CN115698412A

CN115698412A - Method for controlling a washing machine and washing machine

Info

Publication number: CN115698412A
Application number: CN202080100214.XA
Authority: CN
Inventors: 保罗·德留西
Original assignee: Electrolux Appliances AB
Current assignee: Electrolux Appliances AB
Priority date: 2020-04-30
Filing date: 2020-04-30
Publication date: 2023-02-03
Also published as: WO2021219226A1; EP4143375A1

Abstract

The invention relates to a method for operating a washing machine (10) comprising: a washing tub (30); one or more electrovalves (70) through which liquid is admitted into the washing tub (30); a liquid level detector (100) configured for detecting a quantity indicative of a liquid level within the washing tub (30); a drain pump (92) configured to drain liquid from the washing tub (30); a plurality of further electrical loads (50, 51, 52, 53); a control unit (200) configured for controlling the one or more electronic valves (70), the liquid level detector (100), the drain pump (92), and the plurality of further electrical loads (50, 51, 52, 53), wherein the method comprises: placing the washing machine (10) in a standby state in which the one or more electronic valves (70) and one or more of the plurality of further electrical loads (50, 51, 52, 53) are disconnected from the electrical power supply, wherein the method comprises the steps of: -supplying power to the liquid level detector (100) for at least a first on-time interval (tON 1) when the washing machine (10) is in the standby state; -detecting, by the liquid level detector (100), a first value (L1) indicative of the amount of liquid level inside the washing tub (30) during the first on-time interval (tON 1); -if the first value (L1) satisfies a first predetermined condition, activating the drain pump (92) to drain liquid from the washing tub (30) and/or generating an alarm. The invention also relates to a washing machine (10) configured for implementing the method.

Description

Method for controlling a washing machine and washing machine

The present invention relates to a method for controlling a washing machine, such as a washing machine or a dishwasher, and to a washing machine configured to implement the method.

Nowadays, washing machines, such as washing machines and dishwashers, comprise a washing tub in which the articles to be washed can be loaded via an access opening which can be closed by a door or porthole.

In particular, in known laundry washing machines, the items to be washed (i.e. the laundry) are loaded in a rotating drum contained within a washing tub, and in known dishwashing machines, the items to be washed (i.e. the crockery or the dishes) are generally loaded within a rack removably mounted in the washing tub.

Known washing machines typically comprise a plurality of electrical loads ((user interface(s), (pump(s), (valve(s), (motor (s)), etc.), and an electronic control unit configured for controlling such electrical loads, in particular during a washing cycle.

In known washing machines, water enters the tub through a water supply circuit connected to a water delivery mains external to the machine; the water may be mixed with wash and/or rinse additives and/or may be heated to a desired temperature before or after entering the tub.

Typically, the water supply circuit comprises one or more electronic valves controlled by the control unit to selectively regulate the entry of water from the water delivery means.

After the washing cycle, the washing liquid (i.e. water, or water mixed with the wash/rinse additive (s)) is drained from the tub through a drain circuit, which typically comprises a drain pump controlled by the control unit.

Today, in order to reduce the power consumption, most known washing machines are configured in such a way that after a washing cycle and/or when the washing machine has been inoperative for a certain period of time, these washing machines are automatically put into a "standby state", i.e. a state in which all or most of their electrical loads are not powered.

In fact, it is known that many electrical loads, when powered (i.e. when electrically connected to a power supply), absorb electrical power even when not in operation, and therefore the only way to completely eliminate their absorption of electrical power is to temporarily cut off the power supply (i.e. disconnect them from the power supply).

In known washing machines, sometimes the electrovalve(s) of the water supply circuit may start to leak, so that water coming from the water delivery mains outside the machine may enter the washing tub and accumulate at the bottom thereof. If the washing machine is used frequently, the user may not notice the leakage, since many washing cycles now start with draining of possible residual liquid from the bottom of the washing tub.

Furthermore, in most known washing machines, during the washing cycle, the liquid level inside the tub is monitored by a level detection device, and the control unit is typically configured for generating an alarm message (for example, a specific sound) and/or interrupting the washing cycle in case the water level inside the tub is higher than expected, which may occur in case of leakage of the electrovalve.

In any case, such level control is at most effective during the washing cycle and not, for example, when the washing machine is in the above-mentioned standby state.

Therefore, the following problems exist in the known washing machine:

when the washing machine is in a standby state, it is difficult for the user to notice a leak, and therefore the water level inside the tub rises until it overflows outside the washing machine, for example via an opening for loading the items to be washed into the washing tub (if the door or porthole of the machine is open), and/or via other openings connecting the inside of the washing tub with the outside environment (for example, an air gap provided in the washing machine for preventing liquid from possibly flowing back from the washing tub to a water delivery mains fluidly connected to the washing machine).

It is therefore an object of the present invention to provide a solution for avoiding that liquid may overflow from the tub of a washing machine (e.g. washing machine, washer-dryer, dishwasher) when the washing machine is in a standby state (in which at least some of the electrical loads are not powered).

The applicant has found that by activating a liquid level detector of the washing machine when the washing machine is in a standby state, it is possible to detect an abnormal increase of the liquid level inside the washing tub during such a standby state and consequently activate the drain pump and/or generate an alarm to reduce the risk that liquid may overflow from the washing machine.

In particular, the above object is solved by a method for operating a washing machine comprising: a washing tub; one or more electronic valves through which liquid is admitted into the washing tub; a liquid level detector configured to detect an amount indicative of a liquid level within the washing tub; a drain pump configured to drain liquid from the washing tub; a plurality of further electrical loads; a control unit configured to control the one or more electronic valves, the liquid level detector, the drain pump, and the plurality of additional electrical loads, wherein the method comprises: placing the washing machine in a standby state in which the one or more electrovalves and one or more of the plurality of further electrical loads are disconnected from the power supply, wherein the method comprises the steps of:

-powering the level detector for at least a first on-time interval when the washing machine is in the standby state;

-detecting, by the liquid level detector, a first value indicative of the amount of liquid level inside the washing tub during the first on-time interval;

-activating the drain pump to drain liquid from the washing tub and/or generating an alarm if the first value fulfils a first predetermined condition.

In a preferred embodiment, the first predetermined condition on the first value comprises reaching or exceeding a predetermined first threshold value.

In a preferred embodiment, the first on-time interval is between 5 seconds and 15 seconds.

More preferably, the first on time interval is 10 seconds.

In an advantageous embodiment, the method comprises: when the washing machine is in a standby state and after a phase of supplying power to the level detector for at least a first on-time interval, the following phases are carried out:

-disconnecting the liquid level detector from the power supply for a first off time interval.

Preferably, the first off-time interval is between 50 seconds and 70 seconds.

More preferably, the first off time interval is 60 seconds.

In an advantageous embodiment, the method comprises:

-detecting or estimating a starting value indicative of a quantity of liquid level inside the washing tub at the beginning of the standby state;

-comparing the first value with a starting value;

-activating the discharge pump if the difference between the first value and the starting value reaches or exceeds a predetermined second threshold value.

In a further advantageous embodiment, the method comprises: when the washing machine is in a standby state and after a phase of supplying power to the level detector for at least a first on-time interval, the following phases are carried out:

-powering the level detector for a second on-time interval when the washing machine is in the standby state;

-detecting, by the level detector, a second value indicative of the amount of liquid level inside the washing tub during a second opening time interval;

-comparing the second value with the first value;

-activating a drain pump and/or generating an alarm if the difference between the second value and the first value meets or exceeds a predetermined third threshold.

Preferably, the phase of disconnecting the level detector from the power supply for the first off time interval is performed between the step of supplying power to the level detector for the first on time interval and the phase of supplying power to the level detector for the second on time interval.

Preferably, the method comprises: when the washing machine is in a standby state and after a phase of supplying power to the level detector for a second on-time interval, the following phases are carried out:

-disconnecting the liquid level detector from the power supply for a second off time interval.

In a preferred embodiment, the second off time interval is between 50 seconds and 70 seconds.

More preferably, the second off time interval is 60 seconds.

In a preferred embodiment, the phase of supplying power to the level detector for at least a first on-time interval when the washing machine is in the standby state is carried out after a predetermined first delay time has elapsed since the washing machine has been placed in the standby state, during which the level detector is disconnected from the power supply.

Preferably, the first delay time is between 50 seconds and 70 seconds.

More preferably, the first delay time is 60 seconds.

In a further advantageous embodiment, the phase of supplying power to the level detector for at least the first on-time interval is started simultaneously with placing the washing machine in a standby state.

In a preferred embodiment, the phase of supplying power to the level detector for at least a second on-time interval when the washing machine is in the standby state is carried out after a predetermined second delay time has elapsed since the washing machine has been placed in the standby state.

In an advantageous embodiment, the plurality of further electrical loads comprises a user interface, wherein the user interface is disconnected from the power supply when the washing machine is in the standby state.

In an advantageous embodiment, once the drain pump has been activated to drain liquid from the washing tub when the washing machine is in the standby state, the drain pump remains activated until the value detected by the liquid level detector, which is indicative of the amount of liquid level inside the washing tub, meets a second predetermined condition and/or for a predetermined activation time.

In a further advantageous embodiment, the drain pump is powered for the entire duration of the standby state when the washing machine is in the standby state.

In a further advantageous embodiment, the drain pump is powered only when the first value satisfies the first predetermined condition when the washing machine is in the standby state.

In a preferred embodiment, when the washing machine is in a standby state, the following three phases are repeated in this order a plurality of times;

-supplying power to the level detector for at least a first on-time interval;

-detecting, by the level detector, a first value indicative of the amount of liquid level inside the washing tub during the first opening time interval;

Preferably, the three phases are repeated a plurality of times at predetermined time intervals when the washing machine is in a standby state.

Preferably, during the repetition of these three phases, the drain pump is activated if the first level meets a first predetermined condition when the washing machine is in a standby state.

In an advantageous embodiment, when the washing machine is in the standby state, the level detector is kept powered for the entire remaining duration of the standby state if the first value detected by the level detector satisfies the first predetermined condition.

In a further advantageous embodiment, the method comprises: the level detector is powered for the entire duration of the standby state.

In a further advantageous embodiment, the washing machine comprises a door or porthole configured to selectively close the washing tub, and a closure detection device operatively connected to the control unit, the closure detection device being configured for detecting whether the door or porthole is open or closed, wherein, if the first value satisfies a first predetermined condition, the method comprises the following steps, while the washing machine is in the standby state and before the step of activating the drain pump to drain liquid from the washing tub and/or generating the alarm:

-detecting by means of a closing detection device whether the door or porthole is closed or open, and using a first predetermined condition if the door or porthole is closed and a different first predetermined condition if the door or porthole is open.

It is emphasized that the first predetermined condition to be used depending on the closed state of the door may advantageously be selected, for example by the electronic control unit, between a plurality of first predetermined conditions (preferably comprised in and/or functionally associated with the control unit) stored in a storage device of the washing machine.

In a further advantageous embodiment, the first predetermined condition to be used depending on the closing state of the door may advantageously be set and/or calculated and/or processed, for example by the electronic control unit, according to data indicative of the closing state of the door, and optionally also other data related to the washing machine.

Advantageously, the value of the predetermined first threshold value when the door or porthole is closed is higher than the value of the first threshold value when the door or porthole is open.

In a further advantageous embodiment, the value of the predetermined second threshold value when the door or the porthole is closed is higher than the value of the second threshold value when the door or the porthole is open.

In a still further advantageous embodiment, the predetermined value of the third threshold value when the door or the porthole is closed is higher than the value of the third threshold value when the door or the porthole is open.

The above object is also solved by a washing machine comprising:

-a washing tub;

-one or more electrovalves through which liquid is admitted into the washing tub;

-a liquid level detector configured for detecting a liquid level inside the washing tub;

-a drain pump configured for draining liquid from the washing tub;

-a plurality of further electrical loads;

-a control unit configured for controlling the liquid level detector, the drain pump and the plurality of further electrical loads, wherein the control unit is configured to control the one or more electrically operated valves, the liquid level detector, the drain pump and the plurality of further electrical loads in a manner to carry out the method according to the invention.

Further advantages and characteristics of the washing machine according to the invention will become clear from the following detailed description, provided purely by way of non-limiting example, in which:

fig. 1 is a perspective view of a washing machine, in particular a laundry washing machine, according to the present invention;

fig. 2 is a schematic front view section of a washing machine, in particular a laundry washing machine, according to the present invention, with some parts not shown;

FIG. 3 is a flow chart illustrating some of the operations of a first embodiment of a method in accordance with the present invention;

FIG. 4 is a flow chart illustrating some of the operations of a second embodiment of a method in accordance with the present invention;

fig. 5 is a flow chart illustrating some operations of further embodiments of methods in accordance with the present invention.

In the drawings, like parts are denoted by like reference numerals.

Advantageously, the washing machine 10 illustrated in the figures is a laundry washing machine, in particular a front-loading laundry washing machine; it is clear, however, that the invention can also be applied, without any substantial modification, to top-loading washing machines of the "horizontal axis" and "vertical axis" type.

Furthermore, the present invention may also be applied to a washing and drying machine (i.e., a washing machine provided with a drying system for drying laundry in addition to being capable of washing laundry) without any substantial modification.

It is clear that the invention can also be applied to a dishwasher (not shown) without any substantial modification.

The washing machine 10 advantageously comprises a cabinet 20 or casing (preferably substantially parallelepiped), advantageously provided with feet 22 configured to be positioned on a horizontal plane 23 (for example the floor of a building).

The cabinet 20 houses a washing tub 30 in which the items to be washed (i.e. the laundry in the case of a washing machine or washer-dryer, or the crockery or cutlery in the case of a dishwasher) can be loaded via an access opening (not shown) closable by a door or porthole 4, preferably hinged to the cabinet 20.

In an advantageous embodiment in which the washing machine 10 is a washing machine or washer-dryer, as in the example illustrated in fig. 1 and 2, the washing tub 30 may be preferably suspended from the cabinet 20 by means of springs and dampers (not illustrated).

In an advantageous embodiment in which the washing machine 10 is a washing machine or a washer-dryer, as in the example illustrated in fig. 1 and 2, the washing tub 30 advantageously comprises a drum 40 rotatable with respect to an axis of rotation (not illustrated), in which the clothes can be loaded.

In so-called "horizontal axis" washing machines, the axis of rotation of the drum 40 is advantageously horizontal or slightly inclined, whereas in so-called "vertical axis" washing machines, the axis is vertical.

In an advantageous embodiment when the washing machine 10 is a washing machine or a washer-dryer, as in the example illustrated in fig. 1 and 2, the washing machine comprises at least one (preferably two or more) lifter 41 (also called lifter, rib or deflector) adapted to improve agitation of the laundry during rotation of the drum 40.

In a further advantageous embodiment (not shown) in which the washing machine is a dishwasher, the washing tub 30 advantageously comprises one or more racks (not shown) in which the items to be washed can be loaded.

The washing machine 10 advantageously comprises a water inlet circuit 60 suitable for supplying water, or water mixed with washing/rinsing additives, into the tub 30; the water inlet circuit 60 advantageously comprises a first pipe 61, a first end of which is preferably connected or connectable to a water delivery mains (not shown) external to the washing machine 10, for example a building water delivery mains (not shown). The second end of the first duct 61 is fluidly connected to one or more electronic valves 70 configured to allow/prevent water from the first duct 61 to flow to the second duct 62, which is fluidly connected to the interior of the washing tub 30.

In an advantageous embodiment in which the washing machine 10 is a washing machine or washer-dryer, as in the example illustrated in fig. 1 and 2, preferably between the one or more electrovalves 70 and the second duct 62 there is an additive drawer 80, which is arranged in such a way that the water coming from the first duct 61 and passing through the one or more electrovalves 70 can be mixed with the additives (for example detergent and/or softener) contained in the additive drawer 80 and then admitted into the washing tub 30 via the second duct 62.

In a further advantageous embodiment (not shown) in which the washing machine 10 is a dishwasher, preferably no such additive drawer 80 is provided, and water from a water delivery mains external to the washing machine 10 is admitted, without mixing with the additive, into the washing tub 30 through the first conduit 61, the one or more electrovalves 80 and the second conduit 62; in this case, preferably, the washing machine 10 comprises an additive dispenser, preferably located inside the door or porthole facing the inside of the washing tub 30, and configured for delivering an additive into the washing tub 30 during the washing cycle, so that such additive is mixed with the water present in the washing tub 30.

Advantageously, the washing tub 30 is fluidly connected to a drain circuit 90 configured for draining liquid from the bottom of the washing tub 30.

Advantageously, the draining circuit 90 comprises one or more pipes 91 and a draining pump 92 configured for drawing liquids from the bottom of the washing tub 30 and draining such liquids to the outside of the washing machine 10.

Preferably, the drain circuit 90 includes a filter 93 fluidly connected upstream of the drain pump 92 for preventing foreign objects from reaching and obstructing/damaging the drain pump.

In an advantageous embodiment (as illustrated in fig. 1 and 2), the washing machine 10 may comprise a non-return valve 94, preferably arranged at the outlet of the washing tub 30 or at the inlet of the discharge circuit 90, for keeping the washing liquid inside the washing tub 30 during part of the washing cycle.

For example, in an advantageous embodiment (such as that illustrated in fig. 1 and 2), the check valve 94 comprises a float 95 (e.g., a hollow plastic ball) that is freely movable or floatable within the drain circuit 90 in engagement with a valve seat 96 and that fluidly separates the wash tub 2 from the drain circuit 90 when the liquid level in the drain circuit 90 rises above a certain value.

The washing machine 10 may advantageously comprise a recirculation circuit (not shown) configured for extracting liquid from the washing tub 30 and re-admitting such liquid into different zones of the washing tub 30, in order to reach more efficiently all the items to be washed loaded into the washing tub.

The washing machine 10 further comprises a liquid level detector 100 configured for detecting a quantity indicative of the liquid level inside the washing tub 30.

It is emphasized that in the present application, the expression "an amount indicative of the liquid level inside the washing tub" refers to an amount having a specific and corresponding relationship with the liquid level inside the washing tub 30; for example, the quantity indicative of the liquid level within the washing tub may be the liquid level itself (e.g. if the liquid level detector is an optical sensor configured to directly sense the liquid level), or a quantity, such as the liquid pressure within the washing tub 30, which has a corresponding relationship (e.g. is directly proportional) to the liquid level within the washing tub 30.

It is emphasized that the liquid level inside the washing tub 30 is advantageously a reference liquid level L set with respect to the liquid level detector 100 _ref Defined and may be a preset reference level or, in a further advantageous embodiment, a level that can be set by a user, for example by operating on the user interface 50 (if provided), as will be better described below.

For example, in an advantageous embodiment (such as the one illustrated in fig. 1 and 2), the reference level L against which the liquid level inside the washing tub 30 is measured _ref May be the level of the valve seat 96 of the check valve 94.

In a further advantageous embodiment (not shown), the reference level L _ref May be, for example, the level of the lowest point of the washing tub 30, or the level of the bottom of the housing 20, or the level of the surface 23 on which the washing machine 10 is configured to be placed; in any case, other reference levels L may be used _ref 。

In a preferred embodiment, the liquid level detector 100 comprises a gas chamber 101 having a liquid inlet provided at the washing tub 30 and in fluid communication with the inside of the washing tub; the plenum 101 is preferably fluidly connected, more preferably by a third conduit 102, to a sensing element 103 of the liquid level detector 100.

Advantageously, the sensing element 103 may be a pressure sensor; advantageously, the sensing element 103 may comprise an electronic unit (not illustrated) configured for calculating/determining the liquid level inside the washing tub 30 as a function of the detected pressure; alternatively or in addition, the electronic unit of the sensing element 103 may be connected to the control unit 200 of the washing machine 30, as will be better described hereinafter.

In an advantageous embodiment, when the washing liquid/rinsing liquid contained in washing tub 30 reaches a certain level of its entry into air chamber 101 during the washing cycle, such washing liquid/rinsing liquid compresses the air contained in air chamber 101, so that the pressure is transmitted through third duct 102 to sensing element 103 (e.g. a pressure sensor) configured for detecting the pressure in air chamber 101.

The pressure detected by the sensing element 103 is then used directly by the sensing element 103 (for example, if provided with an integrated electronic unit) or by an external electronic unit (for example, the control unit 200 of the washing machine 10) connected to the sensing element 103 (for calculating the liquid level inside the washing tub 30), as will be better described hereinafter.

Advantageously, as mentioned above, the washing machine 10 may comprise a user interface 50, advantageously comprising one or more electric or electronic input/output devices, such as a display 51 (for example a so-called "touch screen" display), one or more knobs 52, one or more switches 53, one or more loudspeakers (not shown) or the like.

As mentioned above, the washing machine 10 advantageously comprises a control unit 200, for example an electronic board provided with a microcontroller (schematically illustrated as a rectangle in fig. 2), configured for controlling one or more electronic valves 70, the level detector 100, the drain pump 92, and a plurality of further electrical loads of the washing machine 10.

Such a plurality of further electrical loads may comprise, for example, the user interface 50, and/or an electrical heater (not shown) for heating the washing liquid, and/or an electric motor (not shown), and/or a loudspeaker (not shown), and/or one or more further sensors (e.g. a turbidity sensor, a temperature sensor, etc.) (not shown).

In a preferred embodiment, the control unit 200 may advantageously be configured/programmed in a manner to control the one or more electrovalves 70 as a function of the washing cycle and/or the value indicative of the amount of liquid level inside the washing tub 30 detected by the liquid level detector 100.

The method according to the invention comprises the following steps: placing the washer 10 in a standby state in which the one or more electrically operated valves 70, and one or more of the plurality of additional electrical loads, are disconnected from the electrical power source.

It is emphasized that in the present application, in the case of power supply with alternating current, the moment when the alternating current is periodically reversed (i.e. its value is zero) is not considered as a power interruption; in the case of alternating current, the power source is considered to be disconnected if it is not powered for at least the entire cycle of the periodic power.

For example, in the standby state, the electrical load that may be disconnected from the power supply may be the user interface 50 (if provided), and/or the electrical heater (if provided), and/or the temperature sensor (if provided), and/or the electric motor (if provided), and/or the like.

By disconnecting the power supply, it is ensured that such electrical loads do not absorb electrical energy when not in operation, thereby reducing the overall energy consumption of the washing machine 10.

Advantageously, the control unit 200 may be configured for automatically placing the washing machine 10 in a standby state at the end of the washing cycle and/or after receiving a specific command of the user, for example through the user interface 50 (if provided).

The method according to the invention comprises the following steps: when the washing machine 10 is in a standby state, power is supplied to the liquid level detector 100 for at least a first on-time interval t _ON1 。

First on time interval t _ON1 Preferably between 5 seconds and 15 seconds, more preferably 10 seconds.

According to the method of the invention, during such a first on-time interval t _ON1 Meanwhile, the liquid level detector 100 detects a first value L1 indicating the amount of the liquid level inside the washing tub 30.

Then, according to the present invention, if the first value L1 satisfies the first predetermined condition, the drain pump 92 is activated to drain the liquid from the washing tub 30 and/or to generate an alarm (e.g., sound).

In the first advantageous embodiment, the drain pump 92 is powered (and therefore can be activated to drain liquid from the washing tub 30) for the entire duration of the standby state.

In a different advantageous embodiment, in the standby state, the drain pump 92 is powered (so that it can be activated to drain liquid from the washing tub 30) only when the first value L1 satisfies the first predetermined condition.

In a further advantageous embodiment, when washing machine 10 is in the standby state, once drain pump 92 has been activated to drain liquid from washing tub 30, the drain pump remains activated until the amount indicative of the liquid level inside washing tub 30 detected by liquid level detector 100 satisfies a second predetermined condition (for example, if the value indicative of the amount of the liquid level inside washing tub 30 detected by liquid level detector 100 is lower than a predetermined value L _OFF ) And/or for a predetermined activation time t _act (e.g., in the range between 1 and 2 minutes).

In a first advantageous embodiment, the first predetermined condition on the first value L1 is or includes reaching or exceeding a predetermined first threshold value L _thr1 (ii) a Thus, in this first advantageous embodiment, if during the standby state, i.e. when one or more electronic valves 70 are not operating, the liquid level inside washing tub 30 increases beyond a predetermined threshold (this increase corresponding to the value of the increase in detected value L1), which may mean that one or more electronic valves 70 are leaking, drain pump 92 is activated to drain liquid from washing tub 30 so as to avoid further raising, and/or to generate an alarm, for example by sounding a speaker (not shown) provided in washing machine 10 to inform the user of this leakage.

It is emphasized that the predetermined first threshold value L may be selected according to the specific size and/or shape of the washing tub 30 and/or the discharge circuit 90, for example during the design of the washing machine 10 _thr1 In such a case, when the first value L1 is lower than the first threshold value L _thr1 At this time, the liquid cannot overflow from the washing tub 30.

Preferably, the first threshold value L is a first threshold value L if the quantity indicative of the liquid level inside the washing tub is the liquid level itself _thr1 May be between 70 and 140 mm.

In this first advantageous embodiment (wherein the first predetermined condition with respect to the first value L1 is or includes reaching or exceeding a predetermined first threshold value L _thr1 ) If, once activated, the drain pump 92 remains activated until the quantity detected by the level detector 100, which indicates the level of liquid in the washing tub 30, is lower than a predetermined value L _OFF The predetermined value L _OFF May be related to a predetermined first threshold value L _thr1 The same, or preferably, the predetermined value may be a different value, more preferably lower than the predetermined first threshold value L _thr1 To introduce hysteresis when the drain pump 92 is activated/deactivated.

Further possible advantageous first predetermined conditions for the first value L1 according to the invention will be described below.

In an advantageous embodiment, when the washing machine 10 is in standby stateAnd is powered to the liquid level detector 100 for at least a first on-time interval t _ON1 After stage (b), the method comprises: disconnecting the liquid level detector from the power supply for a first off-time interval t _OFF1 (ii) a In this way, the total energy consumption during the standby state is reduced.

In a preferred embodiment, the first switch-off time interval t _OFF1 Between 50 seconds and 70 seconds, more preferably 60 seconds.

In a further advantageous embodiment, when the washing machine 10 is in the standby state, if the first value L1 detected by the level detector 100 satisfies the first predetermined condition, the level detector 100 is kept powered for the entire remaining duration of the standby state.

In an advantageous embodiment, the method comprises: detecting or estimating a starting value L0 indicating the amount of liquid level inside the washing tub 30 at the start of the standby state; the starting value L0 may for example be the last value of the quantity indicative of the liquid level detected before putting the washing machine 10 in a standby state. In another advantageous embodiment, the starting value L0 may, for example, be estimated as a value indicative of the amount of level of liquid that may remain inside the washing tub 30 after the last discharge phase of the washing cycle, for example due to the specific layout of the discharge circuit 90. In this advantageous embodiment, the first value L1 is compared with a starting value L0 and if the difference between the first value L1 and the starting value L0 reaches or exceeds a predetermined second threshold value L _thr2 Then the drain pump 92 is activated; in this case, therefore, the first predetermined condition that the first value L1 must satisfy is related to its difference from the starting value L0; it is clear that this difference increases with the amount of leakage of the one or more electrovalves 70.

It is emphasized that the predetermined second threshold value L may be selected according to the specific size and/or shape of the washing tub 30 and/or the discharge circuit 90, for example during the design of the washing machine 10 _thr2 In such a case, when the difference between the first value L1 and the starting value L0 is lower than the second threshold value L _thr2 At this time, the liquid cannot overflow from the washing tub 30.

For example, if the quantity indicative of the level of liquid inside the washing tub is the level itself, the second threshold value L _thr2 Can be connected withBetween 70 and 140 mm.

In a further advantageous embodiment of the invention, the method is carried out while the washing machine 10 is in standby state and while the level detector 100 is powered for at least a first switching-on time interval t _ON1 Includes supplying power to the liquid level detector 100 for a second on-time interval t _ON2 During which the level detector 100 detects a second value L2 indicative of the quantity of liquid level inside the washing tub 30. In this advantageous embodiment, the second value L2 is compared with the first value L1 and if the difference between the second value L2 and the first value L1 reaches or exceeds a predetermined third threshold value L _thr3 The drain pump 92 is activated to drain liquid from the washing tub 30 and/or to generate an alarm, for example, through a speaker (not shown). In this case, therefore, the first predetermined condition that the first value L1 must satisfy is related to the difference between the second value L2 and the first value L1; it is clear that this difference increases with the amount of leakage of the one or more electrovalves 70.

It is emphasized that the predetermined third threshold value L may be selected according to the specific size and/or shape of the washing tub 30 and/or the discharge circuit 90, for example during the design of the washing machine 10 _thr3 In such a case, when the difference between the second value L2 and the first value L1 is lower than the third threshold value L _thr3 At this time, the liquid cannot overflow from the washing tub 30.

For example, if the quantity indicative of the liquid level inside the washing tub is the liquid level itself, the third threshold value L _thr3 May be between 50 and 100 mm.

In this advantageous embodiment, the liquid level detector is disconnected from the power supply for a first off-time interval t _OFF1 Is preferably powered for a first on-time interval t to the liquid level detector 100 _ON1 And supplying power to the liquid level detector 100 for a second on-time interval t _ON2 Between stages of (a). Alternatively, in a further advantageous embodiment, the supply of power to the liquid level detector 100 is carried out for a first on-time interval t _ON1 And supplying power to the liquid level detector 100 for a second on-time interval t _ON2 Without disconnecting the liquid level detector 100 from power supply between stagesOn (i.e., the liquid level detector 100 is at least turned on for a time interval t from the first on _ON1 Starting to a second on-time interval t _ON2 Ending being continuously powered).

Preferably, when the washing machine 10 is in a standby state and when the level detector 100 is powered for a second on-time interval t _ON2 After the stage (b), the method comprises the following stages: disconnecting the liquid level detector 100 from the power supply for a first off-time interval t _OFF2 To reduce power consumption. Preferably, the second off time interval t _OFF2 Between 50 and 70 seconds, more preferably 60 seconds.

In a preferred embodiment, when the washing machine 10 is in a standby state, power is supplied to the level detector 100 for at least a first on-time interval t _ON1 Is at the end of a predetermined first delay time t after the washing machine 10 has been put into a standby state _d1 Thereafter, during the predetermined first delay time, the liquid level detector 100 is disconnected from the power source; in other words, in this advantageous embodiment, when the washing machine 10 is placed in the standby state, the level detector 100 is disconnected from the power supply and then connected to the power supply, so as to be only for the first delay time t _d1 And is then powered.

Preferably, the first delay time t _d1 Between 30 seconds and 90 seconds, more preferably between 50 seconds and 70 seconds, even more preferably 60 seconds.

In a preferred embodiment, the liquid level detector 100 is powered for at least a second on-time interval t _ON2 Is at a stage when a predetermined second delay time t has elapsed since the washing machine 10 has been put into a standby state _d2 And then the process is carried out. Preferably, the second on-time interval t _ON2 Between 30 seconds and 90 seconds, more preferably between 55 seconds and 85 seconds, even more preferably 70 seconds.

In a further advantageous embodiment, the level detector is supplied with power for at least a first opening time interval t _ON1 Is started simultaneously with placing the washing machine 10 in a standby state.

In a further advantageous embodiment, the liquid level detector 100 is powered for the entire duration of the standby state.

Preferably, during the standby state, the user interface 50 is disconnected from the power supply.

Preferably, when the washing machine 10 is in the standby state, the following three phases are repeated in this order a plurality of times:

supplying power to the liquid level detector 100 for at least a first on-time interval t _ON1 ；

-during the first on-time interval t _ON1 Meanwhile, a first value L1 indicating the amount of the liquid level inside the washing tub 30 is detected by the liquid level detector 100;

disconnecting the liquid level detector 100 from the power supply for a first off time interval t _OFF1 。

Preferably, the three phases are repeated a plurality of times at predetermined time intervals.

Preferably, in this advantageous embodiment, if during the repetition of these three phases the first value L1 satisfies a first predetermined condition, for example it reaches or exceeds a predetermined first threshold value L _thr1 The drain pump 92 is activated.

In a further advantageous embodiment, the washing machine 10 comprises a closing detection device (schematically illustrated as a rectangle 44 in fig. 2), for example a sensor (for example a magnetic sensor), operatively connected to the control unit 200 and configured for detecting whether the door or porthole 4 is open or closed. In this advantageous embodiment, when the washing machine 10 is in the standby state and before the step of activating the drain pump 92 to drain liquid from the washing tub 30 and/or to generate an alarm, the method according to the present invention may advantageously comprise the following further steps: if the first value L1 satisfies a first predetermined condition, the closure detection means 44 detects whether the door or porthole 4 is closed or open and utilizes the first predetermined condition if the door or porthole 4 is closed and utilizes a different first predetermined condition if the door or porthole 4 is closed.

For example, if the first predetermined condition comprises reaching or exceeding a predetermined first threshold L _thr1 Then the predetermined first threshold value L _thr1 May advantageously have a value of, for example, 200mm (in indicating the washing tub) when the door or porthole 4 is closedIs the liquid level itself) and has a different value, for example 140mm, when the door or porthole 4 is open; in fact, if the door or porthole 4 is closed, liquid cannot escape via the opening closed by the door or porthole 4, and therefore a predetermined first threshold L can be used _thr1 The higher value of (a).

In the first predetermined condition, the difference between the first value L1 and the starting value L0 is related to and in particular the difference between the first value L1 and the starting value L0 is required to reach or exceed a predetermined second threshold value L _thr2 In a further advantageous embodiment of the invention, the predetermined second threshold value L _thr2 It may be advantageous to have a value of, for example, 200mm when the door or porthole 4 is closed (in the case where the amount indicating the displacement in the washing tub is the liquid level itself), and a different value of, for example, 140mm when the door or porthole 4 is open; in fact, if the door or porthole 4 is closed, liquid cannot escape via the opening closed by the door or porthole 4, and therefore a predetermined second threshold L can be used _thr2 The higher value of (a).

In the first predetermined condition, the difference between the second value L2 and the first value L1 and, in particular, the difference between the second value L2 and the first value L1 is required to reach or exceed a predetermined third threshold value L _thr3 In a further advantageous embodiment of the invention, the predetermined third threshold value L _thr3 It may be advantageous to have a value of, for example, 160mm when the door or porthole 4 is closed (in the case where the quantity indicating the displacement inside the washing tub is the liquid level itself), and a different value of, for example, 100mm when the door or porthole 4 is open; in fact, if the door or porthole 4 is closed, the liquid cannot escape through the opening closed by the door or porthole 4, so the third threshold L is predetermined _thr3 May have a higher level.

An advantageous example of a first flowchart 1000 illustrating an advantageous embodiment of logical steps performed by the control unit 200 for implementing a possible embodiment of the method according to the present invention is illustrated in fig. 3.

The first flowchart 1000 starts from a first step 1001, i.e. checking (advantageously by the control unit 200) whether the washing machine 10 is in a standby state; if "no" (indicated by the letter "N" in the figure), the first step 1001 is repeated, if "yes" (indicated by the letter "Y" in the figure), a second step 1002 is performed, i.e. the level of water inside the washing tub 30 is supplied with power and detected by the level detector 100 (or better the first value L1 indicating the amount of the level of water), and then the level detector 100 is switched off (called the pressure switch in fig. 3) (third step 1003).

Then, a fourth step 1004 of checking whether the first off-time interval t of the liquid level detector 100 has been reached is performed _OFF1 (referred to as "off time" in FIG. 3); if "no", the fourth step 1004 is repeated, and if yes, the liquid level detector 100 is powered again (fifth step 1005) for a second on-time interval t _ON2 (sixth step 1006, "on time"), then the water level inside the washing tub 30 (or better the second value L2 of the quantity indicative of the liquid level) is checked again (seventh step 1007).

If (eighth step 1008, option no) the liquid level does not increase beyond a certain threshold (or in other words if the difference between L2 and L1 is below the third threshold), the flow chart returns to third step 1003, whereas if (eighth step 1008, option yes) the liquid level increases beyond a certain threshold (or in other words if the difference between L2 and L1 reaches or exceeds the third threshold L) _thr3 ) An alarm is generated (called warning in fig. 3) and drain pump 92 is operated to drain water from washing tub 30 (ninth step 1009), after which (tenth step 1010) the alarm is transmitted to user interface 50, or APP of an external device (not shown) connected to washing machine 10, and the draining continues until washing tub 30 is completely emptied.

A further advantageous example of logic steps performed by the control unit 200 for implementing a possible embodiment of the method according to the invention is shown in the second flowchart 2000 of fig. 4.

The second flowchart 2000 starts with a first step 2001 of checking whether the washing machine 10 is in a standby state; if "no", the first step 2001 is repeated, and if "yes", the second step 2002 is performed, i.e. the power is supplied to the level detector 100 and the water level inside the washing tub 30 is detected (or better the first value L1 indicating the amount of the liquid level).

Then, a third step 2003 is performed, i.e. it is checked whether a certain time has elapsed; if "no", the third step 2003 is repeated, and if "yes", the water level inside the washing tub 30 (or better the second value L2 of the quantity indicative of the liquid level) is checked again (fourth step 2004).

If (fifth step 2005, option no) the liquid level does not increase beyond a certain threshold (or in other words if the difference between L2 and L1 is below the third threshold), the second flowchart 2000 returns to third step 2003, whereas if (fifth step 2005, option yes) the liquid level increases beyond a certain threshold (or in other words if the difference between L2 and L1 reaches or exceeds the third threshold L) _thr3 ) An alarm is generated (called warning in fig. 4) and drain pump 92 is operated to drain water from washing tub 30 (sixth step 2006), after which (seventh step 2007) the alarm is transmitted to user interface 50, or APP of an external device (not shown) connected to washing machine 10, and the draining continues until washing tub 30 is completely drained.

Fig. 5 shows an advantageous example of an alternative logic step 3000, which may be carried out in the first flowchart 1000 or in the second flowchart 2000 as an alternative to

steps

1001 and 2001, respectively, in an advantageous embodiment in which the washing machine 10 comprises a closure detection device 44 operatively connected to the control unit 200 and configured for detecting whether the door or porthole 4 is open or closed.

This alternative logic step 3000 advantageously comprises:

a first step 3001 of checking whether the washing machine 10 is in a standby state; if "no", the first step 3001 is repeated, if "yes", a second step 3011 is performed, i.e. it is checked by the closing detection device 44 whether the door or porthole 4 is closed.

If "no" (i.e. door or porthole 4 open), then a low threshold level (e.g. L) is selected and used _thr1 、L _thr2 Or L _th3 ) (step 3012), and if yes (i.e., door or porthole 4 is closed) then a high threshold level (e.g., L) is selected and used _thr1 、L _thr2 Or L _th3 ) (step 3013) because in this case, the liquid cannot pass through the passive door or porthole4, the closed opening overflows, thus resulting in a higher level of overflow.

The flowchart may then continue with

step

1002 or 2002, respectively, depending on whether it is the first flowchart 1000 or the second flowchart 2000.

It can thus be seen how the invention achieves the proposed objects and aims, a method for operating a washing machine (for example a washing machine or a dishwasher) is provided, comprising: activating the liquid level detector when the washing machine is in a standby state; and if the liquid level rises abnormally, activating a drain pump and/or generating an alarm, thereby preventing the risk of liquid overflow even in a standby state.

Furthermore, only after a predetermined first delay time t has elapsed since the washing machine has been placed in a standby state _d1 The particular embodiment in which the level detector is only powered afterwards allows to maintain a reduced energy consumption when the washing machine is in a standby state.

Claims

1. A method for operating a washing machine (10), the washing machine comprising: a washing tub (30); one or more electrovalves (70) through which liquid is admitted into said washing tub (30); a liquid level detector (100) configured for detecting an amount indicative of a liquid level within the washing tub (30); a drain pump (92) configured for draining liquid from the washing tub (30); a plurality of further electrical loads (50, 51, 52, 53); a control unit (200) configured for controlling the one or more electronic valves (70), the liquid level detector (100), the drain pump (92), and the plurality of further electrical loads (50, 51, 52, 53), wherein the method comprises: placing the washing machine (10) in a standby state in which the one or more electronic valves (70) and one or more of the plurality of further electrical loads (50, 51, 52, 53) are disconnected from the power supply,

it is characterized in that the preparation method is characterized in that,

the method comprises the following steps:

-when the washing machine (10) is in the standby state, supplying the liquidThe bit detector (100) is powered for at least a first on-time interval (t) _ON1 )；

-during said first on-time interval (t) _ON1 ) During which a first value (L1) indicative of the amount of liquid level inside the washing tub (30) is detected by the liquid level detector (100);

-activating said drain pump (92) to drain liquid from said washing tub (30) and/or generating an alarm if said first value (L1) satisfies a first predetermined condition.

2. The method according to claim 1, wherein the first predetermined condition on the first value (L1) comprises reaching or exceeding a predetermined first threshold value (L;) _thr1 )。

3. Method according to one or more of the preceding claims, wherein said first opening time interval (t) is a time interval (t;) of the preceding claims _ON1 ) Between 5 seconds and 15 seconds.

4. Method according to claim 3, wherein said first on-time interval (t;) _ON1 ) It was 10 seconds.

5. Method according to one or more of the preceding claims, comprising powering said level detector (100) for at least a first on-time interval (t) when said washing machine (10) is in said standby state and when power is supplied to said level detector (10) _ON1 ) After said phase of (a), the following phases are carried out:

-disconnecting the liquid level detector (100) from a power supply for a first off-time interval (t) _OFF1 )。

6. Method according to claim 5, wherein said first switch-off time interval (t) _OFF1 ) Between 50 seconds and 70 seconds.

7. Method according to claim 6, wherein said first off time interval (t) is _OFF1 ) It is 60 seconds.

8. The method according to one or more of the preceding claims, comprising

-detecting or estimating a starting value (L0) indicative of the quantity of liquid level inside the washing tub (30) at the start of the standby state;

-comparing the first value (L1) with the starting value (L0);

-if the difference between the first value (L1) and the starting value (L0) reaches or exceeds a predetermined second threshold value (L;) _thr2 ) The drain pump (92) is activated.

9. Method according to one or more of the preceding claims, comprising powering said level detector (100) for at least a first on-time interval (t) when said washing machine (10) is in said standby state and when power is supplied to said level detector (10) _ON1 ) After said phase of (a), the following phases are carried out:

-powering said level detector (100) for a second on-time interval (t) when said washing machine (10) is in said standby state _ON2 )；

-during said second on-time interval (t) _ON2 ) During which a second value (L2) indicative of the amount of liquid level inside the washing tub (30) is detected by the liquid level detector (100);

-comparing said second value (L2) with said first value (L1);

-if the difference between said second value (L2) and said first value (L1) reaches or exceeds a predetermined third threshold value (L;) _thr3 ) Activating the drain pump (92) and/or generating an alarm.

10. Method according to claim 9 when depending on one or more of claims 5 to 7, wherein the level detector is disconnected from the power supply for a first off time interval (t |) _OFF1 ) Is supplying power to the liquid level detector (100) for a first on-time interval (t) _ON1 ) And supplying power to the liquid level detector (100) for a second on-time interval (t) _ON2 ) Between said stages.

11. Method according to claim 9 or 10, comprising powering said level detector (100) for a second on-time interval (t) when said washing machine (10) is in said standby state and at power supply to said level detector _ON2 ) After said phase of (a), the following phases are carried out:

-disconnecting the liquid level detector from the power supply for a second off-time interval (t) _OFF2 )。

12. Method according to claim 11, wherein said second switch-off time interval (t) _OFF2 ) Between 50 seconds and 70 seconds.

13. Method according to claim 12, wherein said second switch-off time interval (t) _OFF2 ) It was 60 seconds.

14. Method according to one or more of the preceding claims, wherein said level detector (100) is powered for at least a first on-time interval (t) when said washing machine (10) is in said standby state _ON1 ) Is after a predetermined first delay time (t) has elapsed since the washing machine (10) has been put into the standby state _d1 ) Thereafter, the liquid level detector (100) is disconnected from the power source during the predetermined first delay time.

15. The method according to claim 14, wherein the first delay time (t) _d1 ) Between 30 seconds and 90 seconds.

16. The method according to claim 15, wherein the first delay time (t) _d1 ) It is 60 seconds.

17. Method according to one or more of claims 1 to 13, wherein the liquid level detector (100) is powered for at least a first on-time interval (t |) _ON1 ) Is associated with placing said washing machine (10) in saidThe standby state is started simultaneously.

18. Method according to claim 9 or when dependent on claim 9, wherein, when the washing machine (10) is in the standby state, the level detector (100) is powered for at least a second on-time interval (t £ t) _ON2 ) Is after a predetermined second delay time (t) has elapsed since the washing machine has been placed in the standby state _d2 ) And then the process is carried out.

19. A method according to one or more of the preceding claims, wherein said plurality of further electrical loads (50, 51, 52, 53) comprises a user interface (50), wherein said user interface (50) is disconnected from a power supply when said washing machine (10) is in said standby state.

20. Method according to one or more of the preceding claims, wherein, when said washing machine (10) is in said standby condition, once said draining pump (92) has been activated to drain liquid from said washing tub (30), said draining pump (92) remains activated until the value detected by said level detector (100) indicating the amount of liquid level inside said washing tub (30) satisfies a second predetermined condition and/or lasts for a predetermined activation time (t ™) _act )。

21. A method as claimed in one or more of the preceding claims, wherein, when the washing machine (10) is in the standby state, the discharge pump (92) is powered for the entire duration of the standby state.

22. A method as claimed in one or more of claims 1 to 20, wherein, when said washing machine (10) is in said standby state, said discharge pump (92) is powered only when said first value (L1) satisfies said first predetermined condition.

23. Method according to claim 5 or when dependent on claim 5, wherein, when the washing machine (10) is in the standby state, the following three phases are repeated a plurality of times in this order;

-supplying power to the liquid level detector (100) for at least a first on-time interval (t |) _ON1 )；

-disconnecting the liquid level detector from the power supply for a first off time interval (t) _OFF1 )。

24. Method according to claim 23, wherein said three phases are repeated a plurality of times at predetermined time intervals when said washing machine (10) is in said standby state.

25. Method according to claim 23 or 24, wherein, when said washing machine (10) is in said standby condition, during the repetition of said three phases, said drain pump (92) is activated if said first level (L1) satisfies said first predetermined condition.

26. Method according to claim 1, wherein, when said washing machine (10) is in said standby state, if said first value (L1) detected by said level detector (100) satisfies said first predetermined condition, said level detector (100) is kept powered for the entire remaining duration of said standby state.

27. The method of claim 1, comprising: -powering the liquid level detector (100) for the whole duration of the standby state.

28. Method according to one or more of the preceding claims, wherein said washing machine (10) comprises a door or porthole (4) configured to selectively close said washing tub (30), and closing detection means (44) operatively connected to said control unit (200), said closing detection means being configured for detecting whether said door or porthole (4) is open or closed, wherein, if said first value (L1) satisfies a first predetermined condition, said method comprises, when said washing machine (10) is in said standby state and before said step of activating said draining pump (92) to drain liquid from said washing tub (30) and/or generate an alarm, the steps of:

-detecting by means of said closing detection means (44) whether said door or porthole (4) is closed or open, and using a first predetermined condition if said door or porthole (4) is closed and a different first predetermined condition if said door or porthole (4) is open.

29. Method according to claim 28 when depending on claim 2 or on claim 2, wherein said predetermined first threshold value (L) is determined when said door or porthole (4) is closed _thr1 ) Above the first threshold value when the door or porthole (4) is open.

30. Method according to claim 28 when dependent on claim 8 or on claim 8, wherein said predetermined second threshold value (L) is said when said door or porthole (4) is closed _thr2 ) Above the second threshold value when the door or porthole (4) is open.

31. Method according to claim 28 when depending on claim 9 or when depending on claim 9, wherein said predetermined third threshold value (L) is said when said door or porthole (4) is closed _thr3 ) Above the third threshold value when the door or porthole (4) is open.

32. A washing machine (10) comprising:

-a washing tub (30);

-one or more electrovalves (70) through which liquid is admitted into said washing tub (30);

-a liquid level detector (100) configured for detecting a liquid level within the washing tub (30);

-a drain pump (92) configured for draining liquid from the washing tub (30);

a plurality of further electrical loads (50, 51, 52, 53),

-a control unit (200) configured for controlling the liquid level detector (100), the drain pump (92), and the plurality of further electrical loads (50, 51, 52, 53),

it is characterized in that the preparation method is characterized in that,

the control unit (200) is configured for controlling the one or more electronic valves (70), the liquid level detector (100), the drain pump (92), and the plurality of further electrical loads (50, 51, 52, 53) in a manner to implement the method according to one or more of the preceding claims.