EP2372014A1 - Laundry drying device with a chamber pump and method for pumping condensate - Google Patents

Abstract

The pump (2) has a chamber (3) filled with liquid i.e. condensate water (K), and comprising an inlet valve (8) and an exhaust valve (22). An air pump (5) is connected with the chamber, where pressure and suction are alternatively acted upon the chamber such that the inlet and exhaust valves are opened and closed during suction, and the exhaust and inlet valves are opened and closed during application of pressure. A level sensor senses levels (P1, P2) of the liquid in the chamber, and a control unit (S) is coupled with the sensor. An independent claim is also included for a method for pumping liquid in a household appliance.

Description

The invention relates to a laundry drying apparatus with a pump and a method for pumping condensate in the laundry dryer.

DE 10 2008 032 800 A1 describes a device for cleaning a component, in particular an evaporator of a condenser device, wherein the device is equipped with a arranged within a process air cycle of a washing or tumble dryer to be cleaned component, in particular an evaporator of a condenser device, as well as with a condensate water pan, in which Condensate water resulting from the drying of wet laundry can be trapped, passed from this to a rinsing container provided above the vaporizer and emanated from an outlet opening to the component to be cleaned, wherein the rinsing container is a closure member for selectively opening and closing the outlet opening and an actuator for actuating the closure part, wherein the closure part has a sealing head for closing the outlet opening, the verb verbun with a rotatably mounted on the first container lever arm is unden. The condensate water is pumped up from the condensate water tank by means of a typically rotating pump directly into the rinsing tank. However, it is disadvantageous that in the condensate water long fluff or hair can block the pump block. The same applies to lye pumps in washing machines.

It is the object of the present invention to at least partially alleviate or even avoid the disadvantages of the prior art and, in particular, to provide an easily implementable possibility for conveying liquid, in particular condensate water, which is insensitive to foreign bodies present in the liquid, in particular lint and hair , is.

This object is achieved according to the features of the independent claims. Preferred embodiments are in particular the dependent claims, but also the following description, removable.

The object is achieved by means of a chamber pump, comprising a liquid-fillable chamber (which can also be called 'pumping chamber') and a pneumatically connected to the chamber air pump, the chamber having an inlet valve and an outlet valve for the liquid and the chamber by means of the air pump can be acted upon alternately or alternatively with pressure (overpressure) and suction (negative pressure), so that when the intake valve opens, the inlet valve closes and the pressure valve opens and the inlet valve closes.

Thereby, the liquid in the chamber can be pushed out by the overpressure generated by the air pump through the outlet valve, without the liquid itself has to flow through a pump and consequently can not clog or settle. Fluff or long fibers and hair can flow unhindered through the valves. In addition, the chamber can be arranged arbitrarily in the household appliance, which allows a compact design of the household appliance. In addition, the chamber pump has a high and continuous pumping power.

The outlet valve for the liquid may be, e.g. be guided via a riser, to a target system or be connected to it. The target system is not limited and may be e.g. include each unit of the household appliance, which requires a liquid supply.

The air pump is mechanically operated and can also be referred to as a compressor.

It is a preferred embodiment that the chamber pump has at least one fill level sensor for sensing a fill level of the liquid in the chamber and at least one control unit coupled to the at least one fill level sensor, wherein the control unit is configured with or after reaching an upper limit value of To switch the pressure of the chamber from suction to pressure and to switch with or after reaching a lower limit of the level of pressure to suction.

Thereby, the level of the liquid in the chamber between the lower limit and the upper limit can be maintained and so the maximum one-step in a step Pump volume can be determined. In addition, overflow of the chamber is prevented.

In other words, with or after reaching the upper limit of the level, compressed air is pumped into the chamber, thereby opening the outlet valve and closing the inlet valve, and pushing out or discharging the liquid in the chamber through the outlet valve. As a result, the level in the chamber decreases until the lower limit is reached or fallen below. Then air is sucked out of the chamber and consequently generates a negative pressure. Due to the resulting negative pressure in the suction chamber, the inlet valve opens and the outlet valve closes. As a result, new fluid flows through the inlet valve into the chamber, which again increases the level until the upper limit is reached again or exceeded.

Generally, the delivery process can be carried out once, depending on the amount to be conveyed, in whole or in part, as well as individually repeated periodically or in stages.

It is a further preferred embodiment that the air pump is a reversible air pump and the control unit is designed to reverse the air pump. Thus, it is possible to dispense with a changeover valve for switching over a pneumatic connection of the chamber between different connections of the air pump.

It is still a preferred embodiment that between the air pump and the chamber, a switching valve is arranged pneumatically, the switching valve is adapted to switch the chamber pneumatically between a suction inlet and a pressure outlet of the air pump and the control unit is configured to switch the switching valve. As a result, the air pump can be made simpler.

It is also a preferred embodiment that the inlet valve and the outlet valve are each configured as a check valve. For this purpose, the inlet valve and the outlet valve, for example, each have a covering element for an opening, which covers the edge of the opening areally. The flat sealing contact thus produced is particularly advantageous in contrast to a conventional line-like sealing contact for conveying contaminated with hair and long fibers liquids, since the hair and long Fibers with a closed valve can not or only very difficult to pass through the flat sealing contact. The large sealing surface also provides sufficient reserve to cope with heavy soiling. A valve may also be considered as a unit of the cover member and the associated opening.

It is also a preferred embodiment that the respective cover member is bent up in an open position of the associated opening and / or is pivoted away or can be. The cover can thus cover the edge of the associated opening in a simple manner surface. It is a development that the cover is plate-shaped. The cover may in particular consist of an elastic plastic material. The cover may be fixed or pivotally connected to the chamber.

It is also a preferred embodiment that the inlet valve (with the associated inlet opening) is arranged in a bottom of the chamber. The outlet valve may in particular be incorporated in a side wall of the chamber, in particular in a lower half of the side wall.

It is still a preferred embodiment that between the air pump and the chamber, a controllable valve is present and between the air pump and the valve, a cavity is present. This results in the advantage that in the case of deterioration of the performance of the chamber pump due to contamination (eg worsen the tightness of the valves) and / or blockages or generally or regularly the chamber are ruptured flush for flushing the clogged and / or dirty areas can. The deterioration of the performance of the chamber pump can be detected, for example, by a deviation from typical pumping times. For this purpose, the accumulator with closed valve with compressed air (to a lesser extent with negative pressure) are applied and then the valve can be opened suddenly. Thus, a large effect on the hydraulic system or the chamber is achieved, which leads to an increased flow or even turbulence of the liquid. The associated additional effort is very low and controllable by the controller, especially in the variant with the non-reversible pump.

It is still a preferred embodiment that the chamber pump is intended for use in a household appliance. In particular, foreign matter (e.g., in condensate water, caustic or rinse water, etc.) that can clog a conventional fluid pump is typically accumulated in this area. Therefore, an application of the chamber pump is particularly advantageous here. However, the chamber pump is not limited to large household electrical appliances or household appliances per se. Rather, the range of applications of the chamber pump can extend to the entire field of pumps with comparable performance data.

The object is also achieved by a household appliance, wherein the household appliance has at least one chamber pump according to one of the preceding claims. The household appliance can basically be any water-bearing household appliance.

It is a preferred embodiment that the household appliance is a laundry drying device and the chamber pump is a condensate water pump. The chamber pump is particularly advantageous here, since the condensate water typically has hair and long fibers from the laundry to be dried. The target system may e.g. be a condensate collection container or include such. The condensate collector may e.g. a rinse tank for rinsing a device component such as a heat exchanger (e.g., an evaporator in the case of a heat pump dryer) and / or a lint filter. The condensate collection container may additionally or alternatively be designed to be removable from the laundry drying apparatus for emptying the liquid. However, the target system can also be the unit (s) to be cleaned as such, possibly with the interposition of a filter.

It is still a preferred embodiment that the household appliance is a washing device (washing machine, washer-dryer, etc.) or a flushing device (dishwasher, etc.) and the chamber pump is a drain pump. Also in the liquor may be foreign particles that could clog a conventional hydraulic pump.

It is a preferred development that the chamber pump has a trough-shaped housing part and a lid which can be placed on it in a sealing manner. This makes the chamber pump easy to assemble. It is a preferred for simple installation special training that outside the chamber, in particular on the lid, the Air pump, if available, the changeover valve and / or an outlet opening to the target system (container, drain, heat exchanger, sieve, etc.) are attached or arranged.

• (Pneumatisches) Erzeugen eines Unterdrucks in einer Kammer (z.B. mittels einer Luftpumpe), so dass durch ein Einlassventil Flüssigkeit in die Kammer fließt;
• Umschalten von dem Erzeugen des Unterdrucks in ein (pneumatisches) Erzeugen eines Überdrucks in der Kammer, wenn ein Pegel der Flüssigkeit einen oberen Grenzwert erreicht oder überschreitet, so dass das Einlassventil schließt und die in der Kammer befindliche Flüssigkeit durch ein Auslassventil fließt;
• Umschalten von dem Erzeugen des Überdrucks in ein erneutes Erzeugen eines Unterdrucks in der Kammer, wenn ein Pegel der Flüssigkeit einen unteren Grenzwert erreicht oder unterschreitet, so dass das Auslassventil schließt.

The object is also achieved by a method for pumping liquid in a domestic appliance, the method having at least the following steps:

• (Pneumatic) generating a negative pressure in a chamber (eg by means of an air pump) so that liquid flows into the chamber through an inlet valve;
• Switching from generating the negative pressure to (pneumatic) generating an overpressure in the chamber when a level of the liquid reaches or exceeds an upper limit such that the inlet valve closes and the liquid in the chamber flows through an outlet valve;
• Switching from generating the overpressure to repressurizing the chamber when a level of the liquid reaches or falls below a lower limit such that the exhaust valve closes.

Fig.1

zeigt eine Funktionsskizze eines Wäschetrockners mit zur Beschreibung der Kammerpumpe ausgewählten Elementen;

Fig.2

zeigt in Schrägansicht eine mögliche Ausführung der Kammerpumpe.

In the following figures, the invention will be described schematically with reference to a preferred embodiment schematically. In this case, the same or equivalent elements may be provided with the same reference numerals for clarity.

Fig.1

shows a functional diagram of a clothes dryer with elements selected for the description of the chamber pump;

Fig.2

shows an oblique view of a possible embodiment of the chamber pump.

Fig.1 Sketches selected components of a tumble dryer 1. The tumble dryer 1 has a chamber pump 2 with a chamber 3, serving as an air direction changeover switch 4 and an air pump 5. The chamber 3 is in a condensate water reservoir 6, which is filled with condensate water K. The chamber 3 has in its bottom an inlet opening 7, which opens into the condensate water reservoir 6 and which is covered by a non-return valve 8 serving as an inlet valve. The check valve 8 allows the condensate water K to flow into the chamber 3 and prevents it from flowing back into the condensate water reservoir 6. The chamber 3 has an outlet opening 9 in a side wall, from which a riser 10 leads into a washing container 11. In the riser 10 is another, serving as an outlet valve check valve 22 is present, which is a flow of condensate water K allowed out of the chamber 3 in the washing container 11 and prevents backflow into the chamber 3. The chamber pump 2 thus serves for pumping condensate water K from the condensate water reservoir 6 into the washing container 11. The chamber pump 2 can be arranged, for example, at a bottom of the tumble dryer 1, the insertion into the condensate water reservoir 6 allowing a particularly compact design.

By means of the switching valve 4, the chamber 3 can alternately to a suction inlet 12 and a suction side of the air pump 5 (as shown) and be connected to a pressure side or a pressure outlet 13 of the air pump 5. The respective other side or the respective other connection 13, 12 is connected via the switching valve 4 with a ventilation opening 14.

In the illustrated first position of the switching valve 4, in which the suction inlet 12 is connected to the chamber (suction position), the air pump 5 sucks air from the chamber 3 and thus generates there a negative pressure. The negative pressure causes the check valve 8 opens and condensate water K can flow from the condensate water reservoir 6 in the chamber 3 and is sucked. The check valve 22 is held closed by the negative pressure. As soon as an upper limit value P1 of a level of the condensate water K (the condensate water level) is reached, as indicated by the upper arrow, the changeover valve 4 is switched over and now connects the pressure outlet 13 with the chamber 3 and the suction connection 12 with the ventilation opening 14.

Now, an overpressure is generated in the chamber 3, which pushes the check valve 8 and pushes condensation water K through the riser 10 and through the check valve 22 upwards. So the condensate water K can be promoted in the washing tank 11. Once so much of the condensate water K has been promoted from the chamber 3, that the level of condensate K reaches a lower limit P2, as indicated by the lower arrow, the switching valve 4 is switched again and re-filling the chamber 3, this again with the Saugeingang 12. The switching valve 4 is thus in the first position, a connection between the suction inlet 12 of the air pump 5 and the chamber 3 free and in the second position, a connection between the pressure outlet 13 of the air pump 5 and the chamber. 3

One way to determine the achievement of the upper limit P1 and the lower limit P2 is to provide at least one corresponding level sensor 21 (off Fig.2 ) on or in the chamber 3 and to couple with a control unit S, as indicated by the corresponding dashed lines. The control unit S can evaluate the sensor data supplied by the at least one sensor and can switch over or switch over when reaching or exceeding or falling below the respective limit value P1, P2, the switching valve 4 (indicated by further corresponding dashed lines).

Fig.2 shows an oblique view of a possible embodiment of the chamber pump 2. The chamber pump 2 has a cavity 3 designed as a chamber 3, which has feet 15 on its underside. By the feet 15 it is achieved that the inlet opening 7 has a sufficient distance from the bottom 16 of the condensate water reservoir 6 and so a flow of the liquid K through the bottom inlet opening 7 is not hindered. The chamber-side check valve 8 (inlet-side suction valve) is formed by means of a chamber side selectively on the inlet opening 7 sealingly placed and for example liftable by a bend and / or pivoting plastic plate.

The chamber 3 is embodied here in two parts, in that a partition wall 17 is arranged in the chamber 3, which subdivides the chamber 3 into a first chamber area 3a with the inlet opening 7 and the check valve 8 and into a second chamber area 3b with a now upper-side outlet opening 9. The first chamber region 3a can also be considered as the chamber in the narrower sense. The first chamber area 3a has a volume of 100 ml to 500 ml. The partition 17 has in a lower region on a passage opening 18, which is also formed by a check valve 19 in the form of a liftable by bending and / or pivoting plastic plate. The check valve 19 is disposed on the side of the second chamber portion 3b and allows flow from the first chamber portion 3a into the second chamber portion 3b, but prevents an opposite return flow (pressure valve). The check valve 19 thus corresponds functionally to the check valve 22 Fig.1 , Since the check valves 8, 19 are plate-shaped, results in a flat sealing contact, which is particularly advantageous for the conveyance of contaminated with hair and lint fluids. The large sealing surface also provides sufficient reserve to handle even heavy soiling. A certain leakage through stuck in the check valves 8, 19 soiling can be absorbed by a reserve power of the air pump 5. For the problem-free conveying of liquids contaminated with hair and lint, the inlet opening 7 and the passage opening 18 each additionally have a large passage cross-section.

The switching valve 4 and the air pump 5 are attached to a top 20 of the chamber 3 and connected by respective hoses. The switching valve 4 is further connected via an air line 29 designed as a tube with the chamber 3, more precisely, the first chamber portion 3a. Alternatively, an integrated embodiment can be used, in which the cover of the air pump 5 and the switching valve 4, possibly also the air pump 5 itself, are directly connected to each other and / or made of one piece. This can save at least one hose connection. In particular, all hose connections can be saved, which can reduce installation costs and a susceptibility to errors.

A level sensor or level sensor 21 is arranged in or on the first chamber area 3a in order to detect a liquid level or fill level at the limit values P1 or P2. The level sensor 21 is off with the control unit S. Fig.1 coupled. The level sensor 21 may be formed as a single level sensor, in particular with two Sensierstellungen at P1 or P2, as well as a group of several level sensors. The level sensor 21 may include, for example, electrodes at P1 and P2, include a float, provide a time estimate of the level (virtual sensor), by level measurements outside the chamber 3 or by a motor current monitoring of the air pump to draw a conclusion on the level, etc. The upper liquid level P1 in the first chamber portion 3a is preferably just below the suction of the air pump 5. By switching the air pump 5 upon reaching the upper liquid level P1 to a pressure operation in addition to ensuring the function of the entire chamber pump 2 and a suction of the liquid through the air pump. 5 (The so-called "water hammer"), which is associated with a possible damage to the air pump 5 can be prevented.

The chamber 3 can be assembled for easy assembly of a trough-shaped housing part 23 and a cover 24. The trough-shaped housing part 23 comprises the bottom-side inlet opening 7. The partition 17 can be inserted into the trough-shaped housing part 23 or formed integrally therewith. The switching valve 4 and the air pump 5 may be attached to the lid 24 for ease of manufacture and maintenance.

In operation, in the first switching position of the switching valve 4 by means of the air pump 5, air is sucked out of the first chamber region 3a through the air line 29, thus generating a negative pressure there. By the negative pressure, the check valve 8 is bent up or pivoted upwardly, while the check valve 19 is sealingly sucked onto the passage opening 18. As a result, the first chamber area 3a fills until the liquid K reaches the upper level sensor 21. Upon reaching the upper level sensor 21, this outputs a corresponding sensor signal to the control unit S. Fig.1 out. The control unit S then switches the changeover valve to the second position, and compressed air is now blown through the air line 29 into the first chamber region 3a, which is consequently pressurized. The overpressure presses the check valve 8 on the inlet port 7 and further causes liquid K, the check valve 19 is pressed and conveyed into the second chamber portion 3b. From the second chamber area 3b, the liquid is further conveyed out of the chamber 3 through the upper-side outlet opening 9. The second switching position is maintained until the liquid level in the first chamber region 3a falls below the lower limit value P2, whereupon the control device S brings the changeover valve for refilling the chamber 3 from the liquid reservoir 6 back into the first switching position.

The chamber pump 2 is insensitive to long fibers, fluff or hair (hair-like). It can be used particularly advantageously as a condensate water pump in laundry drying devices (in particular equipped with a heat pump devices) and as a drain pump for pumping and pumping in washing and flushing equipment. The chamber pump 2 is also suitable as a metering pump in particular for portionwise but also continuously variable metering or similar applications. The chamber pump 2 has only relatively coarse valves 8, 19 for this purpose.

Depending on the quantity to be delivered, the pumping process can be carried out once, completely or partially, and individually repeated periodically or in stages. The liquid is conveyed in portions which correspond at most to the chamber volume between the two limit values or water levels P1 and P2. At lower levels to be delivered (e.g., residual amounts) or otherwise, hysteresis due to sensing may also be circumvented.

The chamber pump 2 pumps the liquid or the medium in relatively large portions, and analogously to conventional pumps such as a reciprocating pump or a diaphragm pump with a very large chamber volume. During a stroke of the chamber pump 2, relatively long-lasting flows result without interruptions, which significantly reduces a tendency of the foreign bodies in the liquid to settle. In the case of the two classic types of pumps mentioned, to achieve this pumping volume or the large stroke, a complex gearbox with a high gear ratio would be necessary. The accumulation of compressed air or suction air replaced in the chamber pump 2, the mechanical transmission. The chamber volume of the air pump 5 can thus be very small, and the air pump 5 can run at high speed and thus very good efficiency without a transmission gear. The pumping action in the hydraulic part is realized by the action of the cumulative pressure conditions in the chamber 3 or in the first chamber area 3a.

Of course, the present invention is not limited to the preferred embodiment shown.

Thus, instead of the combination of a (in particular non-reversible) air pump 5 and the switching valve 4, a reversible air pump can be used.

In addition, between the air pump and the existing switching valve (or an additional valve in a reversible pump), a cavity may be present as an accumulator. In the case of a deterioration in the performance of the chamber pump due to contamination and / or blockages (which can be determined, for example, by a deviation from typical pumping times) or also generally or in rotation, the pressure accumulator can be replaced with compressed air (typically to a lesser extent) instead of the chamber also with negative pressure) and through the valve abruptly with great effect on the hydraulic system or the chamber for flushing the clogged / polluted areas apply. The associated additional effort is very low and controllable by the controller especially in the variant with non-reversible pump.

Also, containers or cavities (conduits and hoses, tanks, storage tanks, etc.) given by the target system may be connected to the individual components (inlet valve, outlet valve, air pump, air direction switch) such that the overall system is an integrated pump. The incorporation of existing structures may also allow the saving of other components, such as when the portion size of the chamber pump corresponds to the total amount to be delivered at one time and the source or target container is used as the chamber.

LIST OF REFERENCE NUMBERS

1

clothes dryer

2

chamber pump

3

chamber

3a

first chamber area

3b

second chamber area

4

switching valve

5

air pump

6

Condensate reservoir

7

inlet port

8th

check valve

9

outlet

10

riser

11

rinse tank

12

suction inlet

13

pressure outlet

14

vent

15

stand

16

ground

17

partition wall

18

Port

19

check valve

20

top

21

level sensor

22

check valve

23

housing part

24

cover

29

air line

K

condensate water

P1

upper limit of condensate water level

P2

lower limit of condensate water level

S

control unit

Claims (10)

Clothes drying apparatus (1), comprising a condensate water pump in the form of a chamber pump (2), wherein the chamber pump (2) has a condensate (K) fillable chamber (3, 3a) and connected to the chamber (3, 3a) air pump (5) and wherein the chamber (3) - An inlet valve (8) and an outlet valve (22) for the condensate (K) and has - By means of the air pump (5) can be acted upon alternately with pressure and suction, so that when suction the inlet valve (8) opens and the exhaust valve (22) closes and opens the outlet valve (22) and closes the inlet valve (8). Laundry drying apparatus (1) according to claim 1, wherein the chamber pump (2) at least one level sensor (21) for sensing a level (P1, P2) of the condensate (K) in the chamber (3) and at least one with the at least one level sensor (21 ) coupled control unit (S), wherein the control unit (S) is adapted to switch with or after reaching an upper limit (P1) of the level, the admission of the chamber (3) from suction to pressure and with or after reaching a lower limit (P2) to change the level from pressure to suction. Laundry drying apparatus (1) according to claim 2, wherein the air pump (5) is a reversible air pump (5) and the control unit (S) is adapted to reverse the air pump (5). Laundry drying apparatus (1) according to claim 2, wherein - between the air pump (5) and the chamber (3) a switching valve (4) is arranged pneumatically, - The switching valve (4) is adapted to switch the chamber (3) pneumatically between a suction inlet (12) and a pressure outlet (13) of the air pump (5) and - The control unit (S) is adapted to switch the switching valve (4). Laundry drying apparatus (1) according to one of the preceding claims, wherein the inlet valve (8) and the outlet valve (22) each have a cover element (8, 19) for an opening (7, 18) which surrounds the edge of the opening (7, 18). flat cover and wherein the respective cover member (8, 19) is pivoted in an open position of the associated opening (7) bent upwards. Laundry drying apparatus (1) according to claim 5, wherein the cover member (8, 19) is fixedly connected to the chamber (3, 3a) and consists of a resilient plastic material. Laundry drying apparatus (1) according to one of the preceding claims, wherein between the air pump (5) and the chamber (3) a controllable valve is present and between the air pump (5) and the valve (4) has a cavity. Laundry drying apparatus (1) according to one of the preceding claims, wherein the outlet valve (22) is connected to a rinsing container for rinsing a device component of the laundry drying apparatus (1). Laundry drying apparatus (1) according to any one of the preceding claims, wherein the chamber pump (2) has a trough-shaped housing part (23) and a lid (24) which can be placed on it in a sealing manner. A method of pumping condensate (K) in a clothes drying apparatus (1), the method comprising at least the following steps: - generating a negative pressure in a chamber (3), so that through an inlet valve (8) condensate (K) flows into the chamber (3); Switching from generating the negative pressure to generating an overpressure in the chamber (3) when a level (P1) of the condensate (K) reaches or exceeds an upper limit value (P1), so that the inlet valve (8) closes and the in the chamber (3) located condensate (K) through an outlet valve (22) flows; Switching from generating the overpressure to re-generating a negative pressure in the chamber (3) when the level of the condensate (K) reaches or falls below a lower limit value (P2) so that the outlet valve (22) closes.

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