CN200987659Y - Dish-washing machine - Google Patents

Abstract

The utility model relates to a dishwasher, which has a washing tank and a device for washing articles with washing liquid and an adsorption drying device, wherein the adsorption drying device has a device for transmitting air with the washing tank A connected adsorption column comprising a reversibly dehydrogenable material, wherein the adsorption column is used on the one hand to dry the tableware and on the other hand to use the thermal energy used for desorption of the adsorption column to heat the washing liquid in the washing tank and/or laundry items. In order to obtain a structure of very simple design, the adsorption drying device is provided with a fan, and the dishwasher is provided with a main control unit, through which the rotational speed of the fan is controlled. The moisture absorption capacity of the dishwasher is thus significantly increased, while the duration of the "drying" subprogram step is reduced.

Description

dishwasher

technical field

The utility model relates to a dishwasher with an adsorption drying device. The invention also relates to a method for operating a dishwasher with at least one "drying" subprogram step in which a fan blows air from the dishwasher's sink And/or directing ambient air into the wash tank through an adsorption column with reversibly dehydrogenating material and dehumidifying the air during this transfer.

Background technique

Dishwashers generally have a well-known washing method whose program sequence usually consists of the following subprogram steps: at least one "prewash" subprogram step, one "washing" subprogram step, at least one "intermediate washing" subprogram step , a "rinse" subprogram step and a "dry" subprogram step. To increase the washing effect, the washing liquid is therefore heated before or during a certain subprogramme step. The washing liquid is usually heated by means of electric heaters. For drying laundry items in dishwashers, different drying systems are known.

DE 2016831 therefore discloses a dishwasher of the type mentioned at the outset, in which the air of the washing tank is introduced into the reversibly dehydrogenable material via a closable opening in the wall of the washing tank and thus passes through a The opening reaches the outside. The desorption of the reversibly dehydrogenated material takes place during the standstill phase of the dishwasher, the water vapor thus produced being conducted to the outside through the opening. The above-mentioned dishwashers are disadvantageous with regard to energy consumption, since the regenerating of the reversibly dehydrogenable material takes place during a shutdown of the dishwasher, so that no subroutine steps described are started to be carried out during this time. A further disadvantage is that the removal of the water vapor generated during the regeneration of the reversibly dehydrogenated material to the outside does not preclude damage to surrounding kitchen appliances. In this case, the regeneration is associated with an additional energy requirement which additionally results in the energy requirement required during the subprogram steps.

In order to keep the energy consumption as low as possible during the operation of the dishwasher, DE 10353774.0 of the applicant discloses a dishwasher with a sink and a device for rinsing dishes with washing liquid, which has a A sorption column comprising a reversibly dehydrogenatable material connected to an air-introduced washing tank, wherein the sorption column is used at least partially to dry dishes on the one hand and at least partially utilizes the thermal energy used for desorbing the sorption column on the other hand, to warm the washing liquid and/or dishes present in the sink.

In order to solve a similar problem, the applicant's DE 10353775.9 proposes that, in order to operate the dishwasher, in at least one "drying" subprogram step, the air in the washing tank and/or the air in the surrounding environment is passed through the adsorption column and introduced into the In the washing tank, where the adsorption column comprises a reversibly dehydrogenating material, and the air has no influence on the humidity during the introduction.

By using reversibly dehydrogenatable materials with hygroscopic properties, such as zeolites, it is generally no longer necessary to heat the item to be handled in a subprogram step preceding the “drying” subprogram step. Considerable energy can thus be saved.

EP0358279B1 discloses a device for drying tableware in a domestic dishwasher, wherein the washing liquid is heated by a heater, preferably an electric continuous heater, arranged outside the sink, wherein a largely closed A drying system in which the air in the washing tank passes through a drying device that can be regenerated by heating, and is circulated back to the washing tank by the drying device. The drying device thus consists of a drying container in thermal contact with the heater, which is filled with a hygroscopic desiccant. By connecting the drying container to the heater already present for heating the washing liquid, the drying device is ready for operation immediately after the end of the washing process. The desiccant here acts at least partially as a jacket for the heating element of the heater, so that the desiccant in the drying container is heated and thus dried during each heating operation.

The drying container is formed as a double-walled hollow cylinder in which the drying material is placed. In order to connect the closed air system, the inlet and outlet are arranged diagonally opposite. This has the disadvantage that a relatively high air flow resistance occurs, so that the fans provided for conveying the air flow have to be operated at a higher power. It has been found that this has negative effects with regard to noise formation and energy consumption.

Due to the inhomogeneous heating of the desiccant due to the design of the sorption drying device, the desorption is time-consuming and also leads to local overheating of the desiccant, which leads to irreversible losses. Therefore, desorption is also difficult, because the heater is arranged in the center of the double-walled hollow cylinder, and since the air flow flows sideways from the axial direction, the heat is transferred radially to the desiccant placed near the outer wall of the hollow cylinder. is impossible.

Utility model content

The object of the present invention is to provide a method for operating a dishwasher and a dishwasher with which the duration of a washing program with a plurality of subprogram steps can be shortened.

This object is solved by such a dishwasher. In such a dishwasher according to the invention, in particular a domestic dishwasher, the dishwasher has a washing tank and a device for washing the items to be washed by means of washing liquid, as well as an adsorption drying device, The adsorption drying device has an adsorption column in air communication with the washing tank, which contains reversibly dehydrogenated material, wherein the adsorption column is used on the one hand to dry tableware, and on the other hand to use the adsorption column used for desorption. Thermal energy for heating the washing liquid and/or washing items present in the washing tank. According to the utility model, the adsorption drying device is provided with a fan, and the dishwasher is provided with a main control unit, and the rotation speed of the fan is controlled by the main control unit. Such a dishwasher has a simple construction and has increased moisture absorption properties and shortens the duration of the "drying" subroutine.

An advantage is that a very simple design results for such a dishwasher. The dishwasher can be constructed on the basis of the principles described in DE 10353774.0 of the applicant, the contents of which are incorporated in the present application as far as appropriate. The machines described here differ in the control and operation of the sorption drying device, in particular the fan, which, thanks to its adjustable speed, allows controlled drying.

According to a preferred feature, during the subprogramme step using the washing liquid to be heated, air from the washing tank and/or ambient air passes through the adsorption column and enters the washing tank, preferably in a "drying" subprogramme step.

According to another preferred feature, the washing tank has an outlet with a conduit leading to the adsorption column, wherein the conduit preferably has a non-return valve, and in the direction of flow thereafter preferably has a conduit leading to the ambient air. and the washing tank has an inlet with a duct from the drying column, wherein said fan is arranged in the duct leading to the adsorption column, at least briefly, at least part of the air in the washing tank or Ambient air is introduced into the adsorption column. In a preferably closed air system, the exchange of dirty air from the surrounding environment is completely excluded, thereby preventing the treated laundry items from becoming soiled again. The fan can be easily controlled so that the use of the sorption column and thus the drying process can be precisely controlled.

It is expedient to provide a preferably electric heating element for desorbing the reversibly dehydrogenated material and for heating the air conveyed in the washing space. The electric heating element is preferably arranged in a reversibly dehydrogenating material or in a channel leading to the sorption column.

It is more expedient if the fan of the sorption drying device is stepless or selectable in several stages via a control element of the dishwasher.

Description of drawings

The invention is described in more detail below with the aid of an exemplary embodiment of the method in a dishwasher shown in the drawings.

The accompanying drawings show

Fig. 1 is a curve diagram of the temperature of the washing liquid in the dishwasher as a function of time.

Detailed ways

Method according to the invention for operating a dishwasher with at least one subprogram step using washing liquid to be heated to a set temperature and/or with at least one "drying" subprogram step Implemented in the described exemplary embodiment of the dishwasher, the construction shown is as described in DE 10353774 and/or DE 10353775 of the applicant. A dishwasher has known washing methods, the program of which usually consists of at least one "prewash" subprogram step V, a "washing" subprogram step R, at least one "intermediate washing" subprogram step Z, a "rinse" Consists of subroutine step K and a "drying" subroutine step T. The drying in the examples is preferably carried out as described in DE 10353774 and/or DE 10353775, the content of which is incorporated into the present application. A typical temperature profile of the washing liquid during the subprogram steps is shown here in the drawing, wherein the drawing not only describes the operation in a conventional dishwasher, but also describes a variant of the method according to the invention run.

For the method according to the invention, the "pre-wash" subprogram step V and the "intermediate wash" subprogram step Z are of insignificant significance and are therefore hardly considered in the following description. At the beginning of the "washing" subroutine step R, the washing liquid is generally heated to a nominal temperature _Tnominal in order to obtain the desired washing effect. As is well known in the prior art, in an energy-optimized dishwasher with an adsorption drying device, the desorption also takes place during the "washing" subprogram step R, ie heating the reversibly dehydrogenated materials. The relevant content of DE10353774 and/or DE10353775 is incorporated into the present application.

For heating the washing liquid, a conventional heater, for example a continuous heater, can be used. It is conceivable to dispense with this "water heater" and use only the energy necessary for desorption.

For this purpose, a (air) heater arranged in the sorption drying device is also operated, which heats the reversibly dehydrogenated material, for example zeolite, to a higher temperature. During desorption of reversibly dehydrogenable materials, air from a wash tank, for example with an outlet, is directed through an adsorption column and then through an inlet back into the wash tank, where the air passes the heater during transport is heated. Thus, air is sucked out of the washing tank by means of a fan and pressed through the sorption columns. The hot water vapor coming out of the adsorption column and the now heated air enter the washing tank through the above-mentioned inlet and meet there with the circulating treatment liquid, that is, the washing liquid and/or the tableware, the washing liquid and / or the tableware is thus heated.

Usually the sorption drying device is only operated until this point: until the reversibly dehydrogenated material is completely desorbed, ie dried (section A in the drawing). In the exemplary embodiment shown in the drawing, it is possible to achieve a state at _time t a in which the washing liquid and/or the objects to be treated reach a temperature T _Des . Usually this temperature is lower than _the rated temperature Tnom to be obtained. In order to eliminate this temperature difference, the electric heating element and fan of the adsorption drying device are continuously operated and the hot air is forced into the washing tank until the circulating washing liquid and/or the items to be treated reach the desired rated temperature (B part). This state is reached at time t _b if the sorption drying device, in particular the power of the heater, the rotational speed of the fan, and the arrangement and geometry of the sorption column are designed accordingly.

In order to be able to carry out the "washing" subprogram step R more quickly, that is to say to be able to reach the desired setpoint temperature _Tsetpoint more quickly, according to another variant, an additional heater can be provided, which during the section A And/or during the section for raising the temperature from T _Des to _Tnom , the washer liquid is driven such that at one point in time t _c has reached the setpoint temperature _Tnomin (section C). The additional heater can optionally be a water heater, for example a continuous heater, or also an air heater integrated into the air circulation device. In both cases, the additional heater is dimensioned such that only a small heating power is available, in which case the heater will be between T _Des and T _Rated The unreached temperature difference is eliminated. Although not evident in the figures, the person skilled in the art will have no problem appreciating the fact that the end of the washing liquid is independent of the instant at which the target temperature Tnom is _reached ( _tb or _tc in the examples). Heating state, and subsequently causing the treatment temperature to drop to the end of step R of the "washing" subroutine. How sharp the drop in process temperature is and how long it lasts depends on the type of washing program carried out and the insulation properties of the dishwasher (Dmmmeigenschaften).

According to another variant, it can also be provided that the rotational speed of the fan of the sorption drying device is increased during the “washing” subprogram step R in order to achieve a further reduction in the time to reach the setpoint temperature _Tsetpoint . This can be preselected for the operator of the dishwasher, for example via an operating element.

In conventional dishwashers, the drying of the wash items is carried out by so-called autothermal drying in the "rinse" and "dry" subprogram steps (section 1). The washing liquid is then heated in the "rinse" subprogram step, so that the hotly rinsed washing items dry themselves due to the self-heating of the washing items during the drying process. In order to achieve said autothermal drying, the wash liquor is therefore heated to a temperature T _K in the "rinse" subprogram step and applied to the wash items by means of spraying devices. The relatively high temperature of the wash liquor in the "rinse" subroutine step, typically 65°C to 75°C, achieves a transfer of sufficient heat to the wash items so that water adhering to the wash items passes through the The heat in the laundry items is evaporated.

A substantial energy saving is achieved with the sorption drying device, since in this device in principle no heating of the washing liquid (section 2) is required in the "rinsing" subprogram step K (section 2), but all this can be done to a lesser extent. Heat as described (section 3). The drying is carried out in such a way that in the "drying" subroutine step the air from the washing tank and/or from the ambient air is led through the adsorption column into the washing tank, wherein the reversibly dehydrogenated The adsorption column of the material draws moisture from the air when it is turned on. By using hygroscopic, reversibly dehydrogenatable materials, such as zeolites, it is generally not necessary to heat the item to be treated in the subprogram step preceding the "drying" subprogram step (section 2), but in addition it is possible after the "rinse" to a lower temperature, for example to 30° C., (section 3). The heating of the air by means of the sorption column, in which the heat of condensation of the water vapor is free, increases its hygroscopic capacity each time it passes through the sorption column, which leads to optimized drying results and shortened drying times. It is generally not necessary to additionally heat the air with an additional heater in the "drying" subprogram step beyond the heating with the sorption column, and thus, for example, to heat the dishes in a dishwasher, because in The heat that becomes free in the adsorption column is sufficient to heat the air to a higher temperature, for example 70°C. By means of the heat of condensation, the sorption column itself is heated to a temperature of, for example, 160° C.

Acceleration of the drying program, which is achieved in conventional dishwashers by means of a time program control and lasts up to time t ₁ , can be achieved by providing a stepless or multi-stage rotational speed control in the sorption drying device. fan to achieve. By increasing the rotational speed, the desorption process is accelerated, which leads to shorter drying times.

If during the "rinse" subprogram step the temperature increase was abandoned, the drying is ended at time t2 (section ₂ ). The previously performed heating to the rinsing temperature results in a further shortening of the drying time (section 3 ), so that the drying can be ended at time _t3 . In this case it is assumed that the drying effect or degree of drying of the laundry items to be dried is the same in all three variants.

Since the increase in the rotational speed of the fan of the sorption drying device occurs simultaneously with the increase in the radiated noise, this has the advantage that the user of the dishwasher is allowed to carry out this operating mode autonomously. This can take place, for example, by providing a corresponding operating element, which can be combined with the main control unit of the dishwasher and enables a corresponding mode of operation.

The invention provides a method with which a dishwasher of the type mentioned at the outset can be operated economically and the energy consumption associated therewith can be kept low in a time-optimized manner.

Claims (6)

1, dish-washing machine, it has a sink and one and is used for coming the device that washing articles is washed and having an adsorption dry device by cleaning solution, wherein this adsorption dry device has one and links to each other with sink transmission air ground, but the adsorption column that comprises the material of reversibly dehydrogenation, wherein this adsorption column is used for dry tableware on the one hand, be used for the employed heat energy of desorb adsorption column on the other hand, be used for heating the cleaning solution and/or the washing articles that are in sink, it is characterized in that, this adsorption dry device is provided with a fan, and this dish-washing machine is provided with a main control unit, and this fan carries out rotating speed control by this main control unit.

2, dish-washing machine according to claim 1, it is characterized in that, sink has one and has an outlet of leading to the conduit of adsorption column, wherein this conduit preferably has a shut off valve and then preferably has an inlet valve that leads to ambient air along the liquid flow path direction, and sink has an inlet that has from the conduit of adsorption column, wherein fan is arranged in the conduit that leads to adsorption column, can imports adsorption column in short-term with at least a portion of the air in the sink or with the air in the ambient air by this fan.

3, dish-washing machine according to claim 1 is characterized in that, arranges a heating element heater that is preferably electricity, but carries out desorb for the material of reversibly dehydrogenation, and heat for the air that imports in this scrubbing space.

4, dish-washing machine according to claim 3 is characterized in that, but this heating element heater is set in the material of described reversibly dehydrogenation or is arranged in the conduit of adsorption column.

5, dish-washing machine according to claim 4 is characterized in that, the rotating speed of this fan is stepless or can selects on a plurality of grades by a control element of dish-washing machine.

6, dish-washing machine according to claim 1 is characterized in that, this dish-washing machine is provided with a storage heater, for example hidden memory, is used for carrying out the employed heat energy of desorb and was stored in described storage heater before being used for heated scrub and/or washing articles.

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