WO2023186283A1

WO2023186283A1 - Laundry treatment method and machine using a heat pump with an evaporator regeneration

Info

Publication number: WO2023186283A1
Application number: PCT/EP2022/058371
Authority: WO
Inventors: Maurizio Del Pos; Angelo LE PERA
Original assignee: Electrolux Appliances Aktiebolag
Priority date: 2022-03-30
Filing date: 2022-03-30
Publication date: 2023-10-05

Abstract

Method for operating a laundry treatment machine comprising: a cabinet (4) housing a tub (58), a heat pump having a compressor (36), an evaporator (102) and a condenser (81), the condenser (81) being adapted to heat washing liquid, an evaporator tank (100) housing at least a portion of the evaporator (102), wherein the evaporator tank (100) is a tank for storing a heat exchanging medium, a regeneration unit (76, 132a, 132b) adapted to circulate the washing liquid with a regeneration pump (76) from the tub (58) or sump (140) through or along the evaporator tank (100) and back to the tub (58), in particular a sump (140), or a filter arranged upstream of the regeneration pump (76), and a refrigerant flow changing device (78) adapted to change between a normal operation mode of the heat pump and a reverse operation mode of the heat pump.The method foresees to operate the laundry treatment machine in a first regeneration mode A) where the heat pump is in the reverse operation mode, or in a second regeneration mode B) where the regeneration unit is circulating the washing liquid. A laundry treatment machine is also disclosed and claimed.

Description

Laundry Treatment Method and Machine using a Heat Pump with an Evaporator Regeneration

The present invention relates to a method for operating a laundry treatment machine, in particular a washing machine for washing laundry or a washer dryer for washing and drying laundry. A regeneration cycle/function is implemented for regenerating and deicing a heat exchanging medium in an evaporator tank.

EP 2 206 824 A2 suggests a washing machine with an evaporator arranged within an evaporator tank and a condenser of a heat pump for heating the washing water during a washing cycle. Waste heat of the washing liquid is used for heating the evaporator at the end of the wash phase.

It is an object of the invention to provide a method of operating a laundry treatment machine and such a machine with an improved heat regeneration management to improve the energy efficiency of the machine.

The invention is defined in claims 1 and 8, respectively. Particular embodiments are set out in the dependent claims.

According to claim 1, a method for operating a laundry treatment machine, in particular a washing machine or a washer dryer, is provided. The laundry treatment machine comprises: a cabinet housing a tub and a drum rotatably arranged in the tub for washing laundry therein, a heat pump having a compressor, an evaporator and a condenser, the condenser being adapted to heat washing liquid, an evaporator tank housing the evaporator or at least a portion of the evaporator, wherein the evaporator tank is a tank for storing a heat exchanging medium, a regeneration unit adapted to circulate the washing liquid with a regeneration pump from the tub or sump through or along the evaporator tank and back to the tub, in particular a tub sump, or a filter arranged upstream of the regeneration pump, and a refrigerant flow changing device adapted to change between a normal operation mode of the heat pump and a reverse operation mode of the heat pump. In the normal operation mode of the heat pump, the condenser is adapted to heat the washing liquid and the evaporator is adapted to cool the heat exchanging medium. In the reverse operation mode of the heat pump, the condenser is adapted to cool the washing liquid and the evaporator is adapted to heat the heat exchanging medium. Operating the laundry treatment machine comprises: operating the laundry treatment machine in a first regeneration mode A) where the heat pump is in the reverse operation mode, and operating the laundry treatment machine in a second regeneration mode B) where the regeneration unit is circulating the washing liquid.

Herein the "washing liquid" is any liquid for treating the laundry in the tub. E.g. a washing liquor used during the washing phase of the rinsing water used during a rinsing phase or an additive liquor used during an additive treatment phase, like sterilization, bleach, waterproofing. In specific contexts below, 'washing liquid' refers to 'washing liquor', e.g. in the context of the washing phase or washing temperature.

'Through' the evaporator tank means that the washing liquid flows via an inlet into the evaporator tank and via an outlet out of the evaporator tank. In this case the heat exchanging medium is the washing liquid. 'Along' means that the washing liquid flows along the evaporator tank such that it is in heat exchanging contact with the heat exchanging medium in the evaporator tank such that heat is exchanged between the washing liquid and the heat exchanging medium. In this case the washing liquid does not replace or displace the heat exchanging medium.

'Regeneration mode' means that in this mode the evaporator tank is regenerated, i.e. heat is transferred to the evaporator tank, in particular to the heat exchanging medium within the evaporator tank. Regeneration modes A) (i.e. transferring heat from the refrigerant to the evaporator tank) and B) (i.e. circulating washing liquid from the tub through or along the evaporator tank) may be used for regenerating the evaporator tank, in particular for melting ice formed within the evaporator tank. Thereby preferably from a running washing cycle heat is deposited in the evaporator tank which then can be extracted in the next washing cycle, for example for heating the washing liquid. Therefore, the energy efficiency of the laundry treatment machine may be improved.

In case of regeneration mode B), i.e. washing liquid circulated through or along the evaporator tank, the evaporator tank may be a flow-through tank such that the heat exchanging medium within the evaporator tank is replaced or displaced by the washing liquid flowing through the evaporator tank. Here preferably the evaporator tank is a single chamber tank. Alternatively the evaporator tank may comprise a first and a second chamber container, wherein the first container chamber houses the evaporator or at least a portion of the evaporator and permanently stores the heat exchanging medium and the second container chamber is a flow-through chamber comprising an inlet and outlet, wherein the second container chamber is in heat contact with the heat exchanging medium in the first container chamber. Washing liquid drained from the tub by the regeneration pump is passed through the second container chamber via the inlet and outlet. This is described further below in detail.

During regeneration mode A), washing liquid drained from the tub is circulated through the condenser and is re-introduced into the tub. Thus, in the condenser working as an evaporator in the regeneration mode A), the refrigerant is heated up and the heated refrigerant heats the washing liquid within the evaporator tank. Also in the reverse operation of the heat pump in the regeneration mode A) the heat of the compressor is deposited in the evaporator tank.

Regeneration mode B) is preferably used when the evaporator tank is not fully iced, i.e. for melting small amount of ice. If e.g. the presently executed wash phase is a wash phase of a short time washing program and/or a low temperature wash phase of a low temperature wash program, the amount or degree of ice formed in the evaporator tank is low and the need for regeneration is low. Regeneration mode B) may be more efficient if not all heat exchanging liquid is iced and some of it is still in liquid form in the evaporator tank. In the two-chamber evaporator tank ("along the tank") the remaining liquid heat exchanging medium more efficiently distributes the heat after heat exchange with the circulated washing circuit. In case of the single-chamber evaporator tank ("through the tank") the circulated washing liquid from the tub replaces or mixes with the liquid washing liquid inside the evaporator tank providing increased heat exchange.

Preferably, the method further comprises operating the laundry treatment machine during a laundry treatment cycle at least partially simultaneously in the first and second regeneration mode A)+B). Then the heat transfer from the washing liquid into the heat exchanging medium in the evaporator tank is maximized and maximum total heat can be transferred into the evaporator tank or the time required for transferring a predefined amount of heat is minimized.

Alternatively or additionally the method further comprises operating the laundry treatment machine at least partially exclusively in the first and/or in the second regeneration mode A) or B). Preferably, the method further comprises operating the laundry treatment machine during a laundry treatment cycle in the first regeneration mode A) or in the second regeneration mode B) or simultaneously in the first and second regeneration mode A)+B) depending on one or more of the following operation parameters of the laundry treatment machine: a) a laundry treating program selected by a user; b) a laundry washing liquid temperature; c) a number of rinsing phases selected by the user or provided by a laundry treatment machine control unit; d) an operation time of the heat pump system to heat up the laundry washing liquid; e) a signal of a sensor indicating the freezing status of the laundry washing liquid in the evaporator tank; f) a regeneration type user selection; g) an alarm signal indicating that one of the first and second regeneration modes is not available; h) a user command causing a modification in the execution of phases of an originally started laundry treating program; and i) a signal of a sensor detecting the temperature of the laundry washing liquid in the tub and/or in the evaporator tank.

According to parameters a) and/or b): Preferably regeneration mode B) is selected if a half load cycle (i.e. small amount of ice is formed in the evaporator tank, e.g. a short time program) and/or a laundry treating temperature less than 50 °C, 45 °C, 40 °C or 35 °C is selected by the user. A low temperature and/or a short time program results in small amount of ice. Regeneration mode A) may be selected if a long main wash program and/or a high washing liquid temperature is selected by the user. Long washing programs and/or high washing temperatures may result in a high volume or rate of ice formed within the evaporator tank. In parameter b) the temperature is preferably selected by the user, for example if the respective washing program allows selection of a temperature by the user. Otherwise the temperature may be selected via the washing program by the user out of a plurality of different washing programs available for the laundry treatment machine.

According to parameter c): If there is a plurality of rinsing phases, e.g. three rinsing phases, the laundry treatment machine may be operated in the first rinsing phase only in regeneration mode B), in the second rinsing phase only in regeneration mode A) and in the third rinsing phase in regeneration modes A) and B). Thereby in the first rinsing the higher or non-reduced rinsing temperature preserves a better rinsing efficiency for dissolving detergent residuals and in the last rinsing full heat of the rinsing liquid is extracted.

According to parameter d): If the operation time is long, the regeneration period(s) can be extended. For extraction the same amount of heat longer time is available and mode B) can be used instead of A) which would be required at shorter regeneration periods. Then mode B) would be used and the heat pump would be deactivated as the regeneration pump motor consumes less power than the compressor motor.

According to parameter e): The washing machine may comprise for regeneration mode B) a flowmeter for measuring the washing liquid flow through the evaporator tank and/or a pressure/temperature sensor at the evaporator in the evaporator tank for measuring the pressure/temperature within the evaporator tank. E.g. a sensor may detect a huge amount of ice within the evaporator which leads to a low gradient of temperature change over time in the evaporator tank. Then regeneration mode B) would be less efficient and regeneration mode A) is therefore selected in dependency of the signal of the sensor. Mode A) can transfer more heat in the same time than mode B) and after the regeneration more heat capacity is available from the evaporator tank for the following washing cycle.

Herein the washing program defining the washing cycle is not a cold or regeneration washing. In the regeneration washing the liquid is not heated by the heat-pump system at least at the start during a washing phase, but is cooled permanently or at the beginning for a cold wash, e.g. at wash liquid temperature below the tap water temperature.

According to parameter f): The user may be able to select the first and/or second regeneration modes A)+B) by an input device. E.g. if the user does not have much time and wants a fast wash, she/he may select regeneration mode A).

According to parameter g): If one of the first and second regeneration modes may not be available, e.g. if the heat pump system has a defect, regeneration mode A) is not available and regeneration mode B) is selected. In addition, a heater arranged within the tub for heating the washing liquid may be used for additionally heating the washing liquid during regeneration mode B) such that the regeneration is speed up. The laundry treatment apparatus may comprise a heater which is preferably an electrical heater. Preferably and if sufficient heat can be extracted from the evaporator tank, the washing liquid is heated exclusively by the condenser of the heat pump system.

However the heater is preferably provided to co-heat the washing liquid if the washing temperature to be achieved is higher than can be achieved by the condenser-heating and/or the heating time for exclusive condenser heating would extend the wash time to overall wash cycle times inconvenient for the user.

If e.g. regeneration mode B) is not available, regeneration mode A) is selected and the evaporator tank is regenerated by regeneration mode A), wherein in addition the heater within the tub may be used for heating the washing liquid and thus for increasing the heat exchange with the refrigerant in the condenser. In this case, the regeneration by regeneration mode A) is supported by the heater. This may be applicable if e.g. the temperature of the washing liquid within the tub is low.

According to parameter h): The user may modify the main wash phase and/or the rinsing phase(s); e.g. the user may shorten the selected treating program by e.g. skipping rinsing phases (e.g. when the user comes home and does not want to wait any longer). By shortening of the treating program, the time for regeneration is reduced such that in this case regeneration mode A) instead of B) or A)+B) instead of A) may be preferred. The user may change the main wash phase such that the use of the heat pump is influenced and therefore the formation of ice within the evaporator tank is influenced. E.g. if heat pump use is decreased less ice is formed in the evaporator tank such that regeneration mode B) may be preferred and if heat pump use is increased by the modification of the user more ice is formed within the evaporator tank such that regeneration mode A) may be preferred for regeneration of the evaporator tank. Or the user may skip the regeneration modes A) and/or B) when he does not have much time and wants to start a further washing program.

According to parameter i): High temperature of the washing liquid (e.g. above 60 °C) within the tub may be achieved by operation of the heat pump (alternatively or in addition by using the electrical heater in the tub). Heating the washing liquid with the heat pump is achieved by extracting the heat of the washing liquid within the evaporator tank via the refrigerant. Therefore, the washing liquid within the evaporator tank cools down. The higher the washing liquid temperature, the higher the amount of heat extracted from the washing liquid within the evaporator tank and thus the higher the amount of ice in the evaporator tank. If the temperature is high, regeneration mode A) may be preferred instead of regeneration mode B).

Preferably, the first regeneration mode A) and/or the second regeneration mode B) are executed at the end of a main wash phase of a washing program and/or during at least one rinsing phase.

Preferably, regeneration modes A) and/or B) may be executed during at least the last 20, 30, 40, 50 or 60 mins of a main wash phase of a washing program. Regeneration mode A) may be executed during the at least one rinsing phase. Regeneration modes A) and/or B) are preferably executed at the end of a main wash phase of a washing program. Preferably, the regeneration modes A) and/or B) are executed during the complete rinsing phase/s.

If the washing program includes e.g. three rinsing phases, the regeneration may be executed only in the second and third, but not in the first rinsing phase. During the main wash phase the whole washing group is heated up. The higher the washing liquid temperature of the main wash phase, the higher the heat in the whole washing group at the end of the main wash phase before the first rinsing phase. Therefore, in the first rinsing phase, preferably no regeneration is executed such that the heat in the washing group can be used for the rinsing. This may make it possible to rinse out any remaining or substantially remaining detergent from the machine and clothes, as the temperature of the whole washing group ensures that the detergents remain in a dissolved state. Alternatively, if the selected washing program comprises a plurality of rinsing phases or if a plurality of rinsing phases is selected by the user, the regeneration may be distributed over all of the rinsing phases.

Preferably, the regeneration pump of the regeneration unit is a variable speed pump. The variable speed pump (VSP) may be operated with different speed levels. Therefore it may be possible to adjust the regeneration speed of the evaporator tank during the regeneration mode B).

The speed of the pump may be adapted in dependency of current washing parameters, wherein the washing parameter is one or more of: temperature and/or icing degree in evaporator tank; and/or temperature of the washing liquid in the tub, i.e. in case water is drained or circulated. E.g. at high (e.g. above 60 °C) washing liquid temperature, huge amount of ice is formed within the evaporator tank. Thus, the circulation speed of the variable speed pump may be increased since due to the high washing liquid temperature a shorter heat exchange interaction in the evaporator tank may be needed for melting of the ice within the tank.

E.g. at low (e.g. below 60 °C) washing liquid temperature, less amount of ice is formed within the evaporator tank. Thus, the circulation speed of the variable speed pump may be decreased since due to the low washing liquid temperature a longer heat exchange interaction in the evaporator tank for melting of the ice may be desired.

The variable speed pump may be operated with a constant speed level or with a speed driving profile consisting of a combination of a number of different speed levels. A speed level and/or a speed driving profile of the variable speed pump may be selected in dependency of at least one of the following parameters:

- a laundry treating program selected by a user;

- a laundry washing liquid temperature;

- an operation time of the heat pump system to heat up the laundry washing liquid;

- a signal of a sensor indicating the freezing status of the laundry washing liquid in the evaporator tank;

- a user command causing a modification in the execution of phases of an originally started laundry treating program;

- a signal of a sensor detecting the temperature of the laundry washing liquid in the tub and/or in the evaporator tank; and

- a number of rinsing phases selected by the user or provided by a laundry treatment machine control unit.

Evaporator / Evaporator Tank:

The evaporator tank may have a capacity in the range between 4.0 - 4.5, 4.2 - 4.7, 4.4 - 4.9 or 4.6 - 5.2 liters, preferably 4.7 liters. The capacity of the evaporator tank is preferably enough for one main wash phase. E.g. to heat up 4 liter of washing water (tap water) in the tub to 40 °C.

Preferably, the evaporator tank comprises an upper region accommodating a first portion of the evaporator and a lower region accommodating a second portion of the evaporator, wherein the first and second portion of the evaporator are arranged at vertically different levels, and wherein the horizontal cross-section area of the lower region is less than the horizontal cross-section area of the upper region. A 'region' represents a volume region within the evaporator tank having a vertical extension and being defined between a (fictive) lower and upper horizontal crosssection area within the inner tank space. The vertical extension is such that a respective portion of the evaporator is positioned within the volume region. Preferably the horizontal cross-section area of a (upper/lower/intermediate) region is an average horizontal cross-section area of the respective region, e.g. averaged over all crosssections over the vertical extension of the respective region. The lower or upper regions are not regions located within a stub or connector which is connected to the evaporator tank. I.e. the regions are regions conventionally considered to be arranged within the tank volume as such and not within extensions external to the tank volume provided e.g. for peripheral (liquid) connection purposes.

The volume region of the lower region is arranged below the volume region of the upper region. In top view the volume region (e.g. the upper and lower horizontal crosssection area) may be above each other or at least partially offset to each other. Preferably there is a full or partial overlap of the upper and lower region when seen from above - i.e. the vertical projection of the lower region onto the upper region overlaps at least partially with the upper region.

'Vertically different levels' means that the lower region accommodating the second portion of the evaporator and the upper region accommodating the first portion of the evaporator are arranged in volume regions at different vertical height within the tank inner volume, i.e. the volumes of the upper and lower regions have no overlap volume.

The evaporator tank is external to the tub, in particular the tank is arranged above the tub and/or extends below the top module, more preferably within the top module. The evaporator tank is preferably a continuous tank, in particular the lower and upper region of the evaporator tank are connected to each other forming a single tank. Two single tanks that are only fluidly connected to each other are excluded by this definition.

In case of regeneration mode B):

The evaporator tank is a) a flow through-tank comprising an inlet and an outlet, wherein washing liquid from the tub is passed through the evaporator tank via the inlet and outlet and wherein the washing liquid is the heat exchanging medium. Or the evaporator tank is b) a two-chamber tank comprising a first and a second container chamber, wherein the first container chamber houses the evaporator or at least a portion of the evaporator and permanently stores the heat exchanging medium, wherein the second container chamber is a flow through-tank chamber comprising an inlet and an outlet, wherein the second container chamber is in heat contact with the heat exchanging medium in the first container chamber. Washing liquid drained from the tub by the regeneration pump (mixing pump) is passed through the second container chamber via the inlet and outlet. An inlet of the regeneration pump (mixing pump) is connected to the tub or the sump of the tub and an outlet of the regeneration pump is connected to the inlet of the second container chamber.

By circulating the washing liquid through the second container chamber, heat of the washing liquid is transferred to the heat exchanging medium stored in the first container chamber, and therefore, to melt the frozen heat exchanging medium (e.g. ice) formed in the first container chamber. Thus frozen medium that has formed in the tank (i.e. first container chamber) can be dissolved by the circulation of the washing liquid through the second container chamber which results in an improved operation efficiency of the laundry treatment machine.

Preferably, the arrangement of the evaporator tank with the upper region and lower region accommodating portions of the evaporator are arranged in the first container chamber of the evaporator tank.

According to version b) of the evaporator tank, two fluidly separated chambers are formed in one container forming the evaporator tank, wherein the container is integrated in the top. Preferably the container is formed integrally with the top or integrally with a tray element of the top.

The 'washing liquid' may be the washing liquid used during a washing phase or the rinsing liquid used during a rinsing phase or generally the treatment liquid used during any of the laundry treatment phases.

'Permanently storing' means that in normal user operation the heat exchanging medium is not exchanged or refreshed. The medium may be filled during manufacturing of the machine or when setting the machine to operation at the installation place. The medium may be exchanged by maintenance case e.g. by a service person. When permanently storing the heat exchanging medium, a medium may be used having a higher heat storing capacity and/or a higher latent heat (enthalpy of fusion) than the washing liquid which basically is water.

Applicable for versions a) and b) of the evaporator tank: The 'washing liquid drained from the tub' is the washing liquid that was used for treatment of laundry in the tub and which is extracted from the tub. The extraction from the tub may be made through an outlet provided at the tub wall or preferably through the sump of the tub or a sump portion fluidly connected to the tub. Preferably the washing liquid is extracted downstream of a filter which is filtering the washing liquid extracted from the tub or sump. The filter is preferably arranged upstream of the regeneration pump (mixing pump). Preferably the filter housing in which the filter is arranged is part of the sump. Filtering the washing liquid avoids deposition of fluff and particles in the evaporator tank and the lines to and from the evaporator tank.

Preferably, the washing liquid that has passed through the second container chamber (version b)) or through the evaporator tank (version a)) is reintroduced into the tub, preferably via a bellow of the tub, a sump, or a filter, preferably at a position in the sump upstream of the filter. The filter can be the filter which is normally provided in the passage from the tub (e.g. from the sump) to a drain pump which is draining the washing liquid e.g. after a washing or rinsing phase.

Applicable for versions a) and b): Preferably the washing liquid flows back into the tub or sump fluidly connected to the tub or another fluid line fluidly connected to the tub (e.g. the detergent housing or a passage from the detergent drawer to the tub). Alternatively and/or selectively the fluid is passed into a drain line that is used by the drain pump for draining washing or rinsing liquid. A non-retum valve may be arranged downstream of the drain pump such that washing liquid drained by the drain pump or being drained after having passed the evaporator tank can not flow back to the sump/tub through the drain pump.

Applicable for versions a) and b): Preferably the washing liquid is extracted from the tub, the sump or any other line fluidly connected to the tub by the regeneration pump. The regeneration pump may be operated at the end of a laundry treatment phase (e.g. washing phase or rinsing phase). Preferably the regeneration pump is operated before operating the drain pump or at least partially simultaneously with operating the drain pump during the respective wash phase (e.g. wash cycle or rinse cycle). E.g. when the regeneration pump is fluidly connected to the sump and when then or simultaneously the drain pump is operated, 'fresh' washing liquid is extracted by the drain pump via the sump from the tub such that when the regeneration pump is also fluidly connected to the sump the regeneration pump at least partially extracts washing liquid freshly provided from the tub by the activity of the drain pump. Alternatively, the washing liquid in the tub flows via the sump to the regeneration pump due to gravity. A circulation of the 'same' washing liquid from the sump to the evaporator tank is avoided such that fresh and warmer washing liquid is fed into the circulation to the evaporator tank. Preferably the washing machine comprises a control unit that is adapted to control the operation of the regeneration pump as described herein and in particular as described in this paragraph.

Applicable for version b): Preferably the washing liquid is fed to the second container chamber via pipe sections which extend through the first container chamber, wherein in particular a first pipe end forms the inlet of the second container chamber, and a second pipe end forms the outlet of the second container chamber. Thus, the washing liquid is guided through the first container chamber.

Preferably, the inlet and outlet of the second container chamber are arranged at the bottom of the second container chamber. More preferably, the pipes extend vertically or substantially vertically from the bottom of the first container chamber to the bottom of the second container chamber.

Preferably, the first pipe connects an inlet of the first container chamber with the inlet of the second container chamber, and the second pipe connects an outlet of the first container chamber with the outlet of the second container chamber, in particular such that the washing liquid is guidable through the first container chamber. The inlet and outlet of the first container chamber are preferably arranged at the bottom of the evaporator tank, in particular at the bottom of the first container chamber. Alternatively, the inlet and outlet of the first container chamber may be arranged at a side wall of the first container chamber, wherein in this case the pipes extend from the side wall to the inlet and outlet of the second container chamber.

Preferably, the second container chamber is arranged above and in heat contact with the first container chamber. Preferably, when the heat exchanging medium within the evaporator tank is not iced or only partially iced a gaseous volume is maintained above the heat exchanging medium. As long as the gaseous volume is present, a reduced heat exchange between the heat exchanging medium in the first container chamber and the washing liquid in the second container chamber is accepted. When the heat exchanging medium is completely iced, the gaseous volume may be filled by the iced heat exchanging medium and a heat contact between the washing liquid flowing through the second container chamber and the iced heat exchanging medium is obtained. This arrangement ensures that frozen heat exchanging medium that has formed in the first container chamber can be dissolved by the circulation of the washing liquid through the second container chamber which results in an improved operation efficiency of the laundry treatment machine.

Throughout this description the terms 'ice', 'freezing' and 'melting' generally describe the change of phase states from liquid to solid and vice versa, respectively, independent whether it relates to water (washing = laundry treatment water) as heat exchanging medium or any other heat exchanging medium used for storing/releasing heat accompanied by a phase change, e.g. the liquid/solid phase change.

Preferably, the first and second container chambers are formed by a single or integral container. "Single or integral container" means that the second container chamber and the first container chamber share a common wall, in particular a separation wall, i.e. only a single container, namely the evaporator tank, is visible from the outside. Preferably, the separation wall forms the bottom wall of the second container chamber and the top wall of the first container chamber. This results in less risk of leakage as the first and second container chambers share a common wall. Preferably, the integral container is also integrally formed with the top or integrally with the tray element of the top.

More preferably a separation wall is inserted in the container separating the first and second container chamber from each other. The separation wall fluidly separates the first and second container chambers from each other. Preferably, the separation wall is arranged horizontally between the first and second container chambers. As the separation wall may be not or only very slightly mechanically loaded, the material of the separation wall can be freely chosen. The separation wall may be made of e.g. thin Aluminum for improved heat exchange between the first and second container chambers. The separation wall may be made of a flexible material with less stiffness for compensating the volume change of the mediums within the first and/or second container chamber, in particular of the heat exchanging medium in the first container chamber. In this case, no gaseous volume may be provided above the heat exchanging medium in the first container chamber as the volume change of the medium when icing may be compensated by an elastic deformation of the flexible separation wall.

Preferably, the second container chamber comprises guiding elements for guiding the washing liquid along a predetermined path within the second container chamber. More preferably, the guiding elements are formed such that the liquid passes through the second container in meandering shape/form. The guiding elements may be configured such that the inlet and outlet of the second container chamber are separated from each other. Thus, the washing liquid flowing into the second container chamber has to flow along the whole predetermined path before exiting the second container chamber. Preferably, the guiding elements are configured such that the washing liquid flows along the whole or substantially whole top surface of the first container chamber.

Preferably, the guiding elements are arranged at the upper surface of the separation wall and/or the lower surface of the evaporator tank cover, more preferably are formed in a single piece with the separation wall and/or the evaporator tank cover.

In case the second container chamber is formed within or by the evaporator tank cover, the guiding elements may be arranged at the upper surface of the tank cover. The guiding elements preferably protrude from the upper surface of the evaporator tank cover into the second container chamber. Preferably, the top of the tank cover is covered by a further cover (e.g. a lid).

Preferably the guiding elements extend vertically over the entire height of the second container chamber and/or between the upper surface of the separation wall and the lower surface of the further cover (i.e. a cover covering the second container chamber from above).

The circulation of the washing liquid in versions a) and b) (second regeneration mode B)) between the tub and the tank ensures that the evaporator tank is deiced and thus it may be ensured that it is always possible to drain water from the tank.

Applicable for version a): Preferably an overflow is arranged within the evaporator tank, wherein the overflow may be configured such that the tank is only partially filled with the washing liquid and a gaseous volume is maintained above the washing liquid level. In particular, the washing liquid only rises to a predefined washing liquid level and then flows off the evaporator tank via the overflow. Applicable for version a): Preferably the evaporator tank, in particular the evaporator tank cover, comprises a separation (guiding) element arranged at the top of the evaporator tank and facing the inside of the tank, wherein the separation element is configured such that the inlet and outlet within the tank are separated from each other and/or the washing liquid is guided along a predefined path within the tank (or along an at least partially predefined path within the tank). The predefined path may ensure that the supplied water from the tub always has to flow over the entire or substantially entire ice formed around the evaporator pipes. I.e. when the ice is melt, the water may pass past all or substantially all pipes of the evaporator before it is discharged at the outlet (via overflow) of the tank. I.e. during melting of the ice in the evaporator, the water may flow past the entire ice formed in the evaporator. In particular the separation wall provides that in case of frozen liquid in the tank the liquid supplied into the tank flows over the surface of the frozen liquid before exiting the tank.

Preferably, the evaporator tank comprises at least one intermediate region located between the upper region and the lower region, wherein the at least one intermediate region preferably comprises a third or further portions of the evaporator. The 'intermediate region' may have a horizontal cross-section area which is between the horizontal cross-section areas of the upper and lower region ('horizontal cross-section area' can here also be understood as the average horizontal cross-section area over the whole vertical range of the respective region).

Preferably, the horizontal cross-section areas decrease in steps from the upper region to the intermediate region and from the intermediate region to the lower region. Preferably, the tank comprises at least two steps, when the tank is seen in vertical cross-section in front view of the washing machine. The upper region, the at least one intermediate region and the lower region form a continuous evaporator tank. At least one side wall of the tank enclosing the volume of the intermediate region may be a vertical, inclined or rounded side wall.

Preferably, the refrigerant circuit of the heat pump is designed such that the refrigerant enters the evaporator at the first evaporator portion of the lower region, and/or the refrigerant exits the evaporator in the evaporator tank from the second portion of the evaporator in the upper region, and/or the heat pump further comprises an expansion device positioned in the refrigerant circuit upstream of the second portion of the evaporator in the lower region. Considered here is the normal flow direction of the refrigerant where the evaporator operates as evaporator and the condenser operates as condenser. 'Upstream' of the second evaporator portion means that the expansion device is positioned in the refrigerant circuit between the condenser and the second portion of the evaporator.

The expansion device may be a valve, a capillary or an expansion valve which optionally may have an adjustable refrigerant flow rate.

Preferably, the first and/or second portion of the evaporator is formed with pipes, windings of pipes or with microchannels. Microchannels have a better heat exchange efficiency, e.g. less volume of tank and/or a shorter evaporator are required for the same amount of heat exchange. In the case of pipes, the pipes may be arranged in the upper and lower region of the evaporator tank horizontally and/or may be arranged inclined extending from the upper region to the lower region of the tank. In the case of microchannels, the whole microchannel arrangement is preferably arranged obliquely extending from the upper region to the lower region of the tank, when seen the tank in a vertical cross-section in front view of the washing machine. It is also possible to arrange several microchannel arrangements obliquely, but parallel to each other in the tank.

Alternatively, at least one microchannel arrangement may be arranged in the upper and lower region, respectively (i.e. the microchannels are arranged horizontally in different heights to each other). Preferably, the lower microchannel arrangement is more compact then the upper microchannel so that the lower microchannel arrangement fits in the lower portion (with smaller horizontal cross-section area) of the evaporator tank. The microchannels of the upper and lower region may be arranged above each other or may be at least partially horizontally offset to each other.

Optionally the first portion of the evaporator forms a first evaporator block or battery and/or the second portion of the evaporator forms a second evaporator block or battery, wherein preferably the two blocks are connected by an interconnection pipe to each other and/or an exit header of the one block/battery forms the inlet header of the other block/battery.

In case the evaporator is formed by pipes or winding of pipes, the length and/or the heat exchanging surface of the pipes or windings of the evaporator may be different in the upper region and the lower region. The 'length' corresponds to the longitudinal extension of the pipes when the portion of the evaporator is straightened to a line. Preferably, the length and/or the heat exchanging surface of the pipes or windings of the evaporator arranged in the lower region is shorter/smaller than the length and/or the heat exchanging surface of the pipes or windings of the evaporator arranged in the upper region.

Preferably, the evaporator tank comprises ribs and/or seats arranged on a top surface and/or a bottom surface of the evaporator tank for receiving a thermo-insulating material. More preferably the top and/or bottom surfaces are the outer surfaces of the evaporator tank. The thermo-insulating material avoids heat dispersion. In case the compressor is mounted on the top, such material can also dampen vibrations. Preferably, the ribs and/or seats are evenly distributed over the top outer surface and/or bottom outer surface of the tank. The ribs may increase the stability of the evaporator tank/top module and/or may form spaces (seats) for receiving a thermo-insulating material. In particular, the spaces may be formed by intersection of at least three ribs, preferably by the intersection of four ribs forming rectangles.

The evaporator tank preferably comprises an evaporator tank cover. The evaporator tank cover preferably seals the tank tightly such that no liquids and/or gases are able to escape. The evaporator tank cover may also comprise ribs and/or seats on a top surface or a bottom surface, preferably on a surface facing the top wall.

Top Module:

Preferably, the laundry treatment machine further comprises a top module, wherein when the top module is mounted at the laundry treatment machine it is forming part of the cabinet as a top, and wherein more preferably the top module comprises the evaporator tank and the evaporator.

'Module comprises' means that the respective comprised components form part of the top module and are preferably mounted to the top module. The top module may comprise a tray element. A top wall of the washing machine is preferably mounted on top of the tray element. Preferably the top module has on its upper side a working top which for example is the top wall in the shape of a plate. The components of the top module are pre-assembled such that the top module can be assembled as a whole to the upper side of the laundry treatment machine. In an embodiment the evaporator tank together with the evaporator and/or the condenser are arranged at the top of the laundry treatment machine in a pivotable manner. For example, a hinge may be provided such that the evaporator tank and/or the condenser can be pivoted at one side (e.g. at the lower end or at a lateral side of the evaporator tank and/or condenser) so that for mounting and/or maintenance purposes (change of the drum driving belt) the tank and/or condenser can be pivoted to the top e.g. after releasing some mounting and/or snap-fit elements supporting the tank and/or condenser at the machine top or housing frame.

Alternatively, or additionally the condenser and/or evaporator tank are provided as a ready-to-be mounted module mounted at the top or top region of the machine cabinet. Preferably the module is pivotably supported at the machine cabinet or top or cabinet supporting frame.

Condenser / Tube-in-Tube Arrangement:

The condenser may have an elongate longitudinal extension and one or more of the following may be applicable: (a) the condenser is extending along two sides, along three sides or at least three sides of the evaporator tank, (b) the condenser is guided around the evaporator tank covering an arc around the evaporator tank of at least 70°, at least 80°, at least 100° or at least 120°, and (c) the ratio R between the condenser longitudinal extension L to the condenser maximum or average cross extension Q is at least 10, at least 15 or at least 20.

The alternatives (a), (b), and/or (c) are the following and are disclosed herein. The condenser may be combined with (a), or (b), or (c), or (a) and (b), or (a) and (c), or (b) and (c), or (a) and (b) and (c). In this or an analog way all and/or conjunctions mean this single or multiple combinations.

'Longitudinal extension' is the extension when the condenser is straightened to a line and such straightening is 'theoretically' not deteriorating the heat exchanging efficiency of the condenser. The 'extending along sides' preferably means that the condenser extends in a horizontal plane around the evaporator, preferably around the upper region of the evaporator tank. The 'arc around the condenser' is measured from the geometrical 'center' of the evaporator tank. Preferably, the washing liquid is washing liquid circulated from the interior of the tub through the liquid passage (see below). Alternatively or additionally the washing liquid may be water supplied from an external water tap or a mixture of water supplied from the external water tap and a washing agent (e.g. detergent, conditioner, softener and the like).

Preferably at least 80%, 90% or the whole condenser is guided along an outer wall of the evaporator tank - with respect to the length of the condenser which is in heatexchanging contact between the refrigerant passage and the washing liquid passage.

'Guided around' and 'extending along' are to be seen in a perspective perpendicular to extension planes, e.g. in a top view when the top module is in its operational orientation on the laundry treatment machine. 'Extension planes' are filling the respective volumes occupied by the outer dimensions of the curved condenser and evaporator tank and have a 'flat' dimension as compared to the other two dimensions of the evaporator tank and curved condenser.

Preferably, the condenser is guided around at least three sides of the evaporator tank forming an asymmetric spiral shape. 'Asymmetric spiral shape' means that the condenser does not form a curve that runs only around a first point, but a curve where at least two sections of the condenser run around a first and a second points (points of different position). Preferably, the condenser is guided around the evaporator tank and forms another spiral portion next to the evaporator tank. This results in an extended condenser in the top module with a higher heat exchange efficiency. Thus, the required power of compressor is lower.

The condenser may be or may comprise a tube-in-tube arrangement, where a smaller diameter tube is arranged in a larger diameter tube, wherein in particular in the larger diameter tube the refrigerant (or the washing liquid) is flowing around the smaller diameter tube and wherein in the smaller diameter tube the washing liquid (or the refrigerant) is flowing. Alternatively, microchannels are arranged in the larger diameter tube, wherein in particular the refrigerant (or the washing liquid) is flowing in microchannels around the smaller diameter tube and wherein in the smaller diameter tube the washing liquid (or the refrigerant) is flowing.

When the refrigerant is flowing in the larger diameter tube (outer tube), the required cross-section for refrigerant flow is low and at the same time the heat exchanging area is increased as compared to the refrigerant flowing in the inner tube, as the cross-section for the inner tube where the washing liquid flows is high. On the other hand, the washing liquid flow in the smaller diameter inner tube may reduce the risk of clogging as the tube wall surface is minimized (e.g. no outer surface of an inner tube).

The material of the pipes of the condenser and/or evaporator is copper or aluminum, in particular the material of the inner and/or outer pipes of pipe-in-pipe condenser is aluminum or copper. The refrigerant is for example R134a or R290 (propane). If propane is used, then the length of the pipes (and therefore the volume) is reduced for security reasons. E.g. the maximum refrigerant amount in the heat pump system is or is below 350 gr propane.

Preferably the refrigerant and the washing liquids are flowing in opposite directions in the heat-connected tubes (counterflow) resulting in higher heat exchanging efficiency (considering here the normal flow direction of the refrigerant when the condenser operates as condenser). The condenser may be enclosed by a heat insulating layer, specifically in case of a tube-in-tube arrangement. 'Enclosed' means that essential parts of the condenser are heat insulated.

The inner tube of the condenser may have an inner diameter in the range of 10 to 14 mm, 13 to 17 mm, or 16 to 22 mm) and/or may have a wall thickness in the range of 0,7 to 1 mm, 0,9 to 1,5 mm, 1,4 to 2,2 mm or 2 to 2,5 mm. In addition or as an alternative the outer tube of the condenser may have an inner diameter in the range of 15 to 21 mm, 19 to 25 or 22 to 24 mm and/or may have a wall thickness in the range of 0,7 to 1 mm, 0,9 to 1,5 mm, 1,4 to 2,2 mm or 2 to 2,5 mm. In addition or as an alternative, the heat insulation layer around the outer tube may have an outer diameter in the range of 25 to 28 mm, 27 to 32 mm or 30 to 36 mm.

Alternatively or specifically the inner tube may have an inner diameter of 16 mm (or 12, 14, 18 or 20 mm) and/or may have a wall thickness of 1 mm, 1,5 mm, 2 mm or 2,5 mm. In addition or as an alternative the outer tube may have an inner diameter of 20 mm (or 16, 18, 22 or 24 mm) and/or may have a wall thickness of 1 mm, 1,5 mm, 2 mm or 2,5 mm. In addition or as an alternative, the or an insulation layer around the outer tube may have an outer diameter of 32 mm (or 28, 30, 34 or 36 mm).

Compressor: The compressor may be mounted in a bottom region of the cabinet or alternatively at the top of the laundry treatment machine, in particular at the top module. The compressor may be a variable speed compressor with variable refrigerant flow rate. When mounted at the top the compressor motor axis is oriented vertical or parallel to the top surface of the laundry treatment machine. For using interior space optimally, when mounted at the bottom of the cabinet, the compressor motor axis may be in a horizontal plane or may be inclined maximally 15° to the horizontal plane.

In case the laundry treatment machine is a washing machine, the following applies: Preferably the compressor is arranged in a bottom region of the cabinet if the height of the washing machine cabinet is 85 cm. Alternatively, the compressor may also be arranged at the top of a washing machine with a cabinet height of 87 cm.

When compressor is mounted at the top or bottom, the compressor is preferably mounted at the top with screws. A further screw may be used to block (transport lock) the compressor when the laundry treatment machine is transported. Three screws are normally used to block the tub. The compressor is preferably mounted on rubber blocks for dampening vibrations. The compressor weight may be 6 to 7 kg.

In case the laundry treatment machine is a washer dryer, the following applies: Preferably the compressor in a washer dryer is arranged in a bottom region of the cabinet. In practice, the washer dryer is possible with a cabinet height of 85 cm only if the evaporator tank is flat and the counterweight above the tub is removed. Due to the air conduits above the tub in a washer dryer, there may not be enough space for an arrangement of the compressor at the top. In a washer dryer with a cabinet height of 87 cm, there may be enough space for an evaporator tank which is not flat and/or the counterweight may be arranged above the tub.

Circulation Unit

Preferably, the refrigerant flow changing device comprises a refrigerant inlet and a refrigerant outlet and which is adapted in a first switching state to fluidly connect the refrigerant inlet to a first pipe of the refrigerant circuit and the refrigerant outlet to a second pipe of the refrigerant circuit, and in a second switching state to fluidly connect the refrigerant inlet to the second pipe of the refrigerant circuit and the refrigerant outlet to the first pipe of the refrigerant circuit. The refrigerant flow direction may be changed (reverted) by the refrigerant flow changing device (preferably a four-way valve) outside the compressor.

Preferably the refrigerant inlet of the device is connected to the outlet of the compressor and the refrigerant outlet is connected to the inlet of the compressor. The first switching state may be the normal operation state (normal operation mode) for the heat pump where the first pipe is fluidly connected to the condenser inlet and the second switching state may be the operation state for the heat pump which corresponds to the reverse operation mode (first regeneration mode A)) in which the previous evaporator operates as a condenser and the previous condenser operates as a evaporator.

Preferably the reverse operation mode is used for de-icing the evaporator tank at the end of a washing and/or rinsing phase by transferring the residual heat of the washing liquid to the heat exchanging medium in the evaporator tank via the refrigerant and/or if for example the heat transfer to the washing liquid is no longer required or possible (e.g. no circulation, washing liquid maximally heated) then the residual heat of the heat pump may be deposited in the second operation mode in the evaporator tank so that this heat can be extracted in the next washing cycle for heating the circulated liquid.

Preferably, the laundry treatment machine further comprises a washing liquid circulation unit which is adapted to circulate the washing liquid from the tub through the condenser and back to the tub. The circulation unit may comprise a circulation pump (jet pump), a suction line connecting the tub to the inlet of the circulation pump and a return line connecting the outlet of the pump to the tub or to a fluid passage which is connected to the tub. In particular, the inlet of the suction line may be connected to a sump of the tub.

In addition or as an alternative, the outlet of the return line may be connected (a) to a spray nozzle that may be arranged at the tub or at a loading opening of the tub. The spray nozzle may be adapted to spray the circulated washing water towards the drum interior. The spray nozzle may be a shaped pipe where in particular the circulated liquid is released without water pressure. When herein a 'spray' is mentioned, the liquid exiting for example a nozzle may be pressurized (having e.g. a predefined directivity) or may be pressure-free. In particular, the spray nozzle introducing water into the tub is designed to change the shape of the liquid jet, e.g. by enlarging it as a sort of 'V or expanded spray. Or the outlet of the return line is connected (b) to the interior of a detergent drawer housing of the laundry treatment machine from where the circulated washing water may be guided back to drum interior. Or the outlet of the return line is connected (c) to a manifold of the laundry treatment machine which may be fluidly connected to the interior of the tub or the outlet of the return line is connected first to the drawer housing and then to the manifold. Preferably, a portion of the return line forms the liquid passage of the condenser.

The laundry treatment machine may be a washing machine or a washer-dryer having the normal operation mode of the heat pump in which during at least a portion of a washing cycle the circulated washing liquid is heated, and/or having the reverse operation mode of the heat pump (regeneration mode A)) in which during at least a portion of a washing cycle the circulated (washing) liquid is cooled. In such a washing machine or washerdryer and during the reverse operation mode (regeneration mode A)) cooling the washing liquid is used for de-icing the evaporator in e.g. the last washing cycle and/or during at least one rinsing phase.

Preferably, the washing liquid circulation through the washing liquid circulation unit and the first regeneration mode A) (reverse operation mode of the heat pump) are executed at least partially simultaneously. Warm washing water is circulated through the condenser and thereby, during regeneration mode A), the refrigerant flowing through the condenser is heated up such that the washing liquid within the evaporator tank is heated by the refrigerant flowing through the evaporator. Therefore, ice in the evaporator tank can melt.

The manifold may for example be connected to the outlet of the drawer housing receiving therefrom a mixture of water and powdered or liquid washing agents. In addition or as an alternative the manifold may be connected to a tap water supply valve.

The circulation unit is effective in saving water when it resupplies the water circulated from the tub into drum (see below spray nozzle) as the water amount to be stored in tub is less as it is not required that the lower diameter of the drum is immersed in washing water having a respective water level.

The resupply via a spray nozzle (a) may be the most efficient use of detergent and water. This is a preferred solution for resupply of heated washing liquid for a washing machine. Preferably the spray nozzle is arranged at a bellows flexibly sealing between the loading opening (or porthole door) in the cabinet and the front side of the tub. In addition or as an alternative the spray nozzle may be arranged at an upper position with respect to the bellows or front opening in the tub. In addition or as an alternative the spray direction at the spray nozzle exit may be directed axially towards the rear side of the drum.

The suction line may be completely arranged in a bottom region of the cabinet. In addition or as an alternative the suction line may be located completely below the tub. The suction line is e.g. the shortest connection between circulation pump and the inlet to the condenser.

Preferably the laundry treatment machine further comprises a washing liquid directing device (e.g. flow diverter) adapted to direct the flow of circulated washing liquid that has passed the condenser selectively through a first return passage to the tub or through a second return passage to the tub. The first return passage may be the spray nozzle (a) and/or the first return passage may be selected and thus used during the first operation mode (washing cycle). The second return passage may include a passage through the interior of the drawer housing (b) and/or the manifold (c).

The directing device may be a switching and/or valve element. As an alternative, the directing device may be a flow diverter which depending on the flow speed of the circulated washing liquid directs the circulated washing liquid into

- a first outlet towards the first return passage (e.g. at a higher flow rate and/or to the spray nozzle (a)), or

- a second outlet towards the second return passage (e.g. at a lower flow rate and/or to the drawer housing (b), the manifold (c) and/or the spray nozzle.

Preferably the washing liquid directing device is arranged downstream the detergent drawer housing.

Preferably, the return line is forming a siphon between the exit at the condenser outlet of the liquid passage and the outlet of the return line. Specifically, when the outlet of the return line is at the spray nozzle (a) (e.g. at an upper portion of the gasket at the loading opening).

Tray Element:

Preferably the top module comprises a tray element which provides a supporting structure of the top module, wherein the evaporator tank is integrated in the tray element. Preferably the tray element has one, two, three or four peripheral outer sides (side walls) that preferably extend downward from an upper plane of the tray element and/or form lateral side surfaces of the tray element.

Preferably the condenser is guided along the lateral outer wall of the evaporator tank along at least two sides of the evaporator tank and/or along an arc of at least 180° around the evaporator tank, and wherein the condenser is at least partially received in or at a receptacle along the path around the evaporator tank. Alternatively or additionally the condenser is guided along the peripheral outer sides of the tray element, namely along two, three or four peripheral outer sides. Preferably the condenser is arranged within the footprint (when seen from above in operational orientation) of the tray element. Preferably the tray element has lateral outer side walls at two, three or four sides and optionally the condenser is arranged at a vertical level to be located behind the sides of the tray level (when seen in side view).

By providing the condenser in an extended longitudinal shape the heat exchanging efficiency along the extended longitudinal shape is optimized while at the same time the overall volume of the condenser is reduced.

When 'winding' the condenser around the evaporator tank and/or along the periphery of the tray element the length of the extended condenser is stored within the tray element while the curvature of bending is reduced as compared e.g. to the bending into a spiral form.

Preferably, the outer lateral wall of the evaporator tank forms part of the receptacle for the condenser. The evaporator tank may be part of the receptacle and may stabilize/support the condenser. In addition or alternatively, the receptacle is only formed by lateral walls of the tray element. Additionally or alternatively the outer peripheral walls (see above) of the tray element form part of the receptacle for the condenser. Preferably at least at one, two, three or four sides of the tray element the condenser is received between the outer peripheral wall of the tray element and the outer lateral wall of the evaporator tank.

'Integrated in' means both that the evaporator tank may be formed as a single/ unitary element with the tray element (in a single piece construction) or as a separate element mounted to the tray element. Formed as a separate element, the evaporator tank may be formed in a single piece or may comprise several elements which are assembled, e.g. the bottom part of the evaporator tank and side walls. The ceiling part of the evaporator may be a cover, in particular a removable or non-removable evaporator tank cover for sealing the tank. E.g. the elements (evaporator tank and/or tray element) are monolithically formed elements produced for example by injection (plastic) molding or by deep drawing of a metal/plastic sheet.

Preferably, the flow changing device is mounted at or on the tray element, wherein the flow changing device is adapted to switch the refrigerant flow in the heat pump circuit between the normal operation mode of the heat pump (i.e. forward refrigerant flow direction) and the reverse operation mode of the heat pump (i.e. reversed/inverted refrigerant flow direction).

Preferably the evaporator tank has an upper bottom region which is located at a higher vertical level (e.g. forming the bottom of the upper region) than a lower bottom region which is located at the lowest vertical level (e.g. forming the bottom of the lower region), wherein in particular the lower bottom region is located at a side region of the tray element while the upper bottom region is located more centrally of the tray element when seen from above. Preferably the (left or right) side region and the center region relate to a perspective when seen in front view or rear view (in relation to an operational position of the top module mounted to a laundry treatment machine).

The tray element may comprise fixing and/or sealing elements for fixing and/or sealing a cover over the evaporator tank.

The receptacle (recess) preferably comprises one or a plurality of alignment and/or clamping elements for positioning and/or clamping the condenser within the receptacle or within the tray element. This stabilizes the condenser in its predefined position and form and/or secures the condenser to the tray element during manufacturing process and operation.

Preferably, the tray element has lateral outer walls on at least three sides thereof. This increases stability of the tray element and top module. The outer lateral walls of tray element preferably form outer lateral/peripheral walls of top module. The outer lateral walls of tray element may form part of the receptacle for receiving the condenser. Preferably, the receptacle (recess) has the shape or substantially the shape of the condenser when mounted at the top module. The outer lateral walls laterally protect condenser also during assembling process. More preferably the receptacle is formed by the outer lateral walls of the tray element and the outer walls of the evaporator tank. Preferably, the evaporator, the condenser, the expansion device and all the refrigerant pipe connections are mounted in or on the top module, preferably in or on the tray element. In addition, the compressor may be mounted in or on the top module and/or tray element.

Preferably, the tray element comprises a mounting bracket mounted to the tray element or being integral part of the tray element, wherein the mounting bracket is adapted to mount thereon the compressor of the heat pump.

According to claim 8, a laundry treatment machine, in particular a washing machine or a washer dryer, is provided. The laundry treatment machine comprises: a cabinet housing a tub and a drum rotatably arranged in the tub for washing laundry therein, a heat pump having a compressor, an evaporator and a condenser, the condenser being adapted to heat washing liquid, an evaporator tank housing the evaporator or at least a portion of the evaporator, wherein the evaporator tank is a tank for storing a heat exchanging medium, a regeneration unit adapted to circulate the washing liquid with a regeneration pump from the tub or sump through or along the evaporator tank and back to the tub, in particular a sump, or a filter arranged upstream of the regeneration pump, and a refrigerant flow changing device adapted to change between a normal operation mode of the heat pump and a reverse operation mode of the heat pump. In the normal operation mode of the heat pump, the condenser is adapted to heat the washing liquid and the evaporator is adapted to cool the heat exchanging medium, and in the reverse operation mode of the heat pump, the condenser is adapted to cool the washing liquid and the evaporator is adapted to heat the heat exchanging medium.

Preferably, the laundry treatment machine further has a control unit and the control unit is adapted to control the machine in a first regeneration mode A) and in a second regeneration mode B), wherein in the first regeneration mode A) the heat pump is in the reverse operation mode, and wherein in the second regeneration mode B) the regeneration unit is circulating the washing liquid.

Preferably, the control unit is adapted to control the machine during a laundry treatment cycle such as to apply the first regeneration mode A) and the second regeneration mode B) at least partially simultaneously, and/or at least partially exclusively in the first and/or in the second regeneration mode A) or B). The regeneration modes A) and B) may be applied one after the other in the exclusive operation mode.

Preferably, the laundry treatment machine further comprises a heater arranged within the tub for heating the washing liquid. The heater may be used for alternatively heating the washing liquid if the heat pump system does not work or for supporting the heat pump. Preferably the heater is used if the desired temperature of the washing liquid is higher than can be achieved by only using the heat pump system for heating the washing liquid. E.g. if the desired temperature of the washing liquid is higher than 60, 65, 70 or 75 °C, then the heater is used. E.g. to heat up the washing liquid pre-heated by the condenser of the heat pump to the predetermined temperature being higher than the maximum condenser heating temperature.

Preferably, the machine further comprises an external evaporator, in particular an airheated evaporator, arranged at an inlet of the compressor for heating the refrigerant of the heat pump. The inlet refers to the refrigerant inlet at the compressor in the normal operation mode of the heat pump. Preferably the external evaporator is an air-heated evaporator in which ambient air is used for heating the refrigerant.

In normal operation mode and in reverse operation mode of the heat pump, the external evaporator heats up the refrigerant.

In normal operation mode of the heat pump, the refrigerant is heated by the external evaporator and the washing liquid within the tub is heated via the heat exchange at the condenser.

In the reverse mode of the heat pump (regeneration mode A)), external evaporator heats refrigerant, wherein the heat of the refrigerant is then transferred to the washing liquid in the evaporator tank (evaporator in evaporator tank works as condenser during regeneration mode A)).

In regeneration mode B), washing liquid drained from the tub is circulated through the evaporator tank. In normal operation mode of the heat pump, the external evaporator further heats the refrigerant heating the washing liquid within the tub, wherein the heated washing liquid within the tub is circulated through the evaporator tank during regeneration mode B).

Thus the heating of the evaporator tank during regeneration modes A) and/or B) and thus the melting of ice is improved by operation of the external evaporator. When the refrigerant flow changing device changes from the normal operation mode of the heat pump to the reverse operation mode of the heat pump, the role of the evaporator and the condenser is reversed, but the external evaporator preferably remains working as an evaporator. Thus, the operation of the external evaporator is preferably independent of the operation mode of the heat pump.

By providing the external evaporator, the dimension of the evaporator within the evaporator tank may be reduced so as to better use the heat available from the liquid in which it is immersed, and the formation of ice is reduced/made slower in time. The need for evaporating the refrigerant may then be compensated by operation of the external evaporator.

Preferably, the laundry treatment machine further comprises a cooling path adapted to route cool air from the external evaporator along the compressor of the heat pump.

The ambient air flowing through the external evaporator exchanges its heat with the refrigerant of the heat pump. Thereby, the air of the external evaporator cools, wherein the cool air exits the external evaporator through the cooling path. The cool air flowing along the compressor extracts the heat from the compressor. The air heated up by the compressor is preferably routed out of the laundry treatment machine. Since the air exiting the laundry treatment machine is heated up, the room in which the machine is placed is not cooled by the operation of the external evaporator. This avoids any disturbance for the user.

Preferably, the laundry treatment machine further comprises a condensate collector arranged below the external evaporator and being adapted to collect condensate formed on and dripped down from the external evaporator. Thereby, the condensate is collected and it is prevented from falling onto components, in particular electrical components as e.g. the compressor, inside the laundry treatment machine.

The condensate collector may comprise a drain outlet to drain the condensate collected within the condensate collector. Preferably the drain outlet is positioned at the lowest level of the bottom surface of the condensate collector. The drain outlet automatically empties the condensate collector, which makes it more convenient for the user. It is not necessary for the user to manually empty the condensate collector. Preferably a draining pipe fluidly connects the drain outlet with the tub or the sump. From the tub or the sump, the condensate is preferably drained out of the washing machine by a drain pump. A filter or the filter as described above may be arranged upstream of the drain pump. Alternatively, the drain outlet of the condensate collector is directly connected to the filter or the drain pump for draining the condensate.

Each individual feature of the treatment machine and/or the top module can be combined with the method, or any sub-group of features (e.g. any of the dependent claims) of the treatment machine and/or top module (e.g. tray element) can be individually combined with the method. Vice versa any individual (functional) feature or sub-group of (functional) features of the method can be combined with the treatment machine and/or the top module (e.g. tray element) as a functional feature of the machine.

Any feature disclosed herein (for the above embodiments and/or configurations and from the below described detailed embodiments and modifications) can be combined with the claimed subject individually or in any sub -combination. If herein the conjunction "and/or" is used all logical elements and combinations are individually disclosed. E.g. a, b and/or c discloses the elements/combinations a, b, c, ab, ac, be as well as abc.

Reference is made in detail to preferred embodiments of the invention, examples of which are illustrated in the accompanying figures, which show:

Fig. 1 a perspective view of another washing machine with a top module,

Fig. 2 an exploded view of the washing machine of Fig. 1 without the front and top wall,

Fig. 3 a detailed perspective view of the pump arrangement of Fig. 1,

Fig. 4 a front view of the upper portion of the washing machine of Fig. 1 without the front wall,

Fig. 5 an exploded view of the top module and the compressor of Fig. 2, Fig. 6 an exploded view of the top module and the compressor of Fig. 2 in another perspective view,

Fig. 7 a perspective view of the top module and the evaporator of Fig. 2 with partial section of the tray element,

Fig. 8 a perspective view of the washing machine of Fig. 1 without the front and top wall and with another configuration of the circulation pump,

Fig. 9 a detailed perspective view of the pump arrangement of Fig. 8,

Fig. 10 a front view of the washing machine of Fig. 8,

Fig. 11 a perspective view of the washing machine of Fig. 8 without the side walls and the rear wall and with an evaporator tank water regeneration unit,

Fig. 12 a detailed perspective view of the pump arrangement of Fig. 11,

Fig. 13 a perspective view of the compressor, the pump arrangement and the top module of the washing machine of Fig. 11 without the evaporator tank water regeneration unit and another arrangement of the jet pump,

Fig. 14 a perspective view of the washing machine of Fig. 11 without the evaporator tank water regeneration unit and with another configuration of the jet pump and the condenser,

Fig. 15 a perspective view of the washing machine of Fig. 14 with another arrangement of the condenser and a switching valve,

Fig. 16 an exploded view of the compressor, the pump arrangement and the top module of Fig. 11,

Fig. 17 a perspective view of the washing machine of Fig. 16 in an assembled state without the front wall, rear wall and side walls and with an evaporator tank water regeneration unit, Fig. 18 a perspective view of the washing machine of Fig. 17 with another configuration of the evaporator tank water regeneration unit,

Fig. 19 a perspective view of Fig. 16 with another configuration of the tray element,

Fig. 20 a detailed sectional view of the evaporator tank inlet and outlet portion,

Fig. 21 a schematic diagram of the heating and cooling process during circulation of the washing liquid in a washing machine,

Fig. 22 schematic block diagram of a control unit and its input and output signals,

Fig. 23 different implementations of regeneration modes in main wash and rinsing phases, and

Fig. 24 the coefficient of performance (COP) when the evaporator tank is regenerated via regeneration mode A) in the last part of the main wash.

Fig. 1 is a perspective view of the outer appearance of a washing machine 2 with a top module 5. The washing machine 2 has a cabinet 4 comprising two side walls 10, a front wall 8, a bottom (plate or shell) 56 (see: Fig. 2), a rear wall 24 (see also: Fig. 2) and a top wall 9. The top may be formed by the top module 5 which may be mounted on the cabinet 4 by fastener elements, e.g. by screws or snap-in elements. A top wall 9 may be arranged on top of the washing machine 2, in particular on top of the top module 5 and is preferably forming a work top.

At the front wall 8 a loading opening 16 which is closed by a door 18 is provided for loading laundry into the washing machine 2. The upper region of the machine front face comprises a detergent drawer 12 with a handle 13 which is preferably arranged at the left side of the upper region. The detergent drawer 12 is used for storing and in particular for providing washing agents (e.g. detergent, softener, conditioner, auto dosing or other treatment agents) during washing cycles. The washing machine 2 further has a control panel 14 preferably arranged at the middle and/or right side of the upper region of the machine front face. The control panel 14 preferably comprises a display for displaying information about the washing program (e.g. energy consumption, duration of the washing cycle and the like) and an input device. In this case, the input device is a control knob provided for selecting between different washing programs. The knob is preferably arranged between the control panel 14 and the detergent drawer 12.

The front wall 8 may comprise an air inlet opening (not shown) which may be arranged near the center. A cover for service opening 22a may be provided at the front wall 8 e.g. on the right side of the lower region of the front wall 8. The air inlet opening enables air entering the interior of the washing machine 2. The air passing through the inlet opening may be provided for cooling the compressor and further electronic components inside the washing machine 2 with air.

The washing machine 2 shown in Fig. 1 is a front- loading machine having preferably a horizontal drum rotation axis, but in alternative embodiments the drum may be inclined relative to the horizontal and vertical directions.

A refrigerant flow direction 94 and a washing liquid flow direction 96 are indicated by arrows in some of the following Figures (see: Figs. 5 and 16). Therefore, a dashed arrow defines the washing liquid flow direction 96 and a filled arrow the refrigerant flow direction 96. These definitions for the flow directions are valid for the Figures herein.

Fig. 2 is an exploded view of the washing machine of Fig. 1 without the front and top wall 8, 9. Fig. 3 is a detailed perspective view of the pump arrangement of Fig. 2 and Fig. 4 is a front view of the upper portion of the washing machine of Fig. 2 without the front wall.

As shown in Fig. 2, a tub 58 and a drum 60 rotatably arranged in the tub 58 and in which laundry is received, are arranged inside the cabinet 4. The tub 58 may be suspended by spring dampers 30 and/or a balance weight 28 may be provided for stabilizing the tub 58 and the drum 60 (see Fig. 4). For preventing water from entering the washing machine 2, except the tub 58 and drum 60, a bellow 62 may be mounted to the tub 58 or to the tub 58 and to the front wall 8 (not shown). Further, a detergent drawer housing 12a for receiving the drawer 12 is arranged in the upper region of the washing machine 2. The detergent drawer housing 12a is preferably arranged on the left side of the upper region of the washing machine 2, in particular below the top module 5. The detergent drawer 12 is inserted into the detergent drawer housing 12a. A water supply unit (not shown) connected to the detergent drawer housing 12a may provide fresh water from the outside of the washing machine 2 to flush the detergent from the detergent drawer 12 through the water supply and the water inlet 65 into the tub 58.

A drum drive arrangement (not shown) may comprise a motor for driving the drum 60 and optionally a torque transmission element (e.g. a belt) connecting the motor and the drum 60 for driving the drum 60. The motor may be arranged at the rotation axis of the drum 60 or may be arranged under the rear region of the tub 58. The drum drive arrangement is applicable for all embodiments of washing machines disclosed herein. Alternatively a drum drive motor is mounted on the backside of the tub (not shown).

As further shown in Fig. 2, the washing liquid supplied to a tub 58 of the washing machine 2 is circulated by and through a washing liquid circulation unit 64 to save water and energy. In the washing liquid circulation unit 64, the washing liquid is guided through a first, second, third and fourth water circulation sections 64a, 64b, 64c, 64d. The first water circulation section 64a connects the tub outlet (not shown, e.g. at the sump of the tub 58) to a circulation pump 66. The circulation pump 66 is preferably arranged in the bottom region, e.g. at the lower right comer at the front of the washing machine 2. The second water circulation section 64b extends between an outlet of the circulation pump 66 and a washing liquid condenser inlet 82, the third water circulation section 64c extends between the washing liquid condenser inlet 82 and a washing liquid condenser outlet 84 (within the condenser inner tube 118, see: Fig. 20), and the fourth water circulation section 64d connects the washing liquid condenser outlet 84 to the tub 58 via a nozzle 65. As shown in Fig. 2, at least a portion of the second water circulation section 64b may extend along a side wall or a comer of the washing machine 2, e.g. at the left side of the washing machine 2 parallel to the side wall 10.

A condenser 81 comprises the washing liquid condenser inlet 82 and outlet 84 and a refrigerant condenser inlet 86 and outlet 88. The condenser 81 is used for heating the washing liquid within the washing liquid circulation unit 64. The washing liquid is circulated in the washing liquid circulation unit 64 through the water circulation sections during a washing cycle and is heated by the heated refrigerant when passing the condenser 81.

The condenser 81 may be a tube-in-tube condenser consisting of an inner tube 118 for guiding the washing liquid, an outer tube 120 for guiding the refrigerant and an insulation layer 122 (see Fig. 20) when starting from the inside of the condenser 81. The flow direction of the refrigerant and the washing liquid within the condenser 81 may be opposite to each other for improving the heat exchange. The condenser 81 further comprises the washing liquid condenser inlet 82 and the refrigerant outlet 88. Preferably, a connection element comprising the refrigerant outlet 88 is provided at the water inlet portion of the condenser 81 and which is adapted to guide refrigerant through the outer tube 120. More preferably, an inner surface of a first end portion of the connection element is connected to the outer surface of the inner tube 118 of the condenser and an inner surface of a second portion of the connection element is connected to the outer surface of the outer tube 120 of the condenser.

The washing liquid condenser outlet 84 and the refrigerant condenser inlet 86 are preferably designed as the washing liquid condenser inlet 82 and the refrigerant condenser outlet 88. Alternatively to this condenser configuration the washing liquid may flow in the outer tube 120 of the condenser and the refrigerant may flow in the inner tube 118 of the condenser.

The circulation pump 66 is preferably arranged in the bottom region of the washing machine 2, e.g. in the lower left corner at the front of the washing machine 2. The circulation pump 66 is used to suck in washing liquid (during a washing phase) or water (during a rinsing phase) from the sump of the tub 58, in particular from the drain manifold which is arranged at the lower part of the sump 140 and to recirculate the liquid to the upper part of the tub 58 where the liquid is introduced into the tub 58 by the water inlet (e.g. nozzle) 65.

As shown in Fig. 3, the washing machine 2 further comprises a drain pump 72. The drain pump 72, which is connected to a tub outlet (e.g. via the sump, in particular from the drain manifold which is arranged at the lower part of the sump 140) may be connected to a water drain 70 which is used for draining the washing liquid at the end of a washing cycle out of the washing machine 2. Herein 'washing liquid' comprises water with resolved treatment agent, water used e.g. for rinsing and other liquids used during a washing, laundry treatment and/or drying cycle. The drain pump 72 is preferably arranged in the bottom region of the washing machine, e.g. in the lower right corner at the front of the washing machine 2.

As shown in Figs. 2 and 3, the washing machine 2 may have a mixing pump 76 which may be connected to the tub outlet, and which sucks in water and detergent from the bottom of the tub (e.g. the sump of the tub 58, in particular from the drain manifold which is arranged at the lower part of the sump) at the beginning of a washing cycle after detergent has been introduced into the tub 58 and re-send the water and detergent to the tub 58, e.g. to the sump of the tub or in particular to the tub 58 below a water heater (not shown), by a return line 77. Thereby, the mixture and dissolution of the detergent in the water can be improved and accelerated. The mixing pump 76 is preferably arranged in the bottom region of the washing machine, e.g. in the lower right corner at the front of the washing machine 2. Preferably, at least two of the drain pump 72, the circulation pump 66 and the mixing pump 76 are integrated in a pump group. Preferably a filter of a filter opening 68 is provided upstream of the mixing and drain circuit.

As shown in Fig. 2 and in particular in Fig. 5, the heat pump comprises a compressor 36, an evaporator 102 and a condenser 81 which are preferably arranged at the inside of the washing machine 2. The compressor 36 is preferably arranged in the bottom region, e.g. at the lower left comer at the front of the washing machine 2. Preferably, the compressor 36 is mounted on at least one damping element 92.

Fig. 5 is an exploded view of the top module and the compressor of Fig. 2 and Fig. 6 is an exploded view of the top module and the compressor of Fig. 2 in another perspective view. A refrigerant circulation circuit 42 comprises a first, second, third, fourth, fifth and sixth refrigerant circuit section. The first refrigerant circuit section 44D extends between the refrigerant condenser outlet 88 and the evaporator inlet 104, the second refrigerant circuit section 46D between the evaporator outlet 106 and the first inlet of the switching valve 78 (refrigerant flow changing device), the third refrigerant circuit section 48D between the first outlet of the switching valve 78 and the compressor inlet 110, the fourth refrigerant circuit section 50D between the compressor outlet 112 (see Fig. 6) and the second inlet of the switching valve 78, the fifth refrigerant circuit section 52D between the second outlet of the switching valve 78 and the refrigerant condenser inlet 86, and the sixth refrigerant circuit section 54 (see: Fig. 20) between the refrigerant condenser inlet 86 and outlet 88 which in this example are the inlet and outlet of an outer tube of the condenser (see Fig. 20). The first refrigerant circuit section 44D may comprise an expansion device 40 (e.g. a capillary as shown in Fig. 36) for controlling the amount of refrigerant released into the evaporator 102.

The switching valve 78 may be arranged below the condenser 81, preferably between a drawer housing 12a and the rear wall 24 of the washing machine 2. Most preferably, the longitudinal axis of the switching valve 78 extends vertically (in an operational position of the washing machine (see Fig. 2).

As shown in Figs. 2 and 5, the top module 5 may comprise a tray element 6 which is mounted on the top of the washing machine 2, and which is preferably mechanically connected to the two side walls 10, the front wall 8 and/or the rear wall 24 of the washing machine 2. As shown in Fig. 7 the tray element 6 preferably has lateral side walls 7 along the periphery of the tray element and/or downward from an upper plane/plate of the tray element. As shown in Fig. 2, the top module 5 comprises the condenser 81 and the evaporator 102. Further, the tray element 6 comprises an evaporator tank 100 which may be arranged on only one side of the entire tray element 6. The evaporator tank 100 comprises the evaporator 102 and may form with an evaporator tank cover 32 a closed tank for permanently storing a heat exchanging medium. The evaporator 102 is surrounded by (immersed in) the heat exchanging medium stored in the evaporator tank 100 for exchanging heat between the refrigerant flowing through the evaporator 102 and the heat exchanging medium. The evaporator inlet 104 and outlet 106 may be arranged at the bottom of the evaporator tank 100, e.g. near the front wall 8 of the washing machine 2.

Preferably, the tank 100 is arranged on the right side of the tray element 6 when seen the washing machine in front view. The switching valve 78 may be arranged between the top module 5 and the drawer housing 12a. Preferably, the switching valve 78 and/or at least portions of the refrigerant circuit sections may be arranged in the remaining portion of the tray element 6, next to the evaporator tank 100. Preferably, the switching valve 78 is arranged vertically, more preferably the longitudinal axis of valve 78 is parallel to the front/rear wall of the washing machine 2. The tray element 6 may further comprise a maintenance opening 128, preferably with a rectangular shape, arranged above the switching valve and/or the refrigerant circuit sections.

Preferably, the evaporator tank 100 and the tray element 6 are formed in a single piece, for example by injection molding of plastic or by deep drawing of a metal sheet. The evaporator tank 100 is preferably covered by the evaporator tank cover 32. Preferably, a gasket is arranged between the evaporator tank cover 32 and the evaporator tank 100. The evaporator tank cover 32 may be mounted to the evaporator tank 100 or the tray element 6 detachable e.g. by screws or non-detachable e.g. by welding or gluing. The evaporator tank cover 32 may comprise seats and/or ribs 34 at the outer side for receiving a thermo-insulating material. As shown in Fig. 5, the evaporator inlet and/or outlet 104, 106 may be arranged on a side wall of the evaporator tank 100, preferably on the rear side wall when looking to the washing machine in front view. Alternatively, the evaporator inlet and/or outlet 104, 106 may be arranged at the bottom of the evaporator tank 100. The evaporator tank 100 may comprise mounting elements 108 and/or the side facing the evaporator tank 100 of an evaporator tank cover 32 may comprise fixing elements 138, each for fixing the evaporator 102 when arranged within the tank 100.

The third and fourth refrigerant circuit section 48D, 50D which preferably extend between the top and the bottom of the washing machine 2 are preferably flexible pipes. The piping of the remaining refrigerant circuit sections 44D, 46D, 52D - except the piping of the heat exchanger(s) itself, may also be provided as flexible pipes. The flexible pipes may be easily adapted to paths which are not straight without requiring mechanical bending. A large part of the third and fourth refrigerant circuit sections 48D, 50D may extend between the bottom region and the top region of the washing machine 2 where the top module 5 is arranged. The third and fourth circuit sections 48D, 50D may run along at the left side of the washing machine 2 from bottom to top parallel to the side wall 10 (see: Fig. 2). The switching valve 78 may be arranged next to the evaporator tank 100 for receiving a heat exchanging medium (e.g. water), preferably on the left side of the evaporator tank 100 when seen the washing machine 2 in a front view. The valve 78 may be arranged in a horizontal, but preferably vertical position as shown in Fig. 2.

Fig. 7 shows a perspective view of the top module and the evaporator of Fig. 2 with partial section of the tray element 6. The tray element 6 may comprise a recess provided on an underside of the tray element 6 (a surface of the tray element 6 facing the tub 58 of the washing machine when mounted) that may form a channel extending along at least one side of the evaporator tank 100. The channel preferably has the shape of the condenser 81, for receiving the condenser 81 when mounted on top of the washing machine 2. The condenser 81 is guided at least partially around the evaporator 102, preferably extending along one side, two sides, three sides or four sides of the evaporator tank 100.

Preferably, the condenser 81 is guided along the inner side of peripheral side walls 7 of the tray element. Preferably the side walls 7 form part of a receptacle for receiving the condenser 81 thereby protecting and/or supporting the condenser within the tray element (top module) during assembling. Further preferred the condenser is arranged at a vertical level (in operational orientation) between the evaporator tank and the peripheral side walls 7 - at least along sides of evaporator tank where no further components of the tray element are arranged. E.g. the condenser 81 is positioned between the peripheral side walls 7 and the outer lateral wall of the evaporator tank 100 at one, two or three sides of the evaporator tank.

Fig. 8 is a perspective view of the washing machine of Fig. 1 without the front and top wall and with another configuration of the circulation pump. Fig. 9 is a detailed perspective view of the pump arrangement of Fig. 8 and Fig. 10 is a front view of the washing machine of Fig. 8. The basic design of the washing machine of Figs. 8 to 10 may be identical to the washing machine of Fig. 2. Therefore, only the differences between both washing machines 2 are outlined in the following. Otherwise, the elements and functions as described above with respect to the other elements of the washing machine of Fig. 2 correspondingly also apply individually, in subgroups or as a functional group to the embodiment of Figs. 8 to 10.

The circulation pump (jet pump) 66 may be arranged below the tub 58, in particular the circulation pump 66 is fixed to the tub 58 from below (difference to the circulation pump of Fig. 2 which is arranged at the bottom right comer of the washing machine). A first water circulation section 64a* connects the tub outlet to the circulation pump 66. In particular, a first portion of the first water circulation section 64a* is connected to the filter opening 68 and a second portion of the first water circulation section 64a* connects the filter opening 68 with the circulation pump 66 (see: Fig. 9). As shown in Fig. 10, a second water circulation section 64b* connects the circulation pump outlet with the washing liquid condenser inlet (not shown, cf. Fig. 2).

Fig. 11 is a perspective view of the washing machine of Fig. 8 without the side walls and the rear wall and with an evaporator tank water regeneration unit. Fig. 12 is a detailed perspective view of the pump arrangement of Fig. 11 and Fig. 16 is an exploded view of the compressor, the pump arrangement and the top module of Fig. 11. The basic design of the washing machine of Figs. 11 to 16 may be identical to the washing machine of Figs. 8 to 10. Therefore, only the differences between both washing machines 2 are outlined in the following. Otherwise, the elements and functions as described above with respect to the other elements of the washing machine of Figs. 8 to 10 correspondingly also apply individually, in subgroups or as a functional group to the embodiment of Figs. 11 to 16. As shown in Figs. 11, 12 and 16, the mixing pump 76 (regeneration pump) is the same mixing pump as described with respect to the other Figures, but the mixing pump may have another function. In particular, the regeneration pump 76 may be used for sucking washing liquid from the tub 58 and conveying the washing liquid through the evaporator tank 100 (instead of using the mixing pump 76 for draining washing liquid from the tub and re-introducing the washing liquid via the return line 77 into the tub 58 as shown e.g. in Figs. 8 to 10 and 13 to 15). In this embodiment, the evaporator tank 100 is a flow-through tank. Alternatively, instead of changing the function of the mixing pump 76, a further regeneration pump may be provided for sucking liquid from the tub 58 and conveying the washing liquid through the evaporator tank 100 in addition to the mixing pump 76 for draining washing liquid from the tub 58 and re-introducing the washing liquid into the tub 58.

The water exiting the evaporator tank 100 may be guided directly into the tub 58 or sump fluidly connected to the tub 58 or another fluid line fluidly connected to the tub 58 (e.g. detergent housing). Alternatively, the washing liquid is drained by the drain pump (not shown). Preferably, the filter 68 is provided downstream of the tub 58, most preferably in the passage from the tub to the drain pump 72 (shown in Fig. 47). The circulation of liquid from the tub through the evaporator tank serves for (accelerating the) melting the frozen liquid in the tank. Thereby in the next washing and/or drying cycle the heat exchanging medium stored in the evaporator tank (here the liquid previously recirculated) has a higher internal heat that may be reused in the next cycle.

The regeneration pump 76 may be arranged in a bottom region of the washing machine 2, preferably in the lower right comer at the front of the washing machine 2. The washing machine 2 may also comprise a drain pump (not shown) for draining the washing liquid by the water drain 70. Preferably, the drain pump (not shown) and the regeneration pump 76 are integrated in a pump group (see: Fig. 12). The drain pump 72 and the mixing pump 76 may be operated simultaneously or intermittently. In particular, the regeneration pump 76 may suck warm water from the tub 58 and convey the warm water through the evaporator tank 100. While conveying the washing liquid through the evaporator tank 100, the warm liquid cools by exchanging heat with the evaporator 102 in the evaporator tank 100 (i.e. melting of ice formed in the evaporator tank 100). The washing liquid sucked from the tub 58 forms the heat exchanging medium. The drain pump 70 may drain the cold water coming back from the evaporator tank 100 and the mixing pump (regeneration pump) 76 may suck new warm water from the tub of the washing machine. Thus, the water circulating through the evaporator tank 100 is preferably not always the same but it is renewed with hot water sucked by the mixing pump from the tub. The mixing pump 76 may comprise a first water regeneration line 132a which guides the circulated liquid from the mixing pump 76 to the evaporator tank 100 in the tray element 6 of the top module 5 through an evaporator tank inlet 130a. A second water regeneration line 132b may guide the circulated liquid in the evaporator tank 100 from an evaporator tank outlet 130b to the filter 68 at the bottom of the machine. From the filter 68, the liquid may be drained at least partially by the drain pump 70, wherein in particular new warm liquid from the tub may be sucked such that the liquid exiting the evaporator tank 100 is mixed at the filter 68 with fresh warm liquid from the tub. Alternatively, line 132b is fluidly connected to the inside of the tub to return the liquid from the evaporator tank 100 into the tub and from there to the inlet of mixing pump 76 (see e.g. Fig. 18).

As shown in Fig. 11, at least a portion of the first and/or second water regeneration line 132a, 132b may extend along a side wall or a corner of the washing machine 2, e.g. at the right side of the washing machine 2 parallel to the side wall 10 (not shown). The evaporator tank inlet and/or outlet 130a, 130b may be arranged at the bottom of the evaporator tank 100, preferably at the in the lower right comer at the front of the evaporator tank 100.

As shown in Fig. 11, the switching valve 78 is arranged horizontally, more preferably the longitudinal axis of valve 78 is parallel to the front/rear wall of the washing machine 2.

In the following Figs. 13 to 15 are described. Here only the differences between the washing machine according to Figs. 13 to 15 and the washing machine 2 of Figs. 11, 12 and 16 are outlined in the following. Otherwise, the elements and functions as described above with respect to the other elements correspondingly also apply individually, in subgroups or as a functional group to the embodiments of Fig. 13 to 15.

Fig. 13 is a perspective view of the compressor, the pump arrangement and the top module of the washing machine of Fig. 11 and 12 and 16 without the evaporator tank water regeneration unit and another arrangement of the jet pump 66. The main difference between the washing machine 2 of Fig. 11 and the arrangement shown in Fig. 13 is the position of the jet pump 66. As shown in Fig. 13, the jet pump 66 is arranged at the bottom of the washing machine (difference to the jet pump of Fig. 11 in which the jet pump 66 is fixed to the tub from below), in particular at the front of the bottom of the washing machine. Preferably, the jet pump 66 is arranged in a central or substantially central position, in particular at the front of the bottom of the washing machine. Due to this positioning of the jet pump 66, the water circulation section 64a* between the tub and the jet pump 66 and the water circulation section 64b* between the jet pump 66 and the condenser inlet (not shown) may be guided differently. Section 64a* between the filter 68 and the tub preferably runs parallel or substantially parallel to the bottom of the washing machine. Section 64b* is preferably guided above the compressor 36 and then vertically or substantially vertically and parallel along the side wall (e.g. at the corner between the front and the side wall) in the direction of the tray element 6. This arrangement has the advantage that the jet pump 66 is separate from the other pumps, in particular separated from the drain pump 72 and mixing pump 76. Thus, the replacement or service of the pumps may be simplified.

Fig. 14 is a perspective view of the washing machine of Fig. 11 without the evaporator tank water regeneration unit and with another configuration of the jet pump 66 and the condenser 81b. The main difference between the washing machine 2 of Fig. 11 and the arrangement shown in Fig. 14 is the position of the jet pump 66 and the shape of the condenser 81b. As shown in Fig. 14, the jet pump 66 is arranged at a rear position, preferably at the rear left comer of the washing machine (difference to the jet pump 66 of Fig. 11 in which the jet pump 66 is fixed to the tub from below). Due to this positioning of the pump, the water circulation section 64a* between the tub and the jet pump 66 and the water circulation section 64b* between the jet pump 66 and the condenser inlet (not shown) may be guided differently. Section 64a* between the filter 68 and the tub is preferably guided from the front to the back of the washing machine. Preferably, section 64a* is guided from the right front comer to the left rear corner of the bottom of the washing machine (i.e. shortest distance). Section 64b* is preferably guided from the outlet of the jet pump 66 vertically or substantially vertically (preferably vertically and parallel to the side walls of the washing machine) in the direction of the condenser inlet 82.

As shown in Fig. 14, the condenser inlet 82 is arranged at the rear of the top when seen the washing machine from a front view. Preferably, starting from the condenser inlet 82, the condenser 81b forms a clockwise spiral along the edges of the tray element 6. The condenser outlet 84 may be arranged parallel to the side walls of the washing machine, preferably the condenser outlet 84 is arranged on the right side of the drawer housing 12a, when seen the washing machine from a front view. By arranging the jet pump 66 at the rear side, the inner volume of the washing machine may be used more efficient as at the front now more space is available (space at the rear of the bottom of the washing machine is otherwise unused). This may open up new possibilities for the arrangement of components at the front and/or service may be carried out more easily due to the increased space at the front. Further, this positioning of the jet pump 66 and the condenser inlet 82 may result in shorter water circulation sections 64a*, 64b*.

Fig. 15 is a perspective view of the washing machine of Fig. 14 with another arrangement of the condenser 81c and the switching valve 78. As shown in Fig. 15, the condenser inlet 82 is arranged at the left side of the top of the washing machine when seen in front view. In particular, the inlet 82 is arranged at the rear, in particular, at the rear left corner of the top of the washing machine. Preferably, starting from the condenser inlet 82, the condenser 81c forms a counterclockwise spiral along the edges of the tray element 6. The condenser outlet 84 may be arranged parallel to the side walls of the washing machine, preferably the condenser outlet 84 is arranged on the right side of the drawer housing 12a, when seen the washing machine from a front view. The switching valve 78 may be arranged horizontally between the condenser inlet and outlet 82, 84, preferably parallel to the condenser inlet and outlet 82, 84. This arrangement of the condenser 81c may create more space in the region between the condenser inlet and outlet 82, 84 and thus more space for the switching valve 78. Thus, more space for mounting and service of the switching valve 78 is available.

Fig. 17 is a perspective view of the washing machine of Fig. 15 in an assembled state without the front wall, rear wall and side walls and with an evaporator tank water regeneration unit. Only the differences between the washing machine of Figs. 17 and 15 are outlined in the following. Otherwise, the elements and functions as described above with respect to the other elements of Fig. 15 correspondingly also apply individually, in subgroups or as a functional group to the embodiment of Fig. 17.

Instead of draining washing liquid from the tub and reintroducing the washing liquid into the tub by the mixing pump 76 to achieve a better mixing between the washing water and the washing liquid (i.e. detergent) as it is shown in Fig. 15, in the washing machine of Fig. 17, the washing liquid is sucked from the tub 58 and is pumped through the evaporator tank 100 as it has already been described with respect to e.g. Figs. 11, 12 and 16. 1.e. the washing machine shown in Fig. 17 is equipped with the water regeneration unit shown in Fig. 11.

The first water regeneration line 132a may guide the circulated washing liquid from the mixing pump 76 to the evaporator tank 100 in the tray element 6 of the top module via the evaporator tank inlet 130a. The second water regeneration line 132b may guide the circulated washing liquid in the evaporator tank 100 from the evaporator tank outlet 130b to the filter 68 at the bottom of the machine. From the filter 68, the liquid may be drained at least partially by the drain pump 70, wherein in particular new warm liquid from the tub may be sucked such that the liquid exiting the evaporator tank 100 is mixed at the filter 68 with fresh warm liquid from the tub. Alternatively, the second water regeneration line 132b is fluidly connected to the inside of the tub 58 to return the liquid from the evaporator tank 100 into the tub 58 and from there to the inlet of mixing pump 76.

Fig. 18 is a perspective view of the washing machine of Fig. 17 with another configuration of the evaporator tank water regeneration unit. In comparison to Fig. 17, the first water regeneration line 132a and the second water regeneration line 132b are connected to the evaporator tank 100 in reverse (i.e. when seen from a front view, line 132b at the front of the tank forms the outlet and line 132a at the rear of the tank forms the inlet of the evaporator tank). Therefore, in Fig. 18, the washing liquid entering the tank 100 flows through the tank 100 in reverse. This reversal may be applicable to all embodiments described herein by exchanging the connections of the lines 132a and 132b at the tank 100 so that the direction of flow of the washing liquid through the evaporator tank 100 is reversed.

The second water regeneration line 132b forming the outlet of the tank 100 in Fig. 18 may be connected to the tub 58 (not to the filter 68 as it is shown in Fig. 17), preferably to a nozzle 63 arranged at the bellow 62 (i.e. the bellow connecting the tub 58 to the cabinet). Preferably, the nozzle 63 is arranged at an upper region of the bellow 62 when seen from a front view (e.g. region above the rotation axis of the drum or the region above the middle level of the cabinet). In this case, the washing liquid exiting the evaporator tank 100 may be circulated through the tub 58 via the nozzle 63 arranged at the bellow 62. The washing liquid exiting the tub 58 may then be drained by the drain pump (not shown) or may be circulated again through the evaporator tank 100 by the mixing pump 76. By guiding the washing liquid into the tub 58 through the bellow 62, it is ensured that the line 132b empties itself due to the force of gravity. This reduces the risk of clogging of the line 132b due to dirt (e.g. due to fluff or deposits of the washing liquid) and/or of becoming blocked due to freezing of washing liquid remaining in the line 132b. Thus, a permanent circulation of the washing liquid through the evaporator tank 100 can be ensured.

Fig. 19 is a perspective view of Fig. 16 with another configuration of the tray element and Fig. 20 is a detailed sectional view of the evaporator tank inlet and outlet portion. Only the differences between the arrangement according to Figs. 19 and 20 and the arrangement of Fig. 16 are outlined in the following. Otherwise, the elements and functions as described above with respect to the other elements correspondingly also apply individually, in subgroups or as a functional group to the embodiment of Figs. 19 and 20.

As shown in Fig. 19, the tray element 6 comprises an evaporator tank 100 having a first and a second container chamber 35a, 35b. The first and second container chambers are fluidly separated chambers. The chambers 35a, 35b are preferably separated from each other by a separation wall inserted in the evaporator tank 100 between both chambers. The first container chamber 35a houses the evaporator 102 or at least a portion of the evaporator 102 and permanently stores the heat exchanging medium. The second container chamber 35b may be a flow through tank chamber comprising the inlet 130a and the outlet 130b, wherein the second container chamber 35b is in heat contact with the heat exchanging medium in the first container chamber 35a. The top of the second container chamber 35b may be closed by a cover. Preferably, the separation wall is formed by (or integrated in) an evaporator tank cover 32a. In addition or alternatively, the second container chamber 35b is integrated in the evaporator tank cover 32a.

Preferably, the second container chamber 35b comprises washing liquid guiding elements 37 arranged within the second container chamber 35b. The washing liquid guiding elements 37 may be formed in a single piece with the second container chamber, preferably with the evaporator tank cover 32a (i.e. the separation wall) or may be formed as a separate piece which is mounted into the second container chamber 35b (in particular on the separation wall). The evaporator tank cover 32a, in particular with the second container chamber 35b, may be formed as a separate element or in a single piece with the tray element 6. The evaporator tank 100 or at least the bottom of the tank 100 is formed as a separate element mountable to the tray element 6. Alternatively, the evaporator tank 100 may be formed in a single piece with the tray element 6. The evaporator tank cover 32a preferably seals the underlying evaporator tank 100 with the liquid stored therein. Preferably, a gasket is arranged between the evaporator tank cover 32a and the evaporator tank 100. The evaporator tank cover 32a may be mounted detachable e.g. by screws or non-detachable e.g. by welding or gluing. Preferably, the liquid stored in the tank 100 below the heat exchanger 35 is water mixed with at least one additional component such as salt water. The washing liquid guiding elements 35a may form a predetermined path for guiding washing liquid along within the tank 35b of the cover 32a. The evaporator tank cover 32a may comprise a lid 33 for sealing the second container chamber 35b from above. Preferably, a gasket is arranged between the lid 33 and the second container chamber 35b. The lid 33 may be mounted detachable e.g. by screws or non-detachable e.g. by welding or gluing.

As shown in Figs. 19 and 20, the mixing pump 76 (regeneration pump) has the same function as shown in the configurations of Figs. 11, 12 and 16. The water which is the washing liquid that was used for washing laundry in the tub is extracted from the tub. The extraction from the tub may be made through an outlet provided at the tub wall or preferably through the sump of the tub or a sump portion fluidly connected to the tub. Preferably the washing liquid is extracted downstream of a filter which is filtering the washing liquid extracted from the tub. The filter can be the filter 68 which is normally provided in the passage from the tub (e.g. from the sump) to the drain pump 72 which is draining the washing liquid e.g. after a washing or rinsing phase. The extracted washing liquid from the tub is guided by the regeneration pump 76 through the first water regeneration line 132a and through a pipe 134a which is connected to an inlet 133a into the second container chamber 35b, in particular to the upper side of the evaporator tank cover 32a. The pipe 134a preferably extends through the first container chamber 35a, in particular connects the inlet 130a of the evaporator tank 100 to an inlet 133a of the second container chamber 35b. Thus, the washing liquid is guided through the pipes 134a, 134b passing the first container chamber 35a with the washing liquid and the heat exchanging medium separated.

The second container chamber 35b is preferably in heat contact with the first container chamber 35a, in particular the washing liquid passing the second container chamber 35b is in heat contact with a gaseous volume provided above the heat exchanging medium stored in the first container chamber 35a. Preferably, when the heat exchanging medium within the evaporator tank 100 ices, the gaseous volume is filled by the iced heat exchanging medium and a heat contact between the washing liquid flowing through the second container chamber 35 and the iced heat exchanging medium is obtained. The washing liquid may flow along the washing liquid guiding elements 35a which are in thermal communication with the first container chamber (i.e. below the second container chamber) and the heat exchanging medium stored therein. While flowing along the washing liquid guiding elements 37, the heat of the warm washing liquid is transferred to the heat exchanging medium stored in the first container chamber 35a which in particular results in the melting of the ice in the first container chamber 35a. The cold washing liquid exits the second container chamber 35b, in particular the upper side of the evaporator tank cover 32a, through an outlet pipe 134b connected to an outlet 133b. The pipe 134b preferably extends through the first container chamber 35a, in particular connects the outlet 133b of the second container chamber 35b to the outlet 130b of the evaporator tank 100. Thus, the washing liquid is guided through the first container chamber 35a in the pipes 134a, 134b.

The washing liquid may flow from the outlet 130b through the second water regeneration line 132b back into the tub or the sump fluidly connected to the tub or another fluid line connected to the tub (e.g. the detergent housing or a passage from the detergent drawer to the tub. Alternatively, the washing liquid is passed into a drain line 70 that is used by the drain pump 72 for draining washing or rinsing liquid at least partially. Preferably, after draining of the washing liquid from the second container chamber 35b, new warm washing liquid is sucked from the tub and recirculated through the second container chamber 35b. Alternatively, the second water regeneration line 132b may be connected directly to the tub of the washing machine.

Fig. 21 is a schematic diagram of the functional elements used for heating and cooling the washing liquid during circulation of the washing liquid in the washing machines described above. As already described above, the washing liquid is circulated in the washing liquid circulation unit 64 and the refrigerant is circulated in the refrigerant circulation circuit 42.

In Fig. 21 the washing liquid flow direction 96 and the refrigerant flow directions 94 are indicated by arrows. Starting from a sump 140, in particular from a drain manifold or filter housing which is arranged at the lower part of the sump 140 of the tub 58 in fluid connection with the tub, the first water circulation section 64a connects a tub outlet 74 to the inlet of the circulation pump 66. Exiting the circulation pump 66 through the circulation pump outlet, the washing liquid is directed to the condenser 81 via the second water circulation section 64b. The washing liquid flows within the condenser 81 through the third water circulation section 64c.

There are two operation modes for the flow changing device 78: First the heating of the washing liquid used e.g. during a washing phase of a washing cycle and second the cooling of the washing liquid and thus the heating of the heat exchanging medium within the evaporator tank used e.g. for de-icing the evaporator (herein called regeneration mode A)), in particular during a rinsing (e.g. the last rinsing phase) of a washing cycle. The heating of the washing liquid is stopped for example if the heat transfer to the washing liquid is no longer required or possible (e.g. no circulation, washing liquid maximally heated and/or heat exchanging medium maximally depleted of heat (frozen)). Heat (e.g. residual heat of the heat pump) may be deposited in the evaporator tank during phases when washing liquid is not to be heated. This redeposited heat can be extracted in the next washing cycle for heating the circulated liquid.

In the heating mode, within the refrigerant circulation circuit 42, starting from the refrigerant condenser outlet 88, the refrigerant is directed by the first refrigerant circuit section 44D through the expansion device 40 to the evaporator 102. The compressor 36 arranged within the refrigerant circulation circuit 42 creates a vacuum applied to the evaporator 102. The heat exchanging medium in the evaporator tank 100 is in heatexchanging contact with the evaporator 102. The medium is cooled down and finally changes from the liquid to the solid phase for releasing heat. The heat released heats the refrigerant in the evaporator 102 which then evaporates. The heated refrigerant as a gas phase is sucked by the compressor 36 through the second refrigerant circuit section 46D, the switching valve 78 and the third refrigerant circuit section 48D. The compressed refrigerant is passed through the fourth refrigerant circuit section 50D, the switching valve 78 and fifth refrigerant circuit section 52D to the condenser 81 through the refrigerant condenser inlet 86. Within the condenser 81, the refrigerant and the washing liquid flow in opposite directions for an improved heat exchange. In the condenser the washing liquid is heated by transferring the heat from the refrigerant to the washing liquid. From the refrigerant condenser inlet 81 to the refrigerant condenser outlet 88, the refrigerant cools down and from the washing liquid condenser inlet 82 to the washing liquid condenser outlet 84, the washing liquid is heated.

The heated washing liquid exits the condenser 81 through the washing liquid condenser outlet 84 and the further flow path of the washing liquid may optionally be selected by a first flow diverter 144a. The first flow diverter 144a may in a first state selectively direct the washing liquid to the tub 58 through the water inlet 65 or in a second state selectively to the drawer housing 12a. Instead of providing the first flow diverter 144a, the circulated washing liquid may also be passed from the condenser outlet 84 to the drawer housing 12a.

From the drawer housing 12a the washing liquid flows into a manifold 146 which may optionally comprise a second flow diverter 144b (instead or in addition to the first flow diverter 144a). The second flow diverter 144b may selectively direct the washing liquid through the fourth water circulation section 64d and the water inlet 65 to the tub 94. The washing liquid flows through the sump 140 out of the tub and is circulated again as described above. At the end of the washing cycle, the washing liquid which exits the tub 58 through the sump 140, in particular from a drain manifold which is arranged at the lower part of the sump 140, is drained by the drain pump 72 through the water drain 70.

The cooling mode (regeneration mode A)) is used for de-icing the evaporator at the end of a washing cycle or during one or more rinsing phases. In the cooling mode the refrigerant flow direction is reverted as indicated by the white filled arrows in Fig. 57 (the black filled arrows indicate the normal flow direction for the heating process of the washing liquid). The reversal of the refrigerant flow through the condenser 81, expansion device 40 and evaporator 102 is provided by a refrigerant flow changing device 78. In refrigerant flow reversal mode the evaporator 102 works as a condenser and heats the heat exchanging medium within the evaporator tank 100. The condenser 81 operates as an evaporator and cools the circulated liquid (which is preferably freshly supplied tap water and/or water from the previous rinsing). The expansion device 40 preferably is a dual-direction expansion device, e.g. a capillary that operates independent of the flow direction.

The cooled washing liquid exiting the condenser 81 may be directed through the first flow diverter 144a to the drawer housing 12a in the fourth water circulation section 64d. Then the washing liquid may flow to the second flow diverter 144b in the manifold 146 and from there to the water inlet 65. From the water inlet 65 the liquid may flow into the tub 58 and then to the tub sump 140 and can be drained with the drain pump 72 which is connected to the sump 140, in particular to the drain manifold of the sump 140, through the water drain 70 e.g. after the de-icing of the evaporator 102. The flow changing device 78 has two switching states, wherein the refrigerant conveyance direction of the compressor 36 is not changed in both switching states. a) In a first state (normal operation state for the heat pump, heating mode as described above) the evaporator 102 operates as evaporator and the condenser 81 operates as condenser. The refrigerant compressed by the compressor and coming from the compressor outlet is directed by the switching valve 78 to the condenser 81. The refrigerant from the evaporator 102 is sucked in through the switching valve 78 to the compressor inlet. b) In a second state (regeneration mode A) in which the heat pump is operated in a reverse operation mode) the refrigerant compressed by the compressor is directed by the switching valve 78 to the evaporator 102. The refrigerant exiting the condenser is sucked in by the compressor 36 through the switching valve 78 being in its second switching state. The evaporator 102 operates as a condenser and the condenser 81 operates as an evaporator. The washing liquid within the evaporator tank 100 is heated by the evaporator 102 working as a condenser. Thus, ice formed within the evaporator tank can be melt by the second operation mode.

In addition or as an alternative to the possibility of regenerating the evaporator tank by changing the operation mode of the heat pump with a reversed refrigerant flow direction (regeneration mode A)), the regeneration unit 76, 132a, 132b described further above may be provided. The laundry treatment machine may be operated in a second regeneration mode B) in which washing liquid drained from the tub 58, in particular the sump 140, or more preferably downstream of the filter 68 (not shown) is circulated through the evaporator tank 100 with the regeneration pump 76. Therefore, warm washing liquid can be guided into the evaporator tank 100 and ice formed within the tank can be melt. The washing liquid exiting the evaporator tank 100 may be drained directly with drain pump 72 or may be guided back to the tub 58 or the sump 140 or upstream of the filter 68. Then the washing liquid may be further circulated through the evaporator tank 100 or may be drained out of the washing machine with the drain pump 72 via drain hose 70.

Further, an external evaporator 148, in particular an air heated evaporator, may be provided at the inlet of the compressor 36. In particular, the external evaporator 148 is provided between the flow changing device 78 and the inlet of the compressor 36. Refrigerant exiting the flow changing device 78 may be guided through the external evaporator 148 and then to the inlet of the compressor 36. The external evaporator 148 further heats the refrigerant and thus the washing liquid within the condenser in the normal operation of the heat pump and heats the washing liquid within the evaporator tank 100 in the reverse operation mode of the heat pump. In an air heated external evaporator 148, an air flow A (i.e. air sucked from the environment) may heat the refrigerant flowing through the external evaporator 148. Optionally, the "cooled" air exiting the evaporator is guided along the compressor 36 before being guided out of the washing machine 2 such that the compressor 36 is cooled by the air flow A. Therefore, warm air and not cold air is blown into the environment surrounding the washing machine 2 and thereby it may be prevented that operation of the evaporator 148 results in cooling of the environment. This could be inconvenient for the user especially on cold days.

Further, a heater 142 may be arranged inside the tub 58, preferably at the bottom of the tub 58 (e.g. the sump of the tub), for heating the washing liquid. If the heat pump system is defect, the washing machine may also be operated normally by using the heater 142 for heating the washing liquid.

The functional arrangement shown in Fig. 21 is applicable to all above embodiments of a laundry treatment machine. In particular applicable in all embodiments of a washing machine which are disclosed herein in more detail. Although not shown in the detailed embodiments above, for example the first and/or second flow diverter 144a, 144b may be provided.

Fig. 22 shows a schematic block diagram of a control unit 150 and its input and output signals. The control unit 150 may be adapted to control the machine in the first regeneration mode A) and in the second regeneration mode B), wherein in the first regeneration mode A) the heat pump is in the reverse operation mode, and wherein in the second regeneration mode B) the regeneration unit (see Fig. 21: 76, 132a, 132b) is circulating the washing liquid.

In particular, the control unit 150 may control the switching element 78 to switch from the first state (normal operation of heat pump) to the second state (reverse operation of the heat pump = regeneration mode A)) in which the refrigerant flow is reversed and the condenser 81 operates as an evaporator and the evaporator 102 as a condenser (i.e. washing liquid within evaporator tank is heated). Preferably, the washing liquid is circulated by washing liquid circulation unit in which the washing liquid is circulated from the tub 58 through the condenser 81 and back to the tub 58. More preferably, the washing liquid circulation through the washing liquid circulation unit 64 and the regeneration mode A) are executed at least partially simultaneously.

The control unit 150 may further control the regeneration pump 76 to circulate washing liquid from the tub through the evaporator tank 100 and then back to the tub 58 or sump or a filter arranged upstream of the regeneration pump 76. The control unit 150 may control the drain pump 72 to drain the washing liquid from the tub 58, or in particular to drain the washing liquid circulated through the evaporator tank 100.

The control unit 150 may further control the compressor 36, e.g. by switching it on or off or by adjusting the speed of the compressor e.g. in case of a variable speed compressor and/or may control the water heater 142 within the tub for heating the washing liquid.

For selecting regeneration modes A) and/or B), the control unit 150 may take into account at least one temperature signal indicative of one or more of the following:

- a compressor temperature T36,

- a refrigerant temperature Trefrig. (e.g. at the compressor or at the evaporator within the evaporator tank 100),

- a washing liquid temperature Two within the evaporator tank 100,

- a condenser temperature Tsi of the washing liquid or of the refrigerant flowing through the condenser, and

- a washing liquid temperature T 142 at the heater 142.

The temperature of the heat pump, i.e. the refrigerant temperature Trefrig. and/or the temperature of the compressor T36, and/or the temperature of the condenser Tsi may be used for determining the operation time of the heat pump system to heat up the laundry washing liquid. If the operation time is long, the regeneration period(s) can be extended. For extraction the same amount of heat, longer time is available and regeneration mode B) can be used instead of regeneration mode A) which would be required at shorter regeneration periods.

The washing liquid temperature T o and/or the condenser temperature Tsi and/or the compressor temperature T36, and/or the refrigerant temperature Trefrig may be used for indirectly determining the freezing status of the laundry washing liquid in the evaporator tank 100. The lower the temperature Two, the higher the formation of ice within the evaporator tank 100. Therefore, if temperature Two is low/medium, the need for regeneration is high/average and regeneration mode A)+B) or A) may be preferred. If the temperature Two within the tank is high, there is small amount of ice within the tank, such that the need for regeneration is low. In this case, regeneration B) may be preferred.

Further, the washing machine may comprise for regeneration mode B) a flowmeter for measuring the washing liquid flow through the evaporator tank 100 and/or a pressure/temperature sensor at the evaporator 102 in the evaporator tank 100 for measuring the pressure/temperature within the evaporator tank 100. E.g. a sensor may detect a huge amount of ice within the evaporator 102 which leads to a low gradient of temperature change over time in the evaporator tank 100. Then regeneration mode B) would be less efficient and regeneration mode A) is therefore selected in dependency of the signal of the sensor.

High temperature of the washing liquid (e.g. above 60 °C) within the tub, i.e. the washing liquid temperature T142 at the heater 142, may result in a huge amount of ice in the evaporator tank 100. If the temperature is high, regeneration mode A) may be preferred instead of regeneration mode B).

Further, the control unit 150 may receive input from the control panel 14 which is used for selecting the first and/or second regeneration modes A)+B). By using the control panel 14, the user may select a laundry treatment program. The laundry treatment program may comprise commands for regeneration modes A) and/or B) which are received and executed by the control unit 150. The user or the laundry treatment program may further set a washing liquid temperature. Preferably regeneration mode B) is selected if a half load cycle (i.e. small amount of ice is formed in the evaporator tank, e.g. a short time program) and/or a laundry treating temperature less than 50 °C, 45 °C, 40 °C or 35 °C is selected by the user. A low temperature and/or a short time program results in small amount of ice. Regeneration mode A) may be selected if a long main wash program and/or a high washing liquid temperature is selected by the user. Long washing programs and/or high washing temperatures may result in a high volume or rate of ice formed within the evaporator tank.

By using the control panel 14, the user may further select a number of rinsing phases. If there is a plurality of rinsing phases, e.g. three rinsing phases, the laundry treatment machine may be operated in the first rinsing phase only in regeneration mode B), in the second rinsing phase only in regeneration mode A) and in the third rinsing phase in regeneration modes A) and B). Thereby in the first rinsing the higher or non-reduced rinsing temperature preserves a better rinsing efficiency for dissolving detergent residuals and in the last rinsing full heat of the rinsing liquid is extracted.

By using the control panel 14, the user may select the first and/or second regeneration mode A)+B) via control panel 14. E.g. if the user does not have much time and wants a fast wash, she/he may select regeneration mode A).

By using the control panel 14, the user may select a command causing a modification in the execution of phases of an originally started laundry treating program. The user may modify the main wash phase and/or the rinsing phase(s); e.g. the user may shorten the selected treating program by e.g. skipping rinsing phases (e.g. when the user comes home and does not want to wait any longer). By shortening of the treating program, the time for regeneration is reduced such that in this case regeneration mode A) instead of B) or A)+B) instead of A) may be preferred.

The control unit 150 may send an alarm signal to the control panel 14 indicating that one of the regeneration modes A) and B) is not available. If one of the first and second regeneration modes may not be available, e.g. if the heat pump system has a defect, regeneration mode A) is not available and regeneration mode B) is selected. In addition, a heater arranged within the tub for heating the washing liquid may be used for additionally heating the washing liquid during regeneration mode B) such that the regeneration is speed up.

The laundry treatment apparatus may comprise the heater 142 which is preferably an electrical heater. Preferably and if sufficient heat can be extracted from the evaporator tank, the washing liquid is heated exclusively by the condenser of the heat pump system. However the heater is preferably provided to co-heat the washing liquid if the washing temperature to be achieved is higher than can be achieved by the condenser-heating and/or the heating time for exclusive condenser heating would extend the wash time to overall wash cycle times inconvenient for the user.

If e.g. regeneration mode B) is not available, regeneration mode A) is selected and the evaporator tank is regenerated by regeneration mode A), wherein in addition the heater within the tub may be used for heating the washing liquid and thus for increasing the heat exchange with the refrigerant in the condenser. Thus the regeneration by regeneration mode A) is supported by the heater. This may be applicable if e.g. the temperature of the washing liquid within the tub is low.

The control unit 150 may further receive a signal indicative of an ambient temperature TA for controlling the operation of the external evaporator 148 (see Fig. 21).

In the following table, the characteristics of the different regeneration modes A) and/or B) which have been described above are summarized:

In regeneration mode A), the refrigerant flow direction is reversed by the switching element 78 and thus the heat of the washing liquid within the tub is extracted and transferred to the evaporator tank. In regeneration mode B), the washing liquid from the tub is circulated through the evaporator tank with regeneration pump 76. In regeneration mode A)+B) the washing liquid of the tub is circulated through the evaporator tank and the refrigerant flow direction is reversed such that the refrigerant heats up the washing liquid within the evaporator tank.

During both operation modes A) and B), heat is transferred to the evaporator tank and thus ice formed within the evaporator tank can melt. Regeneration mode A) may have a higher regeneration efficiency than regeneration mode B), wherein the combination of both modes A)+B) may have the highest efficiency.

Fig. 23 shows different implementations of regeneration modes in main wash and rinsing phases.

Fig. 23 i) is a conventional washing program including a main washing phase (e.g. duration of 130 min) with a high washing liquid temperature of e.g. 70 °C, a first, second and third spinning phase, wherein a first rinsing phase (e.g. 5 mins) is executed between the first and second spinning phase and a second rinsing phase (e.g. 8 mins) is executed between the second and third spinning phase. The first rinsing phase may take 5 mins and the second rinsing phase may take 8 mins. The high washing liquid temperature of 70 °C may be achieved by using an electrical heater, e.g. the water heater 142, with a high heating power of e.g. 1950 W.

Fig. 23 ii) shows the washing program of Fig. 23 i) with additional regeneration. A high washing liquid temperature like e.g. 70 °C leads to a huge amount of ice in the evaporator tank. Therefore, there is a high need for regeneration. A regeneration, preferably regeneration modes A)+B) for extracting the maximum heat amount, may be executed during the main wash phase, in particular during the last 30 or 40 mins of the main wash phase. In addition or alternatively, regeneration may be executed during at least one of the rinsing phases, wherein the regeneration may be executed partially during a rinsing phase or during the complete rinsing phase. In particular, regeneration mode A) may be executed during the first rinsing phase and regeneration modes A)+B) during the second rinsing phase. In the first rinsing phase medium heat amount may be extracted by regeneration mode A) and in the second rinsing phase maximum heat amount may be extracted by regeneration modes A)+B). The electrical heater may have a lower heating power than in Fig. 23 i), e.g. 1000 W, because heat of the washing liquid is extracted by the regeneration modes.

Fig. 23 iii) shows a washing program similar to Fig. 23 ii), but the washing liquid temperature is medium, e.g. 50 °C. Therefore, the formation of ice within the evaporator tank is medium and the need for regeneration is thus average/medium. The regeneration during the main wash phase may then be executed by using regeneration mode A) having a medium regeneration efficiency/speed. In the first rinsing phase low heat amount may be extracted by regeneration mode B) and in the second rinsing phase medium heat amount may be extracted by regeneration mode A). If the washing liquid temperature is medium e.g. 50 °C, regeneration mode B) may be used during the first rinsing phase instead of A) or A)+B) such that low heat amount is extracted at the first rinsing phase for preserving rinsing efficiency.

Fig. 23 iv) shows a washing program which is similar to the washing program of Fig. 23 iii) but the main wash phase and/or the rinsing phases may be longer. E.g. the main wash phase may be 145 mins instead of 130 mins, the first rinsing phase 10 mins instead of 5 mins and the second rinsing phase 13 mins instead of 8 mins. Therefore, the regeneration time is extended. By extending the phases, there is more time for regeneration, and thus more time for extracting the same amount of heat. Thus, regeneration mode B) may be used during the second rinsing phase instead of A) (Fig.

23 iii)) which would be required at shorter regeneration periods. The heating power of the electrical heater may be lower compared to Fig 23. ii) and iii), e.g. 800 W because if the washing phase is extended, there is more time for heating the washing liquid.

In the following, further examples for combinations of regeneration modes during the main wash phase and at least one rinsing phase in dependency of the washing liquid temperature are shown:

The higher the washing liquid temperature, the higher the amount of ice in the evaporator tank and therefore the higher the need for regeneration.

At low/medium temperature the rinsing efficiency may be low if much heat is extracted by the regeneration modes. Thus, at low/medium temperature low heat amount is extracted at a first rinsing phase for preserving the rinsing efficiency. In a second rinsing phase medium heat amount is extracted at low/medium wash temperature and maximum heat amount is extracted at high washing temperatures. In the third rinsing phase maximum heat amount is extracted.

Fig. 24 shows the coefficient of performance (COP) when the evaporator tank is regenerated via regeneration mode A) in the last part of the main wash. The graph shows the COP when the evaporator tank is regenerated via [A] in the last part of the main wash, in particular at the end of the heating phase. During the heating phase, in this case, the washing liquid is only heated by the heat pump. No additional heating by an electrical heater is provided, but may be applicable. By switching the refrigerant flow direction, the washing liquid within the evaporator tank is heated up and the ice within the evaporator tank is melt.

COP Heating: 650Wh/240Wh=2.7; COP regeneration = 470Wh/45Wh=10.4; Total COP: 650Wh/(240Wh+45Wh)=2.28.

It should be clear to the skilled person that the all the structural features and different configurations of the regeneration modes A) and B) described above are also applicable to the washing cycle of a washer dryer.

Reference Numeral List

2 washing machine

4 cabinet

5 top module

6 tray element

7 peripheral outer side (wall)

8 front wall

9 top wall (work top)

10 side wall

12 detergent drawer

12a drawer housing

13 handle

14 control panel

16 loading opening

18 door

22a service cover/ filter opening

24 rear wall/back-wall

28 balance weight

30 spring dampers

32, 32a evaporator tank cover

33 lid for evaporator tank cover

34 seat/ribs for receiving thermo-insulating material

35a, 35b first / second container chamber

36 compressor

37 washing liquid (separation) guiding element

40 expansion device (capillary or expansion valve)

42 refrigerant circulation circuit

44D first refrigerant circuit section (between refrigerant condenser outlet and evaporator inlet, considering the heat pump refrigerant flow direction)

46D second refrigerant circuit section (between evaporator outlet and first inlet of switching valve, considering the heat pump refrigerant flow direction)

48D third refrigerant circuit section (between first outlet of switching valve and compressor inlet, considering the heat pump refrigerant flow direction) 50D fourth refrigerant circuit section (between compressor outlet and second inlet of switching valve, considering the heat pump refrigerant flow direction)

52D fifth refrigerant circuit section (between second outlet of switching valve and condenser inlet, considering the heat pump refrigerant flow direction)

54 sixth refrigerant circuit section / condenser outer tube (within outer tube of the condenser)

56 bottom

58 tub

60 drum

62 bellow / gasket

63 inlet (nozzle) into tub for water from evaporator tank

64 washing liquid circulation unit

64a, 64a* first water circulation section (between tub outlet (e.g. via the sump) and inlet of circulation pump, considering the washing liquid flow direction)

64b, 64b* second water circulation section (between outlet of circulation pump and outlet of condenser, considering the heat pump refrigerant flow direction)

64c third water circulation section / condenser inner tube (within condenser)

64d fourth water circulation section (between condenser inlet and water inlet to tub, considering the heat pump refrigerant flow direction and water inlet)

65 water inlet into tub (nozzle)

66 circulation pump (jet pump)

68 filter / service opening

70 water drain / drain hose

72 drain pump

74 tub outlet (e.g. via the sump)

76 mixing pump / regeneration pump

77 return line to tub

78 switching element / switching valve / refrigerant flow changing device

81, 81b, 81c condenser

82 washing liquid condenser inlet

84 washing liquid condenser outlet

86 refrigerant condenser inlet 88 refrigerant condenser outlet 92 damping element / vibration dampers 94 refrigerant flow direction 96 washing liquid flow direction 100 evaporator tank 102 evaporator 104 evaporator inlet 106 evaporator outlet 108 mounting element (for evaporator) 110 compressor inlet 112 compressor outlet 118 condenser smaller/inner tube (washing liquid) 120 condenser larger/outer tube (refrigerant) 122 insulation layer 128 maintenance opening 130a evaporator tank inlet (or outlet) 130b evaporator tank outlet (or inlet) 132a first water regeneration line (to evaporator tank) 132b second water regeneration line (from evaporator tank) 133a, 133b inlet / outlet of second chamber container 134a, 134b first / second pipe section for guiding water within evaporator tank 138 fixing element for evaporator pipes 140 tub sump 142 water heater 144a, 144b first/second flow diverter / washing liquid directing device (optional) 146 manifold 148 external (air heated) evaporator 150 control unit A air flow TA ambient temperature

T36, Tsi, T100, T142 water/refrigerant/heat exchange medium temperature

Claims

Claims:

1. Method for operating a laundry treatment machine, in particular a washing machine or a washer dryer, the laundry treatment machine (2) comprising: a cabinet (4) housing a tub (58) and a drum (60) rotatably arranged in the tub (58) for washing laundry therein, a heat pump having a compressor (36), an evaporator (102) and a condenser (81), the condenser (81) being adapted to heat washing liquid, an evaporator tank (100) housing the evaporator (102) or at least a portion of the evaporator (102), wherein the evaporator tank (100) is a tank for storing a heat exchanging medium, a regeneration unit (76, 132a, 132b) adapted to circulate the washing liquid with a regeneration pump (76) from the tub (58) or a tub sump (140) through or along the evaporator tank (100) and back to the tub (58), in particular back to the sump (140) or a filter arranged upstream of the regeneration pump (76), and a refrigerant flow changing device (78) adapted to change between a normal operation mode of the heat pump and a reverse operation mode of the heat pump, wherein in the normal operation mode of the heat pump, the condenser (81) is adapted to heat the washing liquid and the evaporator (102) is adapted to cool the heat exchanging medium, and wherein in the reverse operation mode of the heat pump, the condenser (81) is adapted to cool the washing liquid and the evaporator (102) is adapted to heat the heat exchanging medium, wherein operating the laundry treatment machine comprises: operating the laundry treatment machine in a first regeneration mode A) where the heat pump is in the reverse operation mode, and operating the laundry treatment machine in a second regeneration mode B) where the regeneration unit is circulating the washing liquid.

2. Method according to claim 1, wherein the method further comprises operating the laundry treatment machine during a laundry treatment cycle at least partially simultaneously in the first and second regeneration mode A)+B), and/or at least partially exclusively in the first and/or in the second regeneration mode A) or B).

3. Method according to claim 1 or 2, wherein the method further comprises operating during a laundry treatment cycle the laundry treatment machine in the first regeneration mode A) or in the second regeneration mode B) or simultaneously in the first and second regeneration mode A)+B) depending on one or more of the following operation parameters of the laundry treatment machine: a) a treating program selected by a user; b) a washing liquid temperature; c) a number of rinsing phases selected by the user or provided by a laundry treatment machine control unit (150); d) an operation time of the heat pump system to heat up the washing liquid; e) a signal of a sensor indicating the freezing status of the washing liquid in the evaporator tank; f) a regeneration type user selection; g) an alarm signal indicating that one of the first and second regeneration modes is not available; h) a user command causing a modification in the execution of phases of an originally started treating program; and i) a signal of a sensor detecting the temperature of the washing liquid in the tub and/or in the evaporator tank.

4. Method according to claim 1, 2 or 3, wherein the first regeneration mode A) and/or the second regeneration mode B) are executed at the end of a main wash phase of a washing program and/or during at least one rinsing phase.

5. Method according to any of the preceding claims, wherein the laundry treatment machine further comprises a washing liquid circulation unit (64) for circulating the washing liquid from the tub (58) through the condenser (81) and back to the tub (58), wherein the washing liquid circulation through the washing liquid circulation unit (64) and the first regeneration mode A) are executed at least partially simultaneously.

6. Method according to any of the preceding claims, wherein the regeneration pump (76) of the regeneration unit (76, 132a, 132b) is a variable speed pump.

7. Method according to claim 6, wherein a speed level and/or a speed driving profile of the variable speed pump are selected in dependency of at least one of the following parameters:

- a treating program selected by a user;

- a washing liquid temperature;

- an operation time of the heat pump system to heat up the washing liquid;

- a signal of a sensor indicating the freezing status of the washing liquid in the evaporator tank;

- a user command causing a modification in the execution of phases of an originally started treating program;

- a signal of a sensor detecting the temperature of the washing liquid in the tub and/or in the evaporator tank; and

- a number of rinsing phases selected by the user or provided by a laundry treatment machine control unit (150).

8. Laundry treatment machine, in particular a washing machine or a washer dryer, comprising: a cabinet (4) housing a tub (58) and a drum (60) rotatably arranged in the tub (58) for washing laundry therein, a heat pump having a compressor (36), an evaporator (102) and a condenser (81), the condenser (81) being adapted to heat washing liquid, an evaporator tank (100) housing the evaporator (102) or at least a portion of the evaporator (102), wherein the evaporator tank (100) is a tank for storing a heat exchanging medium, a regeneration unit (76, 132a, 132b) having a regeneration pump (76) adapted to circulate the washing liquid from the tub (58) or sump (140) through or along the evaporator tank (100) and back to the tub (58) or sump (140), and a refrigerant flow changing device (78) adapted to change between a normal operation mode of the heat pump and a reverse operation mode of the heat pump, wherein in the normal operation mode of the heat pump, the condenser (81) is adapted to heat the washing liquid and the evaporator (102) is adapted to cool the heat exchanging medium, and wherein in the reverse operation mode of the heat pump, the condenser (81) is adapted to cool the washing liquid and the evaporator (102) is adapted to heat the heat exchanging medium.

9. Laundry treatment machine according to claim 8, wherein the laundry treatment machine further comprises a top module (5), and wherein when the top module (5) is mounted at the laundry treatment machine

(2) it is forming part of the cabinet (4) as a top; wherein preferably the top module (5) comprises the evaporator tank (100) and the evaporator (102).

10. Laundry treatment machine according to claim 8 or 9, wherein the refrigerant flow changing device (78) comprises a refrigerant inlet and a refrigerant outlet and which is adapted in a first switching state to fluidly connect the refrigerant inlet to a first pipe of the refrigerant circuit and the refrigerant outlet to a second pipe of the refrigerant circuit, and in a second switching state to fluidly connect the refrigerant inlet to the second pipe of the refrigerant circuit and the refrigerant outlet to the first pipe of the refrigerant circuit.

11. Laundry treatment machine according to claim 8, 9 or 10, wherein the machine further has a control unit (150) and the control unit is adapted to control the machine in a first regeneration mode A) and in a second regeneration mode B), wherein in the first regeneration mode A) the heat pump is in the reverse operation mode, and wherein in the second regeneration mode B) the regeneration unit (76, 132a, 132b) is circulating the washing liquid.

12. Laundry treatment machine according to claim 11, wherein the control unit (150) is adapted to control the machine such as to apply the first regeneration mode A) and the second regeneration mode B) at least partially simultaneously during a laundry treatment cycle.

13. Laundry treatment machine according to any of claims 8 to 12, wherein the regeneration pump (76) of the regeneration unit (76, 132a, 132b) is a variable speed pump.

14. Laundry treatment machine according to any of claims 8 to 13, wherein the laundry treatment machine further comprises a heater (142) arranged within the tub (58) for heating the washing liquid.

15. Laundry treatment machine according to any of claims 8 to 14, wherein the machine further comprises an external evaporator (148), in particular an air-heated evaporator, arranged at an inlet of the compressor (110) for heating the refrigerant of the heat pump.

16. Laundry treatment machine according to claim 15, wherein the machine further comprises a cooling path adapted to route cool air (A) from the external evaporator (148) along the compressor (36) of the heat pump, and/or a condensate collector arranged below the external evaporator (148) and being adapted to collect condensate formed on and dripped down from the external evaporator (148).