WO2019190384A1

WO2019190384A1 - Fluid detector label and fluid detector system comprising at least one such label

Info

Publication number: WO2019190384A1
Application number: PCT/SE2019/050273
Authority: WO
Inventors: Patrik Gerger
Original assignee: Foolproof Ab
Priority date: 2018-03-29
Filing date: 2019-03-26
Publication date: 2019-10-03
Also published as: SE541636C2; SE1850364A1

Abstract

The present invention relates to a fluid detector label for detecting a fluid on a surface, comprising a detector having at least two detection zones, an antenna for transmitting signals from the fluid detector label and receiving signals to the fluid detector label, and a local control unit operatively connected to the detector and the antenna, wherein the detector, antenna and local control unit are arranged on a lower side of a substrate, and wherein the fluid detector label further comprises spacing means for raising the fluid detector label from a surface, said spacing means being arranged on the lower side of the substrate and having a height of 5 mm or less, preferably 1 mm or less. The invention also relates to a fluid detector system comprising at least one such label.

Description

FLUID DETECTOR LABEL AND FLUID DETECTOR SYSTEM COMPRISING AT

LEAST ONE SUCH LABEL

TECHNICAL FIELD

The present invention relates to a fluid detector label for detecting a fluid on a surface, comprising a detector having at least two detection zones, an antenna for transmitting signals from the fluid detector label and receiving signals to the fluid detector label, and a local control unit operatively connected to the detector and the antenna, wherein the detector, antenna and local control unit are arranged on a first side of a substrate. The invention also relates to a fluid detector system and to methods for manufacturing a fluid detector label and detecting fluid by using a fluid detector label.

BACKGROUND

Fluid detectors and moisture detectors for detecting unwanted moisture and fluids are well known within various technical fields. Especially in buildings comprising materials that are sensitive to moisture, it is often required to detect leaks or excess fluids from household appliances and pipes, to prevent water damage in kitchens and other appliance containing spaces. As modem buildings contain an increasing number of appliances using water, such as dishwashers, ovens, washing machines and refrigerators, the risks for water damage and the costs associated therewith are currently increasing rapidly. In order to minimize costs, it is essential that any leakage is discovered immediately.

A number of different technical solutions can be applied to solve this problem, generally relying on a detection device where the presence of moisture causes the generation of an alarm signal, for instance by closing a circuit.

A problem commonly associated with the known fluid detectors is that they are complex with many components, making them expensive to manufacture, and that they require maintenance in the form of battery changes and controls in order to function reliably over long periods of time. For the end user, a home owner needing a number of fluid detectors in various rooms of a house, such maintenance will require regular checks and may result in fluid leaks going undetected if the checks are forgotten.

Some fluid detectors avoid these problems by relying on a simplified detection where a substance is subjected to a fluid and therethrough changes its physical or chemical properties, resulting in the closure of an electrical circuit and the generation of an alarm signal. These fluid detectors generally suffer the drawback that large quantities of fluid is often needed in order to affect the substance, and that it is difficult to control the reaction time, i.e. the time between the leakage of fluid and the generation of the alarm signal. They are also often not re- usable and need to be replaced after detecting a fluid.

Fluid detectors are previously known from EP2988122, EP3264383 and WO2017/024281, among others. There is therefore clearly a need for an improved fluid detector that is cost effective, small, thin and flexible, making it easy to place in tight spaces while also providing reliable fluid detection over long periods of time without requiring maintenance.

SUMMARY OF THE INVENTION

The object of the present invention is to eliminate or at least to minimize the problems mentioned above. This is achieved through a detector, a detector system and a method for detecting a fluid according to the appended independent claims.

The present invention has a number of benefits and advantages due to its configuration and operation. It is possible to detect not only the presence of a fluid, but also the specific amount of fluid present by the arrangement of the detection zones and the height of the fluid detector label that enables even a single drop of water to contact one of the detection zones and generate a detection signal. Thus, each of the detection zones is arranged to transmit a detection signal to a local control unit when contacted by a fluid, and the local control unit is configured to receive at least one detection signal from a corresponding at least one detection zone, generate an alarm signal based on the at least one received detection signal and send the alarm signal to the antenna,

It is also possible to continuously determine an amount of moisture at the detector and to store and/or transmit data relating to the moisture over time to a local control unit on the detector or to a central control unit, which may be located at a remote location, thereby enabling further analysis on the data and to determine trends and changes over time.

It is highly advantageous if the detector is realized as components on a flexible substrate such as paper or a polymer sheet. The components are preferably printed or applied through dry phase patterning, and an adhesive may be provided on a bottom of the substrate to allow for easy mounting on a surface.

According to one aspect of the invention, an antenna of a detector is provided on a substrate and extends at an angle from said substrate. Thereby, signals can be transmitted in an especially advantageous way, compared to an antenna that lies flush with the substrate.

The spacing means can be separate structures or can be integrated with one or more components on the substrate, such as the detection zones, local control unit, antenna, and/or power source. Alternatively, the spacing means can be one of those components itself.

Through the height of the spacing means a raising of the fluid detector label from a surface is enabled, and by limiting the height to 5 mm or less, preferably 1 mm or less it is achieved that even a single drop of fluid having a volume of 0.05 ml or less is efficiently spread along the detection zone or detection zones by means of wetting and is able to generate detection signals corresponding to the quantity of fluid present.

The local control unit is preferably arranged to generate different alarm signals depending on the number of detection signals received from the detection zones and the number of detection zones present on the fluid detector label. In one aspect of the present invention, the local control unit is arranged to generate a first level alarm signal in response to a detection signal from only one of the detection zones. In one embodiment, the detector comprises at least three detection zones and the local control unit is arranged to generate a second level alarm signal in response to a detection signal from at least two but not more than N detection zones, where N is a predetermined threshold value greater than or equal to two and lower than the total number of detection zones on the fluid detector label.

Preferably, the local control unit is also arranged to generate a third level alarm signal in response to a detection signal from a number of detection zones greater than N.

Thereby an alarm signal directly corresponding to the amount of fluid present at the detector label can be created and different alarm responses produced depending on the need for action to prevent further damage and to alert a user to the leak.

According to one aspect of the invention, the detection zones are arranged as open circuits that are closed by current transmission through the fluid and preferably at least one of the detection zones comprises an open circuit that can be closed by being contacted by 0.05 ml or less of a fluid. Thereby, even a single drop of fluid will generate a detection signal.

According to another aspect of the invention, the label further comprises a temperature sensor for detecting a temperature, wherein the local control unit is configured to control the operation of the temperature sensor and to receive input from said temperature sensor, and wherein preferably the local control unit is further configured to determine a risk for fire and/or freezing depending on a temperature detected by the temperature sensor. Thereby the label or a system to which it is connected can also monitor changes in temperature and generate an alarm if there is a danger of damage due to fire or freezing, serving to further decrease the risk of damages to the place where the label is placed.

According to one aspect of the invention, the fluid detector label forms part of a fluid detection system having a central control unit for receiving signals from the at least one fluid detector label and for generating at least one alarm response based on a received alarm signal. The alarm response preferably comprises operating a valve for turning off a water supply, and the system preferably also comprises input means and/or output means for communicating with a user of the system. Thereby, further damage due to a leak continuing to supply water to the area where the fluid detector label is placed can be avoided, and the system can also receive instructions and deliver status information or other information regarding the system to the user, either directly on site or remotely via internet, an app or similar.

According to the invention, a method for manufacturing a fluid detector label is also provided, comprising the following steps:

providing a substrate

applying a detector having at least two detection zones, an antenna and a local control unit operatively connected to the detector and the antenna on a first side of the substrate, applying spacing means having a height of 5 mm or less, preferably 1 mm or less, to the first side of the substrate. Thereby the label can be manufactured having all the components arranged on the substrate, thus creating a thin and flexible label that can be cost efficiently produced and comprise all components required to detect a quantity of fluid. Preferably, the label is manufactured through dry phase patterning, but other methods such as printing could also be used, or alternatively the components could be applied through the use of an electrically conductive adhesive in order to attach each component on the surface of the substrate.

According to the invention, a method for detecting the presence of a fluid is also provided, the method comprising the steps of:

providing a fluid detection label having a substrate with a plurality of detection zones on a first side, said detection zones each being able to generate a detection signal in response to a fluid,

receiving at least one detection signal in a local control unit operatively connected to the detection zones,

generating an alarm signal depending on the number of received detection signals in relation to a number of detection zones and transmitting said alarm signal from the fluid detection label.

Preferably, a first level alarm signal is generated if only one detection signal is received by the local control unit. Thereby a small quantity of fluid, generally 0.05 ml or less, is detected.

Preferably, a second level alarm signal is generated if detection signals are received from two or more detection zones but not more than N detection zones, where N is a predetermined threshold value greater than or equal to two and lower than the total number of detection zones on the fluid detector label. Thereby a larger quantity of fluid is detected, but it is also reflected in the second level alarm signal that the larger quantity is not sufficient to cover the entire surface of the fluid detector label.

Preferably, a third level alarm signal is generated if detection signals are received a number of detection zones greater than N. Thereby a large quantity of fluid is detected, sufficient to cover all detection zones and significant of a large leak that would require immediate action in order to prevent damages to the area where the label is placed.

In an alarm response to the first, second and third level alarm signals, the system chooses an appropriate action to suit the situation. If smaller quantities of fluid are detected it may be sufficient to alert a user through a user interface or to generate a visual alarm or a sound alarm, but if larger quantities of fluid are detected a more forceful response can instead be selected, such as the switching off of a water supply to the area where the label is placed along with an alarm signal to the user.

Many additional benefits and advantages of the invention will become readily apparent to the person skilled in the art in view of the detailed description below.

DRAWINGS The invention will now be described in more detail with reference to the appended drawings, wherein

Fig. 1 discloses a schematic view from below of a fluid detector label according to a preferred embodiment of the present invention;

Fig. 2 discloses a schematic view from below of the fluid detector label of Fig. 1 in a state where one detection zone is contacted by a fluid;

Fig. 3 discloses a schematic view from below of the fluid detector label of Fig. 1 in a state where two detection zones are contacted by a fluid;

Fig. 4 discloses a schematic view from below of the fluid detector label of Fig. 1 in a state where all detection zones are contacted by a fluid;

Fig. 5 discloses a cross-sectional view from the side of the fluid detector label of Fig. 1 placed above a surface;

Fig. 6 discloses a schematic view of a fluid detector system according to the present invention, comprising a fluid detector label according to the preferred embodiment of Fig. 1;

Fig. 7 discloses a schematic view of the system of Fig. 6 with a plurality of fluid

detector labels;

Fig. 8 discloses a schematic view of a fluid detector label according to the invention with adjustable antennas;

Fig. 9a-9c discloses schematic views of the antenna of Fig. 9 in an elevated state in views from different sides of the substrate; and

Fig. 10 discloses schematically the steps of the manufacturing method according to the present invention for manufacturing a fluid detector label.

Fig. 11 discloses steps of a detection method according to the present invention;

Fig. 12 dicloses a schematic side view of an alternative embodiment of the invention;

and

Fig. 13 discloses adhesion between a drop of fluid and a fluid detector label according to the present invention.

DETAILED DESCRIPTION

Fig. 1 discloses a fluid detector label 10 according to a preferred embodiment of the present invention, having a substrate 4 on which a plurality of components are arranged. The components comprise a local control unit 2, an antenna 3 and a detector 1 having at least two and in this embodiment four detection zones la, lb, lc, ld. The components are operatively connected to each other so that signals can be transmitted from the detection zones la, lb, lc, ld to the local control unit 2 and from the local control unit 2 to the antenna 3 and vice versa. Preferably a power source 5 is also provided to power the components, in this embodiment in the form of a battery 5 that is also arranged on the substrate 4. The components are arranged on a first side of the substrate 4, the first side being the side that is facing towards a surface on which fluid detection is to be performed, when the fluid detector label 10 is in use. In other words, when the fluid detector label 10 is in use, it is placed with the components facing towards the surface. In a non-limiting example, the surface is a floor, or another horizontal surface, whereby the first surface of the fluid detector label may be referred to as the lower surface. An adhesive may also be provided on at least a part of the substrate 4 or components so that the fluid detector label 10 can be attached to the surface.

Also provided are spacing means 6 that may be part of any of the components mentioned above or that may alternatively be at least one separate component on the substrate 4, which will be described in more detail further below with reference to Fig. 5.

The detection zones la, lb, lc, ld are in this embodiment open circuits that are arranged on different parts of the substrate 4, so that a power differential is constantly provided but no current can flow through the circuit. If a conductive fluid such as water should contact the open circuit, a current will start to flow through the circuit and by each of the circuits being connected to the local control unit 2, that current would be detected in the form of a signal to the local control unit 2 that a fluid is present in a specific detection zone la, lb, lc, ld. By determining in which detection zones la, lb, lc, ld the current flows, the local control unit 2 will be able to determine the amount of fluid present at the fluid detector label 10, determine an alarm level from a predetermined selection of alarm levels based on the determined amount of fluid present, and to produce or generate an alarm signal in response to the determined alarm level, and transmit the alarm signal via the antenna 3.

The detection of different amounts of fluid and corresponding generation of different alarm signals will now be described in more detail with reference to Figs. 2-4. In the non-limiting example of Figs. 2-4 three different alarm levels are used, corresponding to three different amounts of fluid. It is to be noted that representing the detection zones la, lb, lc, ld as open circuits that detects the presence of a fluid through noting the flow of current through each circuit is only one preferred way of fluid detection. Alternative ways include providing detection zones where inductive changes signify the presence of a fluid and other ways may also be used within the scope of the present invention.

In Fig. 2, a small amount of fluid F is present in one detection zone lc. The rest of the fluid detector label 10 remains dry. The fluid F allows a current to flow in the open circuit of the detection one lc, and thereby the detection zone lc generates a detection signal to the local control unit 2, said current being supplied by the power supply 5. The detection signal can be in the form of a change in current, voltage or resistance in the detection zone lc.

In response to receiving only one detection signal from a detection zone lc, the local control unit 2 determines that the alarm level is the first alarm level, from the selection of three alarm levels, generates a first level alarm signal and transmits the first level alarm signal via the antenna 3 to a central control unit 100. The central control unit 100 may be part of a fluid detector system that will be further discussed below with reference to Fig. 6.

In Fig. 3, a larger amount F is present in two of the detection zones lb, lc. In each of these zones lb, lc, a detection signal is generated as described above and transmitted to the local control unit 2. In response to receiving detection signals from more than one but not all of the detection zones la, lb, lc, ld, the alarm level is determined as the second level, and a second level alarm signal is generated by the local control unit 2 and transmitted via the antenna 3 to the central local control unit 100. More generally, the local control unit 2 may be configured to determine the alarm level to the second level in response to receiving signals from more than one but not more than N detection zones, where N is a predetermined threshold value greater than or equal to two and lower than the total number of detection zones la, lb, lc, ld on the fluid detector label 10.

In Fig. 4, an even larger amount F is present across the entire detector label 10 and thereby generates detection signals in each of the detection zones la, lb, lc, ld. Receiving these signals causes the local control unit 2 to determine the alarm level as the third level, and to generate a third level alarm signal that is transmitted to the central local control unit 100.

More generally, the local control unit 2 may be configured to determine the alarm level to the third level in response to receiving signals from a number of detection zones equal to or greater than N.

Of course, additional alarm levels and corresponding alarm level signals may be added if suitable, and additional threshold values may be used for determining the relevant alarm level.

The local control unit 2 is configured to select the first, second and third level alarm signals depending on the number of detection zones la, lb, lc, ld on the fluid detector label 10 and on the number of zones la, lb, lc, ld where a fluid F is detected. Thus, in a fluid detector label with only two detection zones la, lb, if the local control unit 2 receives a detector signal from one of them the first level alarm signal will be generated whereas a receiving of two detector signals would instead generate the third level alarm signal since this is the maximum amount of fluid F that can be detected by that label. In another fluid detector label 10 a larger number of fluid detection zones could instead be provided, so that the second level alarm signal can be generated where detector signals are received from a plurality of fluid detection zones but where not all fluid detection zones are exposed to the fluid.

Of course, the embodiments described herein would be equally applicable if there is provided a different number of detection zones than what is illustrated in the example of Figs. 2-4, or a different number of alternative alarm signals than the three described above.

It is also advantageous if the local control unit 2 is configured to select the alarm signal depending simply on the number of detection signals received in relation to the total number of detection zones provided on the fluid detector label, but in another embodiment it could also be advantageous to determine whether the detection zones that are transmitting detector signals are adjacent or in different parts of the fluid detector label, since the presence of fluid in multiple areas of the fluid detector label could signify a larger quantity of water or possibly even that there is a fault in some of the detection zones that make them unable to generate the detector signal.

Fig. 5 discloses the fluid detector label 10 from the side, showing the components as described above and also showing the spacing means 6 as a different component. As also stated above, it is to be noted that the spacing means 6 could also be integrated with any or all of the components mentioned above, as long as a height h of the spacing means 6 is suitable. Thus, if any of the components is already of a suitable height, that component could serve as the spacing means 6 and thereby avoid the need for additional spacing means 6 added to the fluid detector label 10. The separate spacing means 6 shown in Fig. 5 could be of any suitable material, such as a polymer material or a metal, and could be applied at any stage during manufacture. The height h is less than 5 mm, preferably less than 1 mm, and it is preferable that the height h is equal to or less than the height of a drop of fluid. Thereby, the presence of a drop of fluid having a volume of as little as 0.05 ml that contacts the fluid detector label 10 will allow that fluid to be introduced under the fluid detector label 10 and be spread and wet in a suitable way across the first side 11 of the label 10 in order to contact the fluid detection zones la, lb, lc, ld in an efficient way. The spreading along the first side 11 takes place through adhesion between the fluid and the first side 11 of the fluid detector label and preferably also a second surface 20 on which the fluid detector label 10 rests. It is

advantageous to use a substrate 4 made from a material that is essentially unaffected by exposure to fluid, such as PET, PP, PE, vinyl, or a metal, so that the fluid will not be able to penetrate into the material and prevent a re-use of the label 10. Especially preferred is to use PET (polyethylene terephtalate) which is a stable and durable material well suited for this purpose.

Also disclosed by the figure is a second surface 20, which may in some examples be a floor, on which the fluid detector label 10 can be placed and a small quantity of fluid F that contacts one of the fluid detection zones la. In the figure, the label 10 is shown slightly above the second surface 20 in order to clearly show the components from the side, but it is to be noted that the fluid detector label 10 would in use be placed directly on the second surface 20 so that the spacing means 6 elevate the substrate 4 with the components to a suitable height.

With reference to Fig. 13, it will now be explained how the invention is able to benefit from the properties of a fluid such as water in order to improve the fluid detection

Fig. 13 discloses the fluid detector label 10 placed on the height h above a second surface 20 such as a floor. The height h is achieved through spacing means 6 as described herein. Due to the arrangement of the fluid detector label 10 at a height h that is smaller than the height of a drop of water F, adhesion to the first surface 11 and optionally also to the second surface 20 transports and spreads the drop F in the direction of the horizontal arrow H so that the drop F is able to wet the first surface 11 and preferably also the second surface 20, thereby spread out to cover the first surface 11. By adapting the height h, the spreading of the fluid due to wetting along the first surface 11 can be controlled so that one drop activates one detection zone la, lb, lc, ld and larger quantities activates a larger number of detection zones, as desired. In a drop of water, there is cohesion between molecules that leads to the formation and maintenance of a spherical shape and creates a surface tension. When contacting a solid surface, however, adhesion between the solid material and the liquid will lead to the liquid wetting the surface if the adhesion is larger than the cohesion within the drop of water. For the present invention, the drop of water is drawn into a gap between the fluid detector label 10 and the second surface 20 upon which it rests.

The magnitude of adhesion depends on properties of the solid material as well as on the dimensions of the gap where a smaller gap will give a significantly larger adhesive force than a larger gap. Therefore, it is highly advantageous that the height h is 5 mm or smaller, preferably about 1 mm, in order to achieve a suitable adhesion between the label 10 and the fluid F. Selecting the material for the substrate 4 of the label 10 will also increase the adhesion, where polar materials such as PET enables a higher surface adhesion. Polar ester groups in PET (ethylene terephthalate) hold the polyester into strong crystals.

Water wets most building materials, including ceramics such as brick, stone and concrete, wood, metals and some plastics. If second surface 20 is a floor the adhesion will increase if the floor is made of such building materials.

For further information regarding the properties of fluids such as water, we refer to“Materials in Construction: An Introduction”, 3rd Edition, by G.D. Taylor.

Figs. 6-7 disclose the fluid detector system 1000 with a fluid detector label 10 as described above, and also comprising passive components 7 such as humidity sensor and temperature sensors, if suitable (see below). The fluid detector label 10 communicates with the central control unit 100 via the antenna 3 and is able to both transmit and receive signals. If a power supply 5 is provided on the fluid detector label 10, the local control unit 2 can be configured to transmit a status signal at regular intervals to the central control unit 100, to show that the fluid detector label 10 is active and functioning. If no power supply 5 is present on the fluid detector label 10, the central control unit 100 can instead transmit signals to the fluid detector label 10 as desired in order to check a status of the fluid detector label 10.

The central control unit 100 communicates with at least one but preferably a plurality of fluid detector labels 10 according to the present invention. By receiving regular status signals from each fluid control label, the central control unit 100 can monitor the labels and determine if any of them is malfunctioning or needs service or replacement, and of course also to determine that no fluid has been detected at any of the fluid detector labels. If an alarm signal is received from one or more of the fluid detector labels, the central control unit 100 generates an alarm response depending on if the alarm signal is a first, second or third level alarm signal as described above, and also depending on if alarm signals are received from only one or from multiple fluid detector labels 10. The alarm responses include generating an alarm signal that can be in the form of light, sound or notification to a user, for instance, and the alarm responses also include actions that prevent further damage to an area where the fluid detector labels 10 are placed such as the operating of a shut-off valve 130 to turn off a water supply to a room or a building where a leak has occurred. The system 1000 also preferably comprises input means 121 and output means 122 that form an interface 120 through which the central control unit 100 can communicate with a user. The interface 120 may comprise a display, a keyboard, a mouse or joystick, a touchscreen, an app for a smartphone or tablet, or any other suitable means for communication. The central control unit 100 may also communicate through a router 110 with remote units that can be reached through an internet connection.

In some embodiments, the fluid detector label 10 may also include additional sensors such as a temperature sensor or a moisture sensor that are arranged as components on the substrate 4 and communicate with the local control unit 2, preferably included among the passive components 7. A moisture sensor can detect a moisture in the air surrounding the fluid detector label 10 and the local control unit 2 can be configured to generate alarm signals also if the moisture content is above a predetermined threshold even if no fluid as such has been detected. Also, a temperature sensor can detect a temperature at the fluid detector label 10 and the local control unit 2 can be configured to transmit signals to the central control unit 100 that inform of the temperature at a specific time or over longer time periods such as a maximum or a minimum value for a predetermined time interval or the time elapsed since the last status signal was sent. Also, the local control unit 2 or the central control unit 100 can determine a risk of freezing or of fire in response to temperature data and can monitor the state of the fluid detector labels 10 and/or communicate with the user in response thereto.

Fig. 8 discloses an alternative embodiment of the fluid detector label 10 in a view from above with the antenna 3 provided on flaps 31 protruding from the substrate 4. The flaps 31 can be made from the same material as the substrate 4 but can also be made from another material if desired. Apart from the design of the antennas 3 the fluid detector label 10 according to this embodiment is similar to the preferred embodiment above, and it is to be noted that the alternative antenna design could also be incorporated into the preferred embodiment above or be combined with any of the other embodiments described herein. In order to increase a range of the antenna, the substrate and the antenna can be creased or punched through in order to facilitate an elevation of the antenna.

Fig. 9a is a view from one side of the substrate 4 with the flaps 31 being folded upwards so that the antenna 3 extends at an angle a from the substrate, said angle a preferably being in the range of 45-135 degrees from a position with the flap extending away from the substrate 4 and in the same plane as the substrate 4. The angle a is preferably adjustable, so that the orientation of the flap 31 can be altered depending on what is suitable at a given time.

Thanks to the antenna 3 being adjustable in this way, the transmission range of the fluid detector label 10 can be considerably increased. In this embodiment, the flaps 31 are folded upwards as shown by Fig. 9b and Fig. 9c where two different arrangements of the flaps 31 can be seen. If the fluid detector label 10 is placed in a location where transmission is difficult, such as directly underneath a large metal structure such as a dishwasher, this adjusting of the antenna 3 can significantly improve both the transmission range and the lifetime of the power source 5. Preferably, an adhesive is provided on at least a part of the flaps 31 so that the flaps 31 can be attached to each other to form an arc or any of the flaps 31 can alternatively be attached to a structure such as a wall to fixate it in an elevated position. Alternatively, the flaps 31 can be mechanically joined to each other. Fig. 12 discloses an alternative embodiment of the invention, where the fluid detector label 10 can be pivoted upwards from the second surface 20. In this embodiment, the fluid detector label 10 is mounted on the second surface 20 by means of an adhesive 13 applied to at least one portion of the fluid detector label 10, and the fluid detector label 10 can be pivoted around a joint 41 in the substrate 4 or by the substrate 4 itself being flexible enough to allow such a motion without disrupting the components or their connections to each other. The purpose of pivoting the fluid detector label 10 is to enable cleaning after a fluid F has been detected, so that the fluid detector label 10 and the second surface 20 can be wiped down or otherwise dried or cleaned.

The antenna 3 is preferably arranged to extend at an angle from the substrate in each of the embodiments described herein, and the angle may be adjustable as desired. This is achieved by a part of the substrate 4 having the antenna 3 arranged thereon may be bendable in relation to the rest of the substrate 4. For instance, the substrate 4 may be perforated along one side of the antenna 3 but not on another side so that the part of the substrate 4 carrying the antenna 3 may be released along that line and bent away from a remainder of the substrate 4 while still being attached thereto along at least one other side of the antenna. In other embodiments, the antenna 3 may be applied to a portion of the substrate 4 that extends away from other parts of the substrate 4, such as the flaps 31 exemplify. Alternatively, the antenna 3 could be applied to a flap that extends in any other direction from the substrate 4 or that forms part of the substrate 4 but is cut away from other parts of the substrate 4 along one or more sides of the antenna 3. The effect of arranging the antenna 3 in this way is that the antenna 3 itself and the portion of substrate 4 on which it is arranged may be adjusted in relation to the fluid detector label so that the antenna 3 extends in any desired direction from the fluid detector label.

A preferred method of manufacturing the fluid detector label 10 will now be described in more detail with reference to Fig. 10.

The fluid detector label 10 is manufactured in three phases. In a first phase A (dry patterning phase), a material supply Al is arranged in the form of a foil or film on a roll. This foil or film is the substrate 4 and it is a flexible yet durable material.

The web of the substrate material is contacted by a cliche A2 with a desired pattern and a milling wheel A3 that cuts away the pattern given by the cliche A2. In this way, the substrate material is cut to form the pattern (conductive paths) that will generate the antenna and the detection zones (both included in the conductive paths) that are adapted to make electrical connection between the components and the conductive paths.

In a second phase B, a conductive adhesive Bl is applied to the web and components included with the power source B2 are applied to the substrate 4 and mounted on the first surface of the substrate by means of the adhesive. Depending on the adhesive used, a curing step B3 may be performed before a protective layer B4 is applied to the web of the substrate 4. Finally, a die cutter B5 cuts the web to separate the individual fluid detector labels 10 from each other.

In a third phase C, the fluid detector labels are packed and ready for use. The following is a non-limiting description of the components and materials suitable for use in the fluid detector label 10.

Substrate is preferably a paper, polymeric or metallic material, or a combination of these. Polymeric materials can be PET, PP, PE or vinyl. The substrate material should

advantageously have a low critical surface tension, preferably below 100 mN/m, more preferably below 75 mN/m. The critical surface tension of some of the suitable mentioned materials are 43 mN/m for PET and 31 mN/m for PP and PE. Thereby, the spreading of fluid on the surface of the fluid detector label 10 and activation of the detection zones is improved.

The adhesive is preferably an electrically conductive adhesive such as Henkel's Hysol

ECCOBOND CE 3103WLV, but can alternatively be a conductive tape, glue or resin.

Wiring for the detection zones and connections between components is preferably made from a metal such as aluminium or copper or by an alloy, but materials such as graphene can alternatively also be used.

The local control unit is preferably a chip, microcontroller or ASIC.

Power source is preferably a printed battery or a cell coin.

The antenna is preferably made from aluminium oxide, aluminium, copper, or a combination thereof.

Passive components may include a temperature sensor in the form of a resistive thermometer, temperature measuring chip, or a thermistor.

Alternatively, the fluid detector label can also include a Flex PCB/Flex Rigid that can be integrated with the components or replace one or more of them.

The finished fluid detector labels 10 are preferably dimensioned depending on the height h on which they are to be arranged above a surface. For a height h of 1.0 mm, the fluid detector label 10 is preferably 25 x 25 mm or larger. Due to the adhesion between the fluid detector label 10 and the fluid/water, one drop (i.e. 0.05 ml) would in this case spread over 8 mm diameter of the fluid detector label 10, whereas five drops (i.e. 0.25 ml) would spread over 18 mm and ten drops 8 (i.e. 0.5 ml) would spread over 25 mm. This would in such an

embodiment form the three alarm levels.

For other heights h, the dimensions of the detection zones and the fluid detector label 10 as a whole would of course need to be adapted, as will be readily understood by the skilled person.

The finished fluid detector label 10 can be active, i.e. having a battery 5 that supplies power to the components of the fluid detector label 10. In such an embodiment, the transmission range of the label can be up to 100 m and the fluid detector label would send an identification signal and a status signal at predetermined intervals, such as once per day.

In another embodiment, the fluid detector label 10 can be a passive label without a battery. This provides a more cost efficient label and avoids the problems of the battery running out of power. In such an embodiment, the central control unit may use a backscattering technique to read the status of the fluid detector label 10 at suitable intervals.

In yet another embodiment, the fluid detector label 10 can be Battery Assisted Passive (BAP) where a battery is combined with energy transmitted to the label when the central control unit reads the status of the fluid detector. This enables a range of about 30 m, compared with 6-8 m for the passive label.

Turning now to Fig. 11, there is illustrated a method for detecting the presence of a fluid using a fluid detection label. The fluid detection label used in the method corresponds to a fluid detection label according to any of the embodiments presented herein, at least having a substrate with a fluid detector, an antenna and a local control unit on a first side, wherein the local control unit is operatively connected to the fluid detector and the antenna, and wherein the fluid detector comprises a plurality of detection zones, said detection zones each being configured to generate a detection signal in response to a fluid.

In one or more embodiments, the method of Fig. 11 comprises:

In step 1100: generating at least one detection signal, by a respective at least one detection zone.

As described herein, the detection zones may be arranged as open circuits that are closed by current transmission through the fluid, and wherein preferably at least one of the detection zones comprises an open circuit that can be closed by being contacted by 0.05 ml or less of a fluid. Generating a detection signal, by a detection zone, may in these embodiments comprise generating a detection signal in response to the circuit of the detection zone being closed, thereby indicating contact with a fluid.

In step 1110: receiving, in the local control unit, the generated at least one detection signal.

In step 1120: generating, by the local control unit, an alarm signal depending on the number of received detection signals in relation to a total number of detection zones. In one embodiment, the local control unit can send alarm signals repeatedly as long as detection signals are received by the local control unit, but in another embodiment alarm signals corresponding to detection signals from only one or two detection zones can be sent as a response to the central control unit reading the label 10 at predetermined interval, whereas an alarm signal corresponding to the highest level would instantaneously be sent without waiting for a reading signal from the central control unit.

Step 1120 may comprise generating any of the first, second or third level alarm signal according to any of the embodiments and dependent of any of the conditions described in connection with Figs. 2 to 4.

For example, step 1120 may comprise, generating a first level alarm signal if only one detection signal is received by the local control unit; generating a second level alarm signal if detection signals are received from two or more detection zones but not more than N detection zones; and generating a third level alarm signal if detection signals are received from a number of detection zones greater than N.

In step 1130: transmitting the alarm signal from the fluid detection label to a central control unit.

Transmission, or communication, of the alarm signal from the fluid detection label to the central control unit may be done via any suitable wired or wireless network technology known in the art.

In some embodiments, the method may further comprise:

In an optional step 1140: receiving, in the central control unit, an alarm signal from the local control unit of at least one fluid detection label.

In an optional step 1150: generate, by the central control unit, an alarm response, in response to the received alarm signal.

As described herein, when an alarm signal is received from one or more of the fluid detector labels the central control unit 100 may generate different alarm responses depending on if the alarm signal is a first, second or third level alarm signal. The alarm response generated also depends on if alarm signals are received from only one or from multiple fluid detector labels.

In different embodiments, generating the alarm response may include generating an alarm signal that can be in the form of for instance light, sound or notification to a user; trigger actions that prevent further damage to an area where the fluid detector labels are placed, such as the operating of a shut-off valve to turn off a water supply to a room or a building where a leak has occurred; or both.

Although embodiments of the invention described above with reference to Fig. 11 comprise a local control unit and a central control unit, and processes performed in at least one processor, the invention also extends to computer programs, particularly computer programs on or in a carrier, adapted for putting the invention into practice. The programs may be in the form of source code, object code, a code intermediate source and object code such as in partially compiled form, comprise software or firmware, or in any other form suitable for use in the implementation of the process according to the invention. The program may either be a part of an operating system, or be a separate application. The carrier may be any entity or device capable of carrying the program. For example, the carrier may comprise a storage medium, such as a Flash memory, a ROM (Read Only Memory), for example a DVD (Digital

Video/Versatile Disk), a CD (Compact Disc) or a semiconductor ROM, an EPROM (Erasable Programmable Read-Only Memory), an EEPROM (Electrically Erasable Programmable Read-only Memory), or a magnetic recording medium, for example a floppy disc or hard disc. Further, the carrier may be a transmissible carrier such as an electrical or optical signal which may be conveyed via electrical or optical cable or by radio or by other means. When the program is embodied in a signal which may be conveyed directly by a cable or other device or means, the carrier may be constituted by such cable or device or means. Alternatively, the carrier may be an integrated circuit in which the program is embedded, the integrated circuit being adapted for performing, or for use in the performance of, the relevant processes.

In one or more embodiments, there may be provided a computer program loadable into a memory communicatively connected or coupled to at least one data processor, e.g. the local control unit 2 or the central control unit 100, comprising software or hardware for executing the method according any of the embodiments herein when the program is run on the at least one data processor.

In one or more further embodiment, there may be provided a processor-readable medium, having a program recorded thereon, where the program is to make at least one data processor, e.g. the local control unit 2 or the central control unit 100, execute the method according to of any of the embodiments herein when the program is loaded into the at least one data processor.

The invention is not to be seen as limited by the specific embodiments described above but rather by the scope of the appended claims. In particular, it is to be noted that features from one embodiment may freely be combined with other embodiments, unless such a combination would be unsuitable to the skilled person.

Claims

1. Fluid detector label (10) for detecting a fluid on a surface, comprising

a fluid detector (1) having at least two detection zones (la, lb, lc, ld), an antenna (3) configured to transmit signals from the fluid detector label (10) and receive signals to the fluid detector label (10), and

a local control unit (2) operatively connected to the detector and the antenna

(3),

wherein each of the detection zones (la, lb, lc, ld) is arranged to transmit a detection signal to the local control unit (2) when contacted by a fluid,

wherein the local control unit (2) is configured to: receive at least one detection signal from a corresponding at least one detection zone; generate an alarm signal based on the at least one received detection signal; and send the alarm signal to the antenna (3), wherein the detector, antenna (3) and local control unit (2) are arranged on a first side of a substrate (4), the first side being the side that is facing towards the surface when the fluid detector label (10) is in use, and

wherein the fluid detector label (10) further comprises spacing means (6) for raising the fluid detector label (10) from a surface, said spacing means (6) being arranged on the first side of the substrate (4) and having a height of 5 mm or less, preferably 1 mm or less.

2. Fluid detector label (10) according to claim 1, wherein the spacing means (6) are a separate structure arranged on the substrate (4) or protrusions from the substrate (4).

3. Fluid detector label (10) according to claim 1, wherein the spacing means (6) are integrated with at least one component arranged on the substrate (4).

4. Fluid detector label (10) according to any previous claim, wherein the local control unit (2) is further configured to determine an alarm level based on the received at least one detection signal, and to further generate the alarm signal based on the alarm level.

5. Fluid detector label (10) according to claim 4, wherein the local control unit (2) is arranged to generate a first level alarm signal in response to a detection signal from only one of the detection zones (la, lb, lc, ld).

6. Fluid detector label (10) according to claim 4 or 5, wherein the detector comprises at least three detection zones (la, lb, lc, ld) and the local control unit (2) is arranged to generate a second level alarm signal in response to a detection signal from at least two but not more than N detection zones (la, lb, lc, ld), where N is a predetermined threshold value greater than or equal to two and lower than the total number of detection zones (la, lb, lc, ld) on the fluid detector label (10).

7. Fluid detector label (10) according to any of the claims 4 to 6, wherein the local

control unit (2) is arranged to generate a third level alarm signal in response to a detection signal from a number of detection zones (la, lb, lc, ld) greater than N, where N is a predetermined threshold value greater than or equal to two and lower than the total number of detection zones (la, lb, lc, ld) on the fluid detector label (10).

8. Fluid detector label (10) according to any previous claim, further comprising a power source (5) arranged on the substrate (4) for supplying power to the detector, the local control unit (2) and the antenna (3).

9. Fluid detector label (10) according to any previous claim, wherein the detection zones (la, lb, lc, ld) are arranged as open circuits that are closed by current transmission through the fluid, and wherein preferably at least one of the detection zones (la, lb, lc, ld) comprises an open circuit that can be closed by being contacted by 0.05 ml or less of a fluid.

10. Fluid detector label (10) according to any previous claim, further comprising a

temperature sensor for detecting a temperature, wherein the local control unit (2) is configured to control the operation of the temperature sensor and to receive input from said temperature sensor, and wherein preferably the local control unit (2) is further configured to determine a risk for fire and/or freezing depending on a temperature detected by the temperature sensor.

11. Fluid detector label (10) according to any previous claim, wherein the antenna (3) is arranged to extend at an angle from the substrate (4), said angle preferably being adjustable.

12. Fluid detector label (10) according to any previous claim, wherein the substrate (4) comprises a material having a critical surface tension of 100 mN/m or less, preferably 75 mN/m or less.

13. Fluid detector system comprising at least one fluid detector label (10) according to any previous claim, and further comprising a central control unit (100) configured to receive signals from the at least one fluid detector label (10) and to generate at least one alarm response based on a received alarm signal.

14. Fluid detector system according to claim 13, wherein the system comprises a valve and the alarm response comprises operating the valve for turning off a water supply, and wherein the system preferably also comprises input means and/or output means for communicating with a user of the system.

15. Method for manufacturing a fluid detector label (10), comprising the following steps: providing a substrate (4),

cutting a pattern in said substrate (4),

applying in said pattern a detector having at least two detection zones (la, lb, lc, ld), an antenna (3) and a local control unit (2) operatively connected to the detector and the antenna (3) on a first side of the substrate (4),

applying in said pattern spacing means (6) having a height of 5 mm or less, preferably 3 mm or less, to the first side of the substrate (4).

16. Method according to claim 14, wherein the application of the detector, antenna (3), local control unit (2) and spacing means (6) is performed through dry phase patterning.

17. Method according to claim 14, wherein the application of the detector, antenna (3), local control unit (2) and spacing means (6) is performed through printing on the substrate (4) or through fastening by an adhesive.

18. Method for detecting the presence of a fluid using a fluid detection label according to any of the claims 1 to 12, the method comprising the steps of:

receiving at least one detection signal in a local control unit (2) operatively connected to the detection zones (la, lb, lc, ld), and

generating, by the local control unit (2), an alarm signal based on the at least one received detection signal.

19. Method according to claim 18, further comprising determining, by the local control unit (2), an alarm level based on the received at least one detection signal, and wherein the alarm signal is generated based on the determined alarm level.

20. Method according to claim 19, wherein a first level alarm signal is generated if only one detection signal is received by the local control unit (2).

21. Method according to any of claims 18-20, wherein a second level alarm signal is

generated if detection signals are received from two or more detection zones (la, lb, lc, ld) but not more than N detection zones (la, lb, lc, ld), where N is a

predetermined threshold value greater than or equal to two and lower than the total number of detection zones (la, lb, lc, ld).

22. Method according to any of the claims 18 to 21, wherein a third level alarm signal is generated if detection signals are received from a number of detection zones (la, lb, lc, ld) greater than N, where N is a predetermined threshold value greater than or equal to two and lower than the total number of detection zones (la, lb, lc, ld) on the fluid detector label (10).

23. Method according to any of the claims l8to 22, further comprising transmitting, via said antenna (3), said alarm signal to a central control unit (100).

24. Antenna (3) for a fluid detector label (10), wherein the antenna (3) is arranged on a substrate (4) of a fluid detector label (10), said antenna (3) being at an angle from the fluid detector label (10) and said angle further being adjustable.

25. Antenna (3) according to claim 24, wherein the antenna (3) is arranged on flaps (31) protruding from the substrate.

26. Computer program product loadable into a memory communicatively connected or coupled to at least one processor, comprising software or hardware for executing the method according any of the claims 18 to 23 when the program is run on the at least one data processor.