Level sensor for hygiene consumable

Abstract

A sensor arrangement for detecting a filling state of a reservoir of a hygiene consumable comprising a set of sensors arranged along a depletion direction of the reservoir, each sensor being configured to detect presence of hygiene consumable in its respective proximity; a processing section being coupled to said set of sensors for obtaining a presence detection from individual sensors of said set of sensors; and a housing, at least comprising an elongate housing bar accommodating the set of sensors, wherein the housing bar comprises a front side facing in operation the reservoir of hygiene consumable, and wherein the front side comprises a recess toward a sensor of the set of sensors.

Description

[0001] LEVEL SENSOR FOR HYGIENE CONSUMABLE

[0002] Technical field

[0003] The present invention relates to detecting a filling level of a reservoir of a hygiene consumable, such as soap, disinfectant , tissue , towel , and the like . In particular, the present invention relates to reliability of level sensing for a hygiene consumable in a piece of hygiene equipment , such as a dispenser of that consumable .

[0004] Background

[0005] The benefits of proper hygiene , in particular in the form of hand hygiene , are widely acknowledged . It is commonplace that public or commercial facilities such as washrooms in public buildings , of fices , restaurants , airports , hospitals , shopping malls and so on are normally provided with dispensers for various hygiene consumables , for example paper towels , liquid soap, disinfectant , tissues , toilet paper, or sanitary napkins .

[0006] Such consumables are normally stored in dispensers , which may be fixedly located at suitable positions in the washroom or other locations . A dispenser can for example be in the form of a holder for paper towels or tissues , a holder for toilet paper, a holder for diapers , or a container for liquid soap, disinfectant or other consumable . Further, also used items , such as towels or tissues , may still be considered as a hygiene consumable and respective equipment for receiving such used consumables may be waste bins or other receptacles for receiving and containing such used consumables .

[0007] In the above context it is oftentimes desirable to know about the filling level of a piece of hygiene equipment such as a dispenser or waste bin . Usually, knowledge on the filling state is desired in order to initiate and plan the refilling of dispensers , emptying bins or other receptacles , or other service activities . For this purpose , it is already known to provide said hygiene equipment with level sensors that are configured to measure and report a filling state of the respective consumable . Such sensors are usually provided with a sensor arrangement that can detect a measured figure that relates to the filling state ( such as a distance , weight , presence , and the like ) , and some kind of logging and / or reporting function that provides the relevant information to an applicable service entity . For example , the sensors report respective filling states to a service center from which refi lls or replacements can be initiated .

[0008] However, the mentioned consumables are often provided and handled in a somewhat irregular form, in the sense that the outer dimensions and / or shape of a refill or a supply of the consumable may vary despite providing for a well-defined amount of the consumable . For example , a stack of paper towels may contain a well-defined number of towels , but its height and stacking may di f fer from refill to refill . Likewise , a liquid consumable may be precisely measured by its volume , but its optical appearance and density may still vary substantially .

[0009] There is therefore a need for an improved sensor arrangement for detecting a filling state of a hygiene consumable that can be employed in hygiene equipment that provides high quality sensing output despite the variations and irregularities of the consumable . In other words , there is a need for sensor arrangements that can provide reliable information on an amount of consumable and filling state while being tolerant to variations in the appearance of the consumable .

[0010] Summary

[0011] The mentioned problems are solved by the subj ect-matter of the independent claims . Further preferred embodiments are defined in the dependent claims .

[0012] According to an aspect of the present invention, there is provided a sensor arrangement for detecting a filling state of a reservoir of a hygiene consumable comprising a set of sensors arranged along a depletion direction of the reservoir, each sensor being configured to detect presence of hygiene consumable in its respective proximity; a processing section being coupled to said set of sensors for obtaining a presence detection from individual sensors of said set of sensors ; and a housing, at least comprising an elongate housing bar accommodating the set of sensors , wherein the housing bar comprises a front side facing in operation the reservoir of hygiene consumable , and wherein the front side comprises a recess toward a sensor of the set of sensors .

[0013] According to an aspect of the present invention, there is provided a piece of hygiene equipment for dispensing and / or receiving a hygiene consumable , comprising a sensor arrangement according to one of the disclosed embodiments .

[0014] Brief Description of the Drawings

[0015] Embodiments of the present invention, which are presented for better understanding the inventive concepts and which are not to be seen as limiting the invention, will now be described with reference to the Figures in which :

[0016] Figures 1A and IB show a general device embodiment of the present invention for a sensor arrangement detecting a filling state of a reservoir of a hygiene consumable ;

[0017] Figures 2A to 2 F show di f ferent types of hygiene equipment in which a filling state of a reservoir of a hygiene consumable is detected according to embodiments of the present invention;

[0018] Figures 3 , 3A and 3B show general measuring concepts involved in detecting a filling state of a reservoir of a hygiene consumable according to embodiments of the present invention; and

[0019] Figures 4A and 4B show further details of device embodiments of the present invention for a sensor arrangement detecting a f illing state of a reservoir of a hygiene consumable .

[0020] Detailed description

[0021] Figures 1A and IB show a general device embodiment of the present invention for a sensor arrangement detecting a filling state of a reservoir of a hygiene consumable . While Figure 1A shows a sensor arrangement from a lateral perspective , Figure IB shows the sensor arrangement of Figure 1A along the cross-section B . Speci fically, there is shown a sensor arrangement 1 for detecting a filling state of a reservoir of a hygiene consumable . The sensor arrangement 1 comprises a set of sensors 100- 1 , 100-2 , ... 100-n that are arranged along a depletion direction D of the reservoir subj ect to measurement . Each sensor 100-i is configured to detect presence of hygiene consumable in its respective proximity . In this way, a filling state can be derived from information that indicates what sensor ( s ) of the set of sensors " see" consumable ( i . e . detect presence ) and what sensor ( s ) of the set of sensors do not " see" consumable ( i . e . do not detect presence or detect absence ) .

[0022] For this purpose , the set of sensors are arranged along the depletion direction . Further details on measuring presence of consumable are provided elsewhere in the present disclosure and speci fically also in conj unction with Figures 3A & 3B . The extent of said proximity may be defined in terms of exclusive zones in the sense that one sensor monitors one zone in which it can detect presence of hygiene consumable while an adj acent sensor monitors another di f ferent zone . For example , a proximity can be a zone Zi with a diameter ri of , for example , less than 10 cm, preferably less than 5 cm, and which is orienteered toward the reservoir and normal to the depletion direction D . The proximity zones can be partly spherical , cone-like , partly ellipsoidal or also irregular as long as a distinction of di f ferent filling states of the consumable can be obtained .

[0023] The sensor arrangement 1 comprises a processing 120 section being coupled to said set of sensors 100-i for obtaining a presence detection from individual sensors 100-i of said set of sensors . The sensor arrangement 1 can further comprise a memory 130 storing data related to the measurement and reporting process , including program data for instructing the processing section 120 to perform one or more of the actions and functionalities as described elsewhere in the present disclosure . The sensor arrangement 1 may further comprise a communication section 140 for accessing remotely stored data or information and / or forward a report on any measured or determined figure to a network 160 , such as the "Cloud" or the Internet . The sensor arrangement 1 may further comprise a battery or other power supply 150 in the form of any one of a battery cel l , a rechargeable battery, a super-capacitor, an energy harvesting device , a solar or light cell , a e / m-wave receiver, and the like .

[0024] For example , the processing section 120 can be further configured to determine information on the f illing state of the reservoir on the basis of the detected presence of hygiene consumable . And it may accordingly compile a reporting message on the basis of the information indicating the filling state . This message can be sent toward the network 160 over the communication section 140 . For this , any suitable technology and / or protocol may apply, including 2G, GPRS , 3G, UMTS , 4G, LTE , 5G, 6G, Wi-Fi , WLAN, and the like .

[0025] The sensor arrangement 1 comprises a housing 10 , at least comprising an elongate housing bar 11 accommodating the set of sensors 100-i , wherein the housing bar 11 comprises a front side 12 facing in operation the reservoir of hygiene consumable , and wherein the front side 12 comprises a recess 121 toward a sensor of the set of sensors . For example , the sensors 100-i can be mounted on a printed circuit board, PCB, 170 , possibly together with any other suitable component such as the battery 150 and / or the processing unit 120 and the like . The sensors 100-i can be configured to emit and receive a probe signal for detecting the presence of hygiene consumable in its respective proximity . Speci fically, the probe signal may comprise any one of a light signal , an infrared light signal , a laser light signal , an electromagnetic signal , an electric field signal , a radar signal , a sound signal , and an ultrasonic signal .

[0026] The material of said housing bar 11 , and preferably also of the housing 10 , may be transparent to the probe signal in the sense that the probe signal can penetrate through the material with only little attenuation . Naturally, i f the probe signal is for example light in the visible wavelength range , the material should be transparent in this range of wavelengths whilst it does not need to be transparent in the infrared, IR, or ultraviolet , UV . Preferably, a thickness of said housing bar 11 or front side 12 may be smaller in at least part of said recess 121 as compared to at least a remainder of said front side . For example and as shown in inset to Figure IB, a thickness dR may be smaller in at least part of said recess 121 as compared to a thickness dB .

[0027] Figures 2A to 2 F show di f ferent types of hygiene equipment in which a filling state of a reservoir of a hygiene consumable is detected according to embodiments of the present invention . Figure 2A shows a schematic view of a dispenser 2- 1 that is arranged to dispense a hygiene consumable in a liquid form . For example , this may be a soap dispenser or a dispenser for a disinfectant such as alcohol or alcogel . Predominantly for such a dispenser type the depletion direction D will be from the top to the bottom as the supply of the consumable will accumulate toward the bottom . The measured figure may be in relation to a top surface of the supply and a maximum height of the reservoir . A sensor arrangement 1 as described in the respective embodiments of the present disclosure may be arranged as shown .

[0028] Figure 2B shows a schematic view of a dispenser 2-2 that is arranged to dispense a hygiene consumable such as a tissue or paper towel 2000 . The dispenser 2-2 has a reservoir 200 with a given supply 20 of hygiene consumable , in the present exemplary case a stack of paper towels 2000 . A user can take one towel from an opening on a bottom side 19 of the dispenser 2-2 , which will make the reservoir 200 gradually deplete in the depletion region D as the supply 20 diminishes . A sensor arrangement 1 as described in the respective embodiments of the present disclosure may be arranged as shown .

[0029] Figure 2C shows a schematic view o f a similar dispenser 2-3 that is arranged to dispense a hygiene consumable such as a paper napkin, tissue or paper towel . The shown case may be similar as shown that in conj unction with Figure 2B except for that the depletion direction D may be from the bottom to the top . Namely, there exist tissue dispenser that push a supply upwards so that a user can pull out one or more towels / tissues from the top . Mechanical spring action may be involved to push up the tissue supply as consumables are dispensed . This configuration may provide the opportunity for measuring a distance between a sensor position and the position of a well-defined element such as the support that pushes the consumable supply upwards . In this way, the sensor ( e . g . TOF or light ref lection / absorption) may be more independent from the consumable as such as measurement do not depend on optical or other physical properties of the consumable . A sensor arrangement 1 as described in the respective embodiments of the present disclosure may be arranged as shown .

[0030] Figure 2D shows a schematic view of a dispenser 2-4 that is arranged to dispense a hygiene consumable such as a tissue or paper towel 2000 ' . In this case , the consumable is an endless towel supply 2000 ' which may have perforations in between individual towels to be dispensed . Namely, a user can pull on the supply from the bottom side 19 of dispenser 2-4 in which the supply is led upwards and then again over one or more rolls 18 again downwards ( see partial cut outs of the dispenser front and the supply moving downwards ) . The dispenser 2-4 has again a reservoir 200 with a given supply 20 ' of hygiene consumable , in the present exemplary case an endless concatenation of paper towels 2000 ' . Taking one towel from an opening on that bottom side 19 of the dispenser 2-4 will make the reservoir 200 gradually deplete in the depletion region D as the supply 20 ' diminishes . It is noted that in this regard the behaviour is similar to the dispenser 2-2 described in conj unction with Figure 2B, although the consumable will first move upwards and the downwards . Speci fically, a sensor arrangement 1 as described in the respective embodiments of the present disclosure may be arranged in dispenser 2-4 and would operate j ust as in the case of dispenser 2-2 . For this , it may be provided that the paper 2000 ' moves upwards and downwards relatively close to the front and rear dispenser housing wall , whereas the sensor 1 is arranged substantially there in between .

[0031] Figure 2E shows a schematic view of a dispenser 2-5 that is arranged to dispense a hygiene consumable in the form of a roll , such as toilet paper . In such types , a diameter of the roll can act as an end or limit of the supply, whereas the position of the sensor may be again a fixed point for any distance measurements . It is noted that this concept may apply to both types of roll dispensers , namely rolls that supply from the outside ( depletion direction D, distance to be considered between outer roll diameter and sensor position) as well as rolls that supply from the inside ( depletion direction D' , distance to be considered between inner roll diameter and sensor position) . A sensor arrangement 1 as described in the respective embodiments of the present disclosure may be arranged as shown .

[0032] Figure 2 F shows a schematic view o f a piece of hygiene equipment in the form of a waste bin 2- 6 that is arranged to receive a used hygiene consumable in the form of towels , tissues , and the like . In such types , the reservoir is for used consumables and the filling state will increase over time rather than decrease as is the case for the earlier discussed types of hygiene equipment . A full reservoir is then an indication for the need of emptying the bin or replacing a full bin liner with a new one . However, the general concepts of the present invention naturally apply accordingly . Especially, also any considerations relating to a filling state and a depletion direction, in that the reservoir is seen as free capacity to receive further used consumables . Thus , during use of a piece of hygiene equipment of that type the reservoir will al so deplete along a depletion direction, as , for example , the reservoir for holding additional material will deplete upwards , and as shown with the depletion direction D in Figure 2 F, while the bin is in use . A sensor arrangement 1 as described in the respective embodiments of the present disclosure may be arranged as shown .

[0033] Figures 3 , 3A and 3B show general measuring concepts involved in detecting a filling state of a reservoir of a hygiene consumable according to embodiments of the present invention . In the main Figure 3 , there is shown a sensor arrangement 1 with a set of sensors 100 arranged along the depletion direction D of some reservoir 200 . In such a configuration, each sensor 100 is configured to detect presence of hygiene consumable in its respective proximity . This may be implemented by means of light sensors that produce a distingui shable output in relation to whether or not there is supply of consumable next to it ( i . e . in the respective proximity) . In the shown example , the sensor can emit a probe signal P, for example a light signal , and measure a reflected signal for detecting presence of consumable in its respective vicinity . For the upper sensor 100-A there is assumed no presence of consumable in its respective proximity, whereas for a lower sensor 100-B there is assumed presence of consumable in its respective proximity .

[0034] In the magni fication of Figure 3A there is shown the upper sensor 100-A having in this exemplary situation no presence of consumable in its respective proximity . The sensor 100-A may be mounted on a PCB 170 and may face towards the reservoir 200 for detecting presence of consumable therein by, for example , emitting a probe signal P and detecting a corresponding response . For the present situation, the probe signal P will not hit consumable and thus no response is expected . According to the embodiments of the present invention, there is provided the elongate housing bar 11 accommodating sensor 100-A, wherein the housing bar 11 comprises the front side 12 facing in operation the reservoir 200 of hygiene consumable 20 . The front side 12 comprises a recess 121 toward the sensor 100-A so as to minimi ze a distance of a gap between the sensor 100-A and the inner surface of the front side 12 . As compared to a situation without the recess 121 , see dashed line , reflections R of the probe signal P can be minimi zed . Speci fically in the present situation, the probe signal P can thus travel and potentially attenuate in the empty reservoir, while no or substantially reduced reflections R could be mistakenly assumed as pickup for presence of consumable .

[0035] In the magni fication of Figure 3B there is shown the lower sensor 100-B having in this exemplary situation presence of consumable in its respective proximity . The sensor 100-B may be mounted on the same PCB 170 as sensor 100-A and thus the lateral configurations , especially toward the housing parts , may apply accordingly . The sensor 100-B may face towards the reservoir 200 for detecting presence of consumable therein by, for example , emitting again a probe signal P and detecting a corresponding response . For the present situation, the probe signal P will hit consumable and thus a reflected response is expected . As compared to a situation without the recess 121 , see dashed line , reflections R of the probe s ignal P can be minimi zed . Speci fically in the present situation, the probe signal P can thus travel into the reservoir and any reflections detected may be attributed to feedback by the presence of consumable , while no or substantially reduced reflections R could be mistakenly assumed as pickup for presence of consumable . Thus , the embodiments provide in both situations a substantially higher detection reliability ( fidelity) as compared to configurations without a recess 121 at the site of a sensor 100 .

[0036] In an embodiment of the present invention, the processing section 120 can be configured to speci fically contribute to saving power during operation, for example in connection with the power supply 150 of the sensor arrangement 1 . A speci fic search routine could be implemented which considers a sequence of at least steps a ) through d) as set out in the following : In a first step a ) there may be obtained start information indicating an individual sensor to be used as a start sensor . For example , the start information may indicate to the processing section which one of the set of sensors is to be addressed first , i . e . from which sensor there is obtained a presence measurement . In a step b ) there may be addressed the sensor indicated by the start information and obtained a first presence detection result from the addressed sensor . It is noted that this may consume considerable power from the supply 150 . In a step c ) it may have been determined that the first presence detection result indicates no presence of hygiene consumable , and it is then addressed a subsequent sensor arranged downstream relative to the previously addressed sensor and in the depletion direction, and obtain a subsequent presence detection result from the addressed sensor . In a step d) there may be stored information indicating the addressed subsequent sensor as the start information, i f the subsequent presence detection result indicates presence of hygiene consumable . In this way, a minimum of power may be consumed for determining a filling state at least from a point in time when the above sequence is performed repeatedly . Further search routines and sequences may apply in order to iteratively search for a pair of adj acent sensors of which one detects presence of consumable , while the other sensor does not , therefore indicating a level of the supply of consumable in the reservoir . In a related embodiment , the processing section 120 may be configured to repeat a ) through d) periodically and to decrease the time period in between two consecutive runs in relation to the filling state . In this way, an enhanced responsivity can be obtained once the reservoir runs empty . This may be a time when it is of increased interest to know about the filling state as a refill becomes more and more imminent as the reservoir runs empty . The processing section 120 may be further configured to determine the information indicating the filling state of the reservoir of the hygiene consumable on the basis of and / or in relation to the stored start information .

[0037] In a further embodiment , the sensors 100-i may be arranged at a smaller distance to each other toward the end of the depletion direction as compared to the distance to each other toward the start of the depletion direction . With again reference to Figure 1A, the distance between sensors 100- 1 and 100-2 toward the beginning of the depletion direction D may be larger than the distance between sensors 100-n and 100- (n- 1 ) toward the end of the depletion direction D . In this way, an enhanced responsivity and / or granularity can be obtained once the reservoir runs empty . This may be a time when it is of increased interest to know about the filling state as a refill becomes more and more imminent as the reservoir runs empty . Such embodiments increase the measurement resolution for situations in which the reservoir is relatively empty and a refill becomes more imminent .

[0038] Figure 4A shows further details of a device embodiment of the present invention for a sensor arrangement detecting a filling state of a reservoir of a hygiene consumable . Speci fically, there is again shown an excerpt of a sensor arrangement with a housing with a front side 12 facing in operation the reservoir of hygiene consumable . The front side 12 comprises a recess 121 toward a sensor 100 . In this embodiment , an inner face 1210 of the reces s 121 is in direct contact with an outer face 1001 of the sensor 100 . Both faces 1210 and 1001 can be provided with at least a planar part which may establish direct contact for this part so that the faces expel most of the ambient air and form an adhesion that avoids an air gap between the sensor 100 and the front side 12 of the sensor arrangement 1 for eliminating any air / matter- interface reflections . Another option is that the faces at least in some points or areas form a direct contact as shown in the magni fying inset . This considers the situations in which at least one surface , for example that of the sensor or - as shown - that of the recess provides for surface irregularities . The arrangement can, however, be such that direct contact is at least partially achieved ( see point X ) which also reduces undesirable reflections .

[0039] Figure 4B shows further details of a device embodiment of the present invention for a sensor arrangement detecting a filling state of a reservoir of a hygiene consumable . Speci fically, there is again shown an excerpt of a sensor arrangement with a housing with a front side 12 facing in operation the reservoir of hygiene consumable . The front side 12 comprises a recess 121 toward a sensor 100 . In this embodiment , the sensor arrangement further comprises a cast element 180 expelling air between an inner face 1210 of said recess 121 and an outer face 1001 of said sensor 100 . For example , the case element 180 can be formed by an amount of transparent potting material that is applied onto the sensor 100 or onto the recess 121 before the sensors are fixed relative to the housing . The potting material can include a resin, an epoxy or acrylic resin, a heat liqui fiable compound and the like . In this way, ambient air is expelled from between the sensor 100 and the front side 12 of the sensor arrangement 1 for eliminating any air / matter-interf ace reflections . It is noted that element 180 is drawn as a black form which is for illustrative purposes only, as it should have suf ficient transparency for any probe signal employed .

[0040] Although detailed embodiments have been described, these only serve to provide a better understanding of the invention defined by the independent claims and are not to be seen as limiting .

Claims

Claims :1 . A sensor arrangement for detecting a filling state of a reservoir of a hygiene consumable comprising : a set of sensors arranged along a depletion direction of the reservoir, each sensor being configured to detect presence of hygiene consumable in its respective proximity; a processing section being coupled to said set of sensors for obtaining a presence detection from individual sensors of said set of sensors ; and a housing, at least comprising an elongate housing bar accommodating the set of sensors , wherein the housing bar comprises a front side facing in operation the reservoir of hygiene consumable , and wherein the front side comprises a recess toward a sensor of the set of sensors .2 . The sensor arrangement according to claim 1 , wherein the sensors are configured to emit and receive a probe signal for detecting the presence of hygiene consumable in its respective proximity .3 . The sensor arrangement according to claim 2 , wherein the probe signal comprises any one of a light signal , an infrared light signal , a laser light signal , an electromagnetic signal , an electric field signal , a radar signal , a sound signal , and an ultrasonic signal .4 . The sensor arrangement according to claim 2 or 3 , wherein the material of said housing bar, preferably also of said housing, is transparent to said probe signal .5 . The sensor arrangement according to any one of claims 1 to 4 , wherein a thickness of said housing bar is smaller in at least part of said recess as compared to at least a remainder of said front side .6 . The sensor arrangement according to any one of claims 1 to 5 , wherein the processing section is further configured to determine information on the filling state of the reservoir on the basis of the detected presence of hygiene consumable .7 . The sensor arrangement according to claim 6 , wherein the processing section is further configured to compile a reporting message on the basis of the information indicating the filling state .8 . The sensor arrangement according to any one of claims 1 to7 , wherein the processing section is configured to a ) obtain start information indicating an individual sensor to be used as a start sensor ; b ) address the sensor indicated by the start information and obtain a first presence detection result from the addressed sensor ; c ) i f the first presence detection result indicates no presence of hygiene consumable , address a subsequent sensor arranged downstream relative to the previously addressed sensor and in the depletion direction, and obtain a subsequent presence detection result from the addressed sensor ; d) i f the subsequent presence detection result indicates presence of hygiene consumable , store information indicating the addressed subsequent sensor as the start information .9 . The sensor arrangement according to claim 8 , wherein the processing section is further configured to repeat a ) through d) periodically and to decrease the time period in relation to the filling state .10 . The sensor arrangement according to claim 8 or 9 , wherein the processing section is further configured to determine the information indicating the filling state of the reservoir of the hygiene consumable on the basis of and / or in relation to the stored start information .11 . The sensor arrangement according to any one of claims 1 to10 , wherein the sensors are arranged at a smaller distance to each other toward the end of the depletion direction as compared to the distance to each other toward the start of the depletion direction .12 . The sensor arrangement according to any one of claims 1 to11 , wherein an inner face of said recess is in direct contact with an outer face of said sensor .13 . The sensor arrangement according to any one of claims 1 to 11 , further comprising a cast element expelling air between an inner face of said recess and an outer face of said sensor .14 . A piece of hygiene equipment for a hygiene consumable , preferably a dispenser for dispensing said hygiene consumable , comprising a sensor arrangement according to any one of claims 1 to 13 .

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