Technical field

The inventive concept described herein generally relates to reverse vending machines (RVMs) for receiving, sorting and optionally storing returnable items such as empty or used beverage or food containers like bottles, cans or the like. In particular, the inventive concept relates to receiving compartment of RVMs.

Background

Environmental and economic concerns have spurred significant

developments in the field of facilities for collecting used items such as cans and/or bottles, jars and other containers, preferably for recovering the material for recycling purposes. Today, fully automatic systems are available that are capable of receiving and optionally storing many different types of used containers, or parts of used containers. In RVMs returned items are often exchanged for money or vouchers or other valuables or tokens. If so, there is generally a national standard which regulates: which objects (with respect to e.g. types, sizes and materials) that are to be collected by means of the RVM, which redemption that is to be given in return and preferably how the financial transactions within the redemption system is to be handled.

Some RVMs may be provided with a closeable lid arranged to cover an in- feed of the RVM. Such lids may prevent a user from reaching into moveable components of the device, thus protection the user from injury or harm. European Patent Application No. 3340192 discloses a RVM having such a closeable lid, with a further improvement in that a light curtain with a light beam is provided. The light curtain functions such that when the device is running, the device is immediately shut down when the light beam is broken. Hence, even when the lid is open, the risk of injury or harm is decreased.

However, there is e.g. a need to provide more efficient, yet simple, reliable and space saving RVMs.

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 reverse vending machine arrangement comprising: a reverse vending machine arranged to receive a returnable container, wherein the reverse vending machine comprises: a receiving compartment comprising receiving means for supporting the returnable container during detection and/or inspection of the returnable container; a feed opening arranged to provide access to the receiving compartment; an optical sensor having a first partial field of view which comprises a partial or full view of the returnable container when received and supported by the receiving means a monitored element arranged in a vicinity of, and extending along, the feed opening; a mirror arranged within an interior of the reverse vending machine, wherein the mirror is configured to provide the optical sensor with a second partial field of view covering the monitored element; and an illumination arrangement configured to backlight the monitored element by emitting radiation which directly after transmission through the monitored element is mainly directed towards a space outside of the receiving compartment; a cover element configured to be operated between an open state wherein access to the receiving compartment via the feed opening is provided, and a closed state wherein the cover element is covering the feed opening thus restricting access to the receiving compartment; wherein the reverse vending machine arrangement further comprises: a processing circuitry configured to determine, based on data received from the optical sensor and relating to the second partial field of view, whether an object is obscuring the monitored element when the same is backlit, cease operation of the cover element or move the cover element towards the opened configuration in order to protect the object and/or the reverse vending machine arrangement upon determination that an object is obscuring the monitored element; and to, in response to the determination that an object is obscuring the monitored element, determine, based on data received from the optical sensor relating to the first partial field of view, the presence of a potential returnable container in the receiving compartment.

According to a second aspect of the inventive concept, these and other objects are achieved in full, or at least in part, by a reverse vending machine arrangement comprising:

a reverse vending machine arranged to receive returnable containers, such as bottles or cans of plastic, glass or metal, wherein the reverse vending machine comprises:

a receiving compartment comprising receiving means for supporting a returnable container during detection and/or inspection of the returnable container; a feed opening arranged to provide access for the returnable container to the receiving compartment;

an optical sensor having a first partial field of view which comprises a partial or full view of the returnable container when received and supported by the receiving means;

a monitored element arranged in a vicinity of, and extending along, the feed opening;

a mirror arranged within an interior of the reverse vending machine, wherein the mirror is configured to provide the optical sensor with a second partial field of view covering the monitored element; and

an illumination arrangement configured to backlight the monitored element; wherein the reverse vending machine arrangement further comprises:

a processing circuitry configured to determine, based on data received from the optical sensor relating to the first partial field of view, the presence of a potential returnable container in the receiving compartment, wherein the processing circuitry is further arranged to determine, based on data received from the optical sensor and relating to the second partial field of view, whether an object is obscuring the monitored element when the same is backlit, and to initiate a safety action in order to protect the object and/or the reverse vending machine arrangement upon

determination that an object is obscuring the monitored element.

By monitoring the monitored element via the optical sensor and the second partial field of view, it may be possible to determine whether an object is interfering or at risk of interfering with the reverse vending machine arrangement or a returned item placed therein. In particular, the monitored element is arranged in a vicinity of the feed opening, and accordingly it may be possible to initiate a safety action should it be determined that an object is present in the feed opening.

By devoting the second partial field of view to monitoring the monitored element, a single optical sensor may be used to determine the presence of a potential valid container in the receiving compartment and to monitor the monitored element in order to determine whether an object is obscuring the monitored element. Accordingly, the present inventive concept may provide for a compact reverse vending machine.

The present inventive concept may be further advantageous in that the illumination arrangement is optionally configured to emit radiation which directly after transmission through the monitored element is directed towards a space outside of the receiving compartment. According to one embodiment, all of the radiation, is directed towards a space outside of the receiving compartment directly after transmission through the monitored element. Alternatively, at least 50 %, or at least 75 %, or at least 80 %, or at least 85 %, or at least 90 %, or at least 95 % of the radiation is directed towards a space outside of the receiving compartment directly after transmission through the monitored element. Hereby, radiation emitted by the illumination arrangement may be less likely to interact with a returned container received in the receiving compartment, and/or be sensed by the optical sensor via the first partial field of view. Such interaction with the returned container, or the empty or used container and/or sensing by the optical sensor may interfere with detection, classification, determination, and/or identification of the returned container, or the empty or used container, by the optical sensor via the first partial field of view. In some embodiments, the reverse vending machine arrangement may comprise other illumination arrangements configured to emit radiation which interacts with the returned container, or the empty or used container, thus facilitating classification, determination, and/or identification of the returned container, or empty or used container. For the sake of clarity, it may be noted that classification, determination, and/or identification of the returned container may comprise determining a presence of an item, such as an valid container and/or returnable container.

The processing circuitry may, based on data received form the optical sensor and relating to the second partial field of view, be configured to read predefined or dedicated pixels on the sensor matrix of the optical sensor. The dedicated pixels preferably correspond to the second partial field of view. The processing circuitry may further be configured to detect radiation emitted by the illumination

arrangement, and in case radiation is obscured from reaching the optical sensor, the processing circuitry may determine that an object is obscuring the monitored element. This arrangement may be seen as a form of“border-crossing” function, i.e. where an event in the second partial field of view of the optical sensor causes the processing circuitry to determine that an object is obscuring the monitored element.

As will be further discussed in the detailed description, the processing circuitry may be configured to determine, based on data from the optical sensor and relating to the second partial field of view, that a potential returnable container has been received in the receiving compartment. Hence, the monitored element and the second partial field of view of the optical sensor may provide either or both of an initiation of a safety action, and an initiation of a detecting function, e.g. determining whether a potential returnable container has been received in the receiving compartment. Obscuring of the monitored element may thus cause the processing circuitry to determine that a potential returnable container has been received in the receiving compartment based on data from the first partial field of view. Optionally, cnce it has been determined that a potential returnable container has been received in the receiving compartment, identification of the potential returnable container may be initiated by the RVM. The monitored element may comprise a diffusing element arranged to provide a substantially uniform distribution of radiation in a direction along the feed opening. diffuse radiation. In particular, the diffusing element may be arranged to diffuse radiation directed towards the optical. Continuous and/or uniform backlighting of the monitored element may be beneficial in that gaps in the backlighting of the monitored element may be eliminated or reduced, thereby facilitating the detection of thin objects. The diffusing element may be arranged to provide a uniform distribution of radiation emitted by the illumination arrangement along the feed opening. The diffusing element may form part of the monitored element. The features above, singularly or in any combination, may provide for that the intensity of radiation detected, via the second partial field of view, by each pixel of the optical sensor associated with the monitored element, may be normalized and/or the same. The diffusing element may be arranged to provide a uniform intensity of received radiation by the optical sensor via the second partial field of view.

The illumination arrangement may be configured to provide pulses of radiation, and the optical sensor may be configured to work in synchronization to such pulses of radiation. Hereby, a high intensity of the illumination arrangement may be achieved, i.e. high lux, while reducing energy consumption. Having an illumination arrangement with high lux may be advantageous in that the radiation provided and/or detected by the optical sensor via the second partial field of view may be more intense than incident sunlight or stray light. Thus, the optical sensor may be capable of discerning the monitored element also when there is incident light or straylight originating from light sources outside the RVM.

The terms‘valid item’,‘valid container’ or‘returnable container’ refers to an item or container that is accepted and not rejected by the RVM, optionally in return for a redemption. The term item or container may refer to a used or emptied beverage and/or food container, such as a can, bottle, jar, or the like. Additionally, the content of the container has preferably been fully, partly, or substantially removed before it is put in the RVM.

The terms“closing element” and“cover element” are used interchangeably Furthermore, the terms“configuration” and“state” are used interchangeably.

In relation to this invention the term“the presence of a potential returnable container” refers to an item that has been put in the RVM, and which might be an item which is to be accepted by the RVM (a valid item or a valid container), but it might also be an invalid object that is to be rejected by the RVM (and invalid item such as a shoe, or an invalid container which is e.g. not part of the redemption system). The term‘potential returnable container’ in the context of determining the presence of a potential returnable container in the receiving compartment, implies that it may not be necessary to determine whether a container received in the receiving compartment is a valid container which is accepted by the reverse vending machine. In some embodiments, it may be sufficient to determine that an object resembling a valid container which is to be accepted by the reverse vending machine has been received in the receiving compartment or only that an object has been received in the receiving compartment. Further determination of the received container may be performed for example after a closing element of the reverse vending machine arrangement has been closed, thus restricting access to the receiving compartment. The closing element will be further discussed throughout the present disclosure.

The term‘object’ may in some cases refer to a user, and in particular to a part of a user such as a hand, one or more fingers, or an arm. In such cases, the safety action may primarily prevent or mitigate injuries of the user caused by the reverse vending machine. However, the safety action may also in such cases prevent or mitigate damage to the reverse vending machine arrangement caused by the object.

The term‘object’ may in some cases refer to a potential returnable container.

The term‘object’ may in some cases refer to an additional container with respect to a potential returnable container already received in the receiving compartment. In some cases the term‘object’ may refer to an unidentified object. In such cases, the safety action may prevent or mitigate damage to the reverse vending machine arrangement caused by the object.

The reverse vending machine may further comprise a closing element configured to be operated between an opened configuration wherein access to the receiving compartment via the feed opening is provided, and a closed configuration wherein the closing element is covering the feed opening thus restricting access to the receiving compartment; wherein the safety action comprises ceasing operation of the closing element or moving the closing element towards the opened configuration. The closing element may provide for that outside light is restricted from entering the receiving compartment. This may be beneficial for various illumination techniques utilized to identify the properties of the container received in the compartment.

Further, the closing element may restrict or prevent a user from accessing the receiving compartment when the reverse vending machine is processing the received container, e.g. identifying, classifying, validating, shredding and/or compacting the container. By having a safety action comprising ceasing operation of the closing element or moving the closing element towards the opened configuration, it may be possible to prevent a used from being injured by the closing element.

The monitored element may be arranged out of line of sight of the optical sensor within the first partial field of view. Such an arrangement of the monitored element may provide for a more compact arrangement of the reverse vending machine arrangement, since the optical sensor does not need a line of sight of the monitored element in the first partial field of view.

The monitored element may be arranged in the interior of the RVM and optionally inside of the feed opening. However, other arrangements are envisioned, for example arranging the monitored elements such that at least part of the monitored element is inside of the feed opening and at least part of the feed opening is outside of the feed opening. It may also be possible to arrange the monitored element outside of the feed opening, and on the front or housing of the RVM.

According to one example, the Registerable Intensity of the Illumination Arrangement is at least 1/1000, or at least 1/100 , or at least 1/10 of the intensity of the Standard Solar Spectrum after Attenuation and within the Detectable Wavelength Range.

A high intensity is advantageous as it allows the sensor to differentiate between radiation emitted by the illumination arrangement and sunlight reflected by the monitored element via the mirror and onto the sensor, i.e. the illumination may be configured so it is capable of outshine the sunlight. The amount of light needed may vary dependent on the amount of sunlight or ambient light present at the location where the machine is used. The intensity of the illumination arrangement may be tuneable.

Herein, the term“Detectable Wavelength Range” refers to the range of wavelengths which the image sensor is capable of register and output

information/data about, e.g. information regarding a change in intensity (which change in intensity is sufficiently large to be detectable, e.g. above the background noise level).

Herein, the term“Registerable Intensity of the Illumination Arrangement” refers to the intensity of the radiation within the Detectable Wavelength Range, which is emitted by said illumination arrangement, transmitted through the monitored element, reflected via said mirror and impinging on said optical sensor.

Herein, the term The term“Attenuation in Optical Path” refers to the attenuation of the radiation intensity when passing from the monitored element, being reflected by via said mirror and before impinging on said optical sensor, if any. Illustrative example: if a filter is arranged after the mirror and before the reflected light impinges on said optical sensor, which filer only has a high transmittance for a portion of the Detectable Wavelength Range (called the transmitted wavelengths) - the low-transmitted wavelengths will be subject to a larger attenuation compared to the transmitted wavelengths. I.e. the Attenuation of Radiation Intensity will be larger for the low-transmitted wavelengths compared to the transmitted wavelengths

Herein, the term“Standard Solar Spectrum” is the standard spectra from AM 1.5 as defined by The American Society for Testing and Materials. See also Figure 2 of the Article published by Laser Focus World, PHOTOVOTAICS: Measuring the ‘Sun’, published 21st May 2009. https://www.laserfocusworld.com/lasers- sources/article/16566681 /photovoltaics-measuring-the-sun.

Herein, the term“Standard Solar Spectrum after Attenuation” refers to the “Standard Solar Spectrum” after having been compensated for any Attenuation in Optical Path.

The illumination arrangement may be configured to provide this intensity as pulses at e.g. a rate which is perceived by the user as constant illumination, at e.g.

50 or 60 Hz, so the high intensity of the illumination does not disturb the users of the machine.

The illumination arrangement may be configured to provide, at least momentarily, at least [amount of radiation]10 lux, or at least 50 lux, or at least lux 100 lux, or at least 500 lux, or at least 750 lux to the optical sensor via the mirror.

According to one embodiment the monitored element is arranged along one side of the in feed opening. Optionally, the monitored element is arranged along the side of the infeed opening which the closing element reaches last during its closing action. Additionally or alternatively, infeed opening is rectangular, and the monitored element is arranged along one of the longest sides of the rectangular infeed opening.

The back-lit area of the monitored element may be continuous or

discontinuous, and the back-lit area of the monitored element may extend along at least 80 %, or at least 90 %, or at least 95 % of the in feed opening. The back-lit area of the monitored element may have any shape, e.g. elongated or rectangular.

The reverse vending machine may be configured to receive emptied or used food and/or beverage containers.

The optical sensor may e.g. be a line sensor or a matrix sensor or a camera such as a CCD camera [the list is non-exhaustive].

The reverse vending machine may further comprise at least one background panel arranged behind the container when received and supported by the receiving means with respect to the optical sensor, and wherein the at least one background panel forms a background to the received container as seen from the optical sensor in the first partial field of view. Hereby, a contour of the returned container, or empty or used container, received in the receiving compartment may be more defined and easier to detect by the optical sensor. The at least one background may be illuminated backlit by a background illumination arrangement, preferably different from the illumination arrangement used to back-light the monitored element.

According to one embodiment the monitored element is arranged beyond the background panel, i.e. the distance between the optical sensor and the center of the monitored element is longer than the distance between the optical sensor and the background panel. Additionally or alternatively, the monitored element is arranged above the background panel in the vertical direction, while being arranged above the background panel the monitored element is optionally arranged to the side of the background panel in the horizontal direction.

According to one embodiment, only the monitored element, out of the monitored element and the background panel, is backlit by the illumination arrangement. As discussed earlier in the present disclosure, a possible advantage with this arrangement is that radiation emitted by the illumination arrangement may be less likely to interact with a returnable container received in the receiving compartment. Such interaction with the returnable container may interfere with detection, classification, determination, and/or identification of the returnable container by the optical sensor via the first partial field of view.

The illumination arrangement may comprise at least one LED. The at least one LED may be configured to emit infrared radiation, UV radiation, and/or visible light. Accordingly, the optical sensor may be configured to detect infrared radiation, UV radiation, and/or visible light. The optical sensor may be an imaging sensor.

According to a third aspect of the inventive concept, these and other objects are achieved in full, or at least in part, by a method for operating a reverse vending machine arrangement comprising: a reverse vending machine arranged to receive a returnable container; a receiving compartment comprising receiving means for supporting returnable container during detection and/or inspection of the returnable container; a feed opening arranged to provide access to the receiving compartment for the returnable container; an optical sensor having a first partial field of view which comprises a partial or full view of the returnable container when received and supported by the receiving means; a monitored element arranged in a vicinity of, and extending along, the feed opening; a mirror arranged within an interior of the reverse vending machine, wherein the mirror is configured to provide the optical sensor with a second partial field of view covering the monitored element; and an illumination arrangement configured to backlight the monitored element by emitting radiation which optionally directly after transmission through the monitored element is mainly directed towards a space outside of the receiving compartment; a cover element configured to be operated between an open state wherein access to the receiving compartment via the feed opening is provided, and a closed state wherein the cover element is covering the feed opening thus restricting access to the receiving compartment; wherein the method comprises: backlighting the monitored element via the illumination arrangement; receiving, from the optical sensor via the second partial field of view, sensor data pertaining to the monitored element; determining, via a processing circuitry and based on the sensor data, whether an object is obscuring the monitored element; if an object is obscuring the monitored element, caseing operation of the cover element or moving the cover element towards the opened state in order to protect the object and/or the reverse vending machine arrangement; and in response to determining that the object is obscuring the monitored element, receiving, from the optical sensor via the first partial field of view, second sensor data, and determining, based on the second sensor data, the presence of a potential returnable container in the receiving compartment.

The method may further comprise receiving, from the optical sensor via the first partial field of view, second sensor data pertaining to a potential returnable container in the receiving compartment; and determining, via the processing circuitry and based on the second sensor data, whether the potential returnable container has been received in the receiving compartment. These steps may be performed before determining whether an object is obscuring the monitored element.

The step of determining whether the potential returnable container has been received in the receiving compartment may be further based on sensor data pertaining to the monitored element. For example, when a returnable container is received in the receiving compartment, it is inserted via the feed opening. The returnable container may thus at some point obscure the monitored element from the optical sensor in the second partial field of view. Such information may be utilized by the processing circuitry in order to determine that a returnable container has been inserted via the feed opening into the receiving compartment.

The method may further comprise initiating a closing of a closing element of the reverse vending machine arrangement. The determination whether an object is obscuring the monitored element may be performed in relation to the initiation of the closing element. For example, the reverse vending machine arrangement may be configured to monitor the monitored element when the closing element is moving towards the closed configuration. In some embodiments, the reverse vending machine arrangement may be configured to monitor the monitored element when the closing element is moving towards the closed configuration and is at least halfway between the opened configuration and the closed configuration.

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 part of a reverse vending machine

arrangement in a cross-sectional view;

FIG. 2 schematically illustrates part of a reverse vending machine in a perspective view;

FIG. 3 schematically illustrates a reverse vending machine in a perspective view.

The figures are not necessarily to scale, and generally only show parts that are necessary in order to elucidate the inventive concept, wherein other parts may be omitted or merely suggested.

Detailed description

FIG. 1 illustrates part of a reverse vending machine 100 arranged to receive a returnable container 102 returned to the reverse vending machine 100. The reverse vending machine 100 may form part of a reverse vending machine arrangement. The reverse vending machine 100 comprises a receiving compartment 104 comprising receiving means 106 for supporting the returned container, or empty or used container, 102 during detection, classification, determination, and/or identification thereof. The receiving means 106 may comprise a supporting surface 103, and may be retractable to further transfer the returnable container 102 by gravity to be further processed by the reverse vending machine 100 upon determination that the returnable container 102 is a returnable container accepted by the reverse vending machine. The supporting surface 103 may be a plate.

The reverse vending machine 100 further comprises a feed opening 108 arranged to provide access to the receiving compartment 104, an optical sensor 110 having a first partial field of view Fi which comprises a partial or full view of the returnable container 102 when received and supported by the receiving means 106. The reverse vending machine 100 further comprises a monitored element 112 arranged in a vicinity of, and extending along, the feed opening 108. The optical sensor 1 10 may be arranged in an optical compartment 11 1. A divider 113 being transmissive to radiation to which the optical sensor 1 10 is sensitive may separate the optical compartment 11 1 from the receiving compartment 104. The optical sensor 110 and the supporting surface 103 may be arranged such that the supporting surface 103 is out of line of sight of the optical sensor 110 in the first partial field of view Fi.

The monitored element 112 may extend along at least one side of the feed opening 108. Here, the monitored element 112 extends in a direction inwards and outwards of the illustrated cross-sectional plane. The extension of the monitored element 112 is more clearly illustrated in FIG. 2. The monitored element 112 may further be arranged out of a line of sight of the optical sensor 110 in the first partial field of view Fi.

The monitored element 112 is here arranged in the interior of the reverse vending machine, inside of the feed opening 108. It is also envisioned that the monitored element may be arranged outside of the interior, outside of the feed opening 108, or with parts of the monitored element 112 being inside of the feed opening 108 and parts of the monitored element 1 12 being outside of the feed opening 108.

The monitored element 112 may be a plate transmissive to radiation emitted by an illumination arrangement which is further discussed below. The monitored element 112 may also be shaped as a semicylinder with its long axis extending along a side of the feed opening. The reverse vending machine 100 further comprises a mirror 1 14 arranged within an interior of the reverse vending machine 100, wherein the mirror 1 14 is configured to provide the optical sensor 1 10 with a second partial field of view F ₂ covering the monitored element 1 12. The mirror 1 14 is here arranged on an upper surface of the interior, above the receiving compartment 104 with respect to gravity when the reverse vending machine 100 is in use. Hereby, the mirror 1 14 may provide the optical sensor 1 10 with a second line of sight l_ ₂ of the monitored element 1 12, wherein the second line of sight passes substantially above a center of the receiving compartment 104, and/or passes above a returnable container received in the receiving compartment 104.

The reverse vending machine 100 further comprises an illumination arrangement 1 16 configured to backlight the monitored element 1 12 by emitting radiation which directly after transmission through the monitored element 1 12 is mainly directed towards a space outside of the receiving compartment 104. The illumination arrangement 1 16 may comprise at least one LED. The illumination arrangement is here arranged in an illumination arrangement compartment 1 18.

The reverse vending machine arrangement further comprises a processing circuitry (not shown) configured to determine, based on data received from the optical sensor 1 10 relating to the first partial field of view Fi, the presence of a potential returnable container in the receiving compartment 104, wherein the processing circuitry is further arranged to determine, based on data received from the optical sensor 1 10 and relating to the second partial field of view F ₂ , whether an object is obscuring the monitored element 1 12 when the same is backlit, and to initiate a safety action in order to protect the object and/or the reverse vending machine arrangement upon determination that an object is obscuring the monitored element 1 12.

The reverse vending machine 100 may further comprise a closing element 120 configured to be operated between an opened configuration wherein access to the receiving compartment 104 via the feed opening 108 is provided, and a closed configuration wherein the closing element 120 is covering the feed opening 108 thus restricting access to the receiving compartment 104. The closing element 120 may comprise a closing plate configured to be retracted into and extracted out of the interior of the reverse vending machine 100. In particular, the closing element 120 may be configured to, when moving from the opened configuration towards the closed configuration, move towards a first side 122 of the feed opening 108. The monitored element 1 12 may be arranged at or in a vicinity of said first side 122 of the feed opening 108. The reverse vending machine 100 may further comprise at least one background panel 124 arranged behind the returnable container 102 when received and supported by the receiving means 106 with respect to the optical sensor 110, wherein the at least one background panel 124 forms a background to the returnable container 102 as seen from the optical sensor 1 10 in the first partial field of view Fi. The background panel 124 may be backlit by a background illumination arrangement (not shown). Regarding the illumination arrangement 116, only the monitored element 112, out of the monitored element 112 and the background panel 124, may be backlit by the illumination arrangement 116.

As seen in the figure, the monitored element is arranged beyond the background panel, i.e. the distance between the optical sensor and the center of the monitored element is longer than the distance between the optical sensor and the background panel. Additionally, the monitored element is arranged above the background panel in the vertical direction, and is also arranged to the side of the background panel in the horizontal direction.

Referring now to FIG. 2, a perspective view of part of a reverse vending machine 100 is illustrated, showing generally the same features as discussed in conjunction with FIG. 1.

Referring now to FIG. 3, a reverse vending machine 100 is illustrated in a perspective view. In this view, the feed opening 108 and the monitored element 1 12 may be more clearly seen. In particular, an extension of the monitored element 1 12 along a first side 122 of the feed opening 108 is apparent.

The following paragraphs will describe methods related to the inventive concept. For clarity and simplicity, the method will be described in terms of‘steps’. It is emphasized that steps are not necessarily processes that are delimited in time or separate from each other, and more than one‘step’ may be performed at the same time in a parallel fashion.

With reference to FIG. 4, in a step 250, a user may initiate a return session via e.g. a user interface of the reverse vending machine arrangement. Upon initiating the return session, the closing element of the reverse vending machine may be set to the opened configuration in a step 252. An item, such as a returnable container container, may then be inserted into the reverse vending machine in a step 254, in particular into the receiving compartment via the feed opening. When inserting the returnable container into the receiving compartment, the monitored element may be at least partly obscured by the returnable container as seen by the optical sensor via the mirror and the second partial field of view. In more detail, in many cases the RVM is configured to accept containers of different sizes, and the larger bottles may obscure the monitored element as seen by the optical sensor while the smaller bottles do not obscure the monitored element as seen by the optical sensor.

Alternatively, all returnable bottles obscure the monitored element, or none of the returnable bottles obscure the monitored element.

In a step 256, the processing circuitry of the reverse vending machine arrangement may accordingly determine, based on data from the optical sensor and relating to the second partial field of view, that a potential returnable container has been received in the receiving compartment. Further, upon such a determination the processing circuitry may optionally initiate a determination, based on data from the optical sensor and relating to the first partial field of view, that a potential returnable container is present in the receiving compartment. In addition or alternatively, the processing circuitry may make such a determination based on data from the optical sensor and relating to the first partial field of view independent of the determination relating to the second field of view. The present inventive concept may be particularly advantageous when in determining that a potential returnable container has been received in the receiving compartment via the optical sensor and the first partial field of view, since radiation emitted by the illumination arrangement is after transmission directed towards a space outside of the receiving compartment. Hence, interference with the optical sensor in the first partial field of view caused by the radiation emitted by the illumination arrangement may be decreased or fully prevented.

In a step 258, upon determining that a potential returnable container has been received in the receiving compartment, a closing of the closing element may be initiated, i.e. the closing element may be set to the closed configuration. During closing of the closing element, the optical sensor may monitor the monitored element in a step 260. If the monitored element during the closing of the closing element is obscured by an object as seen by the optical sensor via the second partial field of view, the processing circuitry may in a step 262 determine that an object is obscuring the monitored element, and the closing of the closing element may be ceased, or the closing element may be moved towards the opened configuration.

The reverse vending machine arrangement may subsequently, e.g. after a predetermined period of time or upon a user instructing the reverse vending machine to continue with the return session, try to close the closing element in a step 264.

Upon closing the closing element, i.e. when the closing element is in the closed configuration, the processing circuitry may in a step 266 classify, determine, and/or identify the potential returnable container based on data received from the optical sensor via the first partial field of view. The background panel and a background illumination arrangement backlighting the background panel may facilitate such classification, determination, and/or identification. The closing element being in the closed configuration may further facilitate such classification, determination, and/or identification by restricting outside light from reaching the receiving compartment.

If the potential returnable container is determined to be a returnable container accepted by the reverse vending machine, the receiving means supporting the returnable container in the receiving compartment may be moved, retracted and/or opened in a step 268 such that the returnable container may be removed from the receiving compartment, e.g. via gravity, to be further processed by the reverse vending machine.

After the returnable container has been removed from the receiving compartment, the closing element may be opened similarly to step 250, and a new cycle may begin, e.g. another potential returnable container may be inserted into the receiving region via the feed opening, and the processing circuitry may again determine, based on data from the optical sensor and relating to the second partial field of view and/or the first partial field of view, that a potential returnable container has been received in the receiving compartment.

The return session may be terminated in a step 270 after a predetermined period of time has passed without determining a potential returnable container in the receiving compartment, and/or upon a user initiated termination via the user interface of the reverse vending machine arrangement.

With reference to FIG. 5, a method for operating a reverse vending machine arrangement will be described. The reverse vending machine arrangement comprises a reverse vending machine arranged to receive a returnable container container returned to the reverse vending machine, wherein the reverse vending machine comprises: a receiving compartment comprising receiving means for supporting the returnable container during detection and/or inspection of the returnable container; a feed opening arranged to provide access to the receiving compartment; an optical sensor having a first partial field of view which comprises a partial or full view of the returnable container when received and supported by the receiving means; a monitored element arranged in a vicinity of, and extending along, the feed opening; a mirror arranged within an interior of the reverse vending machine, wherein the mirror is configured to provide the optical sensor with a second partial field of view covering the monitored element; and an illumination arrangement configured to backlight the monitored element by emitting radiation which directly after transmission through the monitored element is mainly directed towards a space outside of the receiving compartment. The method comprises: a step 280 of backlighting the monitored element via the illumination arrangement; a step 282 of receiving, from the optical sensor via the second partial field of view, sensor data pertaining to the monitored element; a step 284 of determining, via a processing circuitry and based on the sensor data, whether an object is obscuring the monitored element; and if an object is obscuring the monitored element, a step 286 of initiating a safety action in order to protect the object and/or the reverse vending machine arrangement.

The method may further comprise a step 288 of receiving, from the optical sensor via the first partial field of view, second sensor data pertaining to a potential returnable container in the receiving compartment; and step 290 of determining, via the processing circuitry and based on the second sensor data, whether the potential returnable container has been received in the receiving compartment.

It is to be understood that any one of the steps disclosed in conjunction with FIG. 4 may be incorporated into the method disclosed in conjunction with FIG. 5.

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.

Itemized list of embodiments

Item 1. A reverse vending machine arrangement comprising:

a reverse vending machine arranged to receive returnable containers, such as bottles or cans of plastic, glass or metal, wherein the reverse vending machine comprises:

a receiving compartment comprising receiving means for supporting a returnable container during detection and/or inspection of the returnable container;

a feed opening arranged to provide access for the returnable container to the receiving compartment;

an optical sensor having a first partial field of view which comprises a partial or full view of the returnable container when received and supported by the receiving means;

a monitored element arranged in a vicinity of, and extending along, the feed opening;

a mirror arranged within an interior of the reverse vending machine, wherein the mirror is configured to provide the optical sensor with a second partial field of view covering the monitored element; and

an illumination arrangement configured to backlight the monitored element by emitting radiation which directly after transmission through the monitored element is mainly directed towards a space outside of the receiving compartment;

wherein the reverse vending machine arrangement further comprises:

a processing circuitry configured to determine, based on data received from the optical sensor relating to the first partial field of view, the presence of a potential returnable container in the receiving compartment, wherein the processing circuitry is further arranged to determine, based on data received from the optical sensor and relating to the second partial field of view, whether an object is obscuring the monitored element when the same is backlit, and to initiate a safety action in order to protect the object and/or the reverse vending machine arrangement upon determination that an object is obscuring the monitored element.

Item 2. The reverse vending machine arrangement according to item 1 , wherein the reverse vending machine further comprises a closing element configured to be operated between an opened configuration wherein access to the receiving compartment via the feed opening is provided, and a closed configuration wherein the closing element is covering the feed opening thus restricting access to the receiving compartment;

wherein the safety action comprises ceasing operation of the closing element or moving the closing element towards the opened configuration.

Item 3. The reverse vending machine arrangement according to item 1 or 2, wherein the monitored element is arranged out of line of sight of the optical sensor within the first partial field of view.

Item 4. The reverse vending machine arrangement according to any one of the

preceding items, wherein the monitored element is arranged in the interior, inside of the feed opening.

Item 5. The reverse vending machine arrangement according to any one of the

preceding items, wherein the reverse vending machine is configured to receive empty or used food and/or beverage containers.

Item 6. The reverse vending machine arrangement according to any one of the

preceding items, wherein the reverse vending machine further comprises at least one background panel arranged behind the returnable container when received and supported by the receiving means with respect to the optical sensor, wherein the at least one background panel forms a background to the returnable container as seen from the optical sensor in the first partial field of view.

Item 7. The reverse vending machine arrangement according to item 6, wherein only the monitored element, out of the monitored element and the background panel, is backlit by the illumination arrangement.

Item 8. The reverse vending machine arrangement according to any one of the

preceding items, wherein the illumination arrangement comprises at least one LED.

Item 9. A method for operating a reverse vending machine arrangement comprising: a reverse vending machine arranged to receive a returnable container returned to the reverse vending machine, wherein the reverse vending machine comprises:

a receiving compartment comprising receiving means for supporting the returnable container during detection and/or inspection of the returnable container;

a feed opening arranged to provide access to the receiving compartment; an optical sensor having a first partial field of view which comprises a partial or full view of the returnable container when received and supported by the receiving means;

a monitored element arranged in a vicinity of, and extending along, the feed opening;

a mirror arranged within an interior of the reverse vending machine, wherein the mirror is configured to provide the optical sensor with a second partial field of view covering the monitored element; and

an illumination arrangement configured to backlight the monitored element by emitting radiation which directly after transmission through the monitored element is mainly directed towards a space outside of the receiving compartment;

wherein the method comprises:

backlighting the monitored element via the illumination arrangement;

receiving, from the optical sensor via the second partial field of view, sensor data pertaining to the monitored element;

determining, via a processing circuitry and based on the sensor data, whether an object is obscuring the monitored element; and if an object is obscuring the monitored element, initiating a safety action in order to protect the object and/or the reverse vending machine arrangement.

Item 10. The method according to item 9, further comprising:

receiving, from the optical sensor via the first partial field of view, second sensor data pertaining to a potential returnable container in the receiving compartment; and

determining, via the processing circuitry and based on the second sensor data, whether the potential returnable container has been received in the receiving compartment. Item 1 1. The method according to item 10, wherein the step of determining whether the potential returnable container has been received in the receiving compartment is further based on sensor data pertaining to the monitored element.