EP4141163A1 - Laundry dryer with a heat exchanger cleaning system - Google Patents

Abstract

A dryer, in particular a household tumble dryer, comprises a drum (2) for holding textiles and a heat pump with a condenser (5) and an evaporator (4). Air circulates through the drum (2), condenser (5) and evaporator (4) to dry the fabrics placed in the drum (2). The condensate water which is separated off at the evaporator (4) is collected in a first collection tank (6). The collected condensate water is used to wash down the evaporator (4).

Description

field of invention

The invention relates to a dryer, in particular a household tumble dryer. This includes a drum for holding textiles and a heat pump with a condenser and an evaporator. Air circulates through the drum, condenser and evaporator. This removes moisture from the textiles. In addition, the dryer includes a first collection container for collecting condensate, which is separated at the evaporator.

background

The air circulating in the dryer not only removes moisture as it flows through the drum, but also pulls fluff from the textiles. Classic dryers therefore provide fluff filters to filter the fluff out of the air flow. This prevents the heat pump's heat exchangers from becoming contaminated with fluff. Lint deposits on the heat exchangers affect the performance of the heat exchangers.

A lint filter does not work perfectly. A small amount of fluff penetrates the fluff filter. For this reason, several filter stages are provided in classic dryers. The first filter stage must be cleaned regularly by the user, preferably after each drying process. Other filter stages are slightly covered with fluff, so that they rarely have to be cleaned by a service technician. Nevertheless, calling in a service technician is tedious.

Presentation of the invention

The object is to provide a dryer which can be easily maintained.

• eine Trommel zur Aufnahme von Textilien;
• eine Wärmepumpe mit einem Kondensator und mit einem Verdampfer;
• ein Luftzirkulationssystem zur Zirkulation von Luft durch die Trommel, den Kondensator und den Verdampfer zur Trocknung der Textilien in der Trommel. Der Verdampfer kühlt die vorbeiströmende Luft ab, sodass die Feuchtigkeit aus der Luft kondensiert. Die am Verdampfer entnommene Wärmeenergie wird der Luft über den Kondensator wieder zugeführt, damit möglichst warme und trockene Luft in die Trommel strömt.
• einen ersten Sammelbehälter zum Sammeln von Kondensat, welches am Verdampfer abgeschieden wird. Insbesondere ist dieser erste Sammelbehälter zumindest teilweise unterhalb des Kondensators angeordnet. Dadurch kann im ersten Sammelbehälter auch dasjenige Kondensatwasser gut gesammelt werden, welches zur Reinigung des Kondensators verwendet wurde.

This object is solved by the subject matter of the independent claim. Accordingly, the dryer, in particular the household tumble dryer,

• a drum for receiving textiles;
• a heat pump with a condenser and with an evaporator;
• an air circulation system to circulate air through the drum, condenser and evaporator to dry the fabrics in the drum. The evaporator cools the air flowing past, causing the moisture in the air to condense. The heat energy extracted from the evaporator is returned to the air via the condenser so that the warmest and dryest possible air flows into the drum.
• a first collecting tank for collecting condensate, which is separated at the evaporator. In particular, this first collection container is arranged at least partially below the condenser. As a result, the condensate water used to clean the condenser can also be easily collected in the first collection tank.

The dryer includes a cleaning system for cleaning the front surface of the evaporator. The cleaning system uses the condensate collected in the first collection tank for cleaning.

The cleaning system has the advantage that the front surface of the evaporator, on which fluff is deposited, can be washed off using the collected condensate water. Depending on the cleaning performance, a fluff filter can be completely dispensed with, or the number of filter stages can be reduced. For example, only a single filter stage is provided, which can be cleaned by the user.

In particular, the first collection container includes a level sensor. This can be used to measure the level of the condensate in the first collection tank. If the fill level is high enough, the controller can start cleaning the evaporator.

• sich zumindest vom Verdampfer bis zur Rotationsachse der Trommel hoch oder bis oberhalb der Trommel erstreckt, und/oder
• die Zuleitung sich über eine Höhe von mindestens 30 cm, insbesondere mindestens 40 cm erstreckt.

The cleaning system advantageously has a feed line through which condensate water is fed from the first collection container to the evaporator, the feed line

• extends at least from the evaporator up to the axis of rotation of the drum or to above the drum, and/or
• the supply line extends over a height of at least 30 cm, in particular at least 40 cm.

With this configuration, the supply line extends over as great a vertical height as possible within the dryer. This has the advantage that condensate water conveyed from the first collection container into the supply line and can be stowed in this over as great a height as possible. The higher the water is dammed, the higher the hydrostatic pressure in the condensate. A high hydrostatic pressure has the advantage that the accumulated water can be flushed over the evaporator in surges. This causes a good cleaning result. A significant amount of fluff can be washed off the evaporator as a result.

The supply line advantageously includes an opening mechanism with a first opening which can be opened and closed. The opening mechanism serves to dam the condensate water in the supply line when the opening is closed. If the condensate water is backed up and the first opening opens, the backed up condensate water flows in surges over the evaporator.

In particular, the opening mechanism includes a flap. With this, the opening can be opened and closed, in particular abruptly.

In particular, the first openable opening is arranged at the end of the feed line. The "end" means the end of the supply line where the condensate water flows out of the supply line. If the opening that can be opened is arranged at this end, the condensate water can be dammed over the entire length of the supply line. A correspondingly high hydrostatic pressure is generated.

The first opening is advantageously arranged directly above the evaporator, in particular above the front surface of the evaporator. The accumulation of the condensate begins immediately above the evaporator. This measure also aims to ensure that the condensate water can be dammed up in the supply line over as great a height as possible.

Part of the first opening is preferred, in particular at least a third, in particular the Half of the first opening, located in front of the front surface and at the same time above the front surface of the evaporator. "In front of" the front face is to be understood in relation to the flow direction of the air, ie upstream of the front face or where the air flows before it enters the evaporator. The condensate water can thus be routed from the outside to the front surface. This leads to effective cleaning because the fluff is mainly deposited on the front surfaces.

In particular, the first opening extends over the entire top of the front surface of the evaporator. The total surface corresponds to the total width of the front face. If the opening extends over the entire width of the front surface of the evaporator, the condensate water can be backed up over the entire width of the front surface behind the openable first opening. As a result, when the first opening is opened, condensate water is flushed evenly over the entire front surface. A complete cleaning of the front surface can be achieved in this way.

The first opening is advantageously an elongate gap and in particular has a single opening area. In other words, the condensate water is not sprayed onto the front surface of the evaporator through a plurality of nozzles, but the condensate water flows over the entire width of the opening and uniformly cleans the front surface of the evaporator.

In particular, the opening mechanism is designed to completely open the first opening abruptly, ie in particular within a maximum of two seconds, in particular within a maximum of one second, in particular within a maximum of 0.5 second, in particular within a maximum of 0.2 second. A sudden opening has the advantage that the largest possible amount of condensate flows over the front surface of the evaporator within a short time. This causes an effective cleaning.

The opening mechanism advantageously has a second opening which is arranged above the condenser. Condensate water, which is used to clean the condenser, can flow through this opening. In particular, the front surface of the condenser is cleaned. The condenser is generally less dirty than the evaporator because the air first flows through the evaporator and only then through the condenser. Nevertheless, it should also be possible to clean the condenser in order to further reduce the maintenance work on the dryer.

In particular, the supply line separates into a first sub-line and a second sub-line. The first branch pipe directs the condensate water to the first opening and the second branch pipe directs the condensate water to the second opening. This means that the same supply line can be used for storing the condensate both for the evaporator and for the condenser.

The condensate water routed to the condenser is preferably collected in the first collection container after the condenser has been cleaned. As a result, the condensate water, which is already slightly contaminated with fluff, can be used again to clean the heat exchanger.

• in einem ersten Schritt das Kondensatwasser vom ersten Sammelbehälter in die Zuleitung gepumpt wird,
• in einem zweiten Schritt durch Öffnen der zweiten Öffnung der Kondensator gereinigt wird und das Kondensatwasser nach der Reinigung in den ersten Sammelbehälter geleitet wird,
• in einem dritten Schritt das im ersten Sammelbehälter gesammelte Kondensatwasser erneut in die Zuleitung gepumpt wird,
• in einem vierten Schritt durch Öffnen der ersten Öffnung der Verdampfer gereinigt wird. Somit kann das Kondensatwasser sowohl zur Reinigung des Kondensators als auch zur Reinigung des Verdampfers verwendet werden.

In particular, the dryer includes a cleaning program which is designed such that

• in a first step, the condensate water is pumped from the first collection tank into the supply line,
• in a second step, the condenser is cleaned by opening the second opening and the condensate water is fed into the first collection tank after cleaning,
• in a third step, the condensate water collected in the first collection tank is pumped back into the supply line,
• in a fourth step, the evaporator is cleaned by opening the first opening. So can the condensate water can be used both to clean the condenser and to clean the evaporator.

The dryer advantageously includes a second collection container. This is arranged in such a way that the condensate water routed to the evaporator is collected in the second collection tank after the front surface of the evaporator has been cleaned. In particular, the dryer includes a pump with which the condensate water collected in the second collecting tank can be pumped into the drain. This means that the condensate water, which is heavily soiled with fluff, is not used for renewed cleaning. It goes down the drain.

In an alternative embodiment, the condensate water routed to the evaporator is flushed directly into the drain after the front surface of the evaporator has been cleaned. This means that the condensate water is not collected in the collection tank for a long period of time.

The dryer advantageously includes access for the user to fill the first collection container with water, in particular with the first collection container having a volume of at least one liter, in particular at least two liters. If the evaporator is very dirty but there is not enough condensate water available to clean it, the user can fill additional water into the first collection tank so that cleaning is possible immediately.

Preferably, the dryer includes a single lint filter with a single filter stage. Further filter stages can be dispensed with. Because the filtering does not have to be particularly effective because the heat exchangers can be washed off.

Brief description of the drawings

• Fig. 1 einen Haushaltswäschetrockner in schematischer Darstellung;
• Fig. 2 ein Reinigungssystem des Haushaltswäschetrockners zur Reinigung von Verdampfer und Kondensator;
• Fig. 3 zeigt das Reinigungssystem gemäss Fig. 2 mit Sicht von oben;
• Fig. 4 zeigt die Zuleitung des Reinigungssystems;
• Fig. 5 zeigt den Öffnungsmechanismus und eine schematische Darstellung weiterer Komponenten.

Further configurations, advantages and applications of the invention result from the dependent claims and from the following description based on the figures. show:

• 1 a household tumble dryer in a schematic representation;
• 2 a household tumble dryer cleaning system for cleaning the evaporator and condenser;
• 3 shows the cleaning system according to 2 with view from above;
• 4 shows the supply line of the cleaning system;
• figure 5 shows the opening mechanism and a schematic representation of other components.

way of carrying out the invention

1 shows a domestic tumble dryer shown schematically. This comprises a housing 1 with a door 1a, a drum 2 (shown in dashed lines) with an axis of rotation 21 and a base area 3 arranged below the drum 2. In the base area 3 are an evaporator 4, a condenser 5, a first collection container 6 and a second Collection container 7 arranged. Evaporator 4 and condenser 5 are part of a heat pump.

The user fills the drum 2 with damp laundry to dry. During drying, air flows through the drum 2 and removes moisture from the laundry. The humid air flows through the evaporator 4 and is thereby cooled. The humid air condenses. The condensate water is collected in the first collection tank 6. The dashed arrow shows how the condensate water flows from the evaporator 4 to the first collection container 6 .

During drying, the flowing air not only removes moisture from the laundry. The air also removes fluff from the laundry. If a large amount of fluff is deposited on the evaporator 4 or the condenser 5, the process air flow is reduced, as a result of which the heat pump process can no longer be operated optimally. The humid air can only be cooled with difficulty at the evaporator 4 and can therefore only be dried with difficulty. For this reason, the deposition of lint on the evaporator 4 and the condenser 5 must be prevented.

Classic tumble dryers have a lint filter that filters the lint out of the air flow. However, a lint filter does not work perfectly. A few fluffs penetrate him. For this reason, there are usually several filter stages. The more filter stages there are, the greater the maintenance effort for the tumble dryer. Each individual filter stage must be cleaned.

The household tumble dryer according to 1 comprises only a single filter stage. This reduces the maintenance effort compared to classic tumble dryers. However, since the only filter stage does not work perfectly, fluff is primarily deposited on the evaporator 4, but also on the condenser 5. Evaporator 4 and condenser 5 must therefore be cleaned regularly.

A cleaning system is provided for this cleaning. This transports the condensate water collected in the first collecting container 6 via the pump line 8 to the feed line 9. The condensate water is conveyed from the feed line 9 to the evaporator 4 and the condenser 5 in order to wash them off.

In the 1 it can be seen that the feed line 9 extends from above the evaporator 4 to the top of the drum 2 . The supply line 9 thus also extends above the axis of rotation 21. The supply line 9 is over 40 cm long and extends over a significant part of the overall height of the household tumble dryer.

On the underside of the lead 9 is an opening mechanism 10 (illustrated in more detail in 2 and figure 5 ) arranged, which has a first opening 101 and a second opening 102. The openings 101 and 102 have flaps 103 and 104 with which the openings 101 and 102 can be opened and closed.

If the openings 101 and 102 are closed, condensate water can be backed up inside the feed line 9. Since the feed line 9 is designed to be correspondingly high, a correspondingly high hydrostatic pressure is produced at the openings 101 and 102 . A high hydrostatic pressure has the advantage that the backed-up condensate water flows in surges over the evaporator 4 as soon as the openings 101 and 102 are opened. Thereby, the lint deposited on the evaporator 4 and the condenser 5 can be washed off effectively.

The 2 shows the opening mechanism 10 arranged above the evaporator 4 and condenser 5 and the feed line 9 in a three-dimensional view. Also visible is the pump line 8, via which condensate water is pumped from the first collection container 6 to the supply line 9. An overflow line 11 is also arranged directly next to the supply line. As soon as the supply line 9 is completely filled with condensate water, the excess condensate water runs through the overflow line 11 into the drain.

In relation to the pump line 8, the feed line 9 has a significantly larger tube profile. The large tube profile enables the largest possible amount of condensate water to be dammed up in the supply line 9 . At the lower end of the feed line 9, the feed line has a shoe shape. This shoe shape extends over the entire width of evaporator 4 and condenser 5. In 3 this shoe shape 3a is more visible.

The opening mechanism 10 includes an actuator 105 which can open and close the flaps 103 and 104 via connecting elements 106 .

3 shows the device according to 2 with view from above. Shown are the feed line 9, the lower end 91 of the feed line 9 in the shape of a shoe and the flaps 103 and 104. The flaps extend in their length L (marked with the double file) over the entire width of the evaporator 4 arranged below the opening mechanism 10 and of the Condenser 5. The shoe shape of the lower end 91 of the supply line 9 distributes the condensate water over the entire length L. The closed flaps 103 and 104 thus accumulate condensate water over their entire width.

4 shows a section through the in 3 device shown. The cutting line is in 3 marked with the letter A. Visible are the inner areas of the pump line 8, the supply line 9 and the overflow line 11. The overflow line 11 begins at the upper end of the supply line 9, which is why the supply line 9 can accumulate condensate water up to its upper end.

figure 5 shows a section through the opening mechanism 10 and through the lower end 91 of the supply line 9. The section line is in 3 marked with the letter B. Furthermore, in figure 5 shown in a schematic representation of the evaporator 4, the condenser 5, the first collecting container 6, the second collecting container 7 and a fluff filter 12 with a single filter stage.

The dashed arrows show the air flow. The air flows through the lint filter 12, the evaporator 4 and the condenser 5. The other arrows show the flow of condensate water. Condensate water separated in the evaporator flows into the first collection container 6. From there, the condensate water is pumped into the supply line 9 and accumulated behind the flaps 103 and 104. If the flaps 103 and 104 are opened, it flows the condensate water through the first opening 101 and then over the front surface of the evaporator 4 or through the second opening 102 and then over the front surface of the condenser 5.

The first opening 101 is arranged directly above the front face 41 of the evaporator 4 . The second opening 101 is arranged immediately above the front face 51 of the condenser 5 . In addition, the supply line 9 comprises two partial lines 92 and 93, which lead the condensate water to the openings 101 and 102, respectively.

The front surface 41 is arranged centrally below the first opening 101, so that the front surface 41 is very effectively washed off when there is a flow vertically downwards. Incidentally, the first opening 101 and the second opening 102 are designed as an elongated gap. The gap or openings 101 and 102 and also the respective flaps 103 and 104 extend over the length L as shown in FIG 3 is drawn. The length L corresponds to the entire width of the evaporator 4 and the condenser 5.

A cleaning process runs as follows. The condensate water separated at the evaporator 4 and collected in the first collection container 6 is transported via the pump line 8 into the feed line 9 . In the opening mechanism 10, the flaps 103 and 104 are closed. The condensate accumulates in the supply line 9.

As soon as enough condensate water has accumulated in the supply line 9, the control of the household tumble dryer opens the second flap 104 abruptly. Condensate water flows through the second opening 102 onto the front surface of the condenser. In this case, the condensate water is only slightly contaminated with fluff because basically only a small amount of fluff is deposited on the front surface 51 of the condenser 5 . The condensate water, which is only slightly contaminated with fluff, is returned to the collection container 6 collected and pumped again via the pump line 8 into the feed line 9.

If the condensate water is backed up in the supply line 9, the controller suddenly opens the first flap 103 and the condensate water flows through the first opening 101 over the front surface 41 of the evaporator 4. The condensate water, which is now heavily contaminated with fluff, is collected in the second collection container 7 and then pumped the drain.

In order to achieve the best possible cleaning result, the flaps 103 and 104 are opened abruptly. As a result, the accumulated condensate flows in surges over the front surfaces 41 and 51.

In the event that the evaporator 4 and condenser 5 have to be cleaned, but there is not enough condensate water available, a filling opening 13 (shown in Fig 1 ) be provided, through which the user can fill water into the first collection container 6.

While the present application describes preferred embodiments of the invention, it is to be understood that the invention is not limited thereto and may be otherwise embodied within the scope of the following claims.

Claims (15)

Dryer, in particular a household tumble dryer, comprising - a drum (2) for receiving textiles, - a heat pump with a condenser (5) and an evaporator (4), - an air circulation system for circulating air through the drum (2), the condenser (5) and the evaporator (4) for drying the textiles in the drum (2), - A first collection container (6) for collecting condensate, which is deposited on the evaporator (4), characterized in that the dryer has a cleaning system for cleaning the front surface (4a) of the evaporator (4) using the condensate collected in the first collecting tank (6). Dryer according to Claim 1, in which the cleaning system has a feed line (9) through which condensate water is fed from the first collecting container (6) to the evaporator (4). Dryer according to claim 2, wherein the supply line (9) - extends at least from the evaporator (4) up to above the axis of rotation (21) of the drum (2) or at least up to the top of the drum (2), and/or - extends over a height of at least 30 cm, in particular at least 40 cm. Dryer according to one of claims 2 or 3, wherein the supply line (8) has an opening mechanism (10) having a first opening (101) that can be opened, designed in order to dam the condensate water in the supply line (8) when the first opening (101) is closed,
in particular wherein the opening mechanism (10) has a flap (103) for opening and closing the first openable opening (101). A dryer according to claim 4, wherein - the first opening (101) is arranged at the end of the supply line (8), and/or - The first opening (101) is arranged directly above the evaporator (4), in particular above the front surface (41) of the evaporator (4). Dryer according to one of claims 4 or 5, wherein part of the first opening (101), in particular at least one third, in particular half of the first opening (101), is arranged in front of the front surface (41) of the evaporator (4). Dryer according to one of claims 4 to 6, wherein the first opening (101) extends over the entire top of the front surface (41) of the evaporator (4),
in particular wherein the first opening (101) is an elongate slot and in particular has a single opening area. Dryer according to one of claims 3 to 7, wherein the opening mechanism (10) is designed to open the first opening (101) abruptly, i.e. in particular within a maximum of two seconds, in particular within a maximum of one second, in particular within a maximum of 0.5 second, in particular fully open within max. 0.2 seconds. A dryer according to any one of claims 3 to 8, wherein the opening mechanism (10) has a second opening (102), which is arranged above the condenser (5), for cleaning the condenser (5), in particular the front surface (51) of the condenser (5) by means of condensate. Dryer according to Claim 9, in which the supply line (9) separates into a first partial line (92) and a second partial line (93), the first partial line (92) conducting condensate water to the first opening (101) and the second partial line (93 ) Condensate water directs to the second opening (102). Dryer according to Claim 9 or 10, in which the condensate water fed to the condenser (5) is collected in the first collecting tank (6) after the condenser (5) has been cleaned. Dryer according to claim 11, having a controller with a cleaning program, designed such that - In a first step, the condensate water is pumped from the first collection tank (6) into the supply line (9), - in a second step, the condenser (5) is cleaned by opening the second opening (102) and the condensate water is conducted into the first collection container (6) after cleaning, - In a third step, the condensate water collected in the first collection tank (6) is pumped back into the supply line (9), - In a fourth step, the evaporator (4) is cleaned by opening the first opening (101). Dryer according to one of the preceding claims, - having a second collecting tank (7), arranged in such a way that the condensate water conducted to the evaporator (4) is collected in the second collecting tank (7) after cleaning the front surface (41) of the evaporator (4), in particular having a pump, designed, to pump the condensate water collected in the second collection tank (7) into the drain, or - Designed in such a way that the condensate water directed to the evaporator (4) is flushed directly into the drain after the front surface (41) of the evaporator (4) has been cleaned. Dryer according to one of the preceding claims, having access (13) for the user to fill water into the first collection container (6), in particular wherein the first collection container (6) has a volume of at least one liter, in particular at least two liters. A dryer according to any one of the preceding claims, comprising a single lint filter (12) with a single filter stage.

Images