EP3988220A1 - Flushing apparatus and flushing method for liquid circuits - Google Patents

Abstract

The invention relates to an automatic rinsing machine for liquid circuits and a corresponding rinsing method. The dishwasher comprises a container (1), a pressure pump (2), a controllable four-way valve (3) and a control element (4) for controlling the pressure pump (2) and the four-way valve (3). The tank (1) is connected to the inlet (31) of the four-way valve (3). The four-way valve (3) comprises an inlet (31), an outlet (32), an inlet (33) and a return (34) and can be controlled between a forward position and a return position. In the forward position, liquid flowing in through the inlet (31) flows out of the inlet (33), and liquid flowing in through the return (34) flows out of the outlet (32). In the return position, liquid flowing in through the inlet (31) flows out of the return (34), and liquid flowing in through the inlet (33) flows out of the outlet (32).

Description

The present invention relates to an automatic rinsing machine for liquid circuits according to patent claim 1 and a corresponding rinsing method according to patent claim 7.

In heat pump heating systems, solar thermal systems or other systems for controlling the temperature in buildings, a mixture of two or more liquids is usually used in the liquid circuit, in particular an antifreeze mixture with water and antifreeze. Before start-up or as part of maintenance or repair, the liquid circuits must be flushed to remove gas bubbles, residues or other contaminants from the system before the liquid circuit is refilled.

For thorough rinsing, the liquid circuit is rinsed with a rinsing liquid by pre-rinsing and back-rinsing in both flow directions. A hose can be used for this, which is connected in series to both ends of the liquid circuit by means of water pressure or a pressure pump, so that flushing can take place in both directions. Changing the connections for pre-rinsing and back-rinsing, however, involves a lot of effort and causes liquid to leak out and splashes in the area, so that cleaning has to be done at the end.

For the new filling of the liquid circuit, the mixture, which ideally is already prepared in a container, must be filled into the circuit with the correct mixing ratio. In the case of a mixture consisting of a relevant part of water, it makes sense to first prepare the mixture on site so that only the additional liquids or substances have to be transported to the plant. On the one hand, this requires a mixing device and, on the other hand, the ratio of the liquids must be able to be measured/adjusted correctly.

The object of the present invention is now to provide a compact and transportable automatic rinsing machine for liquid circuits and a corresponding rinsing method with which a suitable mixture for liquid circuits can be prepared and liquid circuits can be rinsed easily and efficiently.

This task is solved by an automatic rinsing machine for liquid circuits with the features of patent claim 1 and a rinsing method with the features of patent claim 7. Further features and Exemplary embodiments emerge from the dependent claims and their advantages are explained in the following description.

Figur 1a

Spülautomat

Figur 1b

Ausführungsvariante des Vierwege-Ventils

Figur 2

Ausführungsvariante des Spülautomats mit Rücklaufschlaufe

Figur 3

Ausführungsvariante des Spülautomats mit Rücklaufschlaufe und Mischvorrichtung

The drawings show:

Figure 1a

dishwasher

Figure 1b

Design variant of the four-way valve

figure 2

Version of the dishwasher with return loop

figure 3

Version of the dishwasher with return loop and mixing device

The figures represent possible exemplary embodiments which are explained in the following description.

In the simplest embodiment of the invention, the dishwasher comprises a container 1, a pressure pump 2, a controllable four-way valve 3 and a control element 4 for controlling the pressure pump 2 and the four-way valve 3 ( Figure 1a ).

• einer Vorlaufstellung, in welcher eine durch den Einlass 31 einfliessende Flüssigkeit aus dem Zulauf 33 herausfliesst, und eine durch den Rücklauf 34 einfliessende Flüssigkeit aus dem Auslass 32 herausfliesst; und
• einer Rücklaufstellung, in welcher eine durch den Einlass 31 einfliessende Flüssigkeit aus dem Rücklauf 34 herausfliesst, und eine durch den Zulauf 33 einfliessende Flüssigkeit aus dem Auslass 32 herausfliesst.

The four-way valve 3 comprises an inlet 31, an outlet 32, an inlet 33 and a return 34 and can be adjusted between two positions:

• a preliminary position in which a through the liquid flowing in through the inlet 31 flows out from the inlet 33, and liquid flowing in through the return 34 flows out from the outlet 32; and
• a return position in which a liquid flowing in through the inlet 31 flows out of the return 34 and a liquid flowing in through the inlet 33 flows out of the outlet 32 .

The four-way valve 3 can be present in any embodiment of the invention either in the form of a single one-piece part, or consist of a first controllable and a second controllable three-way valve 35, 36 according to Figure 1b combined are connected. The inlet 31 and the outlet 32 are connected to both the first three-way valve 35 and the second three-way valve 36 . The first three-way valve 35 is also connected to the inlet 33 and the second three-way valve 36 is connected to the return 34 . The first three-way valve 35 can be set between two positions: a forward position, in which a liquid flowing in through the inlet 31 flows out of the inlet 33, and a return position in which a liquid flowing in through the inlet 33 flows out of the outlet 32. The second three-way valve 36 is also adjustable between two positions: a forward position in which a liquid flowing in through the return 34 flows out of the outlet 32, and a return position in which a liquid flowing in through the inlet 31 flows out of the return 34.

The pressure pump 2 is arranged between the container 1 and the four-way valve 3 . In special cases, a suction pump could alternatively be arranged after the outlet 32 of the four-way valve 3 .

In the preferred embodiment of the invention, the inlet 33 and the return 34 are provided with connections for connection to a liquid circuit, for example a heating circuit.

To flush a liquid circuit, the container 1 is first completely or partially filled with a liquid and the inlet 33 and the return 34 of the four-way valve 3 are connected to the liquid circuit. Then the liquid is conveyed by the pressure pump 2 from the container 1 to the four-way valve 3 and into the liquid circuit. The liquid emerging from the liquid circuit flows through the four-way valve 3 and, in the simplest embodiment of the invention, it leaves the Dishwasher through a drain 5. The changeover of the four-way valve 3 between the forward and reverse position also allows flushing in both directions of flow through the liquid circuit.

• Auffüllen des Behälters 1 mit einer Flüssigkeit;
• Verbindung des Zulaufs 33 und des Rücklaufs 34 des Vierwege-Ventils 3 mit dem Flüssigkeitskreislauf;
• Stellung des Vierwege-Ventils 3 in die Vor- oder Rücklaufstellung;
• Ansteuerung der Druckpumpe 2 und Spülung des Flüssigkeitskreislaufes für eine bestimmte Zeit in einer Fliessrichtung;
• Umstellung des Vierwege-Ventils 3 in die andere Stellung und Spülung des Flüssigkeitskreislaufes für eine bestimmte Zeit in der anderen Fliessrichtung.

A typical flushing method for a liquid circuit consists of the following steps:

• filling up the container 1 with a liquid;
• Connection of the inlet 33 and the return 34 of the four-way valve 3 to the liquid circuit;
• position of the four-way valve 3 in the forward or reverse position;
• Activation of the pressure pump 2 and flushing of the liquid circuit for a specific time in one direction of flow;
• Changeover of the four-way valve 3 to the other position and flushing of the liquid circuit for a certain time in the other direction of flow.

• einer Kreislaufstellung, in welcher eine durch den Ventileintritt 61 einfliessende Flüssigkeit aus dem ersten Ventilaustritt 62 in Richtung des Behälters 1 herausfliesst; und
• einer Ablaufstellung, in welcher eine durch den Ventileintritt 61 einfliessende Flüssigkeit aus dem zweiten Ventilaustritt 63 in Richtung des Ablaufs 5 herausfliesst.

In a particularly advantageous embodiment of the invention, the dishwasher also has a third controllable three-way valve 6 ( figure 2 ), which is located behind the outlet 32. The third three-way valve 6 includes a valve inlet 61, a first Valve outlet 62, which is connected to the container 1, and a second valve outlet 63 and can be controlled between two positions:

• a circulation position in which a liquid flowing in through the valve inlet 61 flows out of the first valve outlet 62 in the direction of the container 1; and
• an outflow position in which a liquid flowing in through the valve inlet 61 flows out of the second valve outlet 63 in the direction of the outflow 5 .

• ein Flüssigkeitsaustritt 11 des Behälters 1 führt zum Einlass 31 des Vierwege-Ventils 3;
• der Auslass 32 des Vierwege-Ventils 3 führt zum Ventileintritt 61 des dritten Dreiwege-Ventils 6;
• der erste Ventilaustritt 62 des dritten Dreiwege-Ventils 6 führt zu einem ersten Flüssigkeitseintritt 12 des Behälters 1. Diese Verbindung bildet eine Rücklaufschlaufe 13 zwischen dem dritten Dreiwege-Ventil 6 und dem Behälter 1;
• der zweite Ventilaustritt 63 des dritten Dreiwege-Ventils 6 führt zum Ablauf 5;
• die Druckpumpe 2 ist entweder zwischen dem Behälter 1 und dem Vierwege-Ventil 3 oder eine Saugpumpe ist zwischen dem Vierwege-Ventil 3 und dem dritten Dreiwege-Ventil 6 angeordnet.

In the variant of the dishwasher with the third three-way valve 6, the container 1, the pressure pump 2, the four-way valve 3 and the third three-way valve 6 are connected to one another as follows:

• a liquid outlet 11 of the container 1 leads to the inlet 31 of the four-way valve 3;
• the outlet 32 of the four-way valve 3 leads to the valve inlet 61 of the third three-way valve 6;
• the first valve outlet 62 of the third three-way valve 6 leads to a first liquid inlet 12 of the container 1. This connection forms a return loop 13 between the third three-way valve 6 and the container 1;
• the second valve outlet 63 of the third three-way valve 6 leads to the outlet 5;
• the pressure pump 2 is arranged either between the tank 1 and the four-way valve 3 or a suction pump is arranged between the four-way valve 3 and the third three-way valve 6.

Each mentioned connection between the tank 1, the pressure pump 2, the four-way valve 3 and the third three-way valve 6 can be direct or comprise further elements coupled in between.

The rinsing takes place in the same way as in the simplest embodiment variant of the dishwashing machine without a third three-way valve 6 with the difference that the liquid emerging from the liquid circuit is passed through the four-way valve 3 to the third three-way valve 6 this time. The third three-way valve 6 is either in the drain position, in which the liquid exiting the liquid circuit leaves the dishwasher, or in the circulation position, in which the liquid exiting the liquid circuit returns to the container 1 via the return loop 13. This last option is special advantageous because the liquid emerging from the liquid circuit is used again and again for flushing and can be conveyed through the liquid circuit as often as desired. This enables thorough flushing of any length with minimal liquid consumption.

• Auffüllen des Behälters 1 mit einer Flüssigkeit;
• Verbindung des Zulaufs 33 und des Rücklaufs 34 des Vierwege-Ventils 3 mit dem Flüssigkeitskreislauf;
• Stellung des Vierwege-Ventils 3 in der Vor- oder Rücklaufstellung und des dritten Dreiwege-Ventils 6 in der Kreislaufstellung;
• Ansteuerung der Druckpumpe 2 und Spülung des Flüssigkeitskreislaufes für eine bestimmte Zeit in einer Spülrichtung;
• Umstellung des Vierwege-Ventils 3 in der anderen Stellung und Spülung des Flüssigkeitskreislaufes für eine bestimmte Zeit in einer anderen Spülrichtung.

In this embodiment of the dishwasher, a typical flushing method for a liquid circuit includes the following steps:

• filling up the container 1 with a liquid;
• Connection of the inlet 33 and the return 34 of the four-way valve 3 to the liquid circuit;
• position of the four-way valve 3 in the advance or return position and the third three-way valve 6 in the circuit position;
• Activation of the pressure pump 2 and rinsing of the liquid circuit for a specific time in a rinsing direction;
• Changeover of the four-way valve 3 in the other position and flushing of the liquid circuit for a certain time in a different flushing direction.

If the escaping from the liquid circuit Liquid for rinsing is no longer to be used, the third three-way valve 6 can be switched to the drain position at any time before, during or after rinsing. In the drain position, the liquid runs from the container 1 only once through the liquid circuit and then leaves the dishwasher through the drain 5. This is particularly advantageous if the liquid emerging from the liquid circuit does not meet certain requirements for its further use in the rinsing method. These requirements are set by the user and can be, for example, a threshold for the maximum permissible concentration of impurities in the liquid. If this threshold is exceeded, the liquid emerging from the liquid circuit can no longer be used for flushing or filling, and the third three-way valve 6 can be set to the drain position. Otherwise, the third three-way valve 6 can be set to the circulation position in order to continue using the liquid emerging from the liquid circuit for flushing or filling. For example, before flushing, a soiled liquid that is already present in the liquid circuit can first be removed from the liquid circuit and the dishwasher. At the end of the flushing, the liquid contaminated by the flushing can also be removed before the Liquid circuit is refilled. It is also conceivable to use different liquids for flushing and for refilling the liquid circuit after flushing. In this case, the rinsing liquid must be removed from the liquid circuit at the end of the rinsing before the desired filling mixture can be introduced. However, the rinsing preferably takes place with the new filling mixture, so that the liquid circuit is already refilled at the end of the rinsing.

When flushing with the third three-way valve 6 in the recirculation position, the container 1 serves not only to receive the liquid before it is sent through the liquid circuit again, but also to remove gas bubbles or impurities that are in the liquid circuit. For this, the container 1 must be high enough and wide enough that the gas bubbles present in the incoming liquid can rise to the liquid surface without being entrained by the liquid flow to the liquid outlet 11 . Preferably, an open container 1 is used under atmospheric pressure, so that gases can escape into the environment when flowing through the container 1, while the gas-free liquid through the pressure pump 2 from the liquid outlet 11 in the lower Area of the container 1 is sucked. In the case of impurities, they can sink in the container due to the force of gravity, in which case it makes sense for the liquid outlet 11 of the container to be arranged above the area in which impurities can settle. In the preferred embodiment, the container 1 has a capacity of about 20 liters. It is also conceivable to use a closed container 1, with gases being collected as they flow through the container 1 in the upper region of the container 1.

In an advantageous embodiment variant of the invention, a filter 7 is provided on the liquid flow path, which filter rids the liquid circuit of harmful components that can damage valves, boilers, pumps, etc. The filter 7 can be a physical filter for solid particles and other solid residues, eg a magnetic flux filter. In addition or instead, the filter 7 can be a chemical filter for demineralization, in particular for removing lime, and/or for protection against corrosion, in particular for removing aggressive gases such as oxygen, and/or for pH regulation. Suitable chemical filters consist, for example, of ion exchange resin or of a sacrificial anode in the form of replaceable disposable cartridges may exist. The filter 7 is preferably arranged in the container 1 in the vicinity of the liquid outlet 11 or between the container 1 and the pressure pump 2 .

In another embodiment of the invention, after the outlet 32 of the four-way valve 3, means 8 are provided for measuring physical properties of the liquid exiting the liquid circuit. These measuring means 8 are, for example, a transparent area in the line, which, depending on the variant, leads directly to the outlet 5 or initially to the third three-way valve 6, so that the user can visually recognize the optical properties of the liquid, e.g. the presence of gas bubbles and Impurities, the color and clarity of the liquid, etc. These measuring means 8 can also be a refractometer or a turbidity sensor or other sensors which are connected to the control element 4 and automatically measure or monitor optical properties of the liquid exiting the liquid circuit. Thanks to these measuring means 8, for example, the right point in time for switching the four-way valve 3 between the forward and reverse position can be determined. In the embodiment variant of the dishwasher with the third three-way valve 6, the measuring means 8 can be used to check whether the Liquid meets the requirements for its further use in the flushing method or not, and the third three-way valve 6 can be controlled accordingly.

In a further embodiment variant, the automatic dishwashing machine includes a mixing device for preparing and filling the container 1 with a mixture which is then used for rinsing and filling the liquid circuit ( figure 3 ). In the simplest embodiment variant, the mixing device consists of a water line 91, a controllable water valve 92, an injector nozzle 93, a suction line 94 and a mixture line 95. The water valve 92 is connected on the one hand to the water line 91 and on the other hand to the injector nozzle 93 and controls the water supply from the water line 91 to the injector nozzle 93. The injector nozzle 93 is used to mix the water from the water line 91 with a liquid or powder additive from the suction line 94, in particular an antifreeze, to produce a mixture. The mixture produced passes from the injector nozzle 93 through the mixture line 95 into the container 1. It is particularly advantageous if the injector nozzle 93 is a Venturi nozzle in which the diameter of the water supply is reduced by the pressure To accelerate water from the water line 91. According to the Venturi principle creates a suction in the suction line 8, so that the flowing water is mixed with a certain amount of additive, typically around 15-30% additive in the water. Higher mixing ratios of up to 50% additive can also be achieved by an additional reduction in the diameter of the water supply and correspondingly greater acceleration of the water in front of the mouth of the suction line 94 in the injector nozzle 93. This creates a stronger suction with which the water more additive is added. Even better is the use of two or more suction lines 8, which ideally are arranged regularly around the injector nozzle 93.

It is advantageous if an additive for leak sealing is added to the mixture used for flushing and filling the liquid circuit. Such additives seal small cracks, brittle seals and leaking solder joints in corroded lines.

The main advantage of the mixing device in the dishwasher is that the mixture of water and additive can only be prepared on site, in exactly the right amount and with the right mixing ratio. This means that only the concentrated additive needs to be transported to the plant and not the entire prepared mixture. To the To prepare the mixture and to fill up the container 1, the water line 91 is connected to a conventional water supply with pressurized water, for example a domestic water line, and the end of the suction line is immersed in a container with liquid or powder additive. The water valve 92 is then opened by the control element 4, additive is mixed with the water in the injector nozzle 93 and the container 1 is completely or partially filled with the mixture. In a possible embodiment variant, the control element 4 monitors the fill level of the container 1 with a float 96 which is arranged in the container 1. FIG. As soon as a defined filling level is reached, the water valve 92 is automatically closed by the control element 4 and the filling of the container 1 is stopped.

In further embodiment variants of the mixing device, a water meter 97 and/or a pressure reducer 98 is provided on the water line 91. The water meter 97 is preferably arranged upstream of the water valve 92, and the pressure reducer 98 is preferably arranged between the water valve 92 and the injector nozzle 93.

In possible variants of the dishwasher, the container 1 is provided with an agitator and/or with a heater and/or with a float valve 99 . That Agitator ensures better uniformity of the mixture in vessel 1. The heater is used to control the temperature of the mixture in vessel 1 and may be an immersion heater or a sump heater, eg in the form of an electric heater band, or a heat exchanger conducted through a medium. The float valve 99 serves to prevent overfilling of the tank 1. It could be placed in the tank 1 at the mouth of the first liquid inlet 12 to allow access to the return loop 13 when the liquid level reaches the first liquid inlet 12. In this embodiment variant, the third three-way valve 6 can assume a third position in which a liquid flowing in through the first valve outlet 62 flows out of the second valve outlet 63 to the outlet 5 .

It is particularly advantageous if the control element 4 has a user interface through which the various controllable components of the dishwasher can be controlled manually and/or automatic programs can be initiated. Possible user interfaces are, for example, a touch screen and/or pushbuttons, etc. The methods described above for preparing the mixture, for filling the container 1 and for flushing and filling the liquid circuit can be stored as a program in control element 4 and run fully automatically.

Claims (10)

Flushing machine for liquid circuits comprising: • a container (1) with a liquid outlet (11), • a pressure pump (2), • a controllable four-way valve (3) with an inlet (31), an outlet (32), an inlet (33) and a return (34), and • a control element (4) for controlling the pressure pump (2) and the four-way valve (3), wherein the liquid outlet (11) of the container (1) leads to the inlet (31) of the four-way valve (3), and the pressure pump is arranged between the container (1) and the four-way valve (3),
characterized in that
the four-way valve (3) can be controlled between two positions: • an advance position in which a liquid flowing in through the inlet (31) flows out of the inlet (33) and a liquid flowing in through the return (34) flows out of the outlet (32); and • A return position, in which a liquid flowing in through the inlet (31) flows out of the return (34), and one through the inlet (33) inflowing liquid flows out of the outlet (32). Dishwasher according to claim 1, characterized in that the four-way valve (3) consists of a first controllable and a second controllable three-way valve (35, 36) connected in combination. Dishwasher according to claim 1, marked by a third three-way valve (6) which can be controlled by the control element (4) and has a valve inlet (61), a first valve outlet (62) and a second valve outlet (63), the third three-way valve (6) being controllable between two positions: • a circulation position in which a liquid flowing in through the valve inlet (61) flows out of the first valve outlet (62); and • an outflow position in which a liquid flowing in through the valve inlet (61) flows out of the second valve outlet (63), and wherein the container (1), the four-way valve (3) and the third three-way valve (6) are connected to each other as follows: • the outlet (32) of the four-way valve (3) leads to the valve inlet (61) of the third three-way valve (6); • the first valve outlet (62) of the third three-way valve (6) leads to a first liquid inlet (12) of the container (1), this connection forms a return loop (13) between the third three-way valve (6) and the container ( 1); • The second valve outlet (63) of the third three-way valve (6) leads to an outlet (5). Dishwasher according to claim 1, marked by a physical filter (7) for solid particles and residues and/or a chemical filter for scale and/or oxygen and/or for pH regulation, placed either in the tank (1) or between the tank (1) and the pressure pump (2 ) is arranged. Dishwasher according to claim 1, characterized in that after the outlet (32) of the four-way valve (3), means (8) are provided for measuring physical properties of the liquid exiting the liquid circuit, in particular a transparent area in a line and/or a refractometer or turbidity sensor. Dishwasher according to claim 1, marked by a mixing device comprising a water pipe (91), a controllable water valve (92), an injector nozzle (93), a suction line (94) and a mixture line (95), the water valve (92) being connected on the one hand to the water line (91) and on the other hand to the injector nozzle (93), wherein the injector nozzle (93) is suitable for mixing liquids in the water line (91) and in the suction line (94), and the mixture line (95) leading from the injector nozzle (93) to the container (1). Flushing method for a liquid circuit with the dishwasher according to claim 1,
comprising the following steps: • Filling up the container (1) with a liquid; • Connection of the inlet (33) and the return (34) of the four-way valve (3) with a liquid circuit; • position of the four-way valve (3) in the forward or reverse position; • Activation of the pressure pump (2) and flushing of the liquid circuit for a specific time in one direction of flow; and • Conversion of the four-way valve 3 to the other position and flushing of the liquid circuit for a certain time in the other flow direction. Flushing method according to claim 7 with the dishwasher according to claim 3, characterized in that the third three-way valve (6) before, during or after flushing: • placed in the drain position when the liquid exiting the liquid circuit does not meet certain requirements for its further use in the flushing method, and • is placed in the circulation position when the liquid emerging from the liquid circuit meets certain requirements for its further use in the flushing method. Flushing method according to claim 7 with the dishwasher according to claim 5, characterized in that physical properties of the liquid exiting the liquid circuit are measured during flushing to determine: • whether or not the liquid leaving the liquid circuit meets certain requirements for its further use in the flushing method; and or • the right moment for switching the four-way valve (3) between the forward and reverse position; and or • the right time to end the flush. Flushing method according to claim 7 with the dishwasher according to claim 6,
including the following additional steps: • Connection of the water pipe (91) to an existing water connection on site; • immersing the end of the suction line (94) in a container with additive; and • Open the water valve (92) and fill the tank (1) with a mixture of water and additive.

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