WO2013092384A2 - Condensation dryer with a condensate pump, and method for operating a condensation dryer - Google Patents

Abstract

A condensation dryer 1 with a drum 2 for receiving laundry items 2a to be dried is driven by a drive motor 3. A process air channel 10 leads from the interior of the drum 2 into a heat sink constructed as a heat exchanger 6, and a collection container 13 is assigned to the heat exchanger 6 for receiving condensate discharged therefrom. A condensate pump 14 is connected on the suction side to the collection container 13 and is to have a control unit 19 arranged in a pressure line 15, via which control unit the pressure line 15 can be connected on the one hand to a bypass routed into the collection container 13 and on the other hand to a condensate collecting device 16 or a condensate discharge device. The invention also relates to a method for operating a condensation dryer equipped with a condensate pump.

Description

 Condensation dryer with a condensate pump and method for operating a condensation dryer

The invention relates to a condensation dryer with a drum for receiving laundry items to be dried, which is driven by a drive motor, with a leading from the inside of the drum in a heat exchanger formed as a heat sink exhaust duct, wherein the heat sink is associated with a collecting container for this discharged condensate, and with a condensate pump connected to the sump on the suction side. The invention also relates to a method for operating such a condensation dryer.

Household tumble dryers are designed either as exhaust air dryers or as condensation dryers. In the case of the exhaust air dryer, a fan conveys process air, which is heated by means of a heater, into the drum in a so-called open process, where the process air absorbs moisture from the laundry items to be dried and is then conveyed to the outside via an exhaust hose. For the operation of such exhaust air dryer is therefore in the bathroom or basement provide an exhaust pipe to which this exhaust hose can be connected. These preconditions can often only be created with considerable additional effort in residential buildings or owner-occupied or rented apartments, or they are completely ruled out if, for example, the bathroom is located in the inner area of the dwelling or the house. Condensation dryer, to which the present invention relates, are operated in contrast in a so-called closed process, which is also supplied via a heater heated process air from a fan of the drum and there absorbs moisture from the laundry to be dried. However, the moist process air conducted out of the drum passes, after having first passed through a lint filter, into a heat sink in the form of a heat exchanger, in which the process air is cooled. Through the heat sink flow as a cooling medium air or water. In this case, the water condenses from the process air and usually enters a collecting container, which is usually arranged as a trough-like unit below the heat exchanger. Since the moisture is separated from the process air, this can then be fed back via the blower and the heater of the drum. For the cooling of the emerging from the drum Process air and its subsequent heating, a heat pump can be used, which has a serving for the condensation of the moist process air heat exchanger, serving for heating the process air heat exchanger and a compressor.

A condensation dryer of the type described in the preamble of claim 1 is known from DE 20 2005 010 219 U1. The drive motor used in this condensation dryer drives the drum via a main drive shaft and a belt drive extending therefrom, so that the laundry items in the rotating drum are moved and turned in such a way that the heated process air can better attack these laundry items. The drive motor is intended to form a structural unit with the blower serving to convey the process air and the condensate pump associated with a condensate collecting tank. Corresponding rotors of the blower and of the condensate pump are permanently driven by the drive motor during the drying process. A discharge hose emanating from the condensate pump serves to discharge the condensate pumped out of the condensate collector.

It is an object of the present invention to provide for a condensation dryer with a condensate pump, a simple and inexpensive system with which only in case of need for a sufficient amount of condensate in the collecting container amount is conveyed from this in a Kondensatsammeieinrichtung or Kondensatabführeinrichtung. For this purpose, both a condensation dryer and a corresponding method are specified.

This object is achieved on the basis of the preamble of the independent claims 1, 2 and 8, in conjunction with their characterizing features. The optionally dependent on these claims dependent claims are each advantageous embodiments of the invention again, with advantageous developments of the condensation dryer advantageous developments of the method correspond and vice versa, and this even if it is not explicitly stated herein.

According to the characterizing part of independent claim 1, a control device should be arranged in a pressure line connected to the condensation pump. be connected via the pressure line on the one hand with a guided into the collecting container bypass and the other with a Kondensatsammeieinrichtung Kondensatabführeinrichtung, wherein the control device is connected via an air gap with both the collecting container and with the Kondensatsammeieinrichtung Kondensatabführeinrichtung.

During operation of the condensate pump operating conditions may occur in which this sucks air when empty or only partially filled catchment, so that Schlürfgeräusche occur. According to the invention, these problems are eliminated by simple means that the emerging from the pressure line of the condensate pump condensate is optionally returned to a bypass to the collecting container or is derived via a Kondensatsammeieinrichtung or a Kondensatabführeinrichtung. In an operation in which no sufficient amount of condensate accumulated in the collecting container thus promotes the condensate pump condensate this amount in the short circuit through the bypass back into the receptacle, while in a second operating state in which a sufficient amount of condensate accumulated in the collecting container, this condensate from the Pumps off collecting container. The solution assumes that a large volume flow in the pressure line, which is present when the pump draws only condensate, leads to a high delivery speed in the pressure line and thus in the outlet connection. As a result, the condensate emerges from the outlet nozzle as a liquid jet and reaches the second collecting element. If, on the other hand, the condensate is enriched with air, this momentum decreases when the air-water mixture is conveyed, which leads to a reduction in the air gap. As a result of this separate discharge of the medium emerging from the outlet nozzle, an automatic control device is thus created which takes into account the respective operation of the condensate pump.

In contrast, according to the generic DE 20 2005 010 219 U1 an arrangement of a condensate pump is provided, in which this constantly empties the collecting container or can suck from this in its deflated condition only air or an air-water mixture. The previously mentioned noises occur.

As an alternative to the abovementioned solution according to the invention, the condensate pump according to independent claim 2 should not have a separate drive motor. gene, but directly from the drive motor, which is provided for the rotary drive of the drum, are driven. Since this drive motor is almost during the entire drying process in operation, the pump would be constantly in operation even with an empty receptacle so that a pump impeller of the pump would circulate in the filled with air or small amounts of condensate pump housing. In the state in which only small amounts of condensate accumulate together with air in the pump housing of the condensate pump, but considerable noise can occur at the condensate pump. During this operation, additional noises in the form of snore noises occur on the intake manifold of the condensate pump, as it sucks liquid only to a limited extent. In this drive arrangement as well, a control device is provided within a pressure line connected to the condensate pump, via which the condensate is conducted into a bypass leading to the collecting container and / or into a condensate collecting device or condensate discharge device. In a further embodiment of the invention it is provided that the aforementioned control device is designed as a directional control valve, from which serve as a bypass return line to the collecting container and a discharge line to Kondensatsammeieinrichtung or Kondensatabführeinrichtung. This directional control valve can, as further proposed, be designed as a 3/2-way valve, and thus directs the condensate from the pressure line of the condensate pump in the return line and thus back to the collecting container in a first switching position. In a second switching position of the directional valve, however, the condensate is conveyed from the pressure line into the Kondensatsammeieinrichtung or Kondensatabführeinrichtung. The Kondensatsammeieinrichtung is usually designed as removable from a housing of the condensation dryer collecting container in which collect both the condensate and small residual amounts of lint and must be emptied from time to time. Of course, instead of this collecting container, a condensate removal device in the form of a discharge hose connected to a drainage pipe can also be provided.

Furthermore, the invention proposes to actuate the directional control valve in dependence on a level in the collecting container, wherein within the collecting container a transducer is arranged for the determination of its level. It can Of course, the directional control valve also occupy intermediate positions between the two switching positions, so that from the pressure line a subset in the return line and a subset in the Kondensatsammeieinrichtung or Kondensatabführeinrichtung.

As an alternative to the aforementioned embodiment of the control device as a directional control valve, it is further proposed to provide, within the scope of the control device, an air gap via which the pressure line is connected both to the collecting container and to the condensate collecting device or condensate discharge device. In this case, the pressure line may have a horizontally extending outlet nozzle, which are associated with a first associated with the bypass collecting element, which is adjacent to the outlet, and a second further away from the outlet nozzle lying second collecting element. As the first collecting element can directly serve the collecting container or provided with a collecting funnel piece of pipe, which is guided into the collecting container. As a second collecting element while the Kondensatsammeieinrichtung, so preferably a removable collecting container, or a connection of a Kondensatabführeinrichtung should be provided.

Finally, the present invention also relates to a method for operating a condensation dryer with a condensate pump connected to a collecting container, which is selectively driven by a drive motor and promotes the resulting condensate in the collecting container upon reaching a predetermined level in a Kondensatsammeieinrichtung or Kondensatabführeinrichtung.

According to the invention, the air contained in a housing of the condensate pump should initially prevent the ingress of condensate into the housing, while upon reaching a predetermined level in the collecting tank initially the drive of the condensate pump is interrupted and wherein the condensate pump after the ingress of condensate in the housing again is driven. From the design of corresponding condensate pumps is known that they bleed poorly after the ingress of air into the pump housing. This has the consequence that an air bubble in the pump housing remains and prevent the suction and delivery of the condensate. This can be exploited as follows:

At the beginning of a drying process, d. H. with an empty collection container, the impeller of the condensate pump runs in air, the current pump prevents the water rising with continuous operation of the condensation dryer in the collecting container enters the pump housing. The rising water level in the collecting tank is determined by a measuring transducer and the condensate pump drive is briefly stopped so that the counter-pressure generated by the impeller is eliminated and water can rise into the pump housing. After this engine stop, the impeller rotates in the water and can build up a pressure in the pressure line. Another stop of the electric motor driving the condensate pump after the end of a delivery time to be determined ensures again that the water can escape from the pump housing and is replaced by air again, so that the impeller then runs back into air.

The invention is not limited to the specified combination of the features of the independent claim with any of these dependent claims. In addition, there are further possibilities of combining individual features, in particular if they result from the patent claims, the following description of the exemplary embodiments or directly from the drawing. In addition, the reference of the claims to the drawing by the use of reference numerals is not intended to limit the scope of the claims to the illustrated embodiments.

Other features of the invention will become apparent from the following description and from the drawing, in which three embodiments of the invention are shown in simplified form and explained below. Show it

Figure 1 as a schematic representation of the essential components of a

Condensation dryer, as far as these are of importance, 2 shows a first embodiment, according to which a control device is designed as a directional control valve,

FIG. 3 shows a second embodiment, according to which an outlet nozzle emanating from a condensate pump conveys the escaping medium back into the collecting vessel or into a condensate collecting device via an air gap, and a third embodiment in which the condensate pump has passed through a pump housing in the claimed method Air quantity is prevented from conveying the condensate.

In FIG. 1, denoted by 1 is a condensation dryer which has a drum 2. This takes during a drying process in its interior to be dried laundry items 2a, which come from a previous washing and spinning process, so that they are at the beginning of the drying process in a wet state. The drum 2, which is rotatably mounted in a frame of the condensation dryer 1, not shown, is driven by a drive motor 3 via a drive belt 4. Furthermore, the condensation dryer 1 has a heat pump 5, which consists essentially of a first heat exchanger 6 formed as a heat sink, a second heat exchanger 7 and a compressor 8.

Via a coolant circuit 9, the two heat exchangers 6 and 7 and the compressor 8 located between them are connected to each other. Furthermore, the interior of the drum 2 is connected via a process air duct 10 with the two heat exchangers 6 and 7 in connection, wherein within this process air duct 10, a blower 1 1 is arranged. The process air is moved through this process air duct 10, the drum 2, the heat pump 5 and the fan 1 1 in a circuit. The coolant conveyed in the coolant circuit 9 between the two heat exchangers 6 and 7 is a fluorinated hydrocarbon, in particular the product known as R407C, and, after it has absorbed heat from the process air in the first heat exchanger 6 designed as a heat sink, is in one gaseous state, where it is then strongly compressed by the compressor 8. In the second heat 7, this coolant, which is in a gaseous state, then transfers heat to the process air and enters a liquid state. Within the process air duct, a lint filter 12 is arranged on the outlet side of the process air stream emerging from the drum 2.

 5

 Furthermore, the first heat exchanger 6 is associated with a collecting container 13, in which condensate collects, which forms on the cooling surfaces of the first heat exchanger 6 upon impact of the moist and warm process air. From this collecting container 13, the corresponding condensate which accumulates during the drying process is conveyed via a condensate pump 14 and a pressure line 15 emanating therefrom into a condensate collection device designed as a collecting container 16. In this case, the condensate pump 14 may be continuously driven in accordance with the embodiments of Figures 2 and 3 via a drive connection 18, which is illustrated in the schematic representation of Figure 1 by a dashed line 15. In addition, the condensate pump 14 can also be driven by a separate electric motor. The condensate pump 14 sucks the condensate via a suction line 17 from the collecting container 13. Instead, however, the condensate pump 14 may also be arranged directly within the collecting container 13. The condensate pump 14 is usually designed as a centrifugal pump or as a 20-flow pump.

In FIGS. 2 and 3, insofar as the corresponding components have already been explained in the overall view according to FIG. 1, the same reference numerals are used. According to FIG. 2, the pressure line 15 originating from the condensate pump 14 leads to a

25 nem way valve 19, which is connected to a serving as a bypass return line 20 and the other with a drain line 21. The discharge line 21 leads to the collecting container 16. In this case, the directional control valve 19 is in communication with a measuring receiver 22 arranged in the interior of the collecting container 13. This transducer 22, which may be designed, for example, as a float detected

30 the level of existing in the collecting container 13 condensate and adjusted in a corresponding manner, the directional control valve 19th

At a low level of the condensate in the collecting container 13, the directional control valve 19 will be controlled via the transducer 22 such that the condensate in Is essentially fed back via the return line 20 into the collecting container 13. From a certain level of liquid in the collecting container 13, however, the directional control valve 19 is moved to its position in which the condensate pump 14 conveys the condensate substantially via the pressure line 15 and the drain line 21 into the collecting container 16. The control of the liquid flow can be flowing, ie, in a transition region of the positions of the directional control valve 19 and partial streams can be performed both via the return line 20 and via the drain line 21.

According to FIG. 3, an outlet connection 23 adjoins the pressure line 15 and runs horizontally according to FIG. The end of this outlet nozzle 23 is associated with a first bypass element forming the bypass. Furthermore, the outlet port 22 is associated with a second remote collecting element 25 located farther away, which is formed on the collecting container 16 in the present case. Furthermore, it can be seen from FIG. 3 that the medium conveyed by the condensate pump 14 via the pressure line 15 into the outlet pipe 23, depending on its composition, covers the shorter path to the first collecting element 24 or the longer path to the second collecting element 25 over an air gap. In the first case, the pumped by the condensate pump 14 medium primarily of air, which may have a low liquid content, while in the second case, ie in the longer air gap, the medium consists almost completely of condensate. As can further be seen from FIG. 3, the first collecting element 24 may consist of a collecting funnel 26 and a collecting tube 27, the collecting tube 27 opening into the collecting container 16.

Finally, an arrangement is shown in Figure 3, in which the condensate pump 14 is selectively driven by a drive motor 28. In this case, the condensate pump 14 is located within the collecting container 13, so that it at least partially immersed in the condensate or can absorb air even at a lower liquid level in the interior of its housing. Furthermore, a measuring device 29 is arranged in the collecting container 13, which controls the level in the collecting container 13. In this case, the air in the housing of the condensate pump 14 should initially prevent the penetration of liquid into the housing, so that the liquid level in the collecting container 13 increases. When the measuring device 29 registers a certain level, the drive of the condensate pump 14 is briefly switched off, so that the liquid displaces the air from the housing of the stationary condensate pump 14 can. Only then is the condensate pump 14 again driven by the switched-on drive motor 28. After the level in the collecting container 13 has dropped below a certain value, the rotor of the condensate pump 14 again promotes air into the housing.

reference numeral

1 condensation dryer

 2 drum

 2a pieces of laundry

 3 drive motor

 4 drive belts

 5 heat pump

 6 first heat exchanger

 7 second heat exchanger

 8 compressor

 9 coolant circuit

 10 process air duct

 1 1 blower

 12 lint filter

 13 collection container

 14 condensate pump

 15 pressure line

 16 collection containers

 17 suction line

 18 drive connection

 19 control device, directional control valve

 20 return line

 21 drain line

 22 transducers

 23 outlet nozzles

 24 first catch element

 25 second catch element

 26 collection funnels

 27 manifold

 28 drive motor

 29 measuring equipment

Claims

 claims ondensationstrockner (1) with a drum (2) for receiving laundry items to be dried (2a), which is driven by a drive motor (3) with a from the interior of the drum (2) in a heat exchanger (6) formed heat sink leading process air channel ( 10), wherein the heat exchanger (6) is associated with a collecting container (13) for condensate discharged therefrom, and with a condensate pump connected to the collecting vessel (13) on the suction side, characterized in that in a pressure line connected to the condensate pump (14) ( 15) a control device (19) is arranged, via which the pressure line (15) can be connected to a bypass guided into the collecting container (13) and to a condensate collecting device (16) or condensate discharge device, wherein the control device (19) via an air gap both with the collecting container (13) and with the Kondensatsammeieinrichtung (16) or Kondensatabführeinrichtung in Ve commitment. Condensation dryer (1) with a drum (2) for receiving items to be dried (2a), which is driven by a drive motor (3), with a from the interior of the drum (2) in a heat exchanger (6) formed heat sink leading process air channel ( 10), wherein the heat exchanger (6) is associated with a collecting container (13) for condensate discharged therefrom, and with a condensate pump (14) connected to the collecting container (13) on the suction side, which is in continuous drive connection with the drive motor (3), characterized in that in a to the condensate pump (14) connected to the pressure line (15), a control device (19) is arranged, via which the pressure line (15) firstly with a in the collecting container (13) guided bypass and the other with a Kondensatsammeieinrichtung (16) or Kondensatabführeinrichtung is connectable. Condensation dryer according to claim 2, characterized in that the control device (19) is designed as a directional control valve (19) from which serving as a bypass return line (20) to the collecting container (13) and a drain line (21) for Kondensatsammeieinrichtung (16) or Lead the condensate drainage device. Condenser dryer according to claim 3, characterized in that the control device (19) as a 3/2-way valve (19) is formed. Condensation dryer according to claim 2, characterized in that the directional control valve (19) is actuated in dependence on a level in the collecting container (13), wherein within the collecting container (13) a transducer (22) is arranged for its level. Condensation dryer according to claim 2, characterized in that the control device (19) via an air gap with both the collecting container (13) and with the Kondensatsammeieinrichtung (16) or Kondensatabführeinrichtung is in communication. Condenser dryer according to claim 6, characterized in that the pressure line (15) has a horizontally extending outlet port (23) to which a first bypass element connected to the collecting element (24), which is the outlet port (23) adjacent, and a second farther from the Outlet (23) lying second catch element (25) are assigned. Method for operating a condensation dryer (1) with a condensate pump (14) connected to a collecting container (13) which can be driven selectively by a drive motor (28) and the condensate accumulating in the collecting container (13) reaches a condensate collecting device when a predetermined filling level is reached ( 16) or Kondensatabführeinrichtung promotes, characterized in that in a housing of the condensate pump (14) located air initially prevents the ingress of condensate into the housing, that upon reaching a predetermined level in the collecting container (13), first the drive of the condensate pump (14) is interrupted and that after the ingress of condensate into the housing, the condensate pump (14) is driven again.