EP1945089B1 - Dishwasher and operating method for a dishwasher - Google Patents

Description

The invention relates to a dishwasher, in particular a domestic dishwasher, with a washing container and devices for washing dishes by means of rinsing liquor, wherein the pressure in the devices for washing dishes is adjustable. The invention further relates to a method for operating a dishwasher, in which the pressure in the devices for washing dishes is varied in a wash program section in which dishes are treated with wash liquor.

Such a dishwasher is for example from the US 2004/0079400 A1 known. Therein a dishwasher is disclosed, in which the operating state of a pump is controlled in response to a sensory determined turbidity of the rinsing liquor. In this case, the volume and / or the pressure of the rinsing liquor, with which the dishes to be rinsed is applied, is changed as a function of the turbidity of the rinsing liquor. The pump is configured to accept a plurality of operating conditions with which different flow rates of the flushing fluid can be adjusted at the pump outlet.

A reversing device for influencing the characteristics of the hydraulic arrangement and the circulation pump, in order to allow a greater possibility of variation in the loading of the dishes with rinsing liquor, is in the DE 101 63 184 A1 described. The characteristic of the hydraulic arrangement is changed by changing the flow rate of the liquid through the reversing device and the characteristic of the circulation pump by controlling the rotational speed of the circulating pump.

A dishwashing machine in which the dishes stored in the dishwasher are particularly cleanable depending on the sensitivity and / or the type and / or the intensity of the contamination is described in US Pat DE 198 12 231 A1 described. In this, the speed of a motor of a circulation pump is adjustable. By adjusting the speed, the pressure of the washing liquid can be varied over a wide range. Here, a gentle program is provided, in which the pump motor runs at a lower speed, and which can be selected when sensitive crockery parts are stored in the dishwasher. In contrast, an Interisivprogramm is provided in which the pump motor runs at high speed and the is selectable if heavily soiled dishes are to be cleaned. Alternatively, the pressure can be controlled by means provided in the supply lines to the upper and lower basket valves.

Finally, out of the DE 199 51 839 A1 a water-conducting household appliance is known in which the rotational speed of the circulating pump is influenced by a control device. In this case, a turbidity sensor arranged in the household appliance monitors the cleaning liquid and emits a sensor signal to the control device. Based on this sensor signal, the speed of the circulation pump is set. The adjustment of the pump speed is made to adjust a necessary amount of liquid in the sump so that no air is sucked through the pump.

The dishwashers described in the prior art are based on the common goal of providing dishwashers with the lowest possible water consumption. This is accomplished by adjusting the pressure in the dishwashing devices using the turbidity of the circulated wash liquor as a parameter to adjust the pressure.
From the DE 102 38 303 A1 A method for adjusting a washing program in a dishwashing machine is known, in which the wash program sequence is adjusted on detection of the absence of the addition of rinse aid and during operation of the dishwasher.

It is an object of the present invention to provide a dishwasher and a method for operating a dishwasher, in which the consumption of resources is further optimized.

These objects are achieved by a dishwasher with the features of claim 1 and by an operating method according to the features of claim 9. Advantageous embodiments will be apparent from the dependent claims.

To solve this problem, a generic dishwasher is proposed, in which an adding device is provided for an additive and the pressure in the devices for washing dishes as a function of the addition of the additive in the adding device is adjustable.

This makes it possible to take into account the effect of the aggregate on the behavior of the rinsing liquor. Thus, for example, caused by the additive foaming of the rinsing liquor can be taken into account, which can for example lead to the suction of air through a circulation pump of the dishwasher. However, the suction of air through the circulation pump has the consequence that for the user an increased Noise emission is audible. Such operating conditions can be avoided with the dishwasher according to the invention.

According to a preferred embodiment, the dishwasher has a first sensor device for checking whether the adding device is provided with the additive. If no additive is detected in the adding device, then no additive can be added to the rinsing liquor during a partial program step. The presence of an additive in the adding device thus constitutes a criterion or parameter for influencing the pressure in the dish washing devices.

According to a further embodiment, the dishwasher may have a selection device with which it is possible to set whether and / or in what intensity a metered addition of the additive is to be carried out. While the first variant detects an automatic detection of the presence of additive in the adding device, the user can preselect by the user whether or not metering should be carried out, irrespective of the presence of additive in the adding device Lot to contribute this.

The additive detected presence is according to a further embodiment of the invention, a rinse aid and the adding device is a metering device for the rinse aid. The presence of rinse aid can be used, for example, to decide whether a conventional rinse program or a so-called 3-in-1 rinse program is being performed. The absence of rinse aid in the addition device may be used as an indication that the user is using for convenience convenience a combined drug preparation containing, for example, the ingredients cleanser, softener and rinse aid. However, such a flushing program, which is adapted to a combination preparation, requires a higher energy requirement, which is caused by higher temperatures in a partial program step "rinsing" in order to achieve a satisfactory washing result, in order to achieve a good drying result. This increased energy requirement can be counteracted by the invention by a corresponding adjustment of the pressure, in particular a pressure reduction takes place in the devices for washing dishes in the absence of the additive. This requires one reduced amount of fresh water are supplied, so that the energy required for heating the fresh water in at least one of the partial program steps "pre-wash", "cleaning" is reduced and the disadvantage of increased energy demand in the partial program step "rinse" is compensated.

According to a further preferred refinement, a second sensor device is provided which determines the turbidity of the wash liquor, it being possible to use the degree of turbidity as a further parameter for adjusting the pressure in the dishwashing devices. As a result, the adjustment of the pressure can be effected as a function of the degree of soiling of the dishes to be washed.

According to a further embodiment, it is provided that the pressure in the devices for flushing is low when the wash liquor is mixed with no additive and the turbidity determined by the second sensor device does not exceed a certain threshold value. The lowering of the pressure is preferably carried out in at least one of the partial program steps "prewash" or "cleaning", wherein the setting or lowering of the pressure in the other part program steps in which the dishes are acted upon with wash liquor, may be provided. By lowering the pressure in dependence on the parameters of the presence of the aggregate and the degree of contamination of the dishes, an energy-optimized operation of the dishwasher can be achieved. In addition, if the above criteria are met, lowering of the pressure can result in reduced noise emission operation.

According to a further embodiment, the devices for washing dishes have a first dish rack, a first crockery basket associated with the sprayer and a first sprayer with a circulation pump connecting the first supply line and at least a second crockery basket, the at least one second crockery basket associated second spray device and a at least a second spray device with a circulation pump connecting second supply line, wherein the pressure is selectively low in the first or the at least one second supply line or in both supply lines adjustable.

The setting of the pressure in the devices for washing dishes can on the one hand by the variation of the pump speed of a motor of a Circulation pump or by a flow cross section in the supply lines influencing reversing device are made.

In the method according to the invention for operating a dishwasher in which dishes are treated with dishwashing liquor in a dishwashing program step, the pressure in the devices for washing dishes is set as a function of the metered addition of an additive, in particular a rinse aid.

Preferably, the setting of the pressure in the dishwashing devices is additionally made dependent on a measured turbidity of the wash liquor, whereby full pump pressure is built up in the dishwashing devices when a high amount of debris has been detected by the turbidity sensor.

Accordingly, the pressure in the apparatus for washing dishes is set low when no additive is added to the wash liquor and the turbidity does not exceed a certain threshold.

For further optimization it can be provided that the pressure is set low in either one of the two devices for washing dishes in an upper basket or in a lower basket.

The adjustment of the pressure of the dishwashing liquor which acts upon the dishes as a function of, in particular, the absence of, the addition of an additive, in particular a rinse aid, enables on the one hand energy-optimized operation and, on the other hand, a reduced noise during operation of the dishwasher.

The invention will be described in more detail below with reference to an embodiment in the figures. Show it:

Fig. 1 a household dishwasher in a schematic representation, and

Fig. 2 a procedure for operating a household dishwasher.

In the Fig. 1 shown domestic dishwasher 1 has a washing up, in which not shown, to be cleaned Good, z. B. soiled dishes and cutlery, usually in baskets 3, 4 of a washing container 2 is filled. In the dishwasher 1, two sprayers 5, 6 are arranged, which in the dishwashing baskets 3, 4th arrange liquid to be arranged on dishes to be cleaned. This liquid, which is usually called rinsing liquor, is conveyed by means of a circulating pump 7 in supply lines 8, 9 to the spraying devices 5, 6. Usually, the liquid conveyed in dishwashers 1 is heated at least in a partial program step of a washing program, for which purpose the dishwasher 1 has a water heater 10 in the embodiment shown. The rinsing liquor conveyed in the dishwasher 1 is guided by the circulating pump 7 to an inlet connection 11 of the through-flow heater 10 and through it. The water heater has two outlet ports 12, 13. From the outlet ports 12, 13 of the water heater 10, the rinsing liquor via the supply lines 8, 9 the respective different spray means 5, 6 fed. The necessary for heating the liquid in the water heater 10 heating elements are not shown in the figure.

Furthermore, a turbidity sensor 15 is associated with a line connecting the circulating pump to the instantaneous water heater 10. The turbidity sensor 15 detects the degree of turbidity of the rinsing liquor pumped by the circulating pump 7 through the line.

Schematically illustrated is also an adding device 14 for a rinse aid. The adding device 14 is associated with a sensor device 16, which is designed to detect whether or not rinse aid is in the adding device 14.

In an alternative embodiment, it may be provided that the adding device 14 is provided with a selection device with which the user of the dishwasher 1 can determine whether and, if appropriate, which amount of rinse aid is added to the rinsing liquor during a rinsing program.

Based on Fig. 2 Next, the operation method of operating the dishwasher 1 will be described below Fig. 1 described. After the start of a washing program by a user (step 100), it is checked in step 102 whether a rinse aid is to be added in the further course of the washing program. If this is the case, then a standard rinse program 104 is run through. If no rinse aid to be added, which can be determined either by the detection of the absence of rinse aid in the adding device or by an appropriate choice of the user, so will For 3-in-1 combination preparations suitable washing program started, which is adapted to the specific characteristics of these combination preparations. In such a known washing program, it is particularly attempted to delay rinse aid substance, which is usually already released during a "cleaning" part program step, up to a "rinse-through" part program step. Since the adaptation of corresponding flushing programs from the prior art is sufficiently described, a more detailed description is omitted here.

The operating method according to the invention takes during a further part program step, z. As rinsing or cleaning, a measurement of the degree of turbidity promoted by the circulating pump rinse. If the turbidity does not exceed a predetermined threshold (step 106), during at least one partial program step, the pressure applied to the dishes to be cleaned is reduced. This modified 3-in-1 wash program is in Fig. 2 in step 110 is referred to as a 3-in-1 mode / noise mode because there is reduced noise emission along with a decrease in pressure. It is thus in cases where only a small amount of dirt in the dishwasher was introduced and the full pump pressure is not required, the pump pressure is reduced. This further ensures a reliable cleaning of the dishes, on the one hand, the noise is reduced and on the other hand, a smaller amount of fresh water needs to be supplied, for. B. in a sub-program step "cleaning". In this way, in a conventional 3-in-1 wash program, as it is performed in step 108, when the haze has exceeded a certain threshold, increased energy consumption can be compensated. This results from the fact that in a partial program step "drying" a temperature higher than a conventional rinse program according to step 104 must be provided for drying the dishes of the final rinse liquid, which is set by setting the temperature of the final rinse liquid in the partial program step "rinsing". The energy reduction in a modified 3-in-1 mode compared to a conventional 3-in-1 flushing program results from the fact that a smaller amount of fresh water needs to be supplied due to the lower pressure, at least in the "cleaning" part program step. whereby the heating is connected to the required rinsing temperatures with a lower energy consumption.

The regulation of the pressure as a function of the parameters "presence of rinse aid" and "turbidity of the rinsing liquor" can be achieved by controlling the rotational speed of a motor of the circulation pump and / or by changing the flow cross section in the supply lines. For this purpose, for example, one, the output nozzle 12, 13 associated, reversing device 17 may be used, as these in the DE 101 63 184 A1 is described.

The invention provides a dishwashing machine with which an energy saving and noise reduction in a washing program adapted for combination preparations is possible in a simple and cost-effective manner by using the sensor devices already present in conventional dishwashers.

LIST OF REFERENCE NUMBERS

1 dishwasher

2 rinse tanks

3 crockery basket

4 crockery basket

5 spraying device

6 spraying device

7 circulation pump

8 supply line

9 supply line

10 instantaneous water heaters

11 inlet nozzle

12 outlet ports

13 outlet nozzle

14 adding device

15 turbidity sensor

16 sensor device

17 reversing device

100 process step

102 process step

104 process step

106 process step

108 process step

110 process step

Claims (12)

1. Dishwasher (1), especially a household dishwasher, with a washing container (2) and facilities (3, 5, 8; 4, 6, 9) for washing dishes by means of washing liquor, wherein the pressure is adjustable in the facilities (3, 5, 8; 4, 6, 9) for washing dishes, characterised in that a dispenser (14) is provided for an additive and the pressure in the facilities (3, 5, 8; 4, 6, 9) for washing dishes is able to be adjusted as a function of the dose of additive supplied in the dispenser (14).
2. Dishwasher according to claim 1, characterised in that said dishwasher has a first sensor device (16) for checking whether the dispenser (14) is provided with the additive.
3. Dishwasher according to claim 1 or 2, characterised in that said dishwasher has a selection device which enables a value to be set for whether and/or with what intensity the additive is to be dispensed.
4. Dishwasher according to one of the preceding claims, characterised in that the additive is a rinse agent and the dispenser (14) is a dosing facility for the rinse agent.
5. Dishwasher according to one of the preceding claims, characterised in that a second sensor device (15) determining a turbidity level of the washing liquor is provided, wherein the turbidity level is able to be included as a further parameter for setting the pressure in the facilities (3, 5, 8; 4, 6, 9) for washing dishes.
6. Dishwasher according to one of the preceding claims, characterised in that the pressure in the facilities (3, 5, 8; 4, 6, 9) for washing is low if the washing liquor is not mixed with any additive and the turbidity level determined by the second sensor device (15) does not exceed a specific threshold value.
7. Dishwasher according to one of the preceding claims, characterised in that the facilities (3, 5, 8; 4, 6, 9) for washing dishes comprise a first crockery basket (3), a first spray facility (5) assigned to the first crockery basket and also a first feed line (8) connecting the first spray facility with a recirculation pump (7) and at least one second crockery basket (4), a second spray facility (6) assigned to the at least second crockery basket and also a second feed line (9) connecting the at least second spray facility to a recirculation pump (7), wherein the pressure is optionally able to be set low in the first or the at least one second feed line (8, 9) or in both feed lines (8, 9).
8. Dishwasher according to one of the preceding claims, characterised in that the pressure in the facilities (3, 5, 8; 4, 6, 9) for washing dishes is able to be set by variation of the pump speed of a motor of a recirculation pump (7) or by a control switch device (17) influencing the flow cross section in the feed lines.
9. Method for operating a dishwasher, in which, in a wash program step in which washing liquor is applied to dishes, the pressure in the facilities (3, 5, 8; 4, 6, 9) for washing dishes is set as a function of the dispensing of an additive, especially of a rinse agent.
10. Method according to claim 9, characterised in that the setting of the pressure in the facilities (3, 5, 8; 4, 6, 9) for washing dishes is also made dependent on a measured turbidity level of the washing liquor.
11. Method according to claim 9 or 10, characterised in that the pressure in the facilities for washing dishes is set to low if no additive is added to the washing liquor and the turbidity level does not exceed a specific threshold value
12. Method according to one of claims 9 to 11, characterised in that the pressure is optionally set to low in one of the two facilities (3, 5, 8; 4, 6, 9) for washing dishes in an upper basket or in a lower basket.

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