CN112127120B

CN112127120B - Laundry care appliance with pump device and method for operating a laundry care appliance

Info

Publication number: CN112127120B
Application number: CN202010580622.1A
Authority: CN
Inventors: K·哈恩; R·勒默尔; S·韦策尔
Original assignee: BSH Hausgeraete GmbH
Current assignee: BSH Hausgeraete GmbH
Priority date: 2019-06-25
Filing date: 2020-06-23
Publication date: 2023-12-12
Anticipated expiration: 2040-06-23
Also published as: EP3757273B1; DE102019209149A1; CN112127120A; PL3757273T3; EP3757273A1

Abstract

The invention relates to a method for operating and a laundry care appliance having a lye container with a discharge opening and an inlet element, a pump device, a discharge line connecting the discharge opening to the pump device, a pump-out line connecting the pump device to an outer region of the laundry care appliance, and a circulation pump line connecting the pump device to the inlet element. The pump device has a first pump for pumping the washing liquid from the lye container via the pump-out line and from the laundry care appliance, and a second pump for re-feeding the washing liquid from the lye container via the circulation pump-out line and via the inlet element. A pump is activated during a first period of time to pump wash liquid into the pump-out line or to circulate the liquid level in the pump-out line. And activating another pump in a second time period to pump the washing liquid from the pumping pipeline or the circulating pumping pipeline to the liquid level in the other pipeline corresponding to the pumping pipeline or the circulating pumping pipeline respectively.

Description

Laundry care appliance with pump device and method for operating a laundry care appliance

Technical Field

The invention relates to a laundry care appliance having a pump device and to a method for operating such a laundry care appliance.

Background

In conventional laundry care appliances, a laundry care substance (e.g., a different detergent or softener) is given by a user into a wash-in housing of the laundry care appliance. Water is supplied to the wash-in housing via a water connection of the laundry care appliance, wherein the laundry care substance is flushed from the wash-in housing by the supplied water and supplied to the lye container. The laundry care substance, which is present in most cases as a powder, then forms a solution in the lye container with the amount of water flushed in. This dissolution process is mainly carried out in a diffusion manner (diffusion art) and thus requires a certain period of time. This time period can be shortened by: the water which is flushed in is brought into motion in the lye container, for example by rotation of a drum, so that the dissolution process additionally takes place also in a countercurrent manner (konvektioonsartig). In the event of improper overdosing of the laundry care substance by the user, the laundry care substance dissolution process may be prolonged or the powdered laundry care substance may not be completely dissolved. Undissolved laundry care materials in the lye container can damage the laundry to be treated in high concentrations in certain cases and can cause discoloration of the laundry, especially when detergent residues come into contact with the laundry.

In GB 2,099,462A washing machine is disclosed in which excessive consumption of laundry care substances is to be avoided. The washing machine is provided for: during the washing process, the pump is briefly and intermittently switched on in order to feed the washing liquid with the laundry care substance into the pump-out hose, wherein the washing liquid alternately rises and sinks in the pump-out hose, whereby the laundry care substance should be dissolved.

In the circulation pumping system in conventional laundry care appliances, the washing liquid is pumped out of the lye container by means of a second pump (in particular a circulation pump) and is re-fed to the laundry via the circulation pumping line and via the inlet element.

In the conventional circulating pumping system in the washing nursing appliance, the overflow sealing mechanism of the alkali liquor container is generally eliminatedltersumpfversschlus) because there is no concern about detergent depletion due to the presence of the circulation pumping system, in which case the detergent concentration in the wash liquor becomes smaller. Undissolved, usually still powdery, detergent (which has been released by gravity through the opening of the lye containerOpen lye container without participating in the washing process) can be immediately re-fed to the lye container and thus to the laundry as a result of the activation of the circulation pump, wherein here the detergent should in particular already be present in dissolved form to the greatest extent in order to prevent fading damage of the laundry. With the circulation pumping system in conventional laundry care appliances, after the end of the laundry care process, the consumed washing liquid is pumped out of the laundry care appliance by means of a first pump (in particular a pump-out pump) via a pump-out line.

In WO 2017/039549 A1 a method for dissolving detergent in a washing machine with a circulation pumping system is disclosed. In this method, the pump is briefly switched on and off at intervals during the washing process in order to feed the washing liquid with the detergent into the circulation pump hose, wherein the pump is stopped before the washing liquid reaches the highest point in the circulation pump hose.

In the method according to GB 2 099 462A and WO 2017/039549 A1, it is disadvantageous that after switching off the pump-out pump (or circulation pump), the washing liquid flows back uncontrollably, whereby it may occur that the washing liquid with undissolved detergent may flow back into the laundry drum. Thus, it is not possible to reliably prevent: contact of highly concentrated detergent with the wash and localized wash fade.

Disclosure of Invention

The object of the invention is, inter alia, to provide a laundry care appliance and a method for operating such a laundry care appliance, in which an advantageous dissolution of the laundry care substance in the washing liquid is improved (in particular ensured). In addition, the washing care appliance and the operation method provided by the invention can realize the improved self-cleaning effect of the pump device and the connected liquid guide route.

This object is achieved by the subject matter having the features according to the invention. The advantageous embodiments are the subject matter of the description and the drawings, wherein an advantageous embodiment of the laundry care appliance can simultaneously realize an advantageous embodiment of the method for operating the laundry care appliance, and vice versa.

According to a first aspect, the object of the invention is achieved by a laundry care appliance having: lye container for receiving a washing liquid, wherein the lye container has a discharge opening and an inlet element (in particular an inlet nozzle); pump means for pumping the washing liquid; a discharge line fluidly connecting the discharge opening with the pump apparatus; a pump-out line fluidly connecting the pump device with an external region of the laundry care appliance; a circulation pumping line connecting the pump device with the inlet element in terms of fluid technology, wherein the pump device has a first pump which is configured for: pumping the washing liquid (in particular with a calibrated pumping power) from the lye container via the discharge opening, via the discharge line and via the pump-out line out of the laundry care appliance, wherein the pump device has a second pump which is configured for: the washing liquid is pumped (in particular with a calibrated pumping power) from the lye container via the discharge opening and via the discharge line into the circulation pumping line, and the washing liquid is re-fed from the circulation pumping line and via the inlet element into the lye container, and the laundry care appliance has a control device for controlling the pump device, wherein the control device is configured for: one of the pumps of the pump device for pumping the washing liquid is activated for a first period of time (in particular with reduced pumping power) in order to pump the washing liquid to the liquid level in the pump-out line or to the liquid level in the circulation pump-out line, and wherein the control device is configured for: in a second period of time, which follows the first period of time, in particular with a reduced pumping power, the other of the pumps of the pump device for pumping washing liquid is activated in order to pump washing liquid from the respective pump-out line or circulation-pump line and to pump the pumped washing liquid to the liquid level in the pump-out line or the respective other line of the circulation-pump line, i.e. the circulation-pump line or the pump-out line.

The following technical advantages are achieved: a more efficient and faster dissolution of the laundry care substance in the washing liquid can be ensured, since the laundry care substance is not only dissolved by a slower diffusion process, but the processes can be superimposed by additional convection. In this case, it is particularly advantageous if, by means of the transport (or counter-transport) of the washing liquid between the pump-out line and the circulation pump-out line, a higher flow speed can be produced by a smaller line cross section of the pump-out line (or circulation pump-out line) relative to the discharge line, and thus a convection effect can be enhanced. Furthermore, wetting of the wash liquor by means of the not yet completely dissolved detergent is avoided, since this counteracts the countercurrent flow of the wash liquor into the lye container. Furthermore, the resulting flow of the washing liquid allows contaminants or blockages that may accumulate in the line and/or the pump to be dissolved, whereby a self-cleaning effect of the line can be achieved.

Preferably, the control device is especially configured for: activating a delivery operating mode of the first pump with reduced pumping power for a first period of timeIn order to pump (or lift) the washing liquid to a liquid level (flusseigkeitspegel) in the pump-out line, and the control device is configured in particular for: the second pump is activated with a reduced pumping power during a second period of time immediately following the first period of time in order to pump the washing liquid from the pump-out line and to pump (or lift) the pumped washing liquid to the liquid level in the circulation pumping line. The first pump is here turned off in particular as the second pump is activated.

Alternatively, the control device is especially configured for: the delivery operating mode of the second pump is activated with reduced pumping power for a first period of time in order to pump the washing liquid to the liquid level in the circulation pumping line, and the control device is configured in particular for: the delivery mode of operation of the first pump is activated with a reduced pumping power during a second period of time immediately following the first period of time in order to pump the washing liquid from the circulation pumping line and to pump the pumped washing liquid to a liquid level in the pump-out line without a delivery flow being established when the liquid level is reached. The second pump is here turned off in particular as the first pump is activated.

In particular, by activating the further pump in a second period of time after the first period of time, the technical advantage is achieved that: by pumping (or lifting) the washing liquid by the respective pump during the first time period and by the subsequent (in particular active) return-guiding of the pumped washing liquid there by the further pump, an effective dissolution of undissolved residues of the laundry care substance in the washing liquid is achieved. The advantageous dissolution of the laundry care substance is ensured by the strong convection of the washing liquid with the laundry care substance, which occurs when the washing liquid actively flows through the pump device, wherein this strong convection is caused in particular by the high flow velocity of the washing liquid on the respective pump impeller of the respective pump.

The dissolution of the laundry care substances in the washing liquid is improved by this convection in a plurality of times, and thus takes place more rapidly than in the case of the convection dissolution processes known from the prior art or than if the dissolution process were to take place diffusely.

In conventional laundry care appliances, the laundry care substance is pre-dosed into the wash-in housing by the user. The washing water is flushed into the flush-in housing via the water connection of the laundry care appliance, and the mixture of laundry care substance and water is flushed as washing liquid from the injection line into the lye container. In most cases, the detergent, which is still in powder form, is deposited at the bottom in the lye container and is conditionally very slowly dissolved with the washing liquid in a diffuse manner. In general, the dissolution process of the powdery laundry care substances is slightly improved in a convective manner by the rotation of the washing drum.

In this case, in particular, the laundry care substance present in the washing liquid cannot be completely dissolved due to an improper dosing by the user, so that undissolved residues of the laundry care substance (for example, a powdery detergent) may remain in the washing liquid. Undissolved residues of the laundry care substances can cause discoloration damage on the laundry to be treated in high concentrations and should therefore be avoided.

A circulation pumping system and a method for detergent dissolution are known from WO 2017/039549 A1, however, such fading damage still cannot be reliably avoided by means of such a laundry care appliance.

In the laundry care appliance according to the invention, the respective pump pumps the washing liquid into the pump-out line or into the circulation pump-out line for a first period of time until the pumped washing liquid reaches a liquid level in the respective line, so that the transport flow is stopped and only one liquid column on the pressure side is established. By performing a delivery interruption (or delivery reduction) or a liquid column built solely on the pressure side after the first period of time, it is possible to prevent: the pumped washing liquid is either fed to the washing from the circulation pumping line via the inlet element or pumped out of the washing care implement via the pump-out line during the first period. In this case, the first or second pump of the circulation pump system is operated in particular at a reduced number of impeller revolutions, so that the liquid column on the pressure side is lifted and a continuous transport flow is not, however, formed.

After the end of the first time period, the other one of the pumps is activated during a second time period, wherein washing liquid is pumped from the respective pump-out line or circulation pump-out line and the pumped washing liquid is pumped to the liquid level in the respective other one of the pump-out line or circulation pump-out line (i.e. the circulation pump-out line or pump-out line). In this case, a reduced number of impeller revolutions can be used again for the pump drive, so that a transport flow is briefly established, which flow occurs as soon as the pressure side has formed a water column of the desired liquid level in the corresponding further pressure line.

The pumps thus pump the washing liquid back and forth between the pump-out line on the pressure side (first drainage component) and the circulation pump-out line on the pressure side (further drainage component) in the first and second time periods, whereby an advantageous dissolution of the washing care substance in the washing liquid is achieved as a result of the corresponding convection (which is achieved by the flow velocity in the drainage system component on the pressure side), whereby the washing liquid can be fed to the washing in the washing drum in the following circulation pump-out process without damage or discoloration on the washing caused by undissolved residues of the washing care substance occurring. In particular, this method is characterized in that after the first pump is switched off, a further pump is specifically activated in order to controllably convey the washing liquid that flows back as a result of the switching off of the first pump from one drain element in the pressure-side drain system to the other drain element on the pressure side. In addition to the high flow speeds determined by the cross section in these drainage members, this has the advantage that: uncontrolled backflow of washing liquid into the lye container can be avoided.

In order to prevent washing liquid from being pumped out of the laundry care appliance, the liquid level in the pump-out line is located in particular below the discharge opening. If the pump-out line has a section, which extends above the outlet opening (i.e. at a geodetically higher potential), depending on the user-specific placement conditions, the liquid level is located in particular below the section of the pump-out line extending above the outlet opening. Furthermore, the pump-out line can be configured such that the pump-out line is divided into a pump-side line section and a discharge-side line section, wherein the pump-side line section and the discharge-side line section are connected to one another in the upper region of the laundry care appliance. This embodiment is also referred to as "Shui Shan (Wasserberg)". In this embodiment, the pumping out of the washing liquid is prevented if it is ensured that the liquid level in the pump-side line section of the pump-out line is located in particular below the upper point of the pump-out line (in particular the connection point between the pump-side line section and the outlet-side line section). This embodiment has the advantage that: the discharge opening may also be located below the liquid level.

In order to prevent the washing liquid from being re-fed to the washing items via the inlet element, in particular the spray nozzle, before the washing agent is completely dissolved, the second liquid level in the circulation pumping line is located in particular below the inlet element. If the circulation pumping line has a section extending above the inlet element (i.e. at a geodetically higher potential), the liquid level is located in particular below the section of the circulation pumping line extending above the inlet element.

In view of this increased liquid level in the previously described part, the detergent dissolution described here can be optimized, since on the one hand an increased flow speed occurs which promotes convection for the detergent dissolution. On the other hand, a longer time is necessary for the transfer, whereby an increased liquid level is formed in the pressure lines of the hydraulic circuit system and the hydraulic evacuation system, so that the relationship between the pumping time and the holding time at the vibration reversal point is improved in the case of the maximum amplitude of the vibrations at the liquid level reached. Eventually, the pumping time is prolonged, while the holding time at the commutation point remains the same, so that this ratio over time becomes large.

In order to ensure that the washing liquid pumped by the respective pump during the first (or second) period does not exceed the respective liquid level in the circulation pumping line or pump-out line and is thus not fed to the washing (or is not pumped out of the washing care appliance) via the inlet element, the respective pump can be activated only briefly, wherein the activation duration (or operation duration) is smaller than the nominal (nominelle) operation duration of the respective pump for circulating pumping (or pumping-out) the washing liquid in the conventional (or nominal) operating situation. Depending on the pumping power of the respective pump, the activation duration may be predetermined for the first (or further) time period. Alternatively, the activation duration may also be determined from the measured pumping power, or the respective pump may be deactivated upon confirmation of reaching the respective liquid level within the first (or second) period of time. The normal operation of the pump is understood to be the condition: in this state, the washing liquid fed by the pump is returned to the lye container during the circulation pumping or is led out of the laundry care appliance during the pumping.

In addition, in order to ensure that the washing liquid pumped by the respective pump reaches the respective liquid level in the circulation pumping line or pump-out line after the first (or second) period of time, the above-mentioned reduced pumping power of the respective pump may in particular be greater than the counter-flow of the washing liquid in the pump-out line or circulation pumping line caused by gravity.

In order to ensure that the washing liquid pumped by the respective pump during the first (or second) time period does not exceed the respective liquid level in the circulation pumping line or pump-out line and is thus not fed to the washing (or is not pumped out of the washing care implement) via the inlet element, the above-mentioned reduced pumping power of the respective pump is in particular smaller than the nominal pumping power of the respective pump for circulating pumping (or pumping out) the washing liquid in the normal (or nominal) operating situation.

In particular, the abovementioned reduced pumping power of the respective pump is sufficient, whereby the pumping pressure exerted by the respective pump on the washing liquid and the counter-flow directed against the washing liquid caused by gravity are in equilibrium at the respective liquid level, so that the liquid column in the respective pressure line can briefly remain at the respective desired maximum liquid level.

In particular, the control device is configured to: when the washing liquid has reached the liquid level in the circulation pumping line or in the pump-out line, the first time period is ended and the other of the pumps is activated during the second time period, and/or the control device is configured in particular for: the second time period ends when the pumped washing liquid has reached the liquid level of the circulation pumping line or the other line corresponding to the pumping line, respectively, i.e. the pumping line or the circulation pumping line.

The detergent dissolution is performed over time until all of the wash substances are completely dissolved in the liquid phase of the wash liquor. In order to evaluate the detergent dissolution time, in particular, the torque-forming drive current or the phase-leg current (phasestrengstrom) of the three-phase synchronous pump drive can be evaluated in addition. In the time-resolved current profile, it can be recognized that: the medium exists in two phases or in a single phase. If the fluid is present in two phases (i.e. the powdered detergent and the washing liquid have not yet formed a solution), a different temporal torque profile will be present in the transport of the mixture than if the fluid is present in a single phase, since the solid phase (in particular the powdered detergent) is already dissolved in the washing liquid when the fluid is present in a single phase. The width of the fluctuations around the average value over time for torque is presented smaller for single phase fluids than for two phase mixtures. Such a representation can also be distinguished if the density difference between the solid phase and the liquid phase is also distinguished more prominently and thus also significantly in the torque profile which is highly resolved over time.

A laundry care appliance is understood to be an appliance (e.g. a washing machine or a washing dryer) used for the care of laundry. In particular, such a laundry care appliance is understood to be a household laundry care appliance. Namely, such laundry care appliances: the laundry care appliance is used in the household category and is used for treating household-used laundry.

In addition, the washing liquid is understood to be such a liquid medium which is fed to a laundry care appliance for treating laundry: the laundry care material (detergent, detergent ingredients, softener, enhancer, etc.) is fed to the liquid medium or the liquid medium already contains the laundry care material. Such a liquid medium is preferably water or an aqueous solution. In particular, the washing liquid is understood not only to be the washing liquid supplied during the washing process time period, but also to be the liquid supplied during other time periods of the laundry care process (for example the soaking time period or the rinsing time period).

In an advantageous embodiment of the laundry care appliance, the pump device has a common suction chamber which is fluidically connected to the discharge line (in particular via the suction line connection), the pump device has a circulation pump pressure chamber which is fluidically connected to the circulation pump line (in particular via the circulation pump pressure line connection), and the pump device has a pump pressure chamber which is fluidically connected to the pump line (in particular via the pump pressure line connection), the circulation pump pressure chamber being fluidically connected to the common suction chamber via the circulation pump suction line connection, the pump pressure chamber being fluidically connected to the common suction chamber via the pump suction line connection, the first pump comprising the pump pressure chamber, and the second pump comprising the circulation pump pressure chamber.

The following technical advantages are achieved: it is ensured that a first pump of the pump device, in particular the evacuation pump, can suck washing liquid from the common suction chamber via the pump-out suction pipe and pump it into the pump-out line via the pump-out pressure chamber, and that a second pump of the pump device can suck washing liquid from the common suction chamber via the circulation-pump-out pipe and pump it into the circulation-pump line via the circulation-pump-out pressure chamber. If the first pump is actuated with the above-described reduced pumping power for the first time during the respective time period, the first pump draws in washing liquid from the discharge line, from the common suction chamber, from the pump-out suction pipe and also from the deactivated pressure line, and pumps the drawn-in washing liquid from the pump-out pressure chamber up to the liquid level in the pump-out line.

If the second pump (in particular the circulation pump) is then operated with the abovementioned reduced pumping power during the respective time period, the second pump sucks back the washing liquid only from the pump-out line on the pressure side and sucks in via the common suction chamber by means of the circulation-pumping suction line and pumps the sucked-in washing liquid via the circulation-pumping pressure chamber up to the liquid level in the circulation-pumping line by means of the circulation-pumping suction line.

The first and second pumps of the pump device may each have a pump drive. Alternatively, the first and second pumps may be realized with only one pump drive, wherein, for example, the circulation pumping may be realized by rotation of the first pump by the pump drive in a first rotational direction and the pumping may be realized by rotation of the second pump by the pump drive in an opposite rotational direction. Such a pump device with two pumps and only one pump drive can advantageously have a common suction chamber with a suction connection and a common pressure chamber, wherein the common pressure chamber can have a pump-out pressure connection and a circulation-pump pressure connection, which are arranged such that the transport of washing liquid via the one or the other pressure connection is dependent on the direction of rotation of the common pump drive. Alternatively, the selection may be made according to the direction of rotation in that blocking devices are provided on the pressure side in the circulation pump delivery route and the pump delivery route. Such a pump device with a single pump drive for the first and second pumps can be realized particularly cost-effectively. Thus, according to the invention, the first pump and the second pump are each understood as such pumps: the pump is arranged for pumping (or for circulating) the washing liquid, wherein the first pump and the second pump may be physically arranged in one or both pump devices.

In an advantageous embodiment of the laundry care appliance, the control device is configured for: the first time period and the second time period following the first time period are repeated after the end of the second time period in order to alternately pump the washing liquid back and forth between the liquid level in the pump-out line and the liquid level in the circulating pump-out line by the pumps of the pump device, wherein the control device is in particular configured for: the first and second time periods are periodically repeated so that the washing liquid is pumped back and forth between the liquid level in the pump-out line and the liquid level in the circulation pumping line by the pumps of the pump device in a periodic manner.

The following technical advantages are achieved: the washing liquid can be carried back and forth between the lines by the pumps a plurality of times by repeating one or more of the first and second time periods. The dissolution efficiency of undissolved laundry care substances can be improved in this way, since not only diffusion processes occur when the laundry care substances are dissolved, but also these diffusion processes are superimposed on convection processes, and thus the dissolution rate can be increased multiple times.

During the reciprocating pumping, the washing liquid does not reach the suction area of the pump device, since the exchange of washing liquid only takes place between the pressure side of the first pump, the pump-out pressure chamber, the pump-out suction pipe, the common suction chamber, the circulation pump-out suction pipe, the circulation pump-out pressure chamber, and the pressure side of the second pump, and therefore the washing liquid no longer flows back into the suction connection of the suction chamber and also into the discharge line.

In an advantageous embodiment of the laundry care appliance, the control device is configured for: after the end of the first or second time period, a subsequent second or first time period is started directly in order to pump washing liquid from the respective pump-out line or circulation pump-out line by the pump of the pump device in a non-intermittent manner and to pump the pumped washing liquid into the respective other line of the pump-out line or circulation pump-out line (i.e. the circulation pump-out line or pump-out line), or the control device is configured to: during the time period between the first and second time periods, and/or during the time period between the second and first time periods, the pump activated during the previous time period is continued to be operated in order to keep the washing liquid at the respective liquid level in the pump-out line or the circulation pump-out line during this time period.

The following technical advantages are achieved: if there is no time section between these time periods, the washing liquid can be pumped back and forth between the pump-out line and the circulation pump-out line in a non-intermittent manner. In contrast, if the washing liquid remains at the respective liquid level during the time period between the above-mentioned time periods, it is possible, for example, to avoid: the washing liquid is reciprocated too rapidly and air may be sucked in association therewith.

In an advantageous embodiment of the laundry care appliance, the control device is configured for: the pumps activated during the first and/or second time periods, respectively, are activated in a periodically staggered manner with reference to the natural period of the column of washing liquid between the pump-out line and the circulation pumping line, which is vibrating at the natural frequency.

The following technical advantages are achieved: by activating the respective pumps in a periodically staggered manner, wobbling (Aufschaukeln) of the oscillating water column caused by resonance effects can be avoided.

In an advantageous embodiment of the laundry care appliance, the column of washing liquid is present between the pump-out line and the circulation pump-out line at a first and a second timeThe segments vibrate at a natural frequency ω, which is given by: omega= (2 g/h) ^1/2 Wherein g is the gravitational acceleration on earth, and wherein h is the height of the respective liquid level in the pump-out line or the circulation pump-out line relative to the zero point of the washing liquid in the respective circulation pump-out line or pump-out line, wherein the control device is configured to: the pumps are alternately activated during the first and second time periods at an activation frequency that is different from the natural frequency of the vibrating wash liquor.

The following technical advantages are achieved: the swaying of the water column caused by resonance is avoided.

In an advantageous embodiment of the laundry care appliance, the control device is configured for: the pumping power of the respective pump is increased to the reduced pumping power directly (in particular with a high gradient of revolutions) at the beginning of the respective time period, so that the washing liquid is delivered without delay at the reduced pumping power at the beginning of the respective time period, or the control device is configured to: the pumping power of the respective pump is continuously (in particular with a small revolution gradient) increased to the above-mentioned reduced pumping power during the pumping period (Pumpzeitraum) at the beginning of the respective period.

The following technical advantages are achieved: depending on the specific requirements, the pumping power of the pump may be increased to the reduced pumping power immediately and without delay, or the pumping power may be increased continuously. In particular, the high revolution gradient comprises a value of 3000/min/s. In particular, the small revolution gradient comprises a value of 250/min/s.

In an advantageous embodiment of the laundry care appliance, the laundry care appliance has a power detection element for detecting an electrical power characteristic of the respective pump, wherein the control device is configured for: comparing the detected electrical power characteristic with a reference power characteristic of the respective pump, wherein the control device is configured to: based on the comparison of the detected electric power characteristic with the reference power characteristic, the corresponding period of time is ended.

The following technical advantages are achieved: the reference power characteristic corresponds here to such a power characteristic of the respective pump: in the case of the power characteristic, the respective pump pumps the washing liquid to the respective liquid level in the pump-out line or the circulation pump-out line. If the detected electrical power characteristic corresponds in particular to the reference power characteristic or is within a tolerance of the reference power characteristic, the control device can recognize that: the washing liquid has reached the respective liquid level and the control means may end the respective time period. Here, it is considered that: if the two-phase medium is still pumped out first and the medium is completely single-phase after the detergent dissolution process, the power requirement changes significantly. Even though the power demand may only slightly change during the detergent dissolution process, however, high frequency fluctuations in motor power may occur due to the presence of the first solid phase in the liquid phase.

In an advantageous embodiment of the laundry care appliance, the laundry care appliance has a power detection element for detecting a further electrical power characteristic of the respective pump, wherein the control device is configured for: comparing the detected further electrical power characteristic with a further reference power characteristic of the respective pump, wherein the control device is configured to: based on a comparison of the detected further electrical power characteristic with the further reference power characteristic, a second pump for pumping the washing liquid is activated with a calibrated pumping power during a third period of time following the second period of time in order to re-feed the washing liquid to the lye container via the circulation pumping line and via the inlet element.

The following technical advantages are achieved: when the laundry care substance is advantageously (in particular completely) dissolved in the washing liquid, it can be identified by a comparison of the detected further electrical power characteristic of the lye pump with the further reference power characteristic. This is the case when the further reference power characteristic corresponds to the detected further electric power characteristic.

In an advantageous embodiment of the laundry care appliance, the power detection element comprises a current sensor for detecting the supply current and/or the torque-forming current of the respective pump.

In an advantageous embodiment of the laundry care appliance, the laundry care appliance has a level sensor for detecting a level of the washing liquid in the circulation pump line, wherein the control device is configured for: when the detected washing liquid level corresponds to the liquid level in the circulation pump line, the respective time period ends and/or the washing care implement has a further level sensor for detecting a further washing liquid level in the pump-out line, wherein the control device is configured for: when the detected level of washing liquid corresponds to the additional level of liquid in the pump-out line, the corresponding period of time ends.

The following technical advantages are achieved: the end of the respective time period can advantageously be indicated to the control device by means of at least one fill level sensor.

According to a second aspect of the invention, the object is achieved by a method for operating a laundry care appliance, wherein the laundry care appliance has an lye container for receiving a washing liquid, wherein the lye container has a discharge opening and an inlet element, wherein the laundry care appliance has: a pump device for pumping washing liquid, a discharge line connecting a discharge opening to the pump device in terms of fluid, a pump-out line connecting the pump device to an outer region of the laundry care appliance in terms of fluid, a circulation pump line connecting the pump device to an inlet element in terms of fluid, and a control device for controlling the pump device, wherein the pump device has a first pump which is configured for: pumping washing liquid (in particular with a calibrated pumping power) out of the lye container via the discharge opening, via the discharge line and via the pump-out line from the laundry care appliance, wherein the pump device has a second pump which is configured for: pumping washing liquid (in particular with a calibrated pumping power) from the lye container via the discharge opening and via the discharge line into the circulation pumping line, and re-feeding washing liquid from the circulation pumping line and via the inlet element into the lye container, wherein the method has the following method steps: one of the pumps of the pump device for pumping washing liquid is activated by the control means (in particular with reduced pumping power) during a first period of time in order to pump washing liquid to the liquid level in the pump-out line or to the liquid level in the circulation pump-out line, and the other of the pumps of the pump device for pumping washing liquid is activated by the control means (in particular with reduced pumping power) during a second period of time immediately following the first period of time in order to pump pumped washing liquid to the liquid level in the pump-out line or the other line (i.e. the circulation pump-out line or the pump-out line) respectively corresponding to the pump-out line or the circulation pump-out line.

The following technical advantages are achieved: a more efficient, faster dissolution of the laundry care substance in the washing liquid can be ensured, since the laundry care substance is not only dissolved by a slower diffusion process, but the process can be superimposed by additional convection.

In an advantageous embodiment of the method, the method has further method steps: reactivating one of the pumps of the pump device for pumping washing liquid with a reduced pumping power by the control device during a first time period immediately following the second time period, in order to pump washing liquid from the respective other of the pump-out line or the circulation-pump-out line (i.e. the circulation-pump-out line or the pump-out line) and to re-pump the pumped washing liquid to the liquid level in the pump-out line or to the liquid level in the circulation-pump-out line; and, the other of the pumps of the pump device for pumping the washing liquid is reactivated with a reduced pumping power by the control device during a second period of time immediately following the first period of time in order to pump the pumped washing liquid to the liquid level in the pump-out line or the respective other line of the circulation pump-out line (i.e. the circulation pump-out line or the pump-out line).

In an advantageous embodiment of the method, the method comprises: the pumping is reciprocally alternated (in particular periodically alternated) between the level of liquid in the pump-out line and the level of liquid in the circulation pumping line, wherein such periodically alternated pumping comprises in particular sinusoidal vibrations.

In an advantageous embodiment of the method, the activation of the respective pump is performed by the control device in a periodically staggered manner with reference to the natural period of the column of washing liquid vibrating at the natural frequency between the pump-out line and the circulation pump-out line.

Drawings

Further embodiments are explained with reference to the accompanying drawings. The drawing shows:

fig. 1 shows a schematic view of a laundry care appliance;

fig. 2 shows a schematic view of a laundry care appliance with a pump device;

FIG. 3 shows a graphical representation of a pumping process of a pump device in a laundry care appliance; and

fig. 4 shows a schematic illustration of a method for dissolving laundry care substances in a laundry care appliance.

Detailed Description

Fig. 1 shows a schematic view of a generic laundry care appliance 100, such as a washing machine for example. The laundry care appliance 100 comprises a wash-in housing 101 into which wash care substances, such as for example detergents, can be injected into the wash-in housing 101. The laundry care appliance 100 comprises a door 103 for loading the laundry care appliance 100 with laundry.

Fig. 2 shows a schematic view of a laundry care appliance with a pump device.

The laundry care appliance 100 has an alkaline container 105 for receiving a wash liquid. The laundry care appliance 100 has a laundry drum 107 for receiving laundry. The lye container 105 has a discharge opening 109 for leading the washing liquid out of the lye container 105. The laundry care appliance 100 has an inlet element 111 (in particular an inlet nozzle), the inlet element 111 being configured for: the circulated pumped washing liquid is supplied to the lye container 105 (or to the laundry received in the laundry drum 107).

The laundry care appliance 100 has a discharge line 113, which discharge line 113 fluidly connects the discharge opening 109 with a pump device 115 for pumping the washing liquid. The laundry care appliance 100 furthermore has a pump-out line 117, which pump-out line 117 connects the pump device 115 to an outer region 119 of the laundry care appliance 100, which is only schematically shown in fig. 2, in terms of fluid technology. The discharge opening 121 of the laundry care appliance 100 is schematically shown here. The laundry care appliance 100 furthermore has a circulation pump line 123, which circulation pump line 123 connects the pump device 115 to the inlet element 111 in terms of fluid technology.

The pump apparatus 115 has a first pump 125-1, the first pump 125-1 being configured to: the washing liquid is pumped out of the laundry care appliance 100 from the lye container 105 via the drain opening 109, via the drain line 113 and via the pump-out line 117 with a calibrated pumping power, in order to remove the spent washing liquid from the laundry care appliance 100 after the washing process over time.

The pump apparatus 115 has a second pump 125-2, the second pump 125-2 being configured to: the washing liquid is pumped from the lye container 105 via the discharge opening 109 via the discharge line 113 into the circulation pumping line 123 with a calibrated pumping power, and the pumped washing liquid is re-fed from the circulation pumping line 123 via the inlet element 111 to the lye container 105 in order to re-wet the washing product with the washing liquid or to re-saturate the already wetted washing product for improving the cleaning process (or washing process) in the category of circulation pumping processes.

As shown in fig. 2, the pump device 115 has a common suction space 127, the suction space 127 being fluidically connected (in particular by means of a suction connection) to the discharge line 113, the pump device 115 having a circulation pump pressure space 129, the circulation pump pressure space 129 being fluidically connected (in particular by means of a circulation pump pressure connection) to the circulation pump line 123, and the pump device 115 having a pump pressure space 131, the pump pressure space 131 being fluidically connected (in particular by means of a pump pressure connection) to the pump line 117. Here, the first pump 125-1 comprises a pump-out pressure chamber 131 and a pump-out suction pipe fitting, which is not shown in particular in fig. 2, and the second pump 125-2 comprises a circulation pump-out pressure chamber 129 and a circulation pump-out suction pipe fitting, which is not shown in particular in fig. 2.

The laundry care appliance 100 furthermore has a control device 133 for controlling the pump device 115, the control device 133 being configured for: either the first pump 125-1 or the second pump 125-2 of the pump apparatus 115 for pumping the washing liquid is activated.

During the laundry care course, a user gives a laundry care substance, such as a detergent, to the laundry care appliance 100, which is not shown in fig. 2, into the wash-in housing 101. The water is led into the flush-in housing 101 by means of the solenoid valve via the domestic water connection of the laundry care appliance 100, wherein the laundry care substance is fed together with the water via an injection line, not shown in fig. 2, to the lye container 105 and accumulates in the lower region of the lye container 105 in the vicinity of the discharge opening 109.

During the washing process, the laundry drum 107 is moved and the dissolution of the laundry care substances is caused mainly by diffusion processes and convection processes (due to the drum rotation), whereby a uniform washing liquid is obtained relatively time-consuming. Because undissolved highly concentrated laundry care material on the laundry may cause discoloration damage, rapid and complete dissolution of the laundry care material is necessary, for example, in order not to cause damage to the laundry during the washing process when the user is not properly feeding the laundry care material into the wash-in housing 101 (e.g., overdosing).

In a conventional laundry care appliance 100 without a circulation pumping system, an alkaline liquor container seal is usually arranged on the discharge opening 109, which prevents an unintentional outflow of washing liquor from the alkaline liquor container 105 via the discharge opening 109, whereby, without a circulation pumping system, laundry care substances may be lost and the washing process performed can no longer have a predictable washing result.

In the circulation pumping system shown in fig. 2, the lye container seals are generally eliminated and the loss of laundry care substances is compensated for by the design of the washing technique (e.g. by additional components) to ensure an advantageous washing result. For this purpose, the detergent which has been dissolved in the washing liquid is fed to the laundry again and again by the circulation function by activation of the circulation pump.

The control device 133 is configured to: one of the pumps 125-1,125-2 of the pump device 115 for pumping washing liquid is activated with reduced pumping power during the first period of time in order to pump washing liquid to the liquid level 135-1 in the pump-out line 117 or to the liquid level 135-2 in the circulation pumping line 123.

The control device 133 is configured to: the other one of the pumps 125-1,125-2 in the pump device 115 for pumping washing liquid is activated with a reduced pumping power in a second period of time immediately following the first period of time in order to pump washing liquid from the respective pump-out line 117 or circulation-pump-out line 123 and to pump the pumped washing liquid to the liquid level 135-1,135-2 in the respective other line of the pump-out line 117 or circulation-pump-out line 123, i.e. the circulation-pump-out line 123 or pump-out line 117.

Thus, by activation of the two pumps 125-1,125-2 of the pump device 115 over time, the washing liquid located in the discharge line 113 is pumped back and forth between the circulation pumping line 123 and the pump out line 117, so that the diffusion dissolution process of the laundry care material is considerably accelerated by corresponding convection. Here, the washing liquid pumped back and forth flows through the pressure chambers 129,131 and the common suction chamber 127 of the pump device 115, in particular between the circulation pump line 123 and the pump-out line 117, whereas the washing liquid pumped back and forth here cannot enter the lye container 105 via the discharge opening 109, so that undissolved laundry care substances can be prevented from coming into contact with the laundry in the laundry drum 107 during the dissolving process.

Here, however, unlike the pump-out process (or the circulation pumping process), the respective pumps 125-1,125-2 are operated with reduced pumping power, thereby ensuring that: the washing liquid pumped by the first pump 125-1 is pumped only to the liquid level 135-1 in the pump-out line 117 and not to be pumped out of the washing care implement 100 via the discharge opening 121 beyond this liquid level 135-1, and the washing liquid pumped by the second pump 125-2 is pumped only to the liquid level 135-2 in the circulation-pumping line 123 and not to be fed to the washing in the washing drum 107 via the inlet element 111 beyond this liquid level 135-2.

In one embodiment, the control device 133 is configured to: the first pump 125-1 of the pump device 115 for pumping washing liquid is activated with reduced pumping power for a first period of time in order to pump washing liquid to the liquid level 135-1 in the pump-out line 117, and the control means 133 are configured for: the second pump 125-2 of the pump device 115 for pumping washing liquid is activated with a reduced pumping power during a second period of time, which follows the first period of time, in order to pump washing liquid from the pump-out line 117 and to pump the pumped washing liquid to the liquid level 135-2 in the circulation-pumping line 123.

In one other embodiment, the control device 133 is configured to: the second pump 125-2 of the pump device 115 for pumping washing liquid is activated with reduced pumping power during the first period of time in order to pump washing liquid to the liquid level 135-2 in the circulation pumping line 123, and the control means 133 are configured for: the first pump 125-1 of the pump device 115 for pumping washing liquid is activated with a reduced pumping power during a second period of time immediately following the first period of time in order to pump washing liquid from the circulation pumping line 123 and to pump the pumped washing liquid to the liquid level 135-1 in the pump out line 117.

In order to prevent washing liquid from being pumped out of the discharge opening 121, the liquid level 135-1 in the pump-out line 117 is located in particular below the discharge opening 121. If the pump-out line 117 has a section extending over the outlet opening 121, the liquid level 135-1 is located in particular below the section of the pump-out line 117 extending over the outlet opening 121.

In order to prevent the re-feeding of washing liquid to the washing via the inlet element 111, the liquid level 135-2 in the circulation pumping line 123 is located in particular below the inlet element 111. If the circulation pumping line 123 has a section extending above the inlet element 111, the liquid level 135-2 is located in particular below the section of the circulation pumping line 123 extending above the inlet element 111.

In order to ensure a particularly advantageous dissolution process of the laundry care substance, the control device 133 is configured to: the first time period and the second time period following the first time period are repeated after the end of the second time period, wherein the control device 133 is configured in particular for: the first and second time periods are repeated periodically in time.

Thus, the control means 133 alternately activates the first and second pumps 125-1,125-2 of the pump device 115 to reciprocally pump (especially periodically reciprocally pump) the wash liquid between the liquid level 135-1 in the pump-out line 117 and the liquid level 135-2 in the circulation-pumping line 123, whereby an advantageous dissolution of the laundry care substance can be ensured.

The control device 133 is particularly configured for: the subsequent second or first time period is started directly after the end of the first or second time period so that no washing liquid is intermittently pumped by the pumps 125-1,125-2 of the pump device 115 from the respective pump-out line 117 or the circulation-out line 123 and the pumped washing liquid is pumped into the respective other line of the pump-out line 117 or the circulation-out line 123 (i.e. the circulation-out line 123 or the pump-out line 117).

Alternatively, the control device 133 is configured in particular for: during the time period between the first and second time periods, and/or during the time period between the second and first time periods, the pump 125-1,125-2 activated during the previous time period is continuously operated in order to keep the washing liquid at the respective liquid level 135-1,135-2 in the pump-out line 117 or the circulation pump-out line 123 during said time period. By the respective corresponding further pump 125-1,125-2 being activated in a delayed manner during the subsequent second (or first) time period on the basis of the above-mentioned time period, undesired resonance of the oscillating column of washing liquid between the pump-out line 117 and the circulation pump-out line 123 can be counteracted.

In particular, the control device 133 is configured to: the pump 125-1,125-2, which is activated during the first and/or second time period, respectively, is activated in a periodically staggered manner with reference to the natural period of the column of washing liquid vibrating at the natural frequency between the pump-out line 117 and the circulation pumping line 123.

In particular, a column of washing liquidVibration occurs between pump-out line 117 and circulation pump-out line 123 during the first and second time periods at a natural frequency ω, which is given by the following equation: omega= (2 g/h) ^1/2 Where g is the gravitational acceleration on earth, and where h is the height of the respective liquid level 135-1,135-2 in the pump-out line 117 or the circulation pump-out line 123 relative to the respective circulation pump-out line 123 or the washing liquid zero point in the pump-out line 117, where the control device 133 is configured to: these pumps 125-1,125-2 are alternately activated during the first and second time periods at an activation frequency that is different from the natural frequency of the vibrating wash liquor.

The control device 133 is configured to: the pumping power of the respective pump 125-1,125-2 is increased directly (in particular with a high revolution gradient) to the reduced pumping power at the beginning of the respective time period, so that the washing liquid is pumped without delay at the reduced pumping power at the beginning of the respective time period.

Alternatively, the control device 133 is configured to: the pumping power of the respective pump 125-1,125-2 is continuously (in particular with a small revolution gradient) increased to the above-mentioned reduced pumping power during the pumping period at the beginning of the respective period. In particular, the reduced pumping power is greater than the counter flow of the washing liquid in the pump-out line 117 or the circulation pumping line 123 caused by gravity, since the flow in the system with vibration energy is frictional.

The laundry care appliance 100 has, in particular, a power detection element 137 for detecting the electrical power characteristic of the respective pump 125-1,125-2, wherein the control device 133 is configured to: the detected electrical power characteristic is compared with a reference power characteristic of the respective pump 125-1,125-2, wherein the control device 133 is configured to: based on the comparison of the detected electric power characteristic with the reference power characteristic, the corresponding period of time is ended. The power characteristics may include, for example, a supply current and/or a motor torque of the respective pump motor.

The reference power characteristics correspond here to such power characteristics of the respective pumps 125-1, 125-2: in the case of the power characteristic, the respective pump 125-1,125-2 pumps the washing liquid to the respective liquid level 135-1,135-2 in the pump-out line 117 or the circulation pump-out line 123. If the detected electrical power characteristic corresponds in particular to the reference power characteristic or is within a tolerance of the reference power characteristic, the control device 133 can recognize that: the washing liquid has reached the respective liquid level 135-1,135-2 and the control means 133 may end the respective time period.

The power detection element 137 is furthermore designed in particular for detecting a further electrical power characteristic of the respective pump 125-1, 125-2. Here, the control device 133 is configured to: the detected further electrical power characteristic is compared with a further reference power characteristic of the respective pump 125-1, 125-2. The control device 133 is particularly configured for: based on a comparison of the detected further electrical power characteristic with the further reference power characteristic, the second pump 125-2 for pumping the washing liquid is activated with a calibrated pumping power during a third time period following the second time period in order to pump the washing liquid into the circulation pumping line 123 via the drain opening 109 and via the drain line 113 and to re-feed the washing liquid pumped into the circulation pumping line 123 to the lye container 105 via the inlet element 111.

Here, the power detection element 137 has identified such a power threshold: at this power threshold, the initially undissolved two-phase washing liquid comprising solid, powdery washing additive and liquid fluid is finally present entirely in a single phase and can be fed without problems to the washing batch without risking discoloration of the laundry.

Since there is a high time resolution in the motor torque detection (i.e. in the detection of the current forming the torque), it can be detected by the power detection element 137 by means of a further power characteristic: whether there is still undissolved residue of the laundry care material (e.g., powdery residue of detergent) in the wash liquid pumped by the pump device 115. When the laundry care substance has been completely dissolved in the washing liquid, the control device 133 can be identified by a comparison of the detected further electrical power characteristic of the respective pump 125-1,125-2 with the further reference power characteristic of the respective pump 125-1, 125-2.

If the detected further electrical power characteristic corresponds to the further reference power characteristic, the control device 133 can operate the second pump 125-2 at the nominal pumping power for a subsequent third period of time after the end of the second period of time and ensure an effective supply of washing liquid into the lye container 105 via the inlet element 111 in the course of the circulation pumping process.

In one embodiment, the laundry care appliance 100 has in particular a level sensor for detecting the level of the washing liquid in the circulation pump line 123, wherein the control device 133 is configured for: when the detected washing liquid level corresponds to the liquid level 135-2 in the circulation pump line 123, the respective time period ends and/or the laundry care appliance 100 has, in particular, a further level sensor for detecting a further washing liquid level in the pump-out line 117, wherein the control device 133 is configured to: when the detected level of wash liquid corresponds to the level 135-1 of liquid in the pump-out line 117, the corresponding period of time ends.

By alternately pumping (or transporting back) the wash liquor by the pump device 115 during the first (or second) time period, an advantageous dissolution of the laundry care substance in the wash liquor is achieved. Thus, damage to the laundry caused by undissolved laundry care substances can be avoided in the case of improper dosing of the laundry care substances.

Fig. 3 shows a graphical representation of the pumping process of a pump device in a laundry care appliance.

Diagram (a) of fig. 3 shows the pumping power of the second pump 125-2 (in particular the circulation pump) of the pump device 115 along the ordinate axis 139, wherein the pumping power is shown on the basis of time, which is given along the abscissa axis 141. Diagram (b) of fig. 3 shows the pumping power of the first pump 125-1 (in particular the pump-out pump) of the pump device 115 along the ordinate axis 139, wherein the pumping power is shown on the basis of time, which is given along the abscissa axis 141.

Diagram (c) of fig. 3 shows the height of the wash liquid column in the fluidly connected circulation pumping line 123 with the second pump 125-2 along the ordinate axis 139, wherein the height is shown on the basis of time, which is given along the abscissa axis 141. Along a further ordinate axis 140, diagram (c) of fig. 3 shows the height of the washing liquid column in the pump-out line 117 fluidically connected to the first pump 125-1, wherein this height is shown on the basis of time, which is given along the abscissa axis 141.

During the first time period 143-1, the second pump 125-2 is activated by the control device 133 of the washware care implement 100 and washware is pumped into the circulation pumping line 123 with reduced pumping power 145-1 until the level of washware in the circulation pumping line 123 reaches the liquid level 135-2 in the circulation pumping line 123.

During a second time period 143-2, which follows the first time period 141, the second pump 125-2 is deactivated and the first pump 125-1 is activated, and the wash liquid is pumped into the pump-out pump 117 with a reduced pumping power 145-1 until the wash liquid level in the pump-out line 117 reaches the liquid level 135-1 in the pump-out line 117.

The first time period 143-1 follows the second time period 143-2 and the second time period 143-2 follows the first time period 143-1, wherein the control device 133 repeats the time periods 143-1,143-2, in particular for a long time, until the laundry care substance is completely dissolved or until the time periods 143-1,143-2 are stopped after a defined number of repetitions.

As a first method step, the method 200 comprises: one of the pumps 125-1,125-2 of the pump device 115 for pumping washing liquid is activated 201 by the control means 133 with a reduced pumping power 145-1 during the first period 143-1 in order to pump washing liquid to the liquid level 135-1 in the pump-out line 117 or to the liquid level 135-2 in the circulation pumping line 123.

As a second method step, the method 200 comprises: the further one of the pumps 125-1,125-2 of the pump device 115 for pumping washing liquid is activated 203 by the control device 133 with a reduced pumping power 145-1 in a second time period 143-2 following the first time period 143-1 in order to pump the pumped washing liquid to the liquid level 135-1,135-2 in the pump-out line 117 or in the respective other line of the circulation-pump-out line 123 (i.e. the circulation-pump-out line 123 or the pump-out line 117).

All the features explained and shown in connection with the individual embodiments of the invention can be arranged in different combinations in the subject matter according to the invention in order to achieve their advantageous effects at the same time.

The scope of the invention is defined by the claims and is not limited by the features explained in the description or shown in the drawings.

List of reference numerals

100. Washing care implement

101. Is punched into the shell

103. Door

105. Alkali liquor container

107. Washing drum

109. Discharge opening

111. Inlet element

113. Discharge pipeline

115. Pump device

117. Pump-out line

119. Outer region

121. Discharge opening

123. Circulation pumping pipeline

125-1 first pump

125-2 second pump

127. Common suction chamber

129. Circulating pump pressure chamber

131. Pump-out pressure chamber

133. Control device

135-1 level of liquid in the pump-out line

135-2 level of liquid in the circulation pumping line

137. Power detection element

139. Ordinate axis

140. Additional ordinate axis

141. Axis of abscissa

143-1 first time period

143-2 second time period

145-1 reduced pumping power

200. Method for dissolving laundry care materials

201. The first method step: activating one of the pumps

203. The second method step: activating another of the pumps

Claims

1. A laundry care appliance (100) having:

An alkaline solution container (105) for receiving a washing solution,

wherein the lye container (105) has a discharge opening (109) and an inlet element (111),

pump means (115) for pumping the washing liquid,

-a discharge line (113) fluidly connecting the discharge opening (109) with the pump device (115),

a pump-out line (117) which fluidically connects the pump device (115) to an outer region (119) of the laundry care appliance (100),

wherein the pump device (115) has a first pump (125-1) which is configured for: pumping wash liquor from the lye container (105) via the discharge opening (109), via the discharge line (113) and via the pump-out line (117) out of the laundry care appliance (100), and

control means (133) for controlling said pump device (115),

wherein the control device (133) is configured to: activating a first pump (125-1) of the pump device (115) for pumping washing liquid in order to pump washing liquid up to a liquid level (135-1) in the pump-out line (117),

it is characterized in that the method comprises the steps of,

the laundry care appliance (100) is designed with a circulation pump line (123) which fluidically connects the pump device (115) to the inlet element (111),

Wherein the pump device (115) has a second pump (125-2) which is configured for: pumping washing liquid from the lye container (105) via the discharge opening (109) and via the discharge line (113) into the circulation pumping line (123), and re-feeding the washing liquid from the circulation pumping line (123) and via the inlet element (111) to the lye container (105),

the control device (133) is configured to: activating one of the above pumps of the pump device (115) in a first time period (143-1) for pumping wash liquid, for pumping wash liquid up to a liquid level (135-1) in the pump-out line (117) or up to a liquid level (135-2) in the circulation pump-out line (123), and

the control device (133) is configured to: activating the other of the above-mentioned pumps of the pump device (115) for pumping washing liquid in a second time period (143-2) immediately following the first time period (143-1) for pumping washing liquid from the respective pump-out line (117) or circulation pump-out line (123) and pumping the pumped washing liquid up to the liquid level in the respective pump-out line (117) or the respective other line of the circulation pump-out line (123),

Wherein the control device (133) is configured to: deactivating a pump of the pump device (115) used in the first time period (143-1) in a second time period (143-2) immediately following the first time period,

the control device (133) is configured to: -repeating the first time period (143-1) and a second time period (143-2) immediately following the first time period (143-1) after the end of the second time period (143-2) so as to alternately pump washing liquid back and forth between the liquid level (135-1) in the pump-out line (117) and the liquid level (135-2) in the circulation pumping line (123) by the above-mentioned pump of the pump device (115).

2. The laundry care appliance (100) of claim 1,

it is characterized in that the method comprises the steps of,

the first pump (125-1) is configured for: pumping wash liquor from the lye container (105) via the pump-out line (117) from the laundry care appliance (100) with a calibrated pumping power,

the second pump (125-2) is configured to: re-feeding washing liquid from the lye container (105) to the lye container (105) via the inlet element (111) with a calibrated pumping power,

the control device (133) is configured to: activating one of the above pumps of the pump device (115) with reduced pumping power (145-1) for the first time period (143-1) for pumping the washing liquid, and

The control device (133) is configured to: activating another one of the above pumps of the pump device (115) with a reduced pumping power (145-1) for pumping washing liquid during the second time period (143-2).

3. The laundry care appliance (100) according to claim 1 or 2,

it is characterized in that the method comprises the steps of,

the pump device (115) has a common suction chamber (127) which is fluidically connected to the discharge line (113),

the pump device (115) has a circulation pump pressure chamber (129) which is fluidically connected to the circulation pump line (123) and

the pump device (115) has a pump-out pressure chamber (131) which is fluidically connected to the pump-out line (117),

wherein the circulating pump pressure chamber (129) is fluidically connected to the common suction chamber (127) by a circulating pump suction pipe,

wherein the pump-out pressure chamber (131) is fluidically connected to the common suction chamber (127) by a pump-out suction line,

wherein the first pump (125-1) comprises the pump-out pressure chamber (131), and

wherein the second pump (125-2) comprises the circulation pumping pressure chamber (129).

4. The laundry care appliance (100) according to claim 1 or 2,

it is characterized in that the method comprises the steps of,

the pump device (115) has a common suction chamber (127) which is connected to the discharge line (113) by a suction pipe connection,

the pump device (115) has a circulation pump pressure chamber (129) which is connected to the circulation pump line (123) by a circulation pump pressure line connection and

the pump device (115) has a pump-out pressure chamber (131) which is connected to the pump-out line (117) via a pump-out pressure pipe connection.

5. The laundry care appliance (100) according to claim 1 or 2,

it is characterized in that the method comprises the steps of,

the control device (133) is configured to: -repeating the first time period (143-1) and the second time period (143-2) periodically so as to periodically and alternately pump washing liquid back and forth between the liquid level (135-1) in the pump-out line (117) and the liquid level (135-2) in the circulation pumping line (123) by the above-mentioned pump of the pump device (115).

6. The laundry care appliance (100) according to claim 1 or 2,

it is characterized in that the method comprises the steps of,

the control device (133) is configured to: directly starting a subsequent second time period (143-2) or first time period (143-1) after the end of the first time period (143-1) or second time period (143-2) so as to pump the washing liquid from the respective pump-out line (117) or circulation pump-out line (123) in a non-intermittent manner through the above-mentioned pump of the pump device (115) and pump the pumped washing liquid into the respective other line of the pump-out line (117) or the circulation pump-out line (123), or

The control device (133) is configured to: during a time period between the first time period (143-1) and the second time period (143-2) and/or during a time period between the second time period (143-2) and the first time period (143-1), the pump activated during the previous time period is continued to be operated in order to keep the washing liquid at the respective liquid level in the pump-out line (117) or the circulation pump-out line (123) during this time period.

7. The laundry care appliance (100) according to claim 1 or 2,

it is characterized in that the method comprises the steps of,

the column of washing liquid vibrates between the pump-out line (117) and the circulation pumping line (123) during the first time period (143-1) and the second time period (143-2) with a natural frequency ω, which is derived by the following formula: omega= (2 g/h) ^1/2 ，

Where g is the gravitational acceleration on earth, an

Wherein h is the height of the respective liquid level in the pump-out line (117) or the circulation pump-out line (123) relative to the zero point of the washing liquid in the respective circulation pump-out line (123) or pump-out line (117),

wherein the control device (133) is configured to: the pump is alternately activated at an activation frequency during the first time period (143-1) and the second time period (143-2), the activation frequency being different from the natural frequency of the washing liquid in which the vibration occurs.

8. The laundry care appliance (100) according to claim 2,

it is characterized in that the method comprises the steps of,

the control device (133) is configured to: the pumping power of the respective pump is increased to the reduced pumping power (145-1) directly at the beginning of the respective time period with a high revolution gradient, so that the washing liquid is fed at the reduced pumping power (145-1) without delay at the beginning of the respective time period, or

The control device (133) is configured to: the pumping power of the respective pump is continuously increased to said reduced pumping power (145-1) with a small revolution gradient during the pumping period at the beginning of the respective period.

9. The laundry care appliance (100) according to any one of claims 1, 2, 8,

it is characterized in that the method comprises the steps of,

the laundry care appliance (100) has a power detection element (137) for detecting an electrical power characteristic of the respective pump,

wherein the control device (133) is configured to: the detected electrical power characteristic is compared with a reference power characteristic of the corresponding pump,

wherein the control device (133) is configured to: based on the comparison of the detected electric power characteristic with the reference power characteristic, the corresponding period of time is ended.

10. The laundry care appliance (100) according to any one of claims 1, 2, 8,

it is characterized in that the method comprises the steps of,

the laundry care appliance (100) has a power detection element (137) for detecting a further electrical power characteristic of the respective pump,

wherein the control device (133) is configured to: the detected further electrical power characteristic is compared with a further reference power characteristic of the respective pump,

wherein the control device (133) is configured to: based on a comparison of the detected further electrical power characteristic with the further reference power characteristic, the second pump (125-2) is activated with a calibrated pumping power during a third time period following the second time period (143-2) for pumping washing liquid for re-feeding washing liquid to the lye container (105) via the circulation pumping line (123) and via the inlet element (111).

11. The laundry care appliance (100) of claim 9,

it is characterized in that the method comprises the steps of,

the power detection element (137) comprises a current sensor for detecting a supply current and/or a torque forming current of the respective pump (125-1, 125-2).

12. The laundry care appliance (100) according to any one of claims 1, 2, 8, 11,

It is characterized in that the method comprises the steps of,

the laundry care appliance (100) has a level sensor for detecting a level of the washing liquid in the circulation pumping line (123), wherein the control device (133) is configured for: ending the corresponding time period when the detected level of washing liquid corresponds to the level (135-2) of liquid in the circulation pumping line (123), and/or

The laundry care appliance (100) has a further level sensor for detecting a further level of washing liquid in the pump-out line (117), wherein the control device (133) is configured for: when the detected level of washing liquid corresponds to the further level of liquid (135-1) in the pump-out line (117), the corresponding time period ends.

13. A method (200) for operating a laundry care appliance (100),

wherein the laundry care appliance (100) has an alkaline solution container (105) for receiving a washing solution,

wherein the laundry care appliance (100) has:

pump means (115) for pumping the washing liquid,

control means (133) for controlling said pump device (115),

wherein the method (200) comprises the steps of:

activating (201) a first pump (125-1) of the pump device (115) for pumping washing liquid in order to pump washing liquid up to a liquid level (135-1) in the pump-out line (117),

it is characterized in that the method comprises the steps of,

wherein the laundry care appliance (100) has a circulation pump line (123) which fluidically connects the pump device (115) with the inlet element (111) and

The method (200) has the following method steps:

-activating (201), by means of the control device (133), one of the above-mentioned pumps of the pump arrangement (115) for pumping washing liquid up to a liquid level (135-1) in the pump-out line (117) or up to a liquid level (135-2) in the circulation-pumping line (123) in a first period (143-1), and

-activating (203), by means of the control device (133), another one of the pumps of the pump device (115) for pumping washing liquid in a second time period (143-2) immediately following the first time period (143-1) so as to pump the pumped washing liquid up to a liquid level in the pump-out line (117) or the respective other line of the circulation pump-out line (123),

-in a second time period (143-2) following the first time period (143-1), disabling the pump of the pump device (115) used in the first time period by the control means (133),

-pumping alternately back and forth between a liquid level (135-1) in the pump-out line (117) and a liquid level (135-2) in the circulation pumping line (123).

14. The method (200) of claim 13,

It is characterized in that the method comprises the steps of,

the second pump (125-2) is configured to: re-feeding washing liquid from the lye container (105) to the lye container (105) via the inlet element (111) with a calibrated pumping power, and

the method (200) has further method steps:

-activating (201), by means of the control device (133), one of the above-mentioned pumps of the pump device (115) with reduced pumping power (145-1) for pumping washing liquid, and during the first time period (143-1), and

-activating (203), by the control means (133), another of the above-mentioned pumps of the pump device (115) with reduced pumping power (145-1) for pumping wash liquid in a second time period (143-2) immediately following the first time period (143-1).

15. The method (200) according to claim 13 or 14,

it is characterized in that the method comprises the steps of,

the method (200) has further method steps:

-in a first time period (143-1) immediately following the second time period (143-2), reactivating (205), by the control device (133), one of the pumps of the pump apparatus (115) for pumping washing liquid, in order to pump washing liquid from the pump-out line (117) or the respective other line of the circulation pump-out line (123), and re-pumping the pumped washing liquid up to a liquid level (135-1) in the pump-out line (117) or up to a liquid level (135-2) in the circulation pump-out line (123); and is also provided with

-reactivating (207) by the control device (133) another one of the pumps of the pump device (115) for pumping washing liquid in a second time period (143-2) immediately following the first time period (143-1) for pumping the pumped washing liquid up to a liquid level in the pump-out line (117) or the respective other line of the circulation pump-out line (123).

16. The method (200) according to claim 13 or 14,

it is characterized in that the method comprises the steps of,

the method (200) comprises: -periodically and alternately pumping between a liquid level (135-1) in the pump-out line (117) and a liquid level (135-2) in the circulation pumping line (123), wherein the periodically and alternately pumping comprises sinusoidal vibrations.

17. The method (200) according to claim 13 or 14,

it is characterized in that the method comprises the steps of,

the activation (201, 203, 205, 207) of the respective pumps is performed by the control device (133) in a periodic staggered manner with reference to the natural period of the column of washing liquid vibrating at the natural frequency between the pump-out line (117) and the circulation pump-out line (123).