CN114980790A

CN114980790A - Washing appliance, method for detecting operation error, and control device

Info

Publication number: CN114980790A
Application number: CN202080093903.2A
Authority: CN
Inventors: D·佩尔松
Original assignee: Electrolux Appliances AB
Current assignee: Electrolux Appliances AB
Priority date: 2020-01-24
Filing date: 2020-01-24
Publication date: 2022-08-30
Also published as: AU2020424948A1; EP4093257A1; US20230062451A1; WO2021148132A1

Abstract

A washing appliance (1) is disclosed, comprising a liquid container (3), a level indicator unit (5, 7) configured to provide data indicative of a liquid level (8) in the liquid container (3), a drain conduit (15), and a drain pump (13). The washing appliance (1) further comprises a control device (9) configured to operate the drain pump (13) for a first period of time, to control the drain pump (13) to stop for a second period of time after the first period of time, and to monitor a change in the liquid level (8) during the second period of time using data from the level indicator unit (5, 7). The disclosure further relates to a method (100) of detecting an operational error in a washing appliance (1), a computer program, a computer readable medium (200), and a control device (9) for a washing appliance (1).

Description

Washing appliance, method for detecting operation error, and control device

Technical Field

The present disclosure relates to a washing appliance comprising a drain conduit and a drain pump configured to drain a liquid container via the drain conduit. The disclosure further relates to a method of detecting an operational error in a washing appliance, a computer program, a computer readable medium, and a control device for a washing appliance.

Background

A washing appliance is a device capable of washing items. These washing appliances have been developed as a way to reduce the cost of manual labor. Washing appliances include dishwashers and washing machines. Dishwashers are devices used for washing items such as dishes and cutlery. Dishwashers include washing chambers in which articles are generally positioned in racks, and dishwashers typically include one or more spray arms that spray wash liquid (e.g., a mixture of water and detergent) onto the articles to clean them. The washing liquid is collected in a sump at the bottom of the washing chamber. A circulation pump of the dishwasher is fluidly connected to the sump and pumps wash liquor from the sump to the spray arms during a wash cycle. In order to increase the cleaning efficiency and improve the final cleaning result, the washing liquid is heated to a higher temperature, typically between 45 ℃ and 75 ℃, by one or more heating elements of the dishwasher.

A washing machine is an apparatus for washing articles such as laundry. Washing machines are sometimes referred to as laundry machines, laundry washing machines, or simply washing machines. In most cases, washing machines comprise a perforated washing drum arranged in a drum compartment of the washing machine. The drum compartment includes a sump at its bottom. During operation, the drum compartment is filled with washing liquid (e.g. a mixture of water and detergent) and the washing drum is driven to rotate in the drum compartment. In this way, the articles in the drum are cleaned due to the movement of the articles within the washing drum. In order to increase the washing efficiency and improve the final washing result, the washing liquid is heated to a higher temperature, typically between 30 ℃ and 90 ℃, by one or more heating elements of the washing machine.

In most cases, the washing appliance includes a drain conduit and a drain pump configured to drain the sump via the drain conduit. The drain conduit of the washing appliance is typically installed and connected to the drain by a user or installer prior to the first use of the washing appliance. The sump may be drained, for example, at the end of the washing program and/or between wash cycles of the washing program via a drain conduit. Further, the washing appliance comprises a control device configured to control the operation of the washing appliance. The control means may for example control the operation of a circulation pump, a drain pump, one or more heating elements, one or more valves, a motor for rotating the washing drum, etc. The operation of a washing appliance is associated with several operational aspects. Examples are temperature, intensity of operation, duration of operation, loading of articles, amount of washing liquid etc.

A problem associated with washing appliances is that operational errors may occur in the operation of the washing appliance. A wrongly installed discharge conduit may for example cause operational errors. Operational errors can lead to several false decisions in the control logic of the washing appliance and have potential subsequent problems such as overheating, increased risk of fire, damaged components, flooding, etc.

Operational errors can be difficult to detect, but their incidence can be reduced by providing advanced control systems and devices for the washing appliance. However, such systems and devices generally add to the cost and complexity of the washing appliance, and it is generally advantageous in today's consumer market that products, such as washing appliances, have conditions and/or characteristics suitable for manufacturing and assembly in a cost-effective manner.

Disclosure of Invention

It is an object of the present invention to overcome or at least alleviate at least some of the above problems and disadvantages.

According to a first aspect of the invention, this object is achieved by a washing appliance comprising: a liquid container configured to contain a liquid; a liquid level indicator unit configured to provide data indicative of a liquid level in a liquid container; a discharge conduit; and a drain pump configured to drain the liquid container via the drain conduit. The washing appliance further comprises a control device configured to operate the drain pump for a first period of time, to control the drain pump to stop for a second period of time after the first period of time, and to monitor changes in the liquid level during the second period of time using data from the level indicator unit.

As mentioned above, the drain conduit of the washing appliance is typically installed and connected to the drain by the user or installer prior to the first use of the washing appliance. When the discharge conduit is filled with liquid, a siphon effect may occur in the discharge conduit, causing liquid to be sucked out of the liquid container in an unintended manner, even when the discharge pump is not operating. The siphon effect in the discharge conduit may be due to the fact that: the discharge conduit is mounted at a too low height and/or if the connection of the discharge conduit to the discharge port is sealed without any free path between the discharge conduit and the ambient air to achieve pressure equalization.

In some cases, the siphon effect in the drain conduit may be due to the fact that the drain conduit becomes loose from the drain connection. If so, a large amount of liquid may be drained inside/under cabinets and floors/walls. Furthermore, the siphon effect in the drain conduit may lead to several false decisions in the control logic of the washing appliance and have potential subsequent problems, such as overheating, increased risk of fire, damage to components, flooding, etc.

Since the control device of the washing appliance according to the present disclosure is configured to monitor the change of the liquid level during the second period of time, a washing appliance is provided which is capable of detecting the presence of a siphon effect in the drain conduit in a simple and efficient manner. Furthermore, a washing appliance is provided which is capable of detecting whether liquid leaves the liquid container for some other reason, for example due to leakage.

Furthermore, a washing appliance is provided which is capable of detecting whether liquid leaves the liquid container in an unintended manner, while having conditions and characteristics suitable for being manufactured and assembled in a cost-effective manner. This is because such operational errors can be detected using a simple and low-cost level indicator unit.

As a further result thereof, conditions are provided for improving the operational safety of the washing appliance, for example by performing one or more appropriate actions if a monitored change in the liquid level deviates from an expected change in the liquid level.

In this way, the operational safety of the washing appliance can be increased and incorrect decisions in the control logic of the washing appliance can be avoided, so that also potential subsequent problems, such as overheating, fire risks, component damage, flooding, etc., are avoided.

Accordingly, a washing appliance is provided to overcome or at least alleviate at least some of the above problems and disadvantages. Thus, the above object is achieved.

Optionally, the liquid is a wash liquid used in a washing process of the washing appliance. Thus, a washing appliance is provided which is capable of detecting whether washing liquid leaves the liquid container in an unintended manner in a simple and cost-effective manner.

Optionally, at least a portion of the discharge conduit is routed through a point above the liquid container. Thus, a washing appliance is provided which is capable of detecting a siphon effect in the drain conduit in a simple and cost-effective manner.

Optionally, the control means is configured to monitor changes in the liquid level in order to detect the presence of a siphon effect in the discharge conduit. Thus, a washing appliance is provided which is capable of detecting a siphon effect in a drain conduit in a simple and cost effective manner. As a further result, the operational safety of the washing appliance can be improved and erroneous decisions in the control logic of the washing appliance can be avoided, thus also avoiding potential subsequent problems, such as overheating, fire risk, component damage, flooding, etc.

Optionally, the washing appliance comprises a circulation pump, and wherein the control device is configured to monitor the change in the liquid level and to monitor one or more electrical quantities of the circulation pump by operating the circulation pump. Thus, a washing appliance is provided in which a circulation pump is used as a level indicator unit. In this way, the need for a separate sensor or device to sense the liquid level in the liquid container is avoided. Thus, thanks to these features, a washing appliance is provided having conditions and characteristics suitable for being manufactured and assembled in a cost-effective manner.

Optionally, the control device is configured to monitor the change in the liquid level by detecting the liquid level at two or more points in time and comparing the liquid levels detected at the respective two or more points in time. Thus, a simple and effective monitoring of the change of the liquid level is provided. Thus, thanks to these features, a washing appliance is provided having conditions and characteristics suitable for being manufactured and assembled in a cost-effective manner.

Optionally, the control device is configured to perform at least one of a corrective action and a safety action if the monitored change in the liquid level deviates from an expected change in the liquid level. Accordingly, it is possible to improve the operational safety of the washing appliance, thereby reducing the risk of problems such as overheating, fire, damage to components, flooding, and the like.

Optionally, the washing appliance comprises an output unit, and wherein the control device is configured to output a notification via the output unit if the monitored change in the liquid level deviates from an expected change in the liquid level. Accordingly, a washing appliance capable of notifying a user of detection of an operation error of the washing appliance is provided. In this way, the operational safety of the washing appliance may be improved by the user performing appropriate actions, and thereby the risk of subsequent problems such as overheating, fire, component damage, flooding, etc. may be reduced.

Optionally, the control device is configured to perform a corrective action if the monitored change in the liquid level deviates from an expected change in the liquid level, and wherein the corrective action comprises at least one of:

-changing the operating time of the washing cycle of the washing appliance,

-delaying the operating step of the washing cycle of the washing appliance, and

-changing the amount of liquid filled into the liquid container.

Accordingly, the operational safety of the washing appliance may be improved, and the risk of problems such as overheating, fire, damage to components, flooding, etc. may be reduced.

Optionally, the control device may be configured to perform at least partially limiting further operation of the washing appliance if the monitored change in the liquid level deviates from an expected change in the liquid level. Accordingly, the operational safety of the washing appliance may be improved, and the risk of problems such as overheating, fire, damage to components, flooding, etc. may be reduced.

According to a second aspect of the invention, the object is achieved by a method of detecting an operational error in a washing appliance, wherein the washing appliance comprises a liquid container configured to contain liquid, a level indicator unit configured to provide data indicative of a liquid level in the liquid container, a drain conduit, and a drain pump configured to drain the liquid container via the drain conduit,

and wherein the method comprises the steps of:

-operating the discharge pump during a first period of time,

-controlling the discharge pump to stop for a second period of time after the first period of time, and

-monitoring the change in the liquid level over the second period of time using data from the liquid level indicator unit.

Since the method comprises the step of monitoring the change in the liquid level during the second period of time, a method is provided which is capable of detecting the presence of a siphon effect in the discharge conduit in a simple and efficient manner. Furthermore, a method is provided which is capable of detecting whether liquid leaves the liquid container for some other reason, for example due to leakage.

Furthermore, a method is provided which is capable of detecting whether liquid leaves the liquid container in an unintended manner, while the washing appliance has conditions and characteristics suitable for being manufactured and assembled in a cost-effective manner. This is because such operational errors can be detected using a simple and low cost level indicator unit.

Accordingly, a method is provided to overcome or at least alleviate at least some of the above problems and disadvantages. Thus, the above object is achieved.

Optionally, the step of monitoring the change in the liquid level comprises the steps of:

-monitoring the change in liquid level in order to detect the presence of a siphon effect in the discharge conduit.

Thus, a method is provided which is capable of detecting a siphon effect in a discharge conduit in a simple and cost-effective manner. As a further result, the operational safety of the washing appliance can be improved and false decisions in the control logic of the washing appliance can be avoided, thus also avoiding potential subsequent problems such as overheating, fire risk, component damage, flooding, etc.

Optionally, the washing appliance comprises a circulation pump, and wherein the step of monitoring the change in the liquid level comprises the steps of:

-activating operation of the circulation pump, and

-monitoring one or more electrical quantities of the circulation pump.

Thus, a method is provided wherein a circulation pump is used as the liquid level indicator unit. In this way, the need for a separate sensor or device to sense the liquid level in the liquid container is avoided. Thus, due to these features, the method allows the washing appliance to have conditions and characteristics suitable for being manufactured and assembled in a cost-effective manner.

-detecting the liquid level at two or more points in time, an

-comparing the liquid levels detected at two or more points in time.

Thus, a simple and effective monitoring of the change of the liquid level is provided. Thus, due to these features, the method allows the washing appliance to have conditions and characteristics suitable for being manufactured and assembled in a cost-effective manner.

Optionally, the method further comprises:

-performing at least one of a corrective action and a safety action if the change in the monitored liquid level deviates from an expected change in the liquid level.

Accordingly, the operational safety of the washing appliance may be improved, thereby reducing the risk of problems such as overheating, fire, damage to components, flooding, and the like.

Optionally, the washing appliance comprises an output unit, and wherein the method comprises the steps of:

-outputting a notification via the output unit if the change in the monitored liquid level deviates from an expected change in the liquid level.

Thus, a method is provided that is capable of notifying a user of the detection of an operational error of a washing appliance. In this way, the operational safety of the washing appliance may be improved by the user performing appropriate actions, and thereby the risk of subsequent problems such as overheating, fire, component damage, flooding, etc. may be reduced.

Optionally, the method further comprises:

-performing a corrective action if the change in the monitored liquid level deviates from the expected change in the liquid level,

and wherein the corrective action comprises at least one of:

-changing the operating time of the washing cycle of the washing appliance,

-delaying the operating step of the washing cycle of the washing appliance, and

-changing the amount of liquid filled into the liquid container.

Optionally, the method further comprises:

-at least partially limiting further operation of the washing appliance if the monitored change in the liquid level deviates from the expected change in the liquid level.

According to a third aspect of the present invention, the object is achieved by a computer program comprising instructions which, when executed by a computer, cause the computer to perform a method according to some embodiments of the present disclosure. Since the computer program comprises instructions which, when the computer executes the program, cause the computer to perform the method according to some embodiments, a computer program is provided which provides conditions for overcoming or at least alleviating at least some of the disadvantages described above.

According to a fourth aspect of the present invention, the object is achieved by a computer-readable medium comprising instructions which, when executed by a computer, cause the computer to perform a method according to some embodiments of the present disclosure. Since the computer-readable medium comprises instructions which, when the program is executed by a computer, cause the computer to perform the method according to some embodiments, a computer-readable medium is provided which provides conditions for overcoming or at least alleviating at least some of the above disadvantages.

According to a fifth aspect of the invention, the object is achieved by a control device for a washing appliance, wherein the washing appliance comprises a liquid container configured to contain liquid, a liquid level indicator unit configured to provide data indicative of a liquid level in the liquid container, a drain conduit, and a drain pump configured to drain the liquid container via the drain conduit,

and wherein the control means is configured to:

-operating the discharge pump during a first time period,

Since the control means is configured to monitor the change in liquid level over the second period of time, a control means is provided which is capable of detecting the presence of a siphon effect in the discharge conduit in a simple and effective manner. Furthermore, a control device is provided which is able to detect whether liquid leaves the liquid container for some other reason, for example due to leakage.

Furthermore, a control device is provided which is capable of detecting whether liquid leaves the liquid container in an unintended manner, while the washing appliance has conditions and characteristics suitable for being manufactured and assembled in a cost-effective manner. This is because such operational errors can be detected using a simple and low cost level indicator unit.

As a further result thereof, conditions are provided for improving the operational safety of the washing appliance, for example by performing one or more appropriate actions if the monitored change in the liquid level deviates from the expected change in the liquid level.

Accordingly, a control device is provided to overcome or at least alleviate at least some of the above problems and disadvantages. Thus, the above object is achieved.

Further features of, and advantages with, the present invention will become apparent when studying the appended claims and the following detailed description.

Drawings

The various aspects of the invention, including the specific features and advantages thereof, will be best understood from the following detailed description and the accompanying drawings, in which:

figure 1 schematically illustrates a washing appliance according to some embodiments,

FIG. 2 illustrates a method of detecting an operational error in a washing appliance, according to some embodiments, and

FIG. 3 illustrates a computer-readable medium in accordance with some embodiments.

Detailed Description

Various aspects of the present invention will now be described more fully. Like numbers refer to like elements throughout. Well-known functions or constructions may not be described in detail for brevity and/or clarity.

Fig. 1 schematically illustrates a washing appliance 1 according to some embodiments of the present disclosure. According to the illustrated embodiment, the washing appliance 1 is a dishwasher 1. According to a further embodiment, the washing appliance 1 referred to herein may be another type of washing appliance 1, such as a washing machine. The washing appliance 1 comprises a washing chamber 2 configured to receive items to be washed. According to the illustrated embodiment, the washing appliance 1 comprises a washing compartment 2 configured to receive items (e.g., dishes, cutlery, etc.). Furthermore, according to the illustrated embodiment, the washing appliance 1 comprises a set of shelves 4, each configured to receive items to be washed in the washing chamber 2. According to the illustrated embodiment, the washing appliance 1 comprises three shelves 4. According to further embodiments, the washing appliance 1 may comprise other numbers of shelves 4, for example one or two shelves 4.

The washing appliance 1 comprises a plurality of spraying devices 6, which according to the illustrated embodiment are spraying arms 6. According to the illustrated embodiment, the washing appliance 1 comprises three spraying devices 6. According to further embodiments, the washing appliance 1 may comprise other numbers of spraying devices, such as one, two, four, five, etc. The washing appliance 1 further comprises a sump 3 located at the bottom of the washing chamber 2. The sump 3 is configured to contain washing liquid, such as a mixture of water and detergent, used in the washing process of the washing appliance 1. Accordingly, the sump 3 is referred to herein as a liquid container 3. Furthermore, the washing appliance 1 comprises a door 8, which is arranged to provide an enclosure of the washing chamber 2. In fig. 1, the door 8 is shown in a closed position. However, door 8 may be opened to an open position to access washing chamber 2.

The washing appliance 1 further comprises a circulation pump 7. The circulation pump 7 is configured to pump washing liquid from the liquid container 3 to the spraying device 6 via the hydraulic circuit 10 during a washing cycle of the dishwasher 1. The liquid is sprayed from the spraying device 6 onto the article to clean the article. Due to gravity, the liquid is collected in the liquid container 3, where it is pumped again to the spraying device 6 by the circulation pump 7.

The washing appliance 1 further comprises a liquid level indicator unit 5, 7 configured to provide data indicative of a liquid level 8 in the liquid container 3. According to some embodiments, the liquid level indicator unit 5 may comprise a sensor 5 configured to sense a liquid level 8 in the liquid container. Such sensors may include, for example, pressure switches, floats, weight measuring devices, and the like. Alternatively or additionally, the circulation pump 7 may be used as a level indicator unit 7 to provide data indicative of the liquid level 8 in the liquid container 3. According to such an embodiment, the data indicative of the liquid level 8 in the liquid container 3 may be obtained by operating the circulation pump 7 and monitoring one or more electrical quantities (e.g. current or voltage) of the circulation pump 7. As a further alternative or in addition to the above, the level indicator unit may comprise one or more flow sensors in the hydraulic circuit 10.

The washing appliance 1 further comprises a discharge conduit 15 and a discharge pump 13. The discharge pump 13 is configured to discharge the liquid container 3 via a discharge conduit 15. The drain conduit 15 is configured to connect to the drain 16 when the washing appliance 1 is installed. The discharge conduit 15 comprises a flexible hose 17 intended to be mounted such that the path of at least a part of the discharge conduit 15 passes through a point higher than the liquid container 3.

The washing appliance 1 further comprises control means 9. The control device 9 is configured to control the operation of the circulation pump 7 and the drain pump 13. Furthermore, the control device 9 may be configured to control the operation of further devices, systems, and/or subsystems of the washing appliance 1, such as one or more heating elements, one or more valve devices, etc.

According to embodiments herein, the control device 9 of the washing appliance 1 is configured to:

operating the discharge pump 13 during a first period of time,

-controlling the discharge pump 13 to be continuously stopped for a second period of time after the first period of time, and

monitoring the change of the liquid level 8 during the second time period using data from the liquid level indicator unit 5, 7.

Since the control means 9 is configured to monitor the change of the liquid level 8 during the second period of time, the change of the liquid level 8 during the period of time in which the drain pump 13 is not operating, i.e. during the second period of time, is monitored. Furthermore, since the second period follows the first period, the change in the liquid level 8 during the period in which the drain pump 13 has been recently operated, i.e. during the second period, is monitored. Thus, when the second time period begins, the discharge channel (e.g., discharge conduit 15) is filled with liquid. Thus, a washing appliance 1 is provided in which a control device 9 can monitor a change in the liquid level 8 in order to detect the presence of a siphon effect in the drain conduit 15, as explained further herein. In the above-described control routine executed by the control device 9, the second period may be started when the drain pump 13 reaches the stopped state. Further, the second time period may immediately follow the first time period. Since the drain pump 13 does not operate during the second period, the second period may also be referred to as a pause period of the drain pump 13.

When the discharge conduit 15 is filled with liquid, a siphon effect may occur in the discharge conduit 15, resulting in liquid being sucked out of the liquid container in an unintended manner, even when the discharge pump 13 is not operating. The siphon effect in the discharge conduit 15 may be due to the fact that: the discharge conduit 15 is mounted at a too low height with respect to the liquid container 3 and/or there is no free path between the discharge conduit 15 and the ambient air to achieve pressure equalization if the connection of the discharge conduit 15 to the discharge opening 16 is sealed.

In some cases, the siphon effect in the discharge conduit 15 may be due to the fact that the discharge conduit 15 becomes loose from the discharge connection. If so, a large amount of liquid may be drained inside/under cabinets and floors/walls. Furthermore, the siphon effect in the drain conduit 15 may lead to several false decisions in the control logic of the washing appliance and have potential subsequent problems, such as overheating, increased risk of fire, component damage, flooding, etc.

Since the control device 9 of the washing appliance 1 according to the present disclosure is configured to monitor the change of the liquid level 8 during the second period of time, a washing appliance 1 is provided which is capable of detecting the presence of a siphon effect in the drain conduit 15. Furthermore, a washing appliance 1 is provided which is capable of detecting whether liquid leaves the liquid container 3 for some other reason, for example due to leakage.

According to some embodiments, the control device 9 is configured to monitor the change in the liquid level 8 by detecting the liquid level 8 at two or more points in time within the second time period and comparing the liquid level 8 detected at the respective two or more points in time. According to a further embodiment, the control device 9 may be configured to continuously monitor the change of the liquid level 8.

As mentioned above, according to the illustrated embodiment, the control device 9 may be configured to monitor the change of the liquid level 8 and to monitor one or more electric quantities of the circulation pump 7 by operating the circulation pump 7. The charge of the circulation pump 7 indicates the liquid level 8, since a higher liquid level increases the pumping resistance and the duration of obtaining a higher pumping resistance, which in turn affects the charge of the circulation pump 7.

The control device 9 may be configured to compare the monitored change in the liquid level 8 with an expected change in the liquid level 8. As further explained herein, the control device 9 may be configured to perform at least one of a corrective action and a safety action if the monitored change in the liquid level 8 deviates from the expected change in the liquid level 8.

According to the illustrated embodiment, the washing appliance 1 comprises an output unit 11. The output unit 11 may include one or more of a display, a speaker, a communication module 11', and the like. The control device 9 may be configured to output a notification via the output unit 11 if the monitored change in the liquid level 8 deviates from the expected change in the liquid level 8. The output notification may be considered a security measure. According to the illustrated embodiment, the output unit 11 comprises a communication module 11' configured to wirelessly communicate with an external communication unit 22. The communication module 11' may be configured to wirelessly transmit data to and/or receive data from a remote wireless network router 22 (e.g., a Wi-Fi router). The wireless communication may be performed, for example, by a wireless connection such as the internet or a Wireless Local Area Network (WLAN), or a wireless connection for exchanging data over a short distance using a short wavelength, i.e., Ultra High Frequency (UHF) radio waves in the industrial, scientific, and medical (ISM) band from 2.4GHz to 2.485 GHz.

Furthermore, according to some embodiments of the present disclosure, the control device 9 may be configured to wirelessly output a notification to an external user device 26 (e.g., a computer, computer tablet, or mobile phone 26) via the output unit 11 if the monitored change in the liquid level 8 deviates from the expected change in the liquid level 8. Such wireless communication may be performed through a mobile communication network, a wireless network router 22, a Wireless Local Area Network (WLAN), or a wireless connection for exchanging data over a short distance using a short wavelength, i.e., Ultra High Frequency (UHF) radio waves in the industrial, scientific, and medical (ISM) band from 2.4GHz to 2.485 GHz. Furthermore, according to some embodiments of the present disclosure, the control device 9 may be configured to output a notification wirelessly to an external service center or service center personnel via the output unit 11.

According to some embodiments, the control device 9 may be configured to perform a corrective action if the monitored change in the liquid level 8 deviates from an expected change in the liquid level 8, and wherein the corrective action comprises at least one of:

changing the operating time of the washing cycle of the washing appliance 1,

-delaying the operating step of the washing cycle of the washing appliance 1, and

-varying the amount of liquid filled into the liquid container 3.

Alternatively or additionally, the control device 9 may be configured to perform at least partially limiting further operation of the washing appliance 1 if the monitored change in the liquid level 8 deviates from the expected change in the liquid level 8. According to some embodiments, the control device 9 may be configured to distinguish between changes in the liquid level 8 caused by a siphon effect and changes in the liquid level 8 caused by other causes. According to such an embodiment, the control device 9 may be configured to select a suitable measure based on the cause of the change in the liquid level 8.

The following are examples of possible controls performed by the control device 9. In the example, the liquid container 3 is drained and refilled between a first and a second wash cycle of the wash program. For example only, the liquid level is 4 liters at the end of the first wash cycle. The control means 9 operates the discharge pump 13 for a first period of time and terminates the operation of the discharge pump 13 when the expected pumped liquid volume is 1.5 litres, sufficient to fill the discharge channel and the discharge conduit 15 with liquid. The control means 9 then uses the data from the level indicator units 5, 7 to monitor the change in the liquid level 8 over the second period of time. As described above, the second period starts when the drain pump 13 is in the stopped state. In this example, the expected liquid level in the liquid container 3 is 2.5 liters and the expected change in the liquid level 8 is zero, at least for a period of time after the start of the second period of time. At the beginning of the second time period, the liquid level in the liquid container 3 is expected to rise. This is because it is expected that the liquid pumped in the first period will flow back from the discharge channel and discharge conduit 15 through the discharge pump 13 into the liquid container 3. If such a rise is not detected when monitoring a change in the liquid level 8 using data from the level indicator units 5, 7, a siphon effect can be expected in the discharge conduit 15. Furthermore, if the data provided by the level indicator units 5, 7 indicate that the liquid level 8 in the liquid container 3 is well below 2.5 litres in a period of time after the start of the second period of time, it can be expected that a siphon effect has occurred in the discharge conduit 15.

If more liquid is poured from the liquid container 3 than expected and the cause thereof is expected to be a siphon effect in the discharge conduit 15, the control means 9 may perform a pause until the siphon effect is expected to end and subsequently perform a complete filling of the liquid into the liquid container 3 instead of a partial filling of the liquid into the liquid container 3. The control means 3 may fill the liquid container 3 by opening a valve provided in the water inlet conduit. For the sake of brevity and clarity, the valve and water inlet conduit are not shown in fig. 1. The control device 9 may then continue the washing program by starting a second washing cycle and inform the user, the service center and/or the service center via the output unit 11 that the installation of the discharge conduit 15 should be checked.

Fig. 2 illustrates a method 100 of detecting an operational error in a washing appliance. The method 100 may be performed in a washing appliance 1 according to the embodiment illustrated in fig. 1. Accordingly, reference is made to fig. 1 and 2 concurrently hereinafter. The method illustrated in fig. 2 is a method 100 of detecting an operational error in a washing appliance 1, wherein the washing appliance 1 comprises a liquid container 3 configured to contain liquid, a liquid level indicator unit 5, 7 configured to provide data indicative of a liquid level 8 in the liquid container 3, a drain conduit 15, and a drain pump 13 configured to drain the liquid container 3 via the drain conduit 15,

and wherein the method 100 comprises the steps of:

operating 110 the discharge pump 13 during a first time period,

-controlling 120 the discharge pump 13 to be continuously stopped for a second period of time after the first period of time, and

monitoring 130 the change in the liquid level 8 during the second time period using data from the liquid level indicator unit 5, 7.

As shown in FIG. 2, the step of monitoring 130 the change in level 8 may include the steps of:

monitoring 131 the change of the liquid level 8 in order to detect the presence of a siphon effect in the discharge conduit 15.

According to some embodiments, the washing appliance 1 comprises a circulation pump 7, and as shown in fig. 2, the step of monitoring 130 the change in the liquid level 8 may comprise the steps of:

-activating 132 the operation of the circulation pump 7, and

monitoring 133 one or more electrical quantities of the circulation pump 7.

Further, as shown in FIG. 2, the step of monitoring 130 the change in the level 8 may include the steps of:

detecting 134 the liquid level 8 at two or more points in time, an

-comparing 135 the liquid levels 8 detected at two or more points in time.

Furthermore, as shown in fig. 2, the method 100 may further include the steps of:

-if the monitored change in the liquid level 8 deviates from the expected change in the liquid level 8, performing 140 at least one of a corrective action and a safety action.

According to some embodiments, the washing appliance 1 comprises an output unit 11, and as shown in fig. 2, the method 100 may comprise the steps of:

-outputting 150 a notification via the output unit 11 if the monitored change in the liquid level 8 deviates from the expected change in the liquid level 8.

In addition, as shown in fig. 2, the method may further include the steps of:

-if the monitored change in the liquid level 8 deviates from the expected change in the liquid level 8, performing 141 a corrective action,

and wherein the corrective action comprises at least one of:

-changing 142 the operating time of the washing cycle of the washing appliance 1,

-delaying 143 the operating step of the washing cycle of the washing appliance 1, and

-varying 144 the amount of liquid filled into the liquid container 3.

In addition, as shown in fig. 2, the method may further include the steps of:

-at least partially limiting 145 further operation of the washing appliance 1 if the monitored change in the liquid level 8 deviates from the expected change in the liquid level 8.

It is to be understood that the various embodiments described for the method 100 may be combined with the control device 9 described herein. That is, the control device 9 may be configured to perform any one of the method steps 110, 120, 130, 131, 132, 133, 134, 135, 140, 141, 142, 143, 144, 145 and 150 of the method 100.

Fig. 3 illustrates a computer-readable medium 200 comprising instructions that, when executed by a computer, cause the computer to perform the method 100 according to some embodiments of the present disclosure.

According to some embodiments, the computer-readable medium 200 comprises a computer program comprising instructions which, when executed by a computer, cause the computer to perform the method 100 according to some embodiments.

Those skilled in the art will appreciate that the method 100 of detecting an operational error in the washing appliance 1 may be implemented by programmed instructions. These programming instructions are typically constituted by a computer program which, when executed in the control device 9, ensures that the control device 9 performs the desired control, such as the method steps 110, 120, 130, 131, 132, 133, 134, 135, 140, 141, 142, 143, 144, 145 and 150 described herein. The computer program is typically part of a computer program product 200 comprising a suitable digital storage medium on which the computer program is stored.

The control device 9 may include a computing unit, which may take the form of substantially any suitable type of processor circuit or microcomputer, such as circuitry for digital signal processing (digital signal processor, DSP), a Central Processing Unit (CPU), a processing unit, processing circuitry, a processor, an Application Specific Integrated Circuit (ASIC), a microprocessor, or other processing logic that may interpret and execute instructions. The expression "computing unit" as used herein may denote processing circuitry comprising a plurality of processing circuits, e.g. any, some or all of the processing circuits described above.

The control device 9 may further comprise a memory unit, wherein the calculation unit may be connected to the memory unit, which may provide the calculation unit with e.g. stored program code and/or stored data which the calculation unit may need to enable the calculation. The calculation unit may further be adapted to store a part of the calculation or the final result in the memory unit. A memory unit may comprise a physical device used for temporarily or permanently storing data or a program (i.e. a sequence of instructions). According to some embodiments, the memory cells may comprise integrated circuits comprising silicon-based transistors. In different embodiments, the memory unit may comprise, for example, a memory card, a flash memory, a USB memory, a hard disk, or another similar volatile or non-volatile memory unit for storing data, such as a ROM (read only memory), a PROM (programmable read only memory), an EPROM (erasable PROM), an EEPROM (electrically erasable PROM), or the like.

The control device 9 is connected to the components of the washing appliance 1 for receiving and/or sending input signals and output signals. These input and output signals may comprise waveforms, pulses or other properties which the input signal receiving means may detect as information and may convert into signals which may be processed by the control means 9. These signals can then be supplied to a computing unit. One or more output signal transmission means may be arranged to convert the calculation results from the calculation unit into output signals for communication to other parts of the control system of the washing appliance 1 and/or to the component or components to which the signals are directed. Each of the connections with the respective components of the washing appliance 1 for sending and receiving input and output signals may take the form of one or more of a cable, a wireless connection, etc.

In the illustrated embodiment, the washing appliance 1 comprises a control device 9, but may alternatively be implemented wholly or partly in two or more control devices or two or more control units.

The computer program product 200 may be provided, for example, in the form of a data carrier carrying computer program code for performing at least some of the method steps 110, 120, 130, 131, 132, 133, 134, 135, 140, 141, 142, 143, 144, 145 and 150 according to some embodiments when being loaded into one or more computing units of the control device 9. The data carrier may be, for example, a CD ROM disc as shown in fig. 3, or a ROM (read only memory), PROM (programmable read only memory), EPROM (erasable PROM), flash memory, EEPROM (electrically erasable PROM), hard disk, a memory stick, an optical storage device, a magnetic storage device, or any other suitable medium, such as an optical disc or a magnetic tape, which may hold machine-readable data in a non-transitory manner. Furthermore, the computer program product may also be provided as computer program code on a server and may be downloaded to the control means 9 remotely, e.g. via an internet or intranet connection, or via other wired or wireless communication systems.

As indicated above, according to the illustrated embodiment, the washing appliance 1 comprises a liquid container 3 in the form of a sump 3. Thus, throughout this disclosure, the term "liquid container" may be replaced by the term "sump".

It should be understood that the foregoing is illustrative of various exemplary embodiments and that the invention is limited only by the claims which follow. Those skilled in the art realize that the exemplary embodiments can be modified and different features of the exemplary embodiments can be combined to create embodiments other than those described herein, without departing from the scope of the present invention as defined by the appended claims.

As used herein, the terms "comprises" or "comprising" are open-ended and include one or more stated features, elements, steps, components, or functions without precluding the presence or addition of one or more other features, elements, steps, components, functions, or groups thereof.

Claims

1. A washing appliance (1) comprising:

a liquid container (3) configured to contain a liquid,

a liquid level indicator unit (5, 7) configured to provide data indicative of a liquid level (8) in the liquid container (3),

-a discharge conduit (15), and

-a discharge pump (13) configured to discharge the liquid container (3) via the discharge conduit (15),

and wherein the washing appliance (1) further comprises a control device (9) configured to:

-operating the discharge pump (13) during a first period of time,

-controlling the discharge pump (13) to stop for a second period of time after the first period of time, and

-monitoring the change of the liquid level (8) during the second period of time using data from the liquid level indicator unit (5, 7).

2. Washing appliance (1) according to claim 1, wherein the liquid is a washing liquid used in a washing process of the washing appliance (1).

3. The washing appliance (1) according to claim 1 or 2, wherein the control device (9) is configured to monitor a change in the liquid level (8) in order to detect the presence of a siphon effect in the discharge conduit (15).

4. The washing appliance (1) according to any of the preceding claims, wherein the control device (9) is configured to monitor the change of the liquid level (8) by detecting the liquid level (8) at two or more points in time and comparing the liquid levels (8) detected at the respective two or more points in time.

5. The washing appliance (1) according to any of the preceding claims, wherein the control device (9) is configured to perform at least one of a corrective action and a safety action if the monitored change of the liquid level (8) deviates from an expected change of the liquid level (8).

6. The washing appliance (1) according to any of the preceding claims, wherein the washing appliance (1) comprises an output unit (11), and wherein the control device (9) is configured to output a notification via the output unit (11) if the monitored change in the liquid level (8) deviates from an expected change in the liquid level (8).

7. The washing appliance (1) according to any of the preceding claims, wherein the control device (9) is configured to perform a corrective action if the monitored change in the liquid level (8) deviates from an expected change in the liquid level (8), and wherein the corrective action comprises at least one of:

-varying the operating time of the washing cycle of the washing appliance (1),

-delaying the operating step of the washing cycle of the washing appliance (1), and

-varying the amount of liquid filled into the liquid container (3).

8. A method (100) of detecting an operational error in a washing appliance (1), wherein the washing appliance (1) comprises a liquid container (3) configured to contain liquid, a liquid level indicator unit (5, 7) configured to provide data indicative of a liquid level (8) in the liquid container (3), a drain conduit (15), and a drain pump (13) configured to drain the liquid container (3) via the drain conduit (15),

and wherein the method (100) comprises the steps of:

-operating (110) the discharge pump (13) during a first period of time,

-controlling (120) the discharge pump (13) to stop for a second time period after the first time period, and

-monitoring (130) a change in the liquid level (8) over the second time period using data from the liquid level indicator unit (5, 7).

9. The method (100) of claim 8, wherein the step of monitoring (130) the change in the liquid level (8) comprises the steps of:

-monitoring (131) the change of the liquid level (8) in order to detect the presence of a siphon effect in the discharge conduit (15).

10. Method (100) according to claim 8 or 9, wherein the step of monitoring (130) the change of the liquid level (8) comprises the steps of:

-detecting (134) the liquid level (8) at two or more points in time, and

-comparing (135) the liquid level (8) detected at the two or more points in time.

11. The method (100) according to any one of claims 8 to 10, wherein the method (100) further comprises:

-performing (140) at least one of a corrective action and a safety action if the monitored change in the liquid level (8) deviates from the expected change in the liquid level (8).

12. The method (100) according to any of claims 8 to 11, wherein the washing appliance (1) comprises an output unit (11), and wherein the method (100) comprises the steps of:

-outputting (150) a notification via the output unit (11) if the monitored change of the liquid level (8) deviates from an expected change of the liquid level (8).

13. The method (100) according to any one of claims 8 to 12, wherein the method further comprises:

-performing (141) a corrective action if the monitored change in the liquid level (8) deviates from an expected change in the liquid level (8),

and wherein the corrective action comprises at least one of:

-changing (142) the operating time of the washing cycle of the washing appliance (1),

-delaying (143) the operating steps of the washing cycle of the washing appliance (1), and

-changing (144) the amount of liquid filled into the liquid container (3).

14. A computer program comprising instructions which, when executed by a computer, cause the computer to perform the method (100) according to any one of claims 8 to 13.

15. A computer-readable medium (200) comprising instructions which, when executed by a computer, cause the computer to perform the method (100) according to any one of claims 8 to 13.