EP3037027A1 - Dishwasher with a water treatment system - Google Patents

Abstract

A dishwasher has a connection (10) for raw water and a water treatment plant (100). The water treatment plant (100) comprises a softener (110), a reverse osmosis system (120) and a surge tank (130). The softener (110) is designed to soften the raw water from the port (10). The surge tank (130) is fluidly disposed between the softener (110) and the reverse osmosis plant (120) and provides a buffer for the softened water from the softener (110).

Description

The present invention relates to a dishwasher and more particularly to a dishwasher with a water treatment plant having a surge tank for safe operation of a reverse osmosis system.

background

For water treatment in dishwashers often softening plants are used, which carry out an ion exchange of the hardening ions in the raw water. For example, Ca and Mg ions are removed from the water as it passes through the ion exchanger and replaced by Na ions. Thereafter, the softened water is used after heating by a boiler to flush dishes or glasses.

In other water treatment plants, a reverse osmosis system is used to treat the raw water. The reverse osmosis system is based on a reversal of the osmotic principle and has a membrane which, in the presence of a sufficient pressure (higher than the osmotic pressure) separates the raw water into a retentate (concentrate) and a permeate. The retentate does not pass through the membrane and is then fed to the waste water of the dishwasher. The permeate passes through the membrane and is then heated in the boiler of the dishwasher and used for rinsing (for example, dishes).

Both possibilities of water treatment are limited controllable. In addition, a combination of both water treatment options is not easily possible because the existing flow rates are very different.

From the DE 103 52 120 A1 For example, a dishwasher with a connection for raw water and a water treatment plant is known.

Therefore, there is a need for a dishwasher that combines the advantages of ordinary water softening systems (for example, a high ratio of permeate to raw water) with the very good quality achievable by reverse osmosis systems.

Summary of the invention

The above object is achieved by a dishwasher according to claim 1.

The present invention relates to a dishwasher with a connection for raw water and a water treatment plant. The water treatment plant includes a softener, a reverse osmosis system and an expansion tank. The softener is designed to soften the raw water from the outlet. The surge tank is fluidly disposed between the softener and the reverse osmosis unit and provides a buffer for the softened water from the softener.

In the context of the present invention, softeners are all agents which are suitable for extracting from a raw water the hardening constituents (for example calcium ions and magnesium ions) and replacing them with less hardening materials. As raw water that water is referred to, which can be removed, for example, from a standard water connection of a public water supply.

Optionally, in further exemplary embodiments, the expansion tank has an outlet for a bypass connection for bypassing the reverse osmosis system, wherein the outlet is arranged on the expansion tank such that air or optionally water can be output from the water treatment plant.

In further embodiments, the dishwasher has a boiler. The boiler has a first inlet connected to the bypass connection of the surge tank and a second inlet to receive permeate from the reverse osmosis plant.

The bypass connection is, for example, attached to an outlet of the surge tank in such a manner that excess water is automatically discharged via the bypass pipe when a predetermined level (height) within the surge tank is exceeded. Thus, it is possible that, when other outlets of the surge tank are closed, excess water can automatically be routed around the reverse osmosis plant and, for example, directed directly into the boiler.

Furthermore, the bypass connection has the advantage that venting can be achieved by, for example, because the predetermined level is above an average water level, which is reached under normal operating conditions, and there is room for escaping air. In addition, the water remains in the surge tank for a certain period of time, so that during this certain period of time small gas bubbles that might be present in the water can escape and be discharged via the bypass connection.

Therefore, in other embodiments, the surge tank optionally has a level sensor for measuring a water level in the surge tank and / or a port for draining and supplying maintenance agents.

The level sensor of the expansion tank, for example, can also be used to avoid accidental overflow of the surge tank and thus passing the water past the reverse osmosis plant. This can ensure that only water reaches the boiler, which has also passed the reverse osmosis system. The level sensor may in turn be connected to a control unit which provides central control for all components.

The reverse osmosis system is designed to separate water into a permeate used for rinsing and a retentate to be disposed of. Optionally, in further exemplary embodiments, the dishwasher has a conductivity measuring device for measuring a quality of the permeate and a reflux line for returning the permeate to the expansion tank. The conductivity measuring device is arranged, for example, such that a conductivity measurement for determining the quality can be carried out before the permeate flows back into the expansion tank via the return flow line.

The conductivity measuring device can, for example, trigger or control the return flow of the permeate to the expansion tank by providing a corresponding measuring signal which, for example, causes a control unit to open a corresponding valve along the return flow line, so that at least part of the permeate from the reverse osmosis system returns reaches the expansion tank. Thus, it becomes possible to control the quality of the permeate continuously by controlling the amount of reflux and reflux time.

Optionally, in other embodiments, the dishwasher includes a regenerant container connected to the softener and providing a reservoir for a regenerant. The regenerant container optionally has a filling sensor for measuring a filling level of the regenerating agent

Ion exchanger (softener) should be topped up regularly to achieve optimal softening. To make this process as automatic as possible, the Regeneriermittelbehälter provides a memory for the regenerating agent, which is supplied to the softener as needed, so that the softener can always be operated with an optimal filling with regenerating agent. In particular, the regenerant container prevents the softener from running empty. An optional warning signal can be output via the optional level sensor if the volume of the regenerant tank drops below a predetermined level so that a timely replenishment is possible.

Optionally, in further embodiments, the dishwasher to a water technical safety device, which is arranged fluidly between the connection for raw water and the softener. The water safety device provides an air gap and a connection for a water connection (for peeling water), so that the raw water overcomes the air gap before being fed to the softener. The water connection is connected to the expansion tank, bypassing the softener.

In the present specification, the term "peeling water" is used for any water which is present in the water technical safety device and is not directed from the water technical safety device to the water softener. For example, overcoming the air gap causes the pressurized water to finely disperse and thus to form a water vapor or small drops of water (especially at higher pressure) that can be dissipated via the peeling water connection. In addition, the water connection ensures that the air gap can not "run" and any water that can not get to the softener (for example due to a backwater) is drained via the water connection.

Optionally, in further embodiments, the dishwasher further comprises a pump between the surge tank and the reverse osmosis system. The pump is configured to supply softened water at a predetermined pressure to the reverse osmosis system. This pressure can be chosen such that the osmotic pressure (the Among other things depends on the membrane) will overcome and the reverse osmosis principle is set in motion. Therefore, for example, the pump is configured to generate a pressure sufficient to operate the reverse osmosis system.

Optionally, in further embodiments, the dishwasher further includes a softener waste water line connected to a sewer line of the machine.

In further exemplary embodiments, the dishwasher has a control unit, wherein the control unit is designed to detect and control operating states of the water treatment system. For this purpose, the dishwasher may further comprise: a first valve device and / or a second valve device and / or a third valve device and / or a fourth valve device. The control unit is designed, for example, to control the first valve device and / or the second valve device and / or the third valve device and / or the fourth valve device and / or the pump and to detect results of the conductivity measuring device.

The first valve device serves to control a backflow along the return flow line for returning the permeate into the expansion tank. The second valve device is formed on the raw water connection in order to provide a predefined volume flow of raw water of the water treatment plant. The third valve device is arranged between the regenerant container and the softener and designed to supply controlled regeneration agent to the softener. The fourth valve device is positioned after the softener. The fourth valve means serves either to rinse out the brine after regeneration and to guide it in the direction of wastewater or else to direct the treated and softened water in the direction of the expansion tank. At least one of the first to fourth valve means may be formed as a solenoid valve or as a differently controllable valve.

The predefined volume controlled by the second valve device may, for example, be adapted to a typical throughput of the ion exchange and / or the reverse osmosis system, depending on which of the two components has a lower throughput or depending on which water consumption for the dishwasher is to be expected. This ensures that an unwanted overflow is avoided in the expansion tank and the ion exchanger can be operated constantly. Thus, a synchronization of the water volume can be made through the expansion tank.

According to further embodiments, the control unit is optionally designed to perform at least one of the following functions.

A first function is to detect a water level of the surge tank and, based thereon, to control the pump and / or the second valve device upstream of the water management device to maintain a level in the surge tank constant.

A second function is to detect a result of a conductivity measurement of the conductivity measuring device and, based thereon, to effect a permeate reflux by the first valve device between the reverse osmosis system and the expansion tank to such an extent or until the permeate reaches a predetermined target value for the conductivity.

A third function is to control the third valve device such that softening of the softener reaches a predetermined value.

A fourth function is to selectively supply the boiler with softened water via the bypass which bypasses the reverse osmosis system and serves as an overflow and / or vent. In this case, close the permeate outlet so that softened water can reach the boiler via the bypass line.

Brief description of the figures

Fig. 1

eine Spülmaschine nach einem Ausführungsbeispiel der vorliegenden Erfindung zeigt;

Fig. 2

eine weitere Spülmaschine gemäß einem weiteren Ausführungsbeispiel der vorliegenden Erfindung zeigt;

Fig. 3

weitere optionale Komponenten der Spülmaschine aus der Fig. 2 zeigt; und

Fig. 4A bis 4E

einen Ausgleichsbehälter, wie er in Ausführungsbeispielen der vorliegenden Erfindung zum Einsatz kommt, zeigt.

The invention will be described in more detail below with reference to the accompanying drawings, in which:

Fig. 1

a dishwasher according to an embodiment of the present invention;

Fig. 2

another dishwasher according to another embodiment of the present invention;

Fig. 3

other optional components of the dishwasher from the Fig. 2 shows; and

Fig. 4A to 4E

a surge tank, as used in embodiments of the present invention, shows.

Detailed description

Fig. 1 1 shows parts of a dishwasher having a connection 10 for raw water and a water treatment plant 100. The water treatment plant 100 comprises a softener 110, a reverse osmosis system 120 and a compensation tank 130. The softener 110 is designed to soften the raw water from the connection 10. The surge tank 130 is fluidly disposed between the softener 110 and the reverse osmosis plant 120 and provides a buffer for the softened water from the softener 110.

Fig. 2 shows a further embodiment with further optional components for the dishwasher.

The dishwasher as in the Fig. 2 again shows a softener 110 having an inlet 110a and an outlet 110b. The inlet 110a is connected to an outlet 150b of a water technical safety device 150. An inlet of the water technical safety device 150a is connected to the raw water connection 10 via a second valve device 162. The second valve device 162 is designed to control the raw water inflow from the raw water connection 10.

The dishwasher further includes the surge tank 130 having a first inlet 131a, a second inlet 131b, a third inlet 131c, a first outlet 132a, a second outlet 132b, and a port 130e. The first inlet 131a is connected to the outlet 110b of the water softener 110. The second inlet 131b is connected to the water technical safety device 150 via a water connection (peeling water connection) 155. The water technical safety device 150 also has an outlet which is connected to the peeling water connection 155. The third inlet 131 c of the surge tank 130 is connected to a first valve device 161. The first outlet 132a is connected to a bypass line 136 and the second outlet 132b is connected to a pump 170.

The exemplary dishwasher further includes a boiler 300, a reverse osmosis system 120, a conductivity meter 140, and the pump 170. The boiler 300 is connected via a bypass line 136 to the first outlet 132 a of the surge tank 130. In addition, the boiler 300 can be connected via the first valve device 161 to the third inlet 131 c of the expansion tank 130. The pump is fluidly connected between an inlet of the reverse osmosis system 120 and the second outlet 132b of the surge tank 130. The reverse osmosis system 120 has a retentate outlet 122, which is connected to a wastewater connection 20. In addition, the reverse osmosis system 120 has a permeate outlet 121, which is connectable to the boiler 300 and the first valve device 161. At the connection 305 between the permeate outlet 121 and the boiler 300, the conductivity measuring device 140 is arranged.

Thus, the raw water passes through the raw water connection 10 after passing through the second valve device 162 first in the water technical safety device 150. There, the raw water passes through an air gap and passes through the outlet 150b to the water softener 110. The generated during the overcoming of the air gap peeling water is on the Peeling water connection 155 derived in the expansion tank 130. Likewise, the water is also passed into the expansion tank 130 via the outlet 110b after passing through the softener 110. In the expansion tank 130, the water is first collected. An optional level sensor 135, which is designed, for example, to constantly monitor a level in the expansion tank 130, is arranged on the compensation tank. In addition, the surge tank has a port 130e which is connected via a further line 133 to a connection 15, which in turn is connectable or usable with the waste water connection 20 in order to provide a chemical connection (for introduction of chemicals).

From the surge tank 130, the water may pass into the reverse osmosis plant 120 via the second outlet 132b and after passing the pump 170. The pump 170 pumps the water from the expansion tank 130, for example, at a pressure such that the reverse osmosis system 120 can use the reversal of the osmotic principle to further treat the water. In this case, the water is separated by the membrane 123 into a retentate, which is fed via the Retentatauslass 122 to the wastewater 20, and into a permeate, which is supplied to the Permeatausgang 121 after passing through the membrane 123. Subsequently, the permeate reaches the boiler 300.

Optionally, on the way between the permeate outlet 121 and the boiler 300, the water may be exposed to conductivity measurement by a conductivity meter 140. Depending on the result of the conductivity measurement, the first valve device 161 can be operated, which establishes a fluid connection between the permeate outlet 121 and the third inlet 131c of the surge tank 130 so as to create a closed circuit which is useful for the quality of the water continue to increase. The conductivity measurement is only optional. In further embodiments, the feedback cycle is performed based on a parameter (eg, downtime or return time), i. H. a return is performed for a predetermined time without conducting a conductivity measurement.

Optionally, when the pump 170 is not operating, the water can not pass from the surge tank 130 to the reverse osmosis plant 120. However, since the water softener 110 is constantly supplying water, the level in the surge tank 130 rises until it reaches the level of the first outlet 132a, and then directly to the boiler 300 via the bypass line 136. Thus, it can be achieved by a controller (for example, the pump 170) that water only passes through the softener 110 in the boiler 300.

After heating the water in the boiler 300, the water may be supplied via an outlet to a washing compartment of the dishwasher (not shown in the figure). The boiler 300 has an optional vent 330.

Fig. 3 shows further optional elements of the dishwasher according to embodiments of the invention. Compared to the embodiment, which in the Fig. 2 is shown, the embodiment of the Fig. 3 additionally the flushing space 400, further pumps 520, 530, 540 and a regenerant tank 200.

For example, the regenerant container 200 has a level sensor 210 and is configured to store a regenerant whose level in the regenerant container 200 is detected via the level sensor 210. The regenerant container 200 is connected via a third valve direction 163 to an inlet 110 a of the water softener 110. In addition, the dishwasher has an aperture 280 and a feed tank 285. The orifice 280 is formed between the second valve device 162 and the water technical safety device 150 and is able to allow the inflow of water either to the water technical safety device 150 or at least to direct a subset of the raw water to the feed tank 285. The feed tank 285 is disposed between an outlet of the orifice 280 and an inlet 201 of the regenerant tank 200 so that water can be selectively directed into the regenerant tank 200 via the orifice 280 and the feed tank 285. In addition, the feed tank 285 has an optional level sensor which keeps a volume of raw water in the feed tank 285 constant (for example, the volume may be between 100 and 300 ml or about 180 ml). Excess water from the feed tank 285 is fed via a drain line 155 to the expansion tank 130.

The outlet 110b of the water softener 110 is connected to the fourth valve device 164, which establishes a flow of water either between the softener 110 and the sewer line 116, or releases it between the softener 110 and the expansion tank 130.

The operation of the water storage can be described as follows. The regenerant container 200 is filled with salt, for example, and the required water can be supplied to the regenerant container 200 via the feed container 285, which in turn is filled via the orifice 280 in the inlet to the water-technical safety device 150. The overflow of the feed tank 285 then goes, for example, in the peeling water and is supplied directly to the surge tank 130. The regenerant passes through the Besolungsventil (third valve means 163) in the ion exchanger (softener 110). For example, it can be determined via the salt level gauge 210 whether sufficient brine is present in the salt container 200. This can be detected, for example, via the physical properties of the liquid density and assigned to a position of a float. If the density should decrease due to a decreasing brine concentration, the float also drops and can thus trigger an alarm (eg via a reed contact) which will be displayed on a display of the dishwasher. Thus, a user knows whether the salt concentration is sufficient or whether additional salt should be refilled.

Thus, the raw water can be passed from the raw water connection 10 via the second valve 162 directly into the regenerant 200. Thereafter, the regeneration agent can be supplied to the softener 110 via the third valve device 163 (which is opened correspondingly in this mode) via a regeneration agent from the regenerant container 200.

The washing compartment 400 of the dishwasher from the Fig. 3 has an inlet 401 and an outlet 402. In addition, spray nozzles 410, 420 are formed in the washing compartment 400, which effects a distribution of the water in the washing compartment 400. The spray nozzles 410 serve, for example, the rinsing and the other spray nozzles 420 are used during the rinse and cleaning. At the inlet 401, a vent 450 is formed and the outlet 402 is connected to the vent 450 via a second pump 520. The vent 450 serves primarily the purpose, for example, in the case of a deeper-lying sewer line to prevent empty suction of the tank. The vent 450 is further designed to extract air bubbles from the waste water, which is pumped via the outlet from the washing chamber 400 through the second pump 520 to the vent, and to supply them to the waste water connection 20 after this venting. The air extracted by the vent is supplied to the flushing space 400 via the inlet 401.

In addition, the dishwasher has a connection of the boiler 300 with the spray nozzles 410 in the washing compartment, wherein a third pump 530 is arranged between the boiler 300 and the spray nozzles 410. The third pump 530 pumps the hot water from the Boiler 300 to the spray nozzles 410. In addition, the boiler 300, the optional vent 330 on.

In addition, a softener effluent line 116 is formed between the fourth valve device and the sewage port 20. The fourth valve device 164 is also configured to selectively connect the exit 110b of the softener 110 to either the softener effluent line 116 or to establish between the softener 110 and the surge tank 130.

The dishwasher of Fig. 3 further includes a fourth pump 540 which pumps flushing water from the washing compartment 400 to the nozzles 420 so as to provide a flushing circuit in the washing compartment 400.

The retentate exit 122 of the reverse osmosis system 120 can also be connected to the wastewater connection 20 via a retentate line 127.

All other components were already in the Fig. 2 described, so that can be dispensed with a repetition. It is understood that in the Fig. 3 shown further components are optional or need to be realized in a different combination or only some of them.

1. 1. Das Rohwasser kann über den Rohwasseranschluss 10 über die wassertechnische Sicherungseinrichtung 150 und die Enthärtung 110 zunächst in den Ausgleichsbehälter 130 gelangen. Dort wird es über die Pumpe 170 zur Umkehrosmoseanlage 120 gepumpt. Von dort wird das Permeat über den Permeatausgang 121 in den Boiler 300 geleitet. Nach Aufheizung in dem Boiler wird das Wasser über die dritte Pumpe 530 zu den Sprühdüsen 410 in den Spülraum 400 gepumpt. Ein Spülvorgang läuft beispielsweise derart ab, dass zuerst das im Spülmaschinentank befindliche Wasser über die vierte Pumpe 540 und den Wascharm 420 über eine bestimmte Zeit umgewälzt wird. Dann wird im Anschluss daran das Wasser aus dem Boiler 300 über die dritte Pumpe 530 dem Nachspülsystem 410 zugeführt. Das überschüssige Wasser nach einem Spülvorgang wird dann über die zweite Pumpe 520 dem Abwasser zugeführt.
2. 2. Die Umkehrosmoseanlage 120 wird zur weiteren Wasseraufbereitung nicht genutzt. In einer anderen Betriebsweise wird das Wasser nach dem Enthärter 110 in dem Ausgleichsbehälter 130 gesammelt. Da die Pumpe 170 in diesem Modus nicht arbeitet, steigt das Niveau in dem Ausgleichsbehälter 130 an bis es über den Überlauf 136 direkt in den Boiler 300 gelangt. Daran anschließend folgt der gleiche Wasserverlauf, wie er zuvor beschrieben wurde.
3. 3. Eine weitere Verbesserung des ersten Arbeitsmodus kann dadurch erreicht werden, dass die optionale Leitfähigkeitsmesseinrichtung 140 feststellt, dass das Permeat von der Umkehrosmoseanlage 120 nicht die erforderliche Qualität aufweist. In diesem Fall kann die erste Ventileinrichtung 161 derart aktiviert werden, dass die Rückflussleitung 145 geöffnet wird und das Wasser von dem Permeatausgang 121 zurückgeleitet wird in den Ausgleichsbehälter 110. Auf die optionale Leitfähigkeitserfassung kann verzichtet werden, wenn in der Steuerung eine bestimmte Zirkulationsdauer zur Eliminierung des Leitfähigkeitspeaks beispielsweise in Abhängigkeit einer Stillstandzeit hinterlegt ist. In diesem Fall kann auf eine Leitfähigkeitsmesseinrichtung verzichtet werden. Somit entsteht ein geschlossener Kreislauf, sodass das Wasser von dem Ausgleichsbehälter 110 wiederum über die Pumpe 170 in die Umkehrosmoseanlage 120 gelangt. Von dort gelangt es wiederum über die erste Ventileinrichtung 161 zurück in den Ausgleichsbehälter 130. Dieser geschlossene Kreislauf kann solange fortgesetzt werden, bis die Leitfähigkeitsmesseinrichtung 140 signalisiert, dass die Wasserqualität ausreicht, woraufhin die erste Ventileinrichtung 161 geschlossen werden kann und das Permeat von dem Permeatausgang 121 direkt in den Boiler 300 gepumpt wird. Bei weiteren Ausführungsbeispielen ist es ebenfalls möglich, dass nur ein Teil des Permeats über den Kreislauf zurück geleitet wird (z.B. durch ein teilweises öffnen der ersten Ventileinrichtung 161).
4. 4. Der Enthärter 110 wird regeneriert, wenn keine freien Bindestellen mehr im Harz vorhanden sind. Nach einem komplett aufgebrauchten Harz wird dazu der Enthärter mit Sole regeneriert, die über das Besolungsventil (dritte Ventileinrichtung 163) dem Enthärter 110 zugeführt wird. Um den Solebehälter 200 mit Wasser aufzufüllen, wird noch vor der wassertechnischen Sicherungseinrichtung 150 über die Blende 280 dem Zulaufwasser ein kleiner Teilstrom entzogen, der den Zulaufbehälter 285 (Behälter im Zulauf zum Solebehälter) füllt. Über diesen Behälter 285, der geodätisch über dem Salzbehälter (Regeneriermittelbehälter 200) liegt, wird der Regeneriermittelbehälter 200 mit Rohwasser befüllt.

The dishwasher may further comprise a control unit that implements one or more or all of the following modes of operation:

1. 1. The raw water can pass through the raw water connection 10 via the water technical safety device 150 and the softening 110 first in the expansion tank 130. There it is pumped via the pump 170 to the reverse osmosis system 120. From there, the permeate is passed via the permeate outlet 121 into the boiler 300. After heating in the boiler, the water is pumped via the third pump 530 to the spray nozzles 410 in the washing compartment 400. For example, a flushing operation is such that first the water in the washing machine tank is circulated through the fourth pump 540 and the washing arm 420 for a certain period of time. Then, the water is then supplied from the boiler 300 via the third pump 530 the Nachspülsystem 410. The excess Water after a flushing operation is then fed via the second pump 520 to the wastewater.
2. 2. The reverse osmosis system 120 is not used for further water treatment. In another mode of operation, the water is collected after the softener 110 in the surge tank 130. Since the pump 170 does not operate in this mode, the level in the surge tank 130 rises until it passes directly into the boiler 300 via the overflow 136. This is followed by the same course of water as previously described.
3. 3. Further improvement of the first mode of operation may be achieved by the optional conductivity meter 140 determining that the permeate from the reverse osmosis system 120 is not of the required quality. In this case, the first valve device 161 can be activated such that the reflux line 145 is opened and the water is returned from the permeate outlet 121 into the expansion tank 110. The optional conductivity detection can be dispensed with if a certain circulation time is required in the control to eliminate the Conductivity peaks, for example, depending on a downtime is deposited. In this case, can be dispensed with a conductivity measuring device. This results in a closed circuit, so that the water from the expansion tank 110 in turn passes through the pump 170 in the reverse osmosis system 120. From there it again passes via the first valve device 161 back into the expansion tank 130. This closed circuit can be continued until the conductivity measuring device 140 signals that the water quality is sufficient, whereupon the first valve device 161 can be closed and the permeate from the permeate outlet 121 is pumped directly into the boiler 300. In further embodiments, it is also possible that only a portion of the permeate is returned via the circuit (eg, by partially opening the first valve device 161).
4. 4. Softener 110 is regenerated when there are no more free binding sites in the resin. After completely depleted resin, the softener is regenerated with brine, which is supplied via the Besolungs valve (third valve device 163). the softener 110 is supplied. In order to fill the brine tank 200 with water, a small partial flow is withdrawn from the inlet water via the orifice 280 before the water technical safety device 150, which fills the inlet tank 285 (tank in the inlet to the brine tank). About this container 285, which is geodetically above the salt container (Regeneriermittelbehälter 200), the Regeneriermittelbehälter 200 is filled with raw water.

Fig. 4A FIG. 12 shows a perspective view of the regenerant container 130 with the first inlet 131a connectable to the softener 110. Further, the surge tank 130 has the second inlet 131b on an upper side, which is connectable to the water technical safety device 150. In addition, the surge tank 130 has a first outlet 132a on an upper side, which is connectable to the bypass line 136 toward the boiler. Arranged laterally is the second outlet 132 b, which is connectable to the pump 170. In addition, the connection 130e, which can be connected to the chemical connection or the wastewater connection, is arranged laterally. Finally, laterally the third inlet 131c is formed, which is connectable to the first valve device 161 and serves the above-mentioned closed circuit.

In addition, the surge tank 130 has a housing with a cavity therein to collect the water there. Finally, the surge tank 130 has a port for the level sensor 135 (shown in FIG Fig. 4a not shown), which may be at least partially realized in the surge tank 130.

Fig. 4B shows a cross-sectional view through the surge tank 130, wherein the connection for the level sensor 135 is visible. For example, the level sensor 135 may couple to a floatation device, or the floatation device may be part of the level sensor 135. Thus, pressure may be applied to a sensor device which measures a level of water in the surge tank 130 in response to the applied pressure.

Fig. 4C shows a side view of the surge tank 130 from a front of the room view of the Fig. 4A , Again, three ports are visible at the top: the first outlet 132a, the second inlet 131b and the first inlet 131a, and laterally the second outlet 132b and the fourth outlet 130e are visible with the third inlet 131c hidden.

Fig. 4D shows a plan view of the surge tank 130, wherein again the first outlet 132a, the second inlet 131b, the first inlet 131a and laterally the third inlet 131c are visible.

Finally shows Fig. 4E a side view of that side of the surge tank 130, which is opposite to the side on which the third inlet 131c, the second outlet 132b and the port 130e are formed. Visible at the top is the first outlet 132a (see FIG. Fig. 4C ).

Further exemplary embodiments of the present invention thus relate in particular also to an expansion tank 130 for safe operation of a reverse osmosis system 120, which is integrated in a dishwasher.

Further advantageous aspects of the present invention can be summarized as follows.

As described above, at the rinsing machine inlet 10, there is, for example, a solenoid valve 162 (second valve means) with a flow regulator setting, for example, a predetermined volume per unit time (e.g., four liters per minute). Downstream of the valve 162 is the water technical safety device 150, which provides an air gap. The softener 110 is further connected in the flow direction. After the softener 110, the water flows into the compensation tank 130, which serves as a connecting element between the softener 110 and a downstream reverse osmosis system 120.

The task of the expansion tank 130 includes, for example, the synchronization of volume flows of an inflowing amount of water with an outflowing amount of water. This avoids, on the one hand, the over-build-up of the air gap in the system producing too much peeling water and, on the other hand, that the pump 170 cavitates due to the lack of water. Thus, therefore, a continuous operation of the pump 170 is achieved. Characterized in that the expansion tank 130 monitors a level of contained water and the entire system is electronically controlled, the conditions described above (idling and backwater) can not occur and the system can be operated in an optimal operating condition.

Another task of the expansion tank 130 is the degassing of the water flowing from the water softener 110. Since in the passage of the water through the softener 110 finely located gas bubbles are finely dispersed in the water and the downstream pump 170 should not cavitate, a better operation of the pump 170 is ensured by the degassing.

Another advantage of the invention is that the amount of peeling water that forms at the air gap is not zugleitet the boiler 300, but is forwarded via the surge tank 130, the pump 170 and thus to the reverse osmosis system 120. Only after demineralization does this water get into the boiler. This significantly increases the desired quality of water in the boiler.

Optionally, the dishwasher may thus also be operated with softened water (minimizing water consumption), in which case the surge tank 130 serves as an overflow to the boiler 300.

To achieve an always optimal water quality, the reverse osmosis system 120 can also be operated in such a way that, prior to the actual production of water, a so-called conductivity peak measurement is first carried out and a conductivity peak is minimized. This is done by the recovered permeate is fed back into the expansion tank 130 and the system is operated in the circuit. This minimizes water consumption overall.

To clean or preserve the reverse osmosis system 120, the required chemicals may be supplied to the surge tank 130 via a spigot 130e. As a result, they are led directly to the pump 170 via the outlet of the container 130, which can then forward the chemicals to the membrane 123 of the reverse osmosis system 120 and preserve or clean them.

Thus, embodiments of the invention further provide the advantage that a combination between an internal reverse osmosis system 120 in a dishwasher and a simultaneously upstream softening 110 is possible.

If no expansion tank 130 were connected upstream, the operational safety and function of the device could not be ensured because either the pump 170 of the reverse osmosis system 120 runs dry or too much peeling water is produced. In addition, a change between softened water and demineralized water to operate the dishwasher would not be possible.

If the synchronization of the volume flows via the expansion tank 130 should not be sufficient, a further synchronization of the volume flows via a speed control of the pump 170 could be made. In addition, in other embodiments, a two- or three-way valve could be used to supply softened water to either the reverse osmosis system or the boiler 300.

Further embodiments also relate to a control device that is designed to control a dishwasher described above. This control can be done, for example, as follows.

First, a filling of the surge tank 130 with softened water. Subsequently, depending on the selected wash program, the dishwasher can access either softened water or water from the reverse osmosis system 120 (optionally with or without a conductivity peak minimization). Thus, a gentle operation of the reverse osmosis system 120 is ensured because the controller recognizes when, for example, no regenerant has been introduced, and based on this, can bypass the bypass osmosis system 120 (using the bypass line 136). Advantageously, the dishwasher has only two connection hoses: a water inlet and a water outlet. With the reverse osmosis system 120, extended service lives of the individual components are to be expected. By a central control error messages of the reverse osmosis system 120 and the water softener 110 can be displayed on an optional display of the dishwasher. Thus, embodiments provide built-in softening, built-in reverse osmosis, conductivity peak minimization, and achieve optimal water quality.

Advantageously, by embodiments of the present invention, the components of the reverse osmosis system have a lower wear than conventional systems in which no choice of water quality is possible. In addition, a reduction in water consumption will result.

Thus, the dishwasher of the present invention reduces water consumption while improving the washing result.

In further embodiments, communication with external water treatment plants via a central control unit is possible. Optionally, an integrated replacement cartridge with ion exchange resin filling can be inserted into the dishwasher.

The first rinse program first prepares a tank of softened water. For this purpose, water is fed to the softener 110 from the inlet 10 of the machine via a solenoid valve (second valve device 162) and an air gap in the water-technical safety device 150. There is an ion exchange, so that the water is softened by the passage of the ion exchange resin (Ca ²⁺ - and Mg ²⁺ ions are removed from the liquid and replaced by Na ⁺ ions). Thereafter, the softened water flows into the surge tank 130 where it is supplied via an overflow / vent 132a to the boiler 300 of the machine. After heating to the setpoint temperature, it is pumped via the post-rinse pump (third pump 530) of the post-rinse device into the machine and finally into the rinsing chamber 400.

Another wash program relates to a dishwasher to be operated with softened or demineralized water, with the additional option of eliminating a conductivity peak prior to adding water to the boiler 300. In this mode of operation, the operation of the machine over softened water corresponds to the previously described mode. For operation of the machine with demineralized water, the incoming water to the surge tank 130 passes through the pump 170 into the reverse osmosis plant 120. The permeate produced thereby flows into the boiler 300 and is fed to the machine as described above. The optional conductivity peak is caused by the diffusion of the minerals in the concentrate of the reverse osmosis membrane 123 into the permeate. This is a time-consuming and temperature-consuming process. That is, the longer the standby time of the reverse osmosis system 120, the higher the initial permeate conductivity. By feeding the permeate via the peak valve (first valve device 161) into the expansion tank 130, over a certain parameterizable time, the conductivity in the permeate can be reduced so far that when closing the peak valve 161, the permeate directly in the desired quality of the boiler 300th supplied can be. From there, the water flows into the machine as described above.

Another mode of operation concerns the case where no regenerant has been introduced and bypass reverse osmosis can be bypassed (membrane gentle). In this case, when the built-in softener 110 is depleted of its capacity, it must be regenerated. Depending on the hardness of the water, this happens after a certain amount of liter has flowed through. The regeneration of the water softener 110 is carried out with a concentrated NaCl solution which is supplied to the softener 110 via the Besolungsventil 163 (third valve means). About the switching valve, the excess brine is then added to the sewage of the machine. So that the regeneration can take place, the salt container 200 (regenerant container) is filled with NaCl, which is then automatically dissolved in water via the water inlet. So that salt does not have to be replenished within short time intervals, the brine tank 200 is designed so that several regenerations can be carried out before it becomes empty.

When the vacancy of the salt container 200 is reached, the salt level sensor 210 gives a signal to the controller. This switches then, after the ion exchanger is exhausted, the reverse osmosis bypass, so that the inflowing water as described above via the surge tank 130 is placed directly in the boiler 300.

Another advantage is that only two connection hoses are needed, as by merging the wastewater of the water softener 110 with the wastewater from the drain pump 520 (second pump) in the wastewater aeration device 450 and downstream of the concentrate from the reverse osmosis 120 of the sewage hose all water flows can dissipate the machine.

Claims (13)

A dishwasher having a raw water connection (10) and a water treatment plant (100), the water treatment plant (100) comprising: a softener (110) adapted to soften the raw water from the port (10); a reverse osmosis system (120); and a surge tank (130) fluidly disposed between the water softener (110) and the reverse osmosis plant (120), the surge tank (130) providing a buffer for the softened water from the softener (110). The dishwasher of claim 1, wherein the surge tank (130) has an outlet (132a) for a bypass connection (136) for passage past the reverse osmosis system (120), the outlet (132a) on the surge tank (130) being arranged to supply air or to give softened water from the water treatment plant (100). The dishwasher of claim 1 or 2, wherein the reverse osmosis system (120) is adapted to separate water into a permeate used for purging and a retentate to be disposed of, and the dishwasher comprises a conductivity meter (140) for measuring a quality of the permeate and a return line ( 145) for returning the permeate to the surge tank (130), wherein the conductivity metering device (140) is arranged to conduct a conductivity measurement to determine the quality prior to a return of the permeate to the surge tank (130) via the return flow line (145). A dishwasher according to any one of the preceding claims, further comprising a regenerant container (200) connected to the softener (110) and providing a reservoir for a regenerant. The dishwasher of claim 4, wherein the regenerant container (200) includes a fill sensor (210) for measuring a brine concentration in the regenerant container (200). Dishwasher according to one of the preceding claims, further comprising a water technical safety device (150) fluid between the connection (10) for raw water and the softener (110), wherein the water technical safety device (150) an air gap and a connection for a water connection (155) so that the raw water before the supply to the softener (110) overcomes the air gap and the water connection (155) to the surge tank (130), bypassing the softener (110) is connected. The dishwasher of any one of the preceding claims, further comprising a pump (170) between the surge tank (130) and the reverse osmosis plant (120), the pump (170) configured to supply softened water at a predetermined pressure to the reverse osmosis plant (120) , Dishwasher according to one of the preceding claims, wherein the surge tank (130) further comprises a level sensor (135) for measuring a water level in the surge tank (130) and / or a port (130e) for draining and supplying maintenance means. The dishwasher of any one of the preceding claims, further comprising a softener effluent line (116) disposed between an outlet (110b) of the water softener (110) and a sewage port (20). A dishwasher according to any one of the preceding claims, when dependent on claim 2, further comprising a boiler (300) and the boiler (300) has a first inlet connected to the bypass connection (136) of the surge tank (130) and a second inlet Inlet to receive permeate from the reverse osmosis system (120) via a Permeatleitung (305). Dishwasher according to one of the preceding claims, further comprising a control unit, wherein the control unit is adapted to operating conditions of the water treatment plant (100) to detect and control, and the dishwasher further comprises as far as dependent on claim 3, a first valve device (161) for controlling a reflux along the return flow line (145), and / or a second valve means (162) at the raw water port (10), the second valve means (162) being adapted to provide a predefined volume flow of raw water to the water treatment plant (100); and or as recited in claim 4, third valve means (163) disposed between the regenerant container (200) and the water softener (110) and adapted to supply regenerated means to the softener (110) and / or as recited in claim 6 and claim 9, fourth valve means (164) disposed between the softener (110) and the surge tank (130), the fourth valve means (164) being arranged to controllably control an outlet (110b) of the Softener (110) to connect to the Enthärterabwasserleitung (116) or with the surge tank (130), wherein the control unit is designed to control and / or control the first valve device (161) and / or the second valve device (162) and / or the third valve device (163) and / or the fourth valve device (164) and / or the pump 170 To detect results of the conductivity measuring device (140). The dishwasher of claim 11, wherein the control unit is configured to perform at least one of the following functions: detecting a water level of the surge tank (130) and, based thereon, controlling the pump (170) and / or the second valve device (162) between the water technical safety device (150) and the raw water port (10) to a level in the surge tank ( 130) to keep constant; - Based on a conductivity measurement of the conductivity measuring device (140) by means of the first valve means (161) between the reverse osmosis system (120) and the surge tank (130) to effect a permeate reflux to such an extent or until the permeate reaches a predetermined target value for the conductivity ; - controlling the third valve means (163) such that softening of the softener (110) reaches a predetermined value; - as far as dependent on claim 10, selectively supplying the boiler (300) with softened water via the bypass line (136) or the permeate line (305) by controlling the pump (170) and / or the second valve device (162). Dishwasher according to claim 11 or 12, wherein the control unit is designed, without conducting a conductivity measurement, based on a parameter which depends on a standstill time or indicates a return time, by means of the first valve means (161) from the reverse osmosis system (120) to the surge tank 130th to obtain a permeate reflux for a reflux duration, which depends on the parameter.

Images