light scattering by way of the washing liquor, a conductivity or impedance measurement of the washing liquor, ascertaining a deposit on a filter and so forth. This and further methods for detecting the dirt load are known.
The volume to be pumped out is ascertained for example on the basis of a predetermined threshold value for the dirt load at the beginning of the pre-washing. This means that it is ascertained which portion of the washing liquor has to be pumped out, so that the washing liquor reaches or falls below the predetermined threshold value for the dirt load for a volume predetermined for the pre-washing. In particular, the predetermined volume corresponds to at least the true running amount. The predetermined volume is reached, for example, by the washing liquor being topped up with fresh water.
If the predetermined volume for the pre-washing is the same as the volume during the pre-treating, then the volume pumped out is preferably replaced by supplying fresh water at the beginning of the pre-washing, for example.
According to a further embodiment of the method, the predetermined temperature lies in an interval between 30° C.-70° C., preferably between 40° C.-60° C., further preferably between 50° C.-60° C.
For example, the predetermined temperature amounts to 55° C., wherein the washing liquor is heated to this temperature one time at the beginning of the pre-treating, for example. Following this, the temperature drops slowly on account of thermal losses of the dishwasher due to thermal conduction and thermal radiation.
According to a further embodiment of the method, the cleaning agent dispensed in step B) is a solid cleaning agent.
A solid cleaning agent comprises powder, granulate, pellets or even tablets (tabs), for example. In particular, it may involve a multifunction tab, which comprises multiple different active substances, which in particular are arranged in layers in the tab, so that the different active substances reach the washing liquor at different points in time (specifically only when the outer-lying layers have dissolved).
According to a further embodiment of the method, other than in step B), no further cleaning agent is dispensed into the washing liquor while the pre-washing and the cleaning are being performed.
The dispensing of the cleaning agent in step B) therefore involves the sole program-controlled addition of cleaning agent during the washing program. It should be noted that this does not exclude the addition of a rinse agent during the rinsing.
For example, this involves a dishwasher with a program-controlled dispensing unit, which is configured for adding a single dose of the cleaning agent one time during a respective washing program. The dispensing unit for example comprises a compartment for accommodating the cleaning agent, wherein the compartment is first closed off at the beginning of the washing program, for example by means of a sprung flap, so that there is no contact between the washing liquor and the cleaning agent, and the compartment is opened in a program-controlled manner at an adding time point predefined in the washing program, so that as of this point in time the cleaning agent comes into contact with the washing liquor and can be dissolved by the washing liquor.
According to a further embodiment of the method, a respective sub-program step of a respective washing program is specified by a plurality of parameters with assigned parameter values, wherein the parameter values of the sub-program steps of pre-washing and cleaning of the particular washing program correspond to the parameter values predefined in a standard for ascertaining an energy label determined according to the standard for a particular region.
In Europe, for ascertaining consumption properties of dishwashers, in particular for the ascertaining of an energy consumption, the EN 60436:2020+AC:2020 standard applies for example. This standard contains specifications for a standard measurement method for ascertaining the energy consumption for the dishwasher, wherein the assignment of the energy label for the dishwasher takes place on the basis of the energy consumption ascertained according to the standard. The washing program to be performed according to this standard is also referred to as a label program.
A respective manufacturer of dishwashers is interested in achieving as favorable an energy label is possible, for which reason heating is inactive particularly during the pre-washing in the label program, in order to save energy. Further washing programs, such as an intensive washing program or the like, can deviate from the label program and do not achieve the energy efficiency thereof.
The particular washing program can deviate from the label program, wherein the parameter values for the pre-washing and the cleaning do not correspond to the label program, however. This means that the particular washing program comprises the sub-program step of pre-treating, for example, which is not part of the label program.
According to a further embodiment of the method, a pump rotational speed during the pre-washing and/or the cleaning is reduced compared to a washing program in which the step B) is not performed during the pre-washing, but rather during the cleaning.
This embodiment is particularly advantageous if the sub-program step of pre-treating has been performed before the pre-washing. Due to the increased chemical cleaning performance of the proposed method, the pump rotational speed can be reduced without downgrading the cleaning performance compared to the conventional washing program. Thus, noise emission during the cleaning as well as energy consumption of the circulating pump can be reduced, without downgrading the cleaning performance.
According to a further embodiment of the method, a duration of the sub-program step of pre-washing and/or the sub-program step of cleaning is reduced compared to a washing program in which the step B) is not performed during the pre-washing, but rather during the cleaning.
This embodiment is particularly advantageous if the sub-program step of pre-treating has been performed before the pre-washing. Due to the increased chemical cleaning performance of the proposed method, the duration of the pre-washing and/of the cleaning can be reduced without downgrading the cleaning performance compared to the conventional washing program. It is thus possible to shorten an overall duration of the washing program, without downgrading the cleaning performance.
According to a second aspect, a computer program product is proposed which comprises commands which, on execution of the program by a computer, cause the computer to carry out the method according to the first aspect.
For example, the computer is coupled to a dishwasher and is configured to control it accordingly.
A computer program product, such as for example a computer program means, can for example be provided or supplied as a storage medium such as for example a memory card, USB stick, CD-ROM or DVD, or also in the form of a file which can be downloaded from a server in a network. This can take place for example in a wireless communications network through the transfer of a corresponding file with the computer program product or the computer program means.
According to a third aspect, a dishwasher, in particular a household dishwasher, is proposed. The dishwasher has a control apparatus for performing a washing program from a number of washing programs, wherein a respective washing program comprises a number of sub-program steps, which are performed sequentially when the washing program is performed, wherein at least one particular washing program of the number comprises a sub-program step of pre-washing and a sub-program step of cleaning that follows, and wherein the control apparatus is configured to control the dishwasher with a method according to the first aspect.
The dishwasher has the same advantages as have been explained in relation to the method according to the first aspect. The embodiments and features explained in relation to the method apply accordingly for the proposed dishwasher.
In particular, the dishwasher can have a washing compartment, a hydraulic system with spray apparatuses, a circulating pump, a heater, a dishware basket for accommodating items to be washed, a dispensing unit for adding cleaning agent and so forth. The dispensing unit is in particular configured for adding a single dose of a solid cleaning agent in a program-controlled manner one time.
Further possible implementations of the invention also comprise combinations-not explicitly cited—of features or embodiments described above or below in respect of the exemplary embodiments. In this context, the person skilled in the art will also add individual aspects as improvements or enhancements to the respective basic form of the invention.
Further advantageous embodiments and aspects of the invention are the subject matter of the subclaims and of the exemplary embodiments of the invention that are described below. The invention is described in greater detail below using preferred embodiments with reference to the accompanying figures.
In the figures, elements that are identical or have the same function have been provided with the same reference characters unless otherwise stated.
The door 3 is shown in its opened position in
The household dishwasher 1 also has at least one receptacle for items to be washed 12 to 14. A number of, for example three, receptacles for items to be washed 12 to 14 can preferably be provided, wherein the receptacle for items to be washed 12 can be a lower receptacle for items to be washed or a bottom basket, the receptacle for items to be washed 13 can be an upper receptacle for items to be washed or an upper basket and the receptacle for items to be washed 14 can be a cutlery drawer. As furthermore shown in
Arranged in the door 3 of the dishwasher 1 is a control apparatus 15 and a dispensing unit 16. The control apparatus 15 is configured to perform a washing program SP1, SP1* (see
The sub-program step of pre-washing TP1 comprises at least a supplying of water into the washing compartment 4 of the household dishwasher I to provide a washing liquor. In this context, fresh water or even temporarily stored water from a previously performed washing program can be used. The supply of fresh water is controlled for example by actuation of a valve arranged in a water connection line (not shown). Temporarily stored water can be stored for example in a tank of the dishwasher 1 and let into the washing compartment 4 in this step (not shown). Furthermore, the pre-washing TP1 comprises the dispensing of a predetermined amount of cleaning agent into the washing liquor. The predetermined amount is preferably the amount of cleaning agent filled into the dispensing unit 16 by a user of the household dishwasher 1. The pre-washing TP1 also comprises circulating the washing liquor and applying the washing liquor to items to be washed arranged in the washing compartment 4, for example by means of a circulating pump (not shown). A heater (not shown) for heating the washing liquor is inactive during the pre-washing TP1, so that a temperature of the washing liquor is set on the basis of an initial temperature of the supplied water and the temperature of the items to be washed and the washing compartment 4.
The sub-program step of cleaning TP2 comprises the heating of the washing liquor to a predetermined temperature and the circulating of the heated washing liquor and applying of the heated washing liquor to the items to be washed arranged in the washing compartment 4.
In particular, the control apparatus 15 is configured for performing the washing programs SP1, SP1* explained on the basis of
The washing program SP is started at a point in time t0. First, a pre-washing TP1 is performed. The washing liquor is not heated during the pre-washing TP1, so that the temperature T0 thereof is set on the basis of an initial temperature of the supplied water and the temperature of the items to be washed and the washing compartment 4, and is substantially constant. In this example, the temperature T0 is a room temperature, for example. During the pre-washing TP1, the washing liquor is circulated and thus applied to the items to be washed.
At the point in time t1, the pre-washing TP1 ends and the cleaning TP2 is started. At this point in time t1, the washing liquor is warmed and heated to a target temperature T1. Additionally, cleaning agent DET is added at the beginning of the cleaning TP2, which is marked by the arrow. During the cleaning TP2, the washing liquor is circulated and thus applied to the items to be washed. The temperature of the washing liquor drops slowly in this time period, for example due to thermal losses of the dishwasher 1.
The cleaning TP2 is ended at the point in time t2. In this example, the washing liquor is now fully pumped out. The rinsing TP3 begins, for which purpose fresh water is supplied. During the rinsing TP3, a rinse agent can be added (not shown). During the rinsing TP3, the washing liquor is circulated and thus applied to the items to be washed. Near the end of the rinsing TP3, the washing liquor is heated, in order to bring the items to be washed to an increased temperature, which supports the following drying step TP4. Finally, in the rinsing TP3 the washing liquor is pumped out and there is a transition to the drying TP4.
In the drying step TP4, the items to be washed rest and dry by way of drip-drying and evaporation of the adhering moisture.
The pre-treating TP0 in this context begins at a point in time t0* that lies before the point in time t0. As can be seen from the corresponding temperature progression, the washing liquor is heated as part of the pre-treating TP0, in this example to the temperature T1. During the pre-treating TP0, the washing liquor is circulated and thus applied to the items to be washed. The temperature of the washing liquor drops slowly. At the end of the pre-treating TP0, in this example the washing liquor is fully pumped out. In embodiments, a partial pumping-out can be provided.
At the point in time t0, the pre-washing TP1 begins again, wherein first water is supplied. As the items to be washed and the washing compartment 4 still have an increased temperature, the supplied washing liquor that is supplied in particular at the temperature T0, is warmed up to the temperature T2. This increased temperature T2 of the washing liquor has the advantageous effect that cleaning agent DET added at the beginning of the pre-washing TP1 dissolves more effectively therein and achieves a higher level of effectiveness. The further sequence of the washing program SP1* corresponds to the washing program SP1 in
It is possible to distinguish between the sub-program steps of pre-treating TP0 and pre-washing TP1 on the basis of the composition of the washing liquor, wherein a dirt load of the washing liquor at the end of the pre-treating TP0 is higher than at the beginning of the pre-washing TP1. This is achieved by partially or fully exchanging the washing liquor and/or by diluting the washing liquor with fresh water.
It should be noted that the individual sub-program steps can also have an internal subcategorization, for example into multiple phases. Thus, phases can be provided with different parameter values, for example for the rotational speed of the circulating pump or for setting a water distributor and the like. In the washing programs SP1, SP1*, a partial or full exchange of the washing liquor can take place between two respective sub-program steps. In particular, this can be performed as a function of a dirt load of the washing liquor at a respective point in time. In the drying step TP4, the air in the washing compartment 4 can be circulated and an inner wall of the washing compartment 4 can be cooled down, in order to speed up condensation of moisture. As an alternative to the warming-up of the washing liquor in the rinsing TP3 to heat the items to be washed, a zeolite drying apparatus can furthermore be provided.
It should also be noted that the temperature progressions shown are merely examples and variations therefrom are possible.
The sub-program step of pre-washing TP1 comprises in a first step S1 the supplying of water into a washing compartment 4 (see
It should be noted that the method can comprise further method steps, which are performed temporally before the step S1 or temporally after the step S5. One example of this is formed by additional method steps for performing the sub-program step of pre-treating TP0 (see
Although the present invention has been described with reference to exemplary embodiments, it can be modified in numerous different ways.
T1 temperature value
T2 temperature value
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2022 201 954.7 | Feb 2022 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/083202 | 11/24/2022 | WO |
