DEVICE

Technical field

The inventive concept described herein generally relates to water recirculating devices.

Background

In many parts of the world, clean water is becoming a scarce commodity. Consequently, systems for purification and recycling of water has found applications across many fields. Such systems can be effective, however, they often require frequent maintenance in order to secure an acceptable hygiene within the device itself. The development of filter technology further adds to the problem when more water is able to be recirculated, while filtering more contaminants and microorganisms from the recirculated water.

There is therefore a need for improved water recirculating devices with respect to hygienic properties, and effectiveness.

Summary of the invention

It is an object of the present inventive concept to mitigate, alleviate or eliminate one or more of the above-identified deficiencies in the art and disadvantages singly or in combination.

According to a first aspect of the inventive concept, these and other objects are achieved in full, or at least in part, by a method for determining an object type being subjected to a water recirculating device comprising: an outlet configured to output water; a collecting arrangement arranged to collect water output by the outlet; and a discard path configured to discard water from the water recirculating device; wherein the method comprises: receiving presence sensor data from a presence sensor arrangement of the water recirculating device; determining whether the object type is human based on the presence sensor data; and if the object type is human, setting the water recirculating device in a recirculation mode, else setting the water

recirculating device in a discard mode.

The water recirculating device may comprise a water quality sensor arrangement configured to collect water quality data of water collected by the collecting arrangement, and wherein the recirculation mode comprises:

receiving the water quality data from the water quality sensor arrangement; determining the water quality measure of the water collected by the collecting arrangement based on the water quality data; if the water quality measure is below a first water quality threshold, discarding the water collected by the collecting arrangement; and if the water quality measure is equal to or above the first water quality threshold, recirculating at least part of the water collected by the collecting arrangement, and wherein the discard mode comprises: discarding the water collected by the collecting arrangement.

The step of determining whether the object type is human may be further based on the water quality data.

The method may further comprise associating the determination of the object type with a time stamp, wherein the step of determining whether the object type is human is further based on historical data pertaining to previous determinations of object types and respective previous time stamps.

The method may further comprise, if the object type is human, determining whether a fall has occurred based on the presence sensor data.

The presence sensor arrangement may comprise an infrared sensor.

The presence sensor arrangement may comprise an array of light receiving elements.

The presence sensor arrangement may comprise an accelerometer and/or a force sensor.

The method may further comprise, if the object type is human, determining a number of objects subjected to the water recirculating device based on the presence sensor data, and if the number of objects is less than two, setting the water recirculating device in the recirculation mode, else setting the water recirculating device in the discard mode.

The water recirculating device may be a water recirculating shower.

According to a second aspect of the inventive concept, these and other objects are achieved in full, or at least in part, by a water recirculating device comprising: an outlet configured to output water; a collecting arrangement arranged to collect water output by the outlet; and a discard path configured to discard water from the water recirculating device; a presence sensor arrangement configured to collect presence sensor data; a computing unit configured to receive presence sensor data and to determine whether an object type being subjected to the water recirculating device is human based on the presence sensor data; wherein the water recirculating device is configured to be set in a recirculation mode if the object type is human, and else to be set in a discard mode.

The water recirculating device may further comprise a water quality sensor arrangement configured to collect water quality data of water collected by the collecting arrangement, wherein the computing unit is further configured to receive the water quality data from the sensor arrangement and to determine a water quality measure based on the water quality data, wherein the water recirculating device is configured to, in the recirculation mode, if the water quality measure is below a first water quality threshold, discard the water, and if the water quality measure is equal to or above the first water quality threshold, recirculate at least part of the water, and wherein the water recirculating device is configured to, in the discard mode, discard the water collected by the collecting arrangement.

The computing unit may be configured to, if the object type is human, determine whether a fall has occurred in relation to the water recycling device based on the presence sensor data.

The presence sensor arrangement may comprise an infrared sensor.

The presence sensor arrangement may comprise an accelerometer and/or a force sensor and/or a vibration sensor.

The water recirculating device may be a shower.

A feature described in relation to one aspect may also be incorporated in other aspects, and the advantage of the feature is applicable to all aspects in which it is incorporated.

Other objectives, features and advantages of the present inventive concept will appear from the following detailed disclosure, from the attached claims as well as from the drawings.

Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. Further, the use of terms "first", "second", and "third", and the like, herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. All references to "a/an/the [element, device, component, means, step, etc]" are to be interpreted openly as referring to at least one instance of said element, device, component, means, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated. Brief description of the drawings

The above, as well as additional objects, features and advantages of the present inventive concept, will be better understood through the following illustrative and non-limiting detailed description of different embodiments of the present inventive concept, with reference to the appended drawings, wherein:

FIG. 1 schematically illustrates a water recirculating device;

FIG. 2 is a flow chart of a method for determining an object type being subjected to a water recirculating device;

FIG. 3 is a flow chart illustrating fall monitoring in relation to a water recirculating device.

FIGS. 4a - 4g illustrates water recirculating devices and examples of objects being subjected to a water recirculating device.

FIG. 5 is a flow chart of a method for determining an object type being subjected to a water recirculating device.

Detailed description

The present disclosure relates to water recirculating devices. Initially, some terminology may be defined to provide clarification for the following disclosure.

Throughout the present disclosure, reference is made to paths. Such paths may be for example pipes for transporting water.

Throughout the present disclosure, references are made to features being arranged "downstream" and/or "upstream" of certain features. The flow direction to which the terms "downstream" and "upstream" refer should be understood to be a flow direction from the collecting arrangement to the outlet. In other words, the "stream" referred to in the terms "downstream" and "upstream" is a stream flowing from the collecting arrangement to the outlet.

Throughout the present disclosure, references are made to object types being subjected to a water recirculating device. Such an object type may be a human being. The object type may also comprise animals, such as a dog or a cat, household items, and/or any other item capable of being subjected to a water recirculating device. In some cases, the object being subjected to the water recirculating device is also the user of the water recirculating device.

In general, the inventive concept contributes to the effectiveness of a water recirculating device in terms of hygiene and reduction of water consumption. This is achieved by determining whether a human is subjected to the water recirculating device, or whether another object is subjected to the water recirculating device. Hereby, the water recirculating device can be set in an appropriate mode e.g. a discard mode in order to spare the use of recirculating parts of the water recirculating device.

FIG. 1 illustrates a water recirculating device 100 comprising: an outlet

102 configured to output water; a collecting arrangement 104 arranged to collect water output by the outlet 102; a discard path 106 configured to discard water from the water recirculating device 100.

The water recirculating device 100 may comprise a pump 108 for providing a flow of water in the water recirculating device 100.

The water recirculating device 100 may comprise a water treatment arrangement 1 10. The water treatment arrangement 1 10 may comprise a filter arrangement and/or a UV light treatment arrangement.

The water recirculating device 100 may comprise a heating

arrangement 1 12. The heating arrangement 1 12 may be configured to heat water passing the heating arrangement 1 12.

The water recirculating device 100 may comprise a water quality sensor arrangement 1 14. The water quality sensor arrangement 1 14 may comprise an electrical conductivity sensor and/or a UV-sensor, and/or a turbidity sensor. The water quality sensor arrangement 1 14 may be configured to collect water quality data of water collected by the collecting arrangement. It should be noted that the water quality sensor arrangement 1 14 is here for the sake of clarity illustrated as a box arranged between the collecting arrangement 1 04 and outlet 102, however, the water quality sensor arrangement may be arranged e.g. in the collecting arrangement 1 04, such that a water quality data of water in the collecting arrangement 104 may be collected.

The water recirculating device 100 may comprise an external water path 1 18 connected to an external water source. Hereby, external water may be fed to the water recirculating device 100.

The water recirculating device 100 comprises a presence sensor arrangement 1 16a, 1 16b, 1 16c. The presence sensor arrangement 1 16a, 1 16b, 1 16c may be configured to collect presence sensor data. The presence sensor arrangement may comprise an infrared sensor, and/or a light receiving element, and/or an array of light receiving elements 1 16a, 1 16b. The presence sensor arrangement may comprise an electromagnetic radiation receiving sensor. The presence sensor arrangement may comprise an acoustic vibration receiving sensor. The presence sensor arrangement may comprise an accelerometer, and/or a force sensor, and/or a vibration sensor 1 16c. The accelerometer, and/or a force sensor, and/or a vibration sensor 1 16c may be placed in or at a supporting surface 120 being in proximity of the water recirculating device 100. The supporting surface 120 may be a floor of a shower cabin. The presence sensor arrangement may be placed in a ceiling of a room wherein the water recirculating device 100 is placed. The presence sensor arrangement may be placed on or near the supporting surface 120 on which an object is intended to be placed when being subjected to the water recirculating device 100. The presence sensor arrangement may receive presence sensor data as a result of the object type interacting with the presence sensor arrangement. The presence sensor arrangement may comprise a sensor based on capacitive effects

The water recirculating device 100 may be configured to be set in a recirculation mode and a discard mode. The recirculation mode may comprise receiving water quality data from the water quality sensor arrangement 1 14 and determining a water quality measure of water collected by the collecting arrangement 104 based on the water quality data. Further, if the water quality measure of the water collected by the collecting arrangement 104 is below a first water quality threshold, the water collected by the collecting arrangement 104 may be discarded via the discard path 106. If water collected by the collecting arrangement 1 04 is discarded via the discard path 106, external water may be fed to the water recirculating device 100 via the external water path 1 18. Hereby, a flow rate of water being output by the outlet 102 may be kept substantially constant.

If the water quality measure of the water collected by the collecting arrangement 104 is equal to or above the first water quality threshold, at least part of the water collected by the collecting arrangement 104 may be recirculated. Hereby, water collected by the collecting arrangement may be reused and output by the outlet 102. If part of the water collected by the collecting arrangement 1 04 is recirculated, external water may be fed to the water recirculating device 100 via the external water path 1 18. Hereby, a flow rate of water being output by the outlet 102 may be kept substantially constant.

The discard mode may comprise discarding the water collected by the collecting arrangement 1 04. The discard mode may comprise providing external water to the water recirculating device 100 via the external water path 1 18.

Referring now to FIG. 2, a flow chart illustrating, inter alia, a method for determining an object type being subjected to a water recirculating device is shown. Presence sensor data is received from the presence sensor arrangement of the water recirculating device at 222. The presence sensor arrangement may comprise an array of light receiving elements, and/or an infrared sensor. The presence sensor arrangement may comprise an accelerometer and/or a force sensor.

By way of example, some possible scenarios of how an object type being subjected to a water recirculating device is determined will now be described.

For example, a light receiving element may detect a change of intensity in received light as a result of a person or an object entering a proximity of the water recirculating device. Hereby, a human being may be differentiated from another object type by e.g. a thermal profile, and/or a body temperature, as detected by an infrared sensor.

It may also be possible for the presence sensor arrangement to determine a height of an object being subjected to the water recirculating device. Hereby, a human being may be differentiated from another object type.

Further, a movement pattern of the object being subjected to the water recirculating device may be determined. This may for example be possible by using the accelerometer and/or force sensor, and/or by using the light receiving element and/or infrared sensor. Hereby, a human being may be differentiated from another object type.

Further, the presence sensor arrangement may comprise a scale, thus providing the possibility the detect a weight of the object being subjected to the water recirculating device. Hereby, a human being may be differentiated from another object type.

Further, water quality data from the water quality sensor arrangement may be received at 224. The water quality data may indicate whether the object type being subjected to the water recirculating device is a human, or another object type. For example, water exiting the outlet of the water recirculating device may contact a person being subjected to the water recirculating device, thus allowing biological material, substances, and/or other types of substances to travel with the output water to the collecting arrangement wherein the output water is collected and subsequently analyzed by the water quality sensor arrangement. Such biological material, substances, and/or other types of substances may for example be unique to human beings, and therefore indicative of a human being subjected to the water recirculating device, as opposed to another object type, such as e.g. an animal or a household item.

The determination of the object type may be associated with a time stamp. The time stamp may comprise a time of day, a day of the week, month, and/or year. For example, if the object type is determined to be human, the determination may be associated with a time stamp indicating that the human was subjected to the water recirculating device at 8.00 am on a Monday the first week of July, 2017. Such information is here referred to as historical data pertaining to previous determinations of object types and respective previous time stamps. The historical data may be used for future determinations of object types being subjected to the water recycling device at 226.

In general, by utilizing several sensors and/or sources of data, the determination of the object type being subjected to the water recirculating device may be performed with a high level of reliability.

Still referring to FIG. 2, if the object type is determined to be human at

228 and 230, the water recycling device is set in a recirculation mode at 238. In contrast, if the object type is determined to no be a human, e.g. to be another object type, the water recirculation device is set in a discard mode at 240.

If the object type is determined to be human, a number of objects subjected to the water recirculating device may be determined based on the presence sensor data at 234 and 236. It is to be understood that several objects may be subjected to the water recirculating device, e.g. a human and another object, or several humans. One example of several humans being subjected to a water recirculating device is public showers wherein several outlets may be connected to a single water collecting arrangement. Thus, water collected from several outputs which have been in contact with several different human users, is mixed in the collecting arrangement. In this case, setting the water recirculating device in a discard mode may be preferable.

Consequently, if the determined number of objects is less than two, such as one, the water recirculating device may be set in a recirculation mode. Else, the water recirculating device may be set in a discard mode. A fall monitoring may be performed at 232 if the determined object type is human. An example of a fall monitoring is illustrated in FIG. 3. The fall monitoring may utilize the presence sensor arrangement at 342 in order to determine whether a fall has occurred at 344. For example, a person slipping in the shower may be detected by the presence sensor arrangement via any of the sensor comprised in the presence sensor arrangement, such as an accelerometer arranged in a supporting surface such as a floor of a shower cabin. The accelerometer may in the case of a fall register an impulse caused by a person falling to the floor. A single light receiving element or an array of light receiving elements may also be able to register a person falling to the floor. If a fall is detected, an alert may be sent at 346 by the water

recirculating device to an external system, such as emergency services.

It can be noted that reliability is of high importance in the field of water recirculating devices with respect to water quality and performance. Further, the determination of object type according to the inventive concept may be made with a certain reliability. In other words, a determination may be made that the object type is human with a reliability value. The reliability value may be compared to a reliability threshold, and if the reliability value is below the reliability threshold, the water recirculating device may be set in a discard mode. It is to be understood that the reliability threshold may vary between different applications.

A current mode of the water recirculating device, i.e. recirculation mode or discard mode, may be displayed on a user interface of the water recirculation device. The water recirculating device may be configured to receive user input via the user interface. The water recirculating device may be configured to receive an override command via the user interface in order to change a mode of the water recirculating device, i.e. switch from discard mode to recirculation mode or vice versa.

Some scenarios related to the presence sensor arrangement and different object types will now be described by way of example with reference to FIGS. 4a-4g. It is to be understood that some features have been separated for the sake of clarity, and that the illustrated examples can be combined within the scope of the inventive concept.

Referring now to FIG. 4a, a water recirculating device 400a is illustrated comprising a presence sensor arrangement. The presence sensor arrangement here comprises a light receiving element, such as an infrared sensor. The light receiving element is top mounted, and an example of a sensing volume resulting from such an arrangement is shown.

Referring now to FIG. 4b, a water recirculating device 400b is illustrated comprising a presence sensor arrangement. The presence sensor arrangement here comprises a light receiving element, such as an infrared sensor. The light receiving element is side mounted, and an example of a sensing volume resulting from such an arrangement is shown.

Referring now to FIG. 4c, a water recirculating device 400c is illustrated. A human 448 is subjected to the water recirculating device 400c.

Referring now to FIG. 4d, a water recirculating device 400d is illustrated. An unidentified object 450 is subjected to the water recirculating device 400d. According to the inventive concept, it may be sufficient to determine whether the object type is a human or not. Thus, if it has been determined that the object type is not human, it may not be required to further determine the specific object type.

Referring now to FIG. 4e, a water recirculating device 400e is illustrated. Two humans 452, 454 are here being subjected to the water recirculating device 400e. As described earlier in the present disclosure, several humans may be subjected to a water recirculating device having more than one output (not shown).

Referring now to FIG. 4f, a water recirculating device 400f is illustrated. An animal 456 is subjected to the water recirculating device 400f.

Referring now to FIG. 4g, a water recirculating device 400g is illustrated. A human 458 has fallen while being subjected to the water recirculating device 400g. The presence sensor arrangement may determine that a fall has occurred, and may send an alert to an external system.

Referring now to FIG. 5, a method for determining an object type being subjected to a water recirculating device is illustrated in a flow chart. The method comprises a step 560 of receiving presence sensor data from a presence sensor arrangement of the water recirculating device, a step 562 of determining whether the object type is human based on the presence sensor data, and a step 564 of, if the object type is human, setting the water recirculating device in a recirculation mode, else setting the water

recirculating device in a discard mode.

The inventive concept has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the inventive concept, as defined by the appended patent claims.

List of reference signs

100 Water recirculating device

102 Outlet

104 Collecting arrangement

106 Discard path

108 Pump

1 10 Water treatment arrangement

1 12 Heating arrangement

1 14 Water quality sensor arrangement

1 16a Presence sensor arrangement

1 16b Presence sensor arrangement

1 16c Presence sensor arrangement

1 18 External water path

120 Supporting surface

222 Step of receiving presence sensor data

224 Step of receiving water quality sensor data

226 Step of receiving historical data

228 Step of determining object type

230 Step of determining object type

232 Step of performing fall monitoring

234 Step of determining number of human objects

236 Step of determining number of human objects

238 Step of setting recirculation mode

240 Step of setting discard mode

342 Step of receiving presence sensor data

344 Step of determining whether a fall has occurred

346 Step of sending alert

400a Water recirculating device

400b "

400c "

400d "

400e "

400f "

400g "

448 Human object

450 Unidentified object

452 Human Human

Animal

Human

Step of receiving presence sensor data Step of determining object type

Step of setting water recirculating device mode

The disclosure made in the following paragraphs relates to a related aspect of the inventive concept presented above.

The inventive concept described below generally relates to water recirculating devices.

5 In many parts of the world, clean water is becoming a scarce

commodity. Consequently, systems for purification and recycling of water has found applications across many fields. Such systems can be effective, however, they often require frequent maintenance in order to secure an acceptable hygiene within the device itself. The development of filter

o technology further adds to the problem when more water is able to be

recirculated, while filtering more contaminants and microorganisms from the recirculated water.

There is therefore a need for improved water recirculating devices with respect to hygienic properties, and effectiveness.

5 It is an object of the inventive concept to mitigate, alleviate or eliminate one or more of the above-identified deficiencies in the art and disadvantages singly or in combination.

According to a first aspect of the inventive concept, these and other objects are achieved in full, or at least in part, by a method for identifying an o end of a user sequence of a water recirculating device, the water recirculating device comprising: an outlet configured to output water; a collecting arrangement arranged to collect water output by the outlet; a recirculating path in liquid communication with the outlet and the collecting arrangement; and a discard path configured to discard water from the water recirculating 5 device; wherein the method comprises: receiving presence sensor data from a presence sensor arrangement of the water recirculating device; identifying the end of the user sequence based on the presence sensor data; and performing a cleaning procedure of the water recirculating device.

The presence sensor arrangement may comprise an infrared sensor. 0 The presence sensor arrangement may comprise an array of light receiving elements.

The presence sensor arrangement may comprise an accelerometer and/or a force sensor arranged in the water recirculating device.

The user sequence may comprise a start time and an end time,

5 wherein the presence sensor arrangement is configured to determine a user sequence duration elapsed based on the start and end time, and wherein the step of identifying the end of the user sequence is further based on the user sequence duration.

The user sequence may comprise at least one sub-user sequence, and wherein the presence sensor arrangement is configured to determine an intermission duration elapsed from an end of the sub-user sequence, and wherein the step of identifying the end of the user sequence is further based on the intermission duration.

The presence sensor data may comprise data generated by a user input actuation triggered via a user interface of the water recycling device, and wherein the step of identifying the end of the user sequence is further based on the user input actuation.

The water recycling device may comprise a water quality sensor arrangement configured to collect water quality data of water collected by the collecting arrangement, and wherein the step of identifying the end of the user sequence is further based on the water quality data.

The cleaning procedure may comprise at least partly draining the water recirculating device of water.

The cleaning procedure may comprise heating water in the water recirculating device by a heating arrangement of the water recirculating device.

According to a second aspect of the inventive concept, these and other objects are achieved in full, or at least in part, by a water recirculating device comprising: an outlet configured to output water; a collecting arrangement arranged to collect water output by the outlet; a recirculating path in liquid communication with the outlet and the collecting arrangement; a discard path configured to discard water from the water recirculating device; a presence sensor arrangement configured to collect presence sensor data; and a computing unit configured to receive presence sensor data and to identify an end of a user sequence of the water recirculating device based on the presence sensor data, and to perform a cleaning procedure of the water recirculating device.

The water recirculating device may be integrated into a hair wash comprising a seating area, and wherein the presence sensor arrangement comprises an accelerometer and/or a force sensor arranged in the seating area.

The water recirculating device may be a water recirculating shower. A feature described in relation to one aspect may also be incorporated in other aspects, and the advantage of the feature is applicable to all aspects in which it is incorporated.

Other objectives, features and advantages of the present inventive concept will appear from the following detailed disclosure, from the attached claims as well as from the drawings.

Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. Further, the use of terms "first", "second", and "third", and the like, herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. All references to "a/an/the [element, device, component, means, step, etc]" are to be interpreted openly as referring to at least one instance of said element, device, component, means, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.

The above, as well as additional objects, features and advantages of the present inventive concept, will be better understood through the following illustrative and non-limiting detailed description of different embodiments of the present inventive concept, with reference to the appended drawings, wherein:

FIG. 1 1 schematically illustrates an example of a water recirculating device;

FIGS. 12a and 12b schematically illustrate examples of a water recirculating device;

FIGS. 13a and 13b schematically illustrates examples of a presence sensor arrangement in a water recirculating device;

FIG. 14a - 14d illustrate flowrate, presence sensor data, water quality data, and user sequences in a water recirculating device over time;

FIG. 15 is a flow chart of a method for identifying an end of a user sequence of a water recirculating device.

The present disclosure relates to [technical field]. Initially, some terminology may be defined to provide clarification for the following disclosure.

Throughout the present disclosure, reference is made to paths. Such paths may be for example pipes for transporting water. Throughout the present disclosure, references are made to features being arranged "downstream" and/or "upstream" of certain features. The flow direction to which the terms "downstream" and "upstream" refer should be understood to be a flow direction from the collecting arrangement to the outlet. In other words, the "stream" referred to in the terms "downstream" and "upstream" is a stream flowing from the collecting arrangement to the outlet.

Throughout the present disclosure, references are made to user sequences. Such a user sequence may comprise at least one sub-user sequence. In the context of a water recirculating shower, a sub-user sequence may be a use of the water recirculating device in order to wet the hair of the user. A subsequent sub-user sequence may be a use of the water recirculating device in order to shampoo the hair of the user. Yet another subsequent sub-user sequence may be a use of the water recirculating device in order to rinse the hair of the user. The above described sub-user sequences may form a full user sequence. As is readily appreciated by the person skilled in the art, other sub-user sequences and user sequences may be envisaged within the scope of the inventive concept.

In some water recirculating devices, it may be preferable to perform a cleaning procedure between different users in order to ensure hygienic properties of the water recirculating device. Further, it may be preferable to drain the water recirculating device after use in order to ensure hygienic properties of the water recirculating device. Hygienic properties may relate to growth of microorganisms such as bacteria within the water recirculating device. In other words, a cleaning procedure may be performed in order to decrease, and/or combat, and/or prevent growth of microorganisms within the water recirculating device. Further, the cleaning procedure may decrease a risk of cross-contamination between different users. Further, the cleaning procedure may decrease a risk of clogging a filter of the water recirculating device. Consequently, the cleaning procedure may decrease a need of maintenance of the water recirculating device.

In general, the inventive concept contributes to the effectiveness of a water recirculating device in terms of hygiene and reduction of water consumption. This is achieved by identifying an end of a user sequence. Hereby, a cleaning procedure can be performed after the identified end of the user sequence.

FIG. 1 1 illustrates a water recirculating device 1 100 comprising an outlet 1 102 configured to output water, a collecting arrangement 1 104 arranged to collect water output by the outlet, a recirculating path 1 108 in liquid communication with the outlet 1 102 and the collecting arrangement 1 104, a discard path 1 106 configured to discard water from the water recirculating device 1 100, a presence sensor arrangement (not shown) configured to collect presence sensor data and a computing unit (not shown) configured to receive presence sensor data and to identify an end of a user sequence of the water recirculating device 1 100 based on the presence sensor data, and to perform a cleaning procedure of the water recirculating device 1 100.

It is to be understood that the function of the computing unit may be incorporated into any other part of the water recirculating device 1 100. For example, the presence sensor arrangement may be configured to receive and analyze presence sensor data. It may also be possible to analyze data generated by the water recirculating device externally, such as in a cloud network.

The water recirculating device may further comprise an external water path 1 1 10 connected to an external water source. Hereby, external water may be fed to the water recirculating device 1 100. The external water path 1 1 10 may connect to a valve arrangement 1 1 12.

The water recirculating device 1 100 may further comprise a pump

1 1 14 for providing a flow of water in the water recirculating device 1 100.

The water recirculating device 1 100 may further comprise an evacuation path 1 120 configured to allow a flow of water towards the collecting arrangement 1 104. Hereby, the water recirculating device 1 100 may be drained via the evacuation path 1 120 and the discard path 1 106.

The water recirculating device 1 100 may comprise a water treatment arrangement 1 1 16 configured to treat water. The water treatment

arrangement 1 1 16 may comprise a filter arrangement and/or a UV light treatment arrangement.

The water recirculating device 1 100 may comprise a heating

arrangement 1 1 18 configured to heat water passing the heating arrangement 1 1 12.

The water recirculating device 1 100 may comprise a water quality sensor arrangement. The water quality sensor arrangement 1 1 14 may comprise an electrical conductivity sensor and/or a UV-sensor, and/or a turbidity sensor. The water quality sensor arrangement may be configured to collect water quality data of water collected by the collecting arrangement 1 1 14. The water quality sensor arrangement may be arranged in the collecting arrangement 1 104.

The presence sensor arrangement may comprise an infrared sensor, and/or a light receiving element, and/or an array of light receiving elements. The presence sensor arrangement may comprise an electromagnetic radiation receiving sensor. The presence sensor arrangement may comprise a sensor based on capacitive effects. The presence sensor arrangement may comprise an acoustic vibration receiving sensor. The presence sensor arrangement may comprise an accelerometer, and/or a force sensor, and/or a vibration sensor. The accelerometer, and/or a force sensor, and/or a vibration sensor may be placed in or at a supporting surface being in proximity of the water recirculating device 1 100. The supporting surface may be a floor of a shower cabin. The presence sensor arrangement may be placed in a ceiling of a room wherein the water recirculating device 1 100 is placed. The presence sensor arrangement may be placed on or at the supporting surface on which a user is intended to be located when using the water recirculating device 1 100. In one example, the water recirculating device is integrated into a hair wash comprising a seating area, and the presence sensor arrangement comprises an accelerometer and/or a force sensor arranged in the seating area. It is to be understood that the presence sensor arrangement may comprise other types of sensors capable of detecting a movement or presence of a user.

Referring now to FIG. 12a, an example of a water recirculating device 1200a is illustrated. The water recirculating device 1200a comprises a supporting surface, such as a floor, on which a user may stand when using the water recirculating device 1200a. The water recirculating device 1200a may be a water recirculating shower.

Referring now to FIG: 12b, a water recirculating device 1200b is illustrated. The water recirculating device 1200b comprises a seat in which a user may be seated when using the water recirculating device 1200b. The water recirculating device 1200b may be a water recirculating shower configured to be used as a hair wash in a hair salon.

Referring now to FIG. 13a, an example of a water recirculating device 1300a is illustrated comprising a presence sensor arrangement. The presence sensor arrangement here comprises a light receiving element, such as an infrared sensor. The light receiving element is top mounted, and an example of a sensing volume resulting from such an arrangement is shown. Referring now to FIG. 13b, an example of a water recirculating device 1300b is illustrated comprising a presence sensor arrangement. The presence sensor arrangement here comprises a light receiving element, such as an infrared sensor. The light receiving element is side mounted, and an example of a sensing volume resulting from such an arrangement is shown.

Referring now to FIG. 14a-14d, graphs relating to a use of a water recirculating device are illustrated.

FIG. 14a illustrates a flow rate of water exiting an outlet of the water recirculating device over time. A first user sequence 1420 here comprises a first sub-user sequence 1422 and a second sub-user sequence 1424. The first user sequence 1420 relates to a use of the water recirculating device by a first user. The first user sequence 1420 may comprise a start time and an end time. The presence sensor arrangement of the water recirculating device may be configured to determine a user sequence duration 1426 elapsed based on the start and end time. As can be seen in FIG. 14d, the first user sequence 1420 here coincide with the onset and end of water flow.

Still referring to FIG. 14a, the presence sensor arrangement may be configured to determine an intermission duration elapsed from an end of the first sub-user sequence 1422 and/or the second sub-user sequence 1424. A first intermission duration 1428 and a second intermission duration 1430 is indicated in the graph. Based on the intermission duration, an end of the first user sequence 1420 may be identified. As can be seen, the intermission duration does not necessarily connect, i.e. extend for a whole duration between, a sub-user sequence and a subsequent sub-user sequence or user sequence.

With reference to the user sequence duration and the intermission duration, it may be possible to define a pre-determined threshold, and if the user sequence duration and/or the intermission duration exceeds such a threshold, an end of the user sequence may be identified. An example of a user sequence duration threshold may be at least five minutes, such as at least ten minutes, such as at least 15 minutes. An example of an intermission duration threshold may be at least one minute, such as at least two minutes, such as at least five minutes, such as at least ten minutes.

Referring now to FIG. 14b, presence sensor data is illustrated over time. The graph of the presence sensor data indicates a detection of a user of the water recirculating device. Here, it can be seen that a user was detected slightly before and after the first user sequence 1420, and slightly before and after the second use sequence 1426. As is readily appreciated by the person skilled in the art, the detection of a user via the presence sensor data may be used to identify the end of the first use sequence 1420. For example, a timer may start as the presence sensor data switches from indicating a detection of a user to indicating that a user is not detected. If a user is not detected for a pre-determined period of time, the first user sequence 1420 may be identified as ended at the point in time wherein the presence sensor data switched from indicating a detection of a user to indicating that a user is not detected, or at any other point in time.

Referring now to FIG. 14c, water quality data from a water quality sensor arrangement of the water recirculating deice is illustrated over time. The water quality sensor arrangement is configured to collect water quality data of water collected by the collecting arrangement. However, it is to be understood that the water quality sensor arrangement may be configured to collect data from water in other parts of the water recirculating device. Here, a level of a first substance 1432 and a second substance 1434 is illustrated over time. The first and/or second substance 1432, 1434 may indicate that the first use sequence 1420 has ended. Further, a first sub-user sequence 1436 and a second sub-user sequence 1438 may be identified based on the water quality data. For example, the first substance may be a shampoo, and the second substance may be a conditioner. Hereby, when the conditioner is identified by the water quality sensor arrangement, a second sub-user sequence may be identified. Further, when the level of the conditioner has reached a pre-determined level, an end of the first use sequence may be identified.

In general, it is to be understood that the intermission duration, as well as the user sequence duration, may be defined with respect to the presence sensor data, and/or with respect to the flow rate of the water recirculating device as determined by a flow rate sensor of the water recirculating device, and/or with respect to the water quality data, or with respect to any

combination of the same.

Referring now to FIG. 14d, the first and second sub-user sequences 1422, 1424, comprised in the first user sequence 1420, and the second user sequence 1426 are illustrated over time.

The presence sensor data may comprise data generated by a user input actuation triggered via a user interface of the water recirculating device, and/or via a user interface of an external device, such as a smart phone, and an end of a user sequence may be identified based on the user input actuation.

A cleaning procedure referred to in the sections above may comprise at least partly draining the water recirculating device of water via the discard path. The cleaning procedure may comprise heating water in the water recirculating device by a heating arrangement of the water recirculating device. The heated water may be drained, passing e.g. a water treatment arrangement and other parts of the water recirculating device before exiting via the discard path. Hereby, the water recirculating device may be de- contaminated. It may also be possible to introduce a cleaning solution and/or substance into the water recirculating device. This may be achieved by arranging a reservoir of cleaning solution and/or substance in the water recirculating device, and when an end of a user sequence is identified, the cleaning solution and/or substance may be delivered into various parts of the water recirculating device, e.g. the recirculating path, water treatment arrangement, pump, heating arrangement, and/or evacuation path.

Referring now to FIG. 15, a method for identifying an end of a user sequence of a water recirculating device is illustrated in a flow chart. The method comprises a step 1536 of receiving presence sensor data from a presence sensor arrangement of the water recirculating device, a step 1538 of identifying an end of the user sequence based on the presence sensor data, and a step 1540 of performing a cleaning procedure of the water recirculating device.

The inventive concept has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the inventive concept, as defined by the appended patent clauses.

List of reference signs

1 100 Water recirculating device

1 102 Outlet

1 104 Collecting arrangement

1 106 Discard path

1 108 Recirculating path

1 1 10 External water path

1 1 12 Valve arrangement

1 1 14 Pump

1 1 16 Water treatment arrangement

1 1 18 Heating arrangement

1 120 Evacuation path

1200a Water recirculating device

1200b Water recirculating device

1300a Water recirculating device

1300b Water recirculating device

1420 First user sequence

1422 First sub-user sequence

1424 Second sub-user sequence

1426 First user sequence duration

1428 First intermission duration

1430 Second intermission duration

1432 Level of first substance

1434 Level of second substance

1536 Step of receiving presence sensor data

1538 Step of identifying an end of a user sequence

1540 Step of performing a cleaning procedure

CLAUSES

1 . A method for identifying an end of a user sequence of a water recirculating device, the water recirculating device comprising:

an outlet configured to output water;

a collecting arrangement arranged to collect water output by the outlet;

a recirculating path in liquid communication with the outlet and the collecting arrangement; and

a discard path configured to discard water from the water recirculating device;

wherein the method comprises:

receiving presence sensor data from a presence sensor arrangement of the water recirculating device;

identifying the end of the user sequence based on the presence sensor data; and

performing a cleaning procedure of the water recirculating device.

2. The method according to clause 1 , wherein the presence sensor arrangement comprises an infrared sensor.

3. The method according to clause 1 or 2, wherein the presence sensor arrangement comprises an array of light receiving elements.

4. The method according to any one of the preceding clauses, wherein the presence sensor arrangement comprises an accelerometer and/or a force sensor arranged in the water recirculating device.

5. The method according to any one of the preceding clauses, wherein the user sequence comprises a start time and an end time, wherein the presence sensor arrangement is configured to determine a user sequence duration elapsed based on the start and end time, and wherein the step of identifying the end of the user sequence is further based on the user sequence duration. 6. The method according to any one of the preceding clauses, wherein the user sequence comprises at least one sub-user sequence, and wherein the presence sensor arrangement is configured to determine an intermission duration elapsed from an end of the sub-user sequence, and wherein the step of identifying the end of the user sequence is further based on the intermission duration.

7. The method according to any one of the preceding clauses, wherein the presence sensor data comprises data generated by a user input actuation triggered via a user interface of the water recycling device, and wherein the step of identifying the end of the user sequence is further based on the user input actuation.

8. The method according to any one of the preceding clauses, wherein the water recycling device comprises a water quality sensor arrangement configured to collect water quality data of water collected by the collecting arrangement, and wherein the step of identifying the end of the user sequence is further based on the water quality data.

9. The method according to any one of the preceding clauses, wherein the cleaning procedure comprises at least partly draining the water recirculating device of water. 10. The method according to any one of the preceding clauses, wherein the cleaning procedure comprises heating water in the water recirculating device by a heating arrangement of the water recirculating device.

1 1 .A water recirculating device comprising:

an outlet configured to output water;

a collecting arrangement arranged to collect water output by the outlet;

a recirculating path in liquid communication with the outlet and the collecting arrangement;

a discard path configured to discard water from the water recirculating device;

a presence sensor arrangement configured to collect presence sensor data; and

a computing unit configured to receive presence sensor data and to identify an end of a user sequence of the water recirculating device based on the presence sensor data, and to perform a cleaning procedure of the water recirculating device. 12. The device according to clause 1 1 , wherein the water recirculating device is integrated into a hair wash comprising a seating area, and wherein the presence sensor arrangement comprises an accelerometer and/or a force sensor arranged in the seating area.

The device according to clause 1 1 or 12, wherein the water

recirculating device is a water recirculating shower.