EP3026167A1 - Laundry drying device and method of operating a laundry drying device - Google Patents

Abstract

A laundry drying device (1) has a laundry drying space (2) which is connected to a process air duct (5) to a process air circuit (2, 5), wherein in the process air duct (5) a capacitor (7), a heater (9) and a process air blower (6) for circulating the process air (P) in the process air circuit (2, 5) are arranged, further comprising a heat pump (7, 9-12) with a drive (10), serving as the first heat exchanger and condenser a second heat exchanger serving as the heater (9), further comprising a closure device (15) for opening and closing a first air passage opening (14) of the process air circuit and having a shut-off device for opening and blocking the process air duct, wherein the heater (9) and the process air blower (6) are arranged between the first air passage opening (14) and the shut-off device and thus steer the closure device and the shut-off device Rbar are that at the same time the closure device releases the first air passage opening (14) and the shut-off device shuts off the process air duct (5).

Description

The invention relates to a laundry drying apparatus, comprising a laundry drying room with a process air inlet opening and a process air outlet opening, which openings are connected to a process air circuit by means of a process air duct, wherein in the process air duct, a condenser for cooling process air exiting from the laundry drying room, a heater for Reheating previously cooled process air and a process air blower for circulating the process air are arranged in the process air circuit, further comprising a heat pump with a drive, serving as the first heat exchanger and a second heat exchanger serving as the condenser, and further comprising a controllable closure device for selectively Opening and closing a first air passage opening of the process air circuit. The invention is particularly advantageously applicable to household laundry drying appliances.

In heat pump dryers with a compressor heat pump, the heat pump heats up frequently over a period of drying. To prevent the compressor from overheating, some heat pump dryers turn on an additional fan when a limit temperature is reached, which sucks ambient air into the heat pump drier from the outside and directs it to the compressor and pipework of the heat pump. The ambient air cools the compressor and dissipates heat from the heat pump. The auxiliary fan is usually located on a front side of the device. There are versions in which a separate heat exchanger is arranged behind the additional fan in order to increase the heat removal from the heat pump's refrigeration cycle. However, this design is expensive. The additional fan also produces clearly audible sounds.

DE 40 23 000 C2 discloses a clothes dryer with a process air for heating, which is guided by a motor driven blower in a closed process air duct through a laundry drying room, and for precipitating the entrained in the process air from the laundry drying room heat pump circuit from condenser, evaporator, compressor and throttle and further With an adjustable exhaust air opening in the process air duct between the condenser and the laundry drying space, wherein between the evaporator and the condenser in the process air duct an air inlet opening is arranged, which is closable with a controllable closure device.

DE 10 2008 043 176 A1 relates to a dryer with a drying chamber for objects to be dried, a supply air duct, a process air duct, an exhaust duct and a heat pump with a heat sink and a heat source, wherein the supply air duct and the exhaust duct by means of a mechanism via a recirculating air duct for adjusting a proportion of recirculation and exhaust air can be interconnected in the dryer. Also disclosed are a method of operating this dryer and a method of controlling the temperature and / or humidity of an air in a room using this dryer.

It is the object of the present invention to overcome the disadvantages of the prior art, at least in part, and in particular to provide a possibility for improved cooling of a heat pump in a laundry drying apparatus, in particular in a recirculating tumble dryer.

This object is achieved according to the features of the independent claims. Preferred embodiments are in particular the dependent claims.

The object is achieved by a laundry drying apparatus, comprising a laundry drying room with a process air inlet opening and a process air outlet opening, which openings are connected to a process air circuit by means of a process air duct, wherein in the process air duct, a condenser for cooling process air exiting from the laundry drying room, a Heater for warming up previously cooled process air and a process air blower for circulating the process air are arranged in the process air circuit, further comprising a heat pump with a drive, serving as the first heat exchanger and a second heat exchanger serving as the heater, further comprising a controllable closure device for optionally opening and closing a first air passage opening of the process air circuit, and having a controllable shut-off device for selectively opening and closing the Process air channel wherein the heater and the process air blower are arranged in the process air duct between the first air passage opening and the shut-off device and the closure device and the shut-off device are controllable so that at the same time the closure device at least partially releases the first air passage opening and the shut-off device at least partially shuts off the process air passage.

Among other things, this laundry drying apparatus has the advantage that, during a cooling process with a blocked process air duct, no air flows through the laundry drying space and thus no or only insubstantially moisture is removed from the apparatus. As a result, the condensation efficiency is not lowered. In addition, this clothes dryer is easy and inexpensive to produce. The ambient air flowing into the process air duct through the first air passage opening may be sucked in from inside the clothes dryer or from outside the laundry dryer.

Another advantage is that it is possible to dispense with an additional fan and also with an additional heat exchanger. In particular, even with suction of the ambient air from the interior of the laundry drying device can account for a ventilation opening in a particular front housing wall. This range is then subject to less restrictions and is e.g. to the designerischen design available. For example, the device can obtain a smooth front by eliminating the front ventilation opening. The elimination of the front ventilation opening results in the further advantage that a sound radiation of the compressor forward is significantly reduced.

The cooling of the heat pump is also much faster than by an additional fan. So a drying time can be shortened. By cooling down, the process conditions shift into a more favorable for the efficiency of the heat pump area, so that a total energy consumption can be reduced.

Under an air passage opening may be understood in particular an opening through which air can flow or flow into the process air duct. The air passage opening may be arranged in a wall of the process air channel, for example in the form of a hole.

The closure or shut-off of the process air duct by the shut-off device, however, affects a change in a flow cross-section of the process air duct.

The clothes dryer is a circulating air dryer in whose nominal operation, in which process air flows through the laundry drying room, the laundry drying room and the process air duct form a closed circulating process air cycle. In the cooling mode, in which the first air passage opening is at least partially open and the process air duct is at least partially shut off, exclusively or additionally an open exhaust air duct is present, which conducts the ambient air via the heater or the second heat exchanger.

The laundry drying apparatus is particularly a household laundry drying apparatus. The clothes dryer may be a stand-alone tumble dryer or a combined laundry / drying machine or washer-dryer.

The laundry drying room may be a laundry drum, in particular a rotatable laundry drum. The laundry drum may be rotatable about a horizontal axis of rotation. The process air inlet opening and the process air outlet opening may then be arranged on end faces of the laundry drum. For example, the process air inlet opening may be located on a rear end face of the laundry drum and the process air outlet opening may be located on a front end face of the laundry drum.

At the first heat exchanger serving as a condenser, warm-moist process air flowing out of the laundry drum cools and is condensed. The condensate thus obtained drips e.g. into a condensate tray and may be pumped into a drain or rinse tank.

The serving as a heater second heat exchanger is located downstream of or behind the condenser or behind the first heat exchanger with respect to the flow direction of the process air and heats the condensed process air again before it flows back into the laundry drum.

The process air blower may in particular be arranged between the heater and the laundry drum and thus also with respect to the flow direction of the process air downstream of the heater. The process air blower may e.g. be an axial fan or a radial fan.

The heat pump may be a compressor heat pump having a compressor as the drive, an evaporator as the first heat exchanger, and a condenser as the second heat exchanger. It also has a throttle in a basically known way. These components are basically known components of a circuit in which working or refrigerant circulates. The heat pump may therefore also be referred to as a "refrigeration cycle".

Alternatively, the heat pump may be configured as a Stirling heat pump or as a Vuilleumier heat pump.

The controllable closure device and the controllable shut-off device are in particular electrically controllable. They may be controllable by means of a common actuator (e.g., a piezoelectric actuator or an electric motor) or coupled to a respective actuator.

Due to the fact that the heating and the process air blower are arranged in the process air duct between the first air passage opening and the shut-off device, a significant volume flow of the ambient air flows through these two components when the process air duct is closed or shut off.

It is a further development that only the heating and the process air blower are arranged in the process air duct between the first air passage opening and the shut-off device. Thus, when the first air passage opening and the process air duct are closed, a significant volumetric flow of the ambient air flows through these two components of the process air duct, but not through the laundry drying room or through the first heat exchanger or condenser. As a result, a particularly high efficiency can be maintained.

Depending on the heat pump / refrigeration cycle and device configuration, the process air has a typical process air temperature of typically between 35 ° C and 60 ° C in nominal operation when entering the second heat exchanger or heating (but is not limited thereto). At higher ambient temperatures and in a final phase of drying, in which a moisture of the effluent from the process air outlet opening of the laundry drying device process air decreases, the process air temperature rises. Sucked ambient air is at about 15 ° C to 30 ° C well below the process air temperature. The temperature gradient between a circulating in the heat pump refrigerant and the ambient air is thus significantly greater than between the refrigerant of the heat pump and the process air. This has a favorable effect on the heat transfer.

If the temperatures of the heat pump increase, it is possible to switch over from nominal operation to cooling operation. For this purpose, in a variant, the first air passage opening is at least partially opened and the drive is kept in operation. The process air circulation is interrupted and no or only a very small volume flow flows through the evaporator. At this point, therefore, there is no further heat input into the heat pump, but only through the work of the drive. Thus, a total cooling of the heat pump takes place, so the heat dissipation through the ambient air must be greater than the heat generated by the work of the drive. The larger this difference, the faster the cooling of the heat pump can take place and the lower the total energy loss in the cooling operation.

It is a development that a volume flow of the ambient air in cooling operation is between about 10% to about 50% of the volume flow of the process air in nominal operation.

It is still a development that the first air passage opening is opened only for a relatively short time, in particular between about 5 s and about 100 s, until a sufficient cooling has been achieved.

The switching between the rated operation and the cooling operation may be triggered by a temperature measurement at a suitable location on the heat pump. The cooling mode may either expire for a predetermined period of time or be terminated again via a temperature measurement.

It is a further development that the closure device and the shut-off device can be controlled independently of one another, which permits a particularly varied air guidance in the process air channel, both in nominal operation and in cooling operation. Alternatively, the closure device and the shut-off device may not be independently controllable, but e.g. just matched.

It is a further development that in a first setting state the closure device completely closes the first air passage opening and the shut-off device completely releases the process air channel and in a second setting state the closure device releases the first air passage opening and the shut-off device completely shuts off the process air channel. As a result, an admixture of ambient air to the process air flow in nominal operation and an admixture of process air in cooling operation can be avoided. The first setting state may also be referred to as a first end position, nominal position or circulating air position, while the second setting state may also be referred to as a second end position, cooling position or exhaust air position.

It is basically possible to operate the cooling operation without a further air passage opening located between the first air passage opening and the shut-off device. In this case, air may leak out of the process air duct due to leakage.

It is an advantageous for achieving a high volume flow of ambient air as well as for precise adjustment of the volume flow that the shut-off alternately at least partially releases or shuts off the process air duct and a second air passage opening of the process air circuit is at least partially closed or released, the heater and the process air blower are arranged in the process air channel between the first air passage opening and the second air passage opening. Thus, if the shut-off device releases the process air duct at least partially, the second air passage opening of the process air circuit is at least partially closed, and vice versa. The ambient air flows in cooling mode so first through the first air passage opening in the process air duct and exits at the second air passage opening again, or vice versa. The air passage opening, through which ambient air flows into the process air duct, may Also referred to as Zuluftöffnung. The air passage opening through which air exits the process air duct may also be referred to as the exhaust air opening. The direction of the air flow is predetermined by the process air blower and may always have the same direction through the process air blower or experience a change of direction.

The second air passage opening may optionally be opened and closed by a further closure device. It is a development that the two closure devices and the shut-off device can be controlled independently of each other, which allows a particularly varied air flow in the process air duct, both in nominal operation and in cooling operation. Alternatively, at least two components from the group of closure devices and the shut-off device may not be independently controllable, but e.g. just matched.

It is an embodiment which is advantageous for a particularly varied air guidance that, in at least one third setting state, the closure device completely closes off the first air passage opening and the shut-off device partially shuts off the process air channel. The third setting state may also be referred to as an intermediate position. The second air passage opening, if present, may in particular be partially opened or closed.

Alternatively or additionally, in at least one further third setting state, the closure device may completely release the first air passage opening and the shut-off device may partly shut off the process air channel. The second air passage opening, if present, may in particular be partially opened.

Also, in at least one further third setting state, the closure device may partially release the first air passage opening and the shut-off device may partially shut off the process air channel. The second air passage opening, if present, may in particular be partially opened.

It is a particularly simple, inexpensive and compact implementable embodiment that the closure device and the shut-off device constitute parts of a lone air guiding device. If a second air passage opening with an associated further Closing device are present, may be advantageous for this purpose, the closure device for the first air passage opening, the further closure device for the second air passage opening and / or the shut-off device parts of a lone air guide. The parts may in particular be movable by means of a common actuator, which allows a particularly easy adjustment of a setting state.

It is a particularly simple, inexpensive and compact implementation that the air guiding device has a movable closure element, which has a first portion serving as the closure means and a second portion serving as the shut-off means and the further closure means.

In particular, the closure element may be a pivotable closure element, but may be e.g. also be a linearly displaceable closure element. The subregions may be e.g. be designed as a flap, valve and / or slide.

It is also an embodiment that the first heat exchanger or condenser and the second heat exchanger or heater are arranged side by side separated by a gap. The gap allows introduction of the ambient air behind the condenser and before the heating without complex structural measures. For this purpose, the first air passage opening is advantageously directly connected to the gap by ventilation technology. A direct connection may, in particular, be understood to be an air-technical connection in which no functional elements of the process air circuit or of the heat pump are arranged between the first air passage opening and the gap. The ventilation connection may be provided via a channel.

It is a practically particularly simple and safe implementable embodiment that the first portion of the closure element is designed as a slide and the second portion of the closure element is designed as a flap, so that in a first setting state (eg corresponding to a first end position) of the first portion of the closure element is pushed over the first air passage opening and the second portion rests on the second air passage opening and in a second setting state (eg corresponding to a second end position), the first portion of the closure element at least partially pushed away from the first air passage opening is and the second portion is lifted from the second air passage opening and rests on a seat in the process air duct.

In the first setting state, therefore, the first air passage opening are closed by the first portion and the second air passage opening by the second portion, while the process air passage is released. In the second setting state, the first air passage opening is at least partially (in particular completely) released by means of the first portion, the second air passage opening at least partially (in particular completely) opened by means of the second portion, and the process air channel at least partially (in particular completely) blocked.

The first subregion may in particular be a plate-shaped subregion. The second subregion may in particular be a plate-shaped subregion which projects perpendicularly from the first subregion. The first portion may rest in the first end position on the second air passage opening and sit in the second end position on a located in the process air duct seat.

The closure element may for example consist of plastic or metal. In particular, it may have been made in one piece, e.g. by means of a casting process, for example an injection molding process, and consequently a casting.

Generally, in the cooling mode, the ambient air may be sucked from the inside of the laundry dryer or from outside the laundry dryer. Also, in the cooling mode, the air flowing out of the process air duct may generally be discharged into the interior of the laundry drying device or out of the laundry drying device.

The object is also achieved by a method for operating a laundry drying apparatus, which has a laundry drying space whose openings are connected by a process air duct to a process air circuit, wherein in the process air duct, a heater for heating previously cooled process air and a process air blower for circulating the process air in the process air circuit are arranged, and which laundry drying apparatus comprises a heat pump with a heat exchanger serving as the heater, wherein in the method between a Recirculation mode for the process air in the process air circuit (eg during a nominal operation of the laundry dryer) and an exhaust air operation (eg during a cooling operation of the laundry dryer) is switched for ambient air, wherein during the exhaust air operation by means of the process air blower ambient air is passed through the heater and the process air duct between the heater and the laundry drying room is at least partially blocked or reduced cross-section. This method can be designed analogously to the laundry drying apparatus and has the same advantages.

For example, during exhaust air operation, a drive of the heat pump (e.g., a compressor) may operate or the drive may be in operation.

Fig.1

zeigt ein Funktionsschaltbild eines erfindungsgemäßen Wäschetrocknungsgeräts;

Fig.2

zeigt in einer teilweise transparenten Ansicht von schräg hinten Komponenten eines erfindungsgemäßen Wäschetrocknungsgeräts gemäß einer Weiterbildung der Fig.1 mit einer Luftleiteinrichtung in einer ersten Endstellung;

Fig.3

zeigt das erfindungsgemäße Wäschetrocknungsgerät als Strichzeichnung in einer zu Fig.2 analogen Darstellung;

Fig.4

zeig einen Ausschnitt aus Fig.3 im Bereich der Luftleiteinrichtung;

Fig.5

zeigt als Schnittdarstellung in Schrägansicht Komponenten des erfindungsgemäßen Wäschetrocknungsgeräts mit der Luftleiteinrichtung in einer zweiten Endstellung; und

Fig.6

zeigt als Schnittdarstellung in Seitenansicht Komponenten des erfindungsgemäßen Wäschetrocknungsgeräts mit der Luftleiteinrichtung in der zweiten Endstellung.

The above-described characteristics, features and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more clearly understood in connection with the following schematic description of an embodiment which will be described in detail in conjunction with the drawings.

Fig.1

shows a functional diagram of a laundry drying apparatus according to the invention;

Fig.2

shows in a partially transparent view obliquely from behind components of a laundry drying apparatus according to the invention according to a development of Fig.1 with an air guiding device in a first end position;

Figure 3

shows the laundry drying device according to the invention as a line drawing in one Fig.2 analog representation;

Figure 4

show a section Figure 3 in the area of the louver;

Figure 5

shows as a sectional view in an oblique view components of the laundry drying device according to the invention with the louver in a second end position; and

Figure 6

shows a sectional side view of components of the laundry drying device according to the invention with the louver in the second end position.

Fig.1 shows a laundry dryer 1 in the form of a circulating air dryer. The laundry drying apparatus 1 has a laundry drying room in the form of a horizontal rotatable laundry drum 2 with a front-side process air outlet opening 3 and a rear process air inlet opening 4. The process air outlet opening 3 and the process air inlet opening 4 are connected to one another by means of a process air channel 5 for circulating process air P. In the process air duct 5 - in this order in the flow direction of the process air P - a first heat exchanger, a second heat exchanger and a motor-driven process air blower 6 housed. The laundry drum 2 and the process air channel 5 represent at least during a normal drying operation or nominal operation a circulating closed process air circuit 2.5.

The first heat exchanger is designed as an evaporator (or "evaporator") 7 of a heat pump and serves as a condenser with respect to the hot-moist process air P emerging from the process air outlet opening 3. The process air P precipitates on the cool heat exchanger surfaces of the evaporator 7, so that it condenses out to form condensate K. The condensate K can be collected in a condensate tray 8.

The second heat exchanger is designed here as a condenser (or "condenser") 9 of the heat pump and serves as compared to the cool-dry process air P coming from the evaporator 7 as a heater. The condenser 9 thus heats the cool-dry process air P.

The process air blower 6 is arranged downstream of the condenser 9 and upstream of the process air inlet opening 4. Warm-dry process air P flowing into the process air inlet opening 4 can absorb moisture from the laundry and then emerge again from the process air outlet opening 3 as warm-moist process air, etc.

The heat pump is designed here as a compressor heat pump 7, 9, 10, 11, 12 and has in a basically known manner except the evaporator 7 and the condenser 9 a compressor 10 arranged therebetween as a drive and a throttle valve 11. These functional elements 7, 9, 10, 11 are interconnected by coolant lines 12 and form a coolant circuit for circulating coolant therein.

Between the evaporator 7 and the condenser 9 a Kanalabzweig 13 is provided on the process air channel 5, which has a first air passage opening in the form of a supply air opening 14. The supply air opening 14 is selectively openable and closable by means of a controllable closure device 15. The closure means 15 may be used to close the inlet air opening 14, e.g. a flap, a slider, a valve, etc. have.

Between the condenser 9 and the laundry drum 2, a second air passage opening in the form of an exhaust opening 16 is provided on the process air duct 5. The exhaust opening 16 is selectively openable and closable by means of another controllable closure device 17. The further closure device 17 may for closing the exhaust port 16 z. As a flap, a slider, a valve, etc. have.

Between the condenser 9 and the laundry drum 2, a shut-off device 18 is further provided in the process air channel 5, by means of which a cross-section of the process air channel 5 can be at least partially opened and closed or released and shut off. The shut-off device 18 may be used e.g. a flap, a slider, a valve, etc. have. The condenser 9 and the process air blower 6 serving as heating are thus arranged in the process air duct 5 between the supply air opening 14 and the shut-off device 18 and between the supply air opening 14 and the exhaust air opening 16.

The closure device 15, the further closure device 17 and the shut-off device 18 are connected to a control device 19 for their control or activation. The control device 19 can actuate the closure device 15, the further closure device 17 and / or the shut-off device 18 individually or in a predefined relationship to one another. The control device 19 may be connected to at least one temperature sensor for temperature-dependent control or actuation of these devices 15, 17 and 18, for example with a temperature sensor 20 arranged in the region of the condenser 9 and / or with a temperature sensor sensing a temperature of the compressor 10 (see FIG .). The controller 19 may alternatively or additionally make the control or activation of the devices 15, 17 and 18 dependent on a temporal progress of the drying process.

In particular, in a state of the laundry drying apparatus 1, in which no overheating of the refrigerant circuit or compressor heat pump 7, 9, 10, 11, 12 is present or threatened (eg in nominal operation), the control device 19 in a first setting state, the devices 15, 17th and 18 control so that the supply air opening 14 and the exhaust port 16 are closed and the process air channel 5 is released by the shut-off device 18. The process air P can thus circulate unhindered in the process air duct 5. There is virtually no secondary air flow from the supply air opening 14 to the exhaust port 16.

In order to avoid overheating of the coolant circuit or compressor heat pump 7, 9, 10, 11, 12, in particular of the compressor 10, the control device 19 can control the devices 15, 17 and 18 such that the closure device 15 simultaneously controls the inlet air opening 14 at least partially releases, the closure device 17, the exhaust port 16 at least partially releases and the shut-off device 18, the process air channel 5 at least partially blocked. Consequently, by the Zuluftöffnung 14 comparatively cool ambient air F z. B. sucked from the interior of the laundry dryer 1 in the process air duct 5. Due to the current process air blower 6, the ambient air F or a mixture of the ambient air F and the process air P passes over the condenser 9, which is thereby cooled. The condenser 9 flowing through the cooling liquid of the compressor heat pump 7, 9 to 12 is thereby also cooled more, so that overheating can be avoided.

The fact that the shut-off device 18 at least partially obstructs the process air channel 5 ensures that only little or even virtually no ambient air F gets into the laundry drum 2, which saves energy. Also, this prevents the amount of ambient air F reaching the evaporator 7 from being kept low or even completely suppressed, which keeps the efficiency of the compressor heat pump 7, 9, 10, 11, 12 high. These advantages are achieved, in particular, by the fact that the shut-off device 18 can close the process air duct 5 virtually completely and the supply air opening 14 and the exhaust air opening 16 can be virtually completely released.

Under a virtually complete shut-off or release can be understood in particular a shut off or release that for practical purposes of drying clothes is complete. For example, minor leaks may occur that do not significantly reduce efficiency.

This switching over of the devices 15, 17 and 18 can also be understood as meaning, in particular for cooling the compressor heat pump 7, 9, 10, 11, 12 from a recirculation mode for the process air P to an exhaust air mode for the ambient air F (and possibly a proportion of the process air P) can be switched, and vice versa.

Fig.2 and Figure 3 show in a view obliquely from behind a possible embodiment of the laundry drying apparatus 1 based on selected components in a partially transparent view. The laundry drying apparatus 1 has a bottom group 21, which carries a part of the process air duct 5, namely an air-technically connected to the front side process air outlet opening 3 of the laundry drum 2 (Fig.) Section 22, in a widened portion or a channel widening 23 of Process air duct 5 leads. In the channel widening 23 of the evaporator 7 and the condenser 9 are housed, such as in Figure 5 and Figure 6 shown.

Namely, the evaporator 7 is disposed closer to the portion 22, so that in the first setting state (corresponding to, eg, a nominal operation), the process air P flowing in through the portion 22 at the front into the channel widening 23 first passes through the evaporator 7 and then through the evaporator 7 Condenser 9 flows. The evaporator 7 is separated from the condenser 9 by an air gap 24. After passing through the condenser 9, the process air P is sucked through a short connecting portion 25 of the process air duct 5 to the process air blower 6. The process air blower 6 is designed as a radial fan. The process air blower 6 blows out the process air P through a further connecting section 26 of the process air duct 5 up to the rear process air inlet opening 4. The further connection portion 26 is in Fig.2 translucent and in Figure 3 drawn with a window available only for display. The connecting portion 26 is disposed on a rear end shield 36 which covers the process air inlet port through a perforated plate 37.

The connecting section 26 has the exhaust air opening 16 on one side. Fluidically behind the process air blower 6, the cover 26 also has a laterally inwardly directed projection which serves as an air baffle and as a seat 28, as explained in more detail below. The condenser 9 and the process air blower 6 are thus arranged in the process air duct 5 fluidically between the supply air opening 14 and the exhaust opening 16.

The channel branch 13 is formed as a separately manufactured component and with an open end from the outside to an in Figure 5 and Figure 6 shown opening 29 of the channel widening 23 attached. Namely, the channel branch 13 opens there into the air gap 24. The existing at the other end of the Kanalabzweigs 13 supply air opening 14 terminates near the exhaust port 16. The supply air opening 14 is directly connected with the air gap air-24. The supply air opening 14 and the exhaust opening 16 are arranged practically perpendicular to each other.

As especially with reference to Figure 3 and Figure 4 will be described in more detail, the closure device 15, the further closure device 17 and the shut-off device 18 are parts of a common air guiding device 30, 31 or are integrated in a common air guiding device. This allows a particularly simple, inexpensive and compact switching between at least two actuating states of the devices 15, 17 and 18. Namely, the louver 30, 31 only a pivotable, one-piece closure member 30 and an actuator 31 for pivoting the closure member 30. The closure element 30 may be, for example, a one-piece plastic or metal part. The actuator 31 may be, for example, a piezoelectric actuator or an electric motor and can be actuated by the control device 19.

The closure element 30 has a horizontally oriented axis of rotation 32 in the further connection portion 26 of the process air channel 5 close to an upper edge of the exhaust port 16. From the axis of rotation 32 from here a plate-shaped second portion 33 extends down so that it increases in the Figure 4 shown first actuating state, the exhaust port 16 covers from the inside in the manner of a flap and thus completely closes. By contrast, the process air channel 5 is practically not shut off in the first setting state. The first setting state corresponds to a first end position of the closure element 30.

With respect to the process air duct 5 on the outside, a first partial region 34 runs vertically from the second partial region 33. The first portion 34 is plate-shaped and flat has a circular plane in the plate-like curved course. At its edge facing away from the first portion 33, an air guide region 35, which extends perpendicularly to the rear, adjoins here with the same width as the first portion 34. In the first end position, the first portion 34 covers the supply air opening 14 and closes it completely. This ensures that in the drying operation without overheating (ie, the nominal operation) practically no ambient air is sucked in targeted, which would reduce the efficiency of the laundry dryer 1.

For example, for cooling the compressor heat pump 7, 9 to 12 can be pivoted by activation of the actuator 31, the closure element 30 from the first setting state or the first end position to a second setting state, which Figure 5 and Figure 6 is shown in more detail.

In the second setting state, which corresponds to a second end position, the second portion 33 now presses on the seat 28 and thus blocks the process air channel 5 between the process air blower 6 and the washing drum 2 practically completely. At the same time, the second portion 33 releases the exhaust port 16. The second subregion 33 thus serves both as part of the shut-off device 17 in the form of a shut-off flap for shutting off or releasing the process air channel 5 and as part of the further closure device 18 for shutting off or releasing the exhaust air opening 16.

Also, now the first portion 34 has been moved away from the supply air opening 14, which is thus also exposed or open. The first portion 34 thus serves as a closure device in the form of a slide for the supply air opening 14.

In addition, now a lower part of the exhaust port 16 is covered by the air duct 35. This prevents that a warm air flow emerging from the exhaust air opening 16 is at least partially sucked in through the supply air opening 14 again. A volume flow of a passing through the exhaust port 16 air flow is, however, not or not significantly reduced thereby.

If the closure element 30 is in the second end position, ambient air F is sucked from the interior of the laundry drying device 1 into the supply air opening 14 while the process air blower 6 is running and flows through the channel branch 13 into the air gap 24. From there, the ambient air F is sucked under heat through the condenser 9 to the process air blower 6, whereby the condenser 9 cools. Ambient air F warmed up by the process air blower 6 is blown back into the interior of the laundry drying apparatus 1 through the exhaust air opening 16. In the second end position, therefore, an exhaust air channel for the ambient air F is formed by the closure element 30, in which the condenser 9 and the process air blower 6 are arranged.

The actuator 31 may be able to pivot the closure element 30 only between the first end position and the second end position, which allows the use of a particularly simple actuator 31. Alternatively, the actuator 31 can adjust the closure element 30 to at least one discrete intermediate position or continuously between the two end positions.

For example, the closure element 30 may be adjustable such that the supply air opening 14 remains hidden up to an angular position of the closure element 30 of about 20 ° to 30 ° from the first end position through the first portion 34, while the process air channel 5 already by the second Subarea 33 is proportionally locked. In this way, the second subregion 33 can also be used to reduce the volume flow of the process air P-also independently of a cooling of the heat pump. This opens up additional possibilities for setting or regulating the drying process. For example, in a starting phase, the process air P can be throttled, so that the heat pump 7, 9 to 12 heats up faster and gets into a favorable process window.

Alternatively or additionally, the closure element 30 may be pivoted into at least one further setting state corresponding to at least one second intermediate position, in which the first portion 34 of the closure element 30 completely releases the supply air opening 14 and the second portion 33 only partially blocks the process air channel 5.

Alternatively or additionally, the closure element 30 may be pivoted into at least one further setting state corresponding to at least one third intermediate position, in which the first portion 34 of the closure element 30 partially releases the supply air opening 14 and the second portion 33 partially blocks the process air channel 5. Of course, the present invention is not limited to the embodiment shown.

Generally, "on", "an", etc. may be taken to mean a singular or a plurality, in particular in the sense of "at least one" or "one or more" etc., unless this is explicitly excluded, e.g. by the expression "exactly one", etc.

Also, a number may include exactly the specified number as well as a usual tolerance range, as long as this is not explicitly excluded.

LIST OF REFERENCE NUMBERS

1

Laundry drying device

2

washing drum

3

Process air outlet opening

4

Process air inlet port

5

Process air duct

6

Process air fan

7

Evaporator

8th

Drain pan

9

condenser

10

compressor

11

throttle valve

12

Coolant line

13

channel branch

14

air intake opening

15

closure device

16

exhaust vent

17

Further closure device

18

shut-off

19

control device

20

temperature sensor

21

underbody

22

Section of the process air duct

23

channel widening

24

air gap

25

Connecting section of the process air duct

26

Further connection section

28

Seat

29

Opening the channel widening

30

closure element

31

actuator

32

axis of rotation

33

Second subregion of the closure element

34

First part of the closure element

35

Luftleitleitbereich

36

Rear end shield

37

Punched sheet metal

F

ambient air

P

process air

Claims (11)

Clothes drying device (1), - Having a laundry drying room (2) with a process air inlet opening (4) and a process air outlet opening (3), which openings by means of a process air duct (5) to a process air circuit (2, 5) are interconnected in the process air duct (5), a condenser (7) for cooling process air (P) leaving the laundry drying room (2), a heater (9) for heating previously cooled process air (P) and a process air blower (6) for circulating the process air Process air (P) in the process air circuit (2, 5) are arranged, further comprising - A heat pump (7, 9-12) with a drive (10), serving as the capacitor (7) first heat exchanger and serving as the heater (9) second heat exchanger, also having - A controllable closure device (15) for selectively opening and closing a first air passage opening (14) of the process air circuit (2, 5) and comprising a controllable shut-off device (18) for selectively opening and blocking the process air duct (5), in which - The heater (9) and the process air blower (6) in the process air channel (5) between the first air passage opening (14) and the shut-off device (18) are arranged and - The closure device (15) and the shut-off device (18) are controllable so that at the same time the closure device (15) at least partially releases the first air passage opening (14) and the shut-off device (18) at least partially shuts off the process air channel (5), - The shut-off device (18) alternately the process air duct (5) at least partially releases or shuts off and a second air passage opening (16) of the process air circuit (5) by means of a further closure device (17) is at least partially closed or released, the heater (9) and the process air blower (6) are arranged in the process air duct (5) between the first air passage opening (14) and the second air passage opening (16), - The closure device (15), the further closure device (17) and the shut-off device (18) parts of a lone louver (30, 31) represent and - The louver (30, 31) comprises a movable, in particular pivotable, closure element (30) serving as a closure means (15) first portion (34) and one serving as the shut-off device (18) and the further closure means (17) second subregion (33). Laundry drying apparatus (1) according to claim 1, wherein - In a first setting state, the closure device (15), the first air passage opening (14) completely closes and the shut-off device (18) the process air passage (5) completely free and - In a second setting state, the closure device (15) the first air passage opening (14) releases and the shut-off device (18) the process air channel (5) completely shuts off. Laundry drying device (1) according to one of the preceding claims, wherein in at least one third setting state, the closure device (15) completely closes or completely releases the first air passage opening (14) and the shut-off device (18) partially shuts off the process air passage (5). Laundry drying apparatus (1) according to one of the preceding claims, wherein the heater (9) and the process air blower (6) but not the condenser (7) in the process air duct (5) between the first air passage opening (14) and the second air passage opening (16 ) are arranged. Laundry drying apparatus (1) according to claim 4, wherein the air guiding device (30, 31) has a closing element (30) which can be moved, in particular can be pivoted, by means of an actuator (31). Laundry drying apparatus (1) according to one of the preceding claims, in which - The capacitor (7) and the heater (9) through a gap (24) are arranged separately side by side and - The first air passage opening (14) is directly connected to the air gap with the gap (24). Laundry drying apparatus (1) according to one of the preceding claims, in which - The first portion (34) of the closure element (30) is designed as a slide, - The second portion (33) of the closure element (30) is designed as a flap. Laundry drying apparatus (1) according to one of claims 2 to 7, wherein in a first end position corresponding to the first setting state, the first subregion (34) of the closure element (30) is pushed over the first air passage opening (14) and the second subregion (33) rests on the second air passage opening (16) and in a second end position corresponding to the second setting state, the first subregion (34) of the closure element (30) is at least partially pushed away from the first air passage opening (14) and the second subregion (33) is lifted off the second air passage opening (16) and on one Seat (28) in the process air duct (5) rests. Laundry drying apparatus (1) according to one of the preceding claims, wherein the heat pump (7, 9-12) a compressor heat pump with a compressor (10) as the drive, an evaporator (7) as the condenser and a condenser (9) as the heating is. Method for operating a laundry drying apparatus (1) according to one of the preceding claims, which has a laundry drying space (2) whose openings (3, 4) are connected to one another by means of a process air duct (5) to form a process air circuit, wherein in the process air duct (5) Heating for warming up previously cooled process air (P) and a process air blower (6) for circulating the process air (P) arranged in the process air circuit and which laundry drying apparatus (1) has a heat pump (7, 9-12) with a heat exchanger serving as the heater (9), wherein in the method between a recirculation operation for the process air (P) in the process air circuit (5) and a Exhaust air operation for ambient air (F) is switched, wherein during the exhaust air operation by the process air blower (6) ambient air (F) via the heater (9) is passed and the process air duct (5) between the heater (9) and the laundry drying room (2) at least partially blocked. Method according to Claim 10, in which a drive (10) of the heat pump (7, 9-12) is operated during the exhaust air operation.

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