Patent Publication Number: US-2023139600-A1

Title: Ultraviolet radiation cleaning system for baggage trays in an airport security environment

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation application of International Patent Application No. PCT/EP2022/054233, titled “AN ULTRAVIOLET RADIATION CLEANING SYSTEM FOR BAGGAGE TRAYS IN AN AIRPORT SECURITY ENVIRONMENT”, filed on Feb. 21, 2022, which claims priority to and the benefit of Netherland Patent Application No. 2027720, titled “AN ULTRAVIOLET RADIATION CLEANING SYSTEM FOR BAGGAGE TRAYS IN AN AIRPORT SECURITY ENVIRONMENT”, filed on Mar. 8, 2021, and the specification and claims thereof are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The invention relates to an ultraviolet radiation cleaning system for baggage trays in an airport security environment, comprising a radiation tunnel with an input for dirty trays and an output for clean trays. The ultraviolet radiation cleaning system of the invention is intended to quickly and effectively disinfect the baggage trays that are used for security checks, and to efficiently and reliably eliminate micro-organisms such as bacteria, fungi and viruses from these trays. The term ‘quickly’ relates to the cleaning process taking less than about 30 seconds. The term ‘effectively’ means that after processing the trays, the amount of microorganisms on the trays have been removed for more than about 99% of the original quantity at the infeed of the cleaning system. 
     Existing solutions for cleaning trays with ultraviolet radiation in a passenger security process involve processing trays sequentially. A tray is put on a belt or rollers and goes through a tunnel and comes out clean on the other side. Only when a cleaned tray is taken from the belt or rollers, there is room to deliver the next cleaned tray. The problem with existing solutions is that picking up trays can be done at a faster pace than cleaning trays. The actual situation is even worse, taking into account that a passenger needs on average two trays. In addition, the existing solution requires a labour-intensive process to ensure a sufficient supply of trays to be cleaned. The level of experience of the responsible personnel in timely placing of trays to be cleaned, is at the end of the day decisive for limiting the idle time of the UVC cleaning tunnel. 
     Another disadvantage of existing solutions is that if a passenger picks up a tray, he or she has to wait until the next tray has been cleaned before being able to proceed with two clean trays. Some existing solutions offer the possibility to place two cleaned trays on the outlet belt from the UVC cleaning tunnel. Even then however, a waiting time (idle time) is created for the next passenger, which reduces the flow rate of the security process. This means that a higher than normal number of security setups has to be deployed due to inefficient cleaning. If the maximum capacity of security setups is used, this will consequently lead to waiting times and queues for the actual security process. 
     The invention is intended to provide a solution for the above-mentioned problems. 
     WO2021/022053 discloses a device for disinfecting a container, said device comprising: a housing having an upstream opening, a downstream opening, and an interior; a pathway extending between the upstream opening and the downstream opening; and a light source positioned in proximity to the pathway, wherein the light source is configured to emit an antimicrobial wavelength. 
     Note that this specification refers to various references. Discussion of such references is for a more complete background and is not to be construed as an admission that such references are prior art for patentability purposes. 
     BRIEF SUMMARY OF THE INVENTION 
     According to an embodiment of the present invention, an ultraviolet radiation cleaning system for baggage trays in an airport security environment comprises the features of one or more of the appended claims. 
     In a first aspect of the invention, at the input of the cleaning tunnel a first buffering zone is provided for a stack of dirty trays, and at the output of the cleaning tunnel a second buffering zone is provided for a stack of clean trays. Accordingly, the invention makes cleaning of trays possible by UVC lighting in an airport security environment, whereby a continuously replenished stack/batch of trays can be processed, by destacking the trays, cleaning the trays individually and then stacking the trays at the output buffering zone. As will be explained hereinafter there are several options to stack the trays at the output buffering zone. 
     Preferably a destacking system is provided at the input for removal of an individual dirty tray from the stack of dirty trays in the first buffering zone, and a first transfer mechanism to receive said individual dirty tray from the destacking system and to supply said individual dirty tray taken from the stack of dirty trays to the radiation tunnel. 
     Accordingly, it is also preferred that a transfer mechanism is provided at the output to transfer an individual cleaned tray from the radiation tunnel to a stacking system for receiving such individual cleaned tray and to supply that individual cleaned tray to the stack of clean trays in the second buffering zone. 
     Suitably the destacking system and/or the stacking system comprises four tray handling organs that are operative near corner points of the trays. In this way the handling of the trays can be carried out efficiently and reliably. 
     Each tray handling organ can be effective and yet be provided at low cost, when it comprises two flanges that share a common vertical axis, wherein the said two flanges are jointly rotatable around said vertical axis, and wherein said two flanges define a slit between the two flanges which is equipped to receive an edge from a tray to be lifted or lowered, wherein the two flanges have obliquely oriented surfaces that are facing each other and that delimit the slit for the edge of the tray so as to arrange that rotation of the tray handling organ will cause the slit to change in height. Accordingly, the tray that is handled will be correspondingly lifted or lowered. 
     In a first embodiment of the system of the invention, the second buffering zone at the output is arranged to receive and add an individual cleaned tray to the bottom of the stack of cleaned trays. 
     Desirably the first embodiment is arranged such that the second buffering zone at the output is equipped with a first sensor for monitoring the height of the stack of cleaned trays. 
     In a second embodiment of the system of the invention, the second buffering zone at the output is arranged to receive and add an individual cleaned tray to the top of the stack of cleaned trays. 
     Desirably the second embodiment is arranged such that the system is provided with a control system and a second sensor to monitor the altitude of the top of the stack of cleaned trays so as to maintain this altitude. 
     Objects, advantages and novel features, and further scope of applicability of the present invention will be set forth in part in the detailed description to follow, taken in conjunction with the accompanying drawings, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The accompanying drawings, which are incorporated into and form a part of the specification, illustrate one or more embodiments of the present invention and, together with the description, serve to explain the principles of the invention. The drawings are only for the purpose of illustrating one or more embodiments of the invention and are not to be construed as limiting the invention. In the drawings 
         FIGS.  1 A,  1 B,  1 C and  1 D  are illustrations from a transparent side view, a side view, a frontal view and a top view respectively of a first system according to an embodiment of the present invention; 
         FIGS.  2 A,  2 B and  2 C  are illustrations of a system according to an embodiment of the present invention in an airport security environment; 
         FIG.  3    is an illustration of a single tray handling organ to be placed near a corner point of a tray or trays to be handled according to an embodiment of the present invention; 
         FIGS.  4 A,  4 B,  4 C,  4 D,  4 E,  4 F,  4 G,  4 H,  4 I, and  4 J  are illustrations showing operation of the first system according to an embodiment of the present invention; 
         FIGS.  5 A and  5 B  are illustrations from a transparent side view and a side view respectively of a second embodiment of a system according to the invention; 
         FIGS.  6 A,  6 B and  6 C  show three variations on the second embodiment of the system of the invention; and 
         FIGS.  7 A,  7 B,  7 C,  7 D,  7 E,  7 F,  7 G,  7 H,  7 I,  7 J,  7 K,  7 L,  7 M,  7 N,  7 O,  7 P,  7 Q,  7 R,  7 S,  7 T,  7 U,  7 V,  7 W,  7 X,  7 Y and  7 Z  are illustrations showing operation of the second embodiment of the system of the invention. 
     
    
    
     Note that, while the above refers to a “first” and “second” embodiment, such should not be interpreted to mean that the first embodiment is a preferred embodiment or that there are only two embodiments of the present invention. References to a “first” and “second” embodiment is simply for ease of describing variations of the present invention. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Whenever in the figures the same reference numerals are applied, these numerals refer to the same parts. 
       FIGS.  1 - 4    relate to a first embodiment of the ultraviolet radiation cleaning system of the invention.  FIGS.  1 A- 1 D  show the ultraviolet radiation cleaning system for baggage trays in an airport security environment as depicted in  FIGS.  2 A- 2 C , comprising a radiation tunnel  7  with an input  1  for dirty trays and an output  8  for clean trays  10 , wherein the input  1  is equipped with a first buffering zone  5  for a stack  4  of dirty trays, and the output  8  is equipped with a second buffering zone  13  for a stack  12  of clean trays. 
     It is schematically shown in  FIGS.  1 A- 1 D  that at the input  1  a destacking system  2  is provided for removal of an individual dirty tray  3  from the stack  4  of dirty trays in the first buffering zone  5 , and a first transfer mechanism  6  to receive said individual dirty tray  3  from the de-stacking system  2  and to supply said individual dirty tray  3  taken from the stack  4  of dirty trays to the radiation tunnel  7 . 
     It is further shown in  FIGS.  1 A- 1 D  that at the output  8  a transfer mechanism  9  is provided to transfer an individual cleaned tray  10  from the radiation tunnel  7  to a stacking system  11  for receiving such individual cleaned tray  10  and to supply that individual cleaned tray  10  to the stack  12  of clean trays in the second buffering zone  13 . 
     It is remarked that the destacking system  2  and/or the stacking system  11  comprises four tray handling organs  16  that are operative near corner points of the trays  3 ,  10 . One tray handling organ  16  is shown in  FIG.  3   . This  FIG.  3    shows that such a tray handling organ  16  comprises two flanges  17 ,  18  that share a common vertical axis  19 , wherein the said two flanges  17 ,  18  are jointly rotatable around said vertical axis  19 . The two flanges  17 ,  18  define a slit  20  between the two flanges  17 ,  18  which is equipped to receive an edge from a tray  3 ,  10 , wherein the two flanges  17 ,  18  have obliquely oriented surfaces  17 ′,  18 ′ that are facing each other and that delimit the slit  20  to receive an edge of the tray  3 ,  10  so as to arrange that rotation of the tray handling organ  16  will cause the slit  20  to change in height. Accordingly, also the tray  3 ,  10  will be changed in height. 
     Particular for this first embodiment of the ultraviolet radiation cleaning system of the invention as depicted in  FIGS.  1 - 4   , is that the second buffering zone  13  at the output  8  is arranged to receive and add an individual cleaned tray  10  to the bottom of the stack  12  of cleaned trays. 
     The operation of this first embodiment of the ultraviolet radiation cleaning system of the invention, will be further explained hereinafter with reference to  FIGS.  4 A- 4 J . 
       FIG.  4 A : Supply of trays. Trays are provided on the stack  4  at the input buffering zone  5 . 
     There is always one tray in the tray handling organs 2 on the input side and one tray in the tray handling organs  11  on the output side. This is to prevent a passenger or coworker from getting their hands/arms into the cleaning system. Furthermore, the tray in the tray handling organs  2 ,  11  serves to shield the UVC light of the lamps  14 . If the stack  4  of trays is too high, the tray handling organs  2  will stop and a warning light will flash. The detection of whether the stack  4  is too high can be determined with a sensor. 
       FIG.  4 B : Destacking. The stack  4  at the infeed is destacked per tray by means of four tray handling organs  2 , each with its own motor. The tray  3  lands on lift arms of a lift mechanism  6 . 
       FIG.  4 C : Controlled placement of tray on rollers. The lift mechanism  6  places the tray  3  on the driven rollers  15 . 
       FIG.  4 D : Cleaning situation  1 . The tray  3  is transported by the driven rollers  15  and cleaned with UVC light from the lamps  14 . The cleaning of the tray  3  starts as soon as it is within reach of the lamps  14  and ends when the tray  3  has been transported from the lamps  14  to the output  8 . 
       FIG.  4 E : Cleaning situation  2 . The tray  3  is transported by the driven rollers  15  and cleaned with UVC light at the bottom, side and top (360 degrees, all sides). The speed of transport of the tray  3  is adjusted to the required UVC exposure time to clean the tray at least 99.9%. The tray handling organs  2  at the input buffering zone  5  place the next tray in the transfer mechanism  6 . 
       FIG.  4 F : controlled placement of a next tray on the rollers  15  while another tray is being exposed to UVC lighting. The transfer mechanism  6  places the next tray on the driven rollers  15 , while the previous tray is illuminated with UVC light. 
       FIG.  4 G : Transport and lighting. The tray that is transported from the lighting position is still illuminated as long as it is within range of the UVC lamps  14 . The next tray is transported and for this purpose the lighting starts as soon as it is in the range of the UVC lamps  14 . 
       FIG.  4 H : Position tray in stacking mechanism. The edge of the cleaned tray  10  is above the guides of the stacking mechanism  11  at the output buffering zone  13 . 
       FIG.  4 I : stacking mechanism. By means of the transfer mechanism  9 , the tray  10  is placed in the tray handling organs  11  that take over the tray  10  for stacking up. 
       FIG.  4 J : Stack up. The tray which was still in the tray handling organs  11  is stacked upwards by the tray handling organs  11  with the upward movement of the tray. The tray  10  remains in the tray handling organs  11  until the next tray is raised, so as to provide that on the one hand access from below is prevented so that passengers and employees cannot enter it with their hand or arm, and on the other hand to shield against UVC light. 
       FIGS.  5 - 7    relate to a second embodiment of the ultraviolet radiation cleaning system of the invention.  FIGS.  5 A- 5 D  show the ultraviolet radiation cleaning system for baggage trays, which, similar to the first embodiment of  FIGS.  1 - 4   , can be applied in an airport security environment as depicted in  FIGS.  2 A- 2 C . The cleaning system according to the second embodiment also comprises a radiation tunnel  7  with an input  1  for dirty trays  3  and an output  8  for clean trays  10 , wherein the input  1  is equipped with a first buffering zone  5  for a stack  4  of dirty trays, and the output  8  is equipped with a second buffering zone  13  for a stack  12  of clean trays. 
     It is schematically shown in  FIGS.  5 A- 5 B  that at the input  1  a destacking system  2  is provided for removal of an individual dirty tray  3  from the stack  4  of dirty trays in the first buffering zone  5 , and a first transfer mechanism  6  to receive said individual dirty tray  3  from the destacking system  2  and to supply said individual dirty tray  3  taken from the stack  4  of dirty trays to the radiation tunnel  7 . 
     It is further shown in  FIGS.  5 A- 5 B  that at the output  8  a transfer mechanism  9  is provided to transfer an individual cleaned tray  10  from the radiation tunnel  7  to a stacking system  11  for receiving such individual cleaned tray  10  and to supply that individual cleaned tray  10  to the stack  12  of clean trays in the second buffering zone  13 . 
     Also, in this second embodiment the destacking system  2  and/or the stacking system  11  comprises four tray handling organs  16  that are operative near corner points of the trays. One tray handling organ  16  is shown in  FIG.  3   .  FIG.  3    shows that such a tray handling organ  16  comprises two flanges  17 ,  18  that share a common vertical axis  19 , wherein the said two flanges  17 ,  18  are jointly rotatable around said vertical axis  19 . The two flanges  17 ,  18  define a slit  20  between the two flanges  17 ,  18  which is equipped to receive an edge from a tray  3 ,  10 , wherein the two flanges  17 ,  18  have obliquely oriented surfaces  17 ′,  18 ′ that are facing each other and that delimit the slit  20  to receive an edge of the tray  3 ,  10  so as to arrange that rotation of the tray handling organ  16  will cause the slit  20  to change in height. Accordingly, also the tray  3 ,  10  will be changed in height. 
     Particular for this second embodiment of the ultraviolet radiation cleaning system of the invention as depicted in  FIGS.  5 - 7   , is that the second buffering zone  13  at the output  8  is arranged to receive and add an individual cleaned tray  10  to the top of the stack  12  of cleaned trays. 
       FIGS.  6 A- 6 C  show three variations to the second embodiment, to note:
     in  FIG.  6 A : Transfer system which lowers stack. Fall distance of tray is short. System detects when a cart is positioned and then places trays on it.   in  FIG.  6 B : Lowerator slowly lowers due to weight of trays. Fall distance of trays is small.   in  FIG.  6 C : Cart where the trays fall onto. This works well because of the shape and nestability of the trays. One tray is attached to the cart to have a correct starting position.   

     The operation of this second embodiment of the ultraviolet radiation cleaning system of the invention and the three mentioned variations to this embodiment, will be further explained hereinafter with reference to  FIGS.  7 A- 7 Z . 
       FIG.  7 A : Supply of trays. Trays are provided on the stack  4  at the input buffering zone  5 . There is always one tray in the tray handling organs  2  on the input side and one tray in the tray handling organs  11  on the output side. This is to prevent a passenger or coworker from getting their hands/arms into the cleaning system. Furthermore, the tray in the tray handling organs  2 ,  11  serves to shield the UVC light from the lamps  14 . If the stack  4  of trays is too high, the tray handling organs  2  will stop and a warning light will flash. The detection of whether the stack  4  is too high can be determined with a sensor. 
       FIG.  7 B : Destacking. The stack  4  at the input buffering zone  5  is destacked per tray by means of four tray handling organs  2 , each with its own motor. 
       FIG.  7 C : Controlled placement of tray on rollers  15 . The transfer mechanism  6  places the tray  3  on the powered rollers  15 . 
       FIG.  7 D : Cleaning. The tray  3  is transported by the driven rollers  15  and cleaned with UVC light with lamps  14  at the bottom, side and top (360 degrees, all sides). The speed of transport of the tray  3  is adjusted to the UVC exposure time that is required to clean the tray at least 99.9%. 
       FIG.  7 E : Clean and destacking the next tray. The tray handling organs  2  at the input buffering zone  5  place the next tray in the transfer mechanism  6 . 
       FIG.  7 F : Clean and place next tray. The transfer mechanism  6  places the next tray on the driven rollers  15 , while the previous tray is still illuminated with UVC light. 
       FIG.  7 G : Cleaning and transportation. The tray that is transported from the exposure position is still illuminated as long as it is within range of the UVC lamps  14 . The next tray is transported and for this purpose the lighting starts as soon as it is in the range of the UVC lamps  14 . 
       FIG.  7 H : Stacking  1 . The cleaned tray  10 ′ is thrown onto the cleaned tray  10 ″ in the tray handling organs  11  at the output buffering zone  13 . This output buffering zone  13  also uses four tray handling organs, each with its own motor. There is always a tray in these four tray handling organs  11  at the output buffering zone  13 , so as to close off access from below so that passengers and employees cannot enter it with their hand or arm, and on the other hand to shield against UVC light from the lamps  14 . 
       FIG.  7 I : Stacking  2 . The cleaned tray  10 ′ lands on the tray  10 ″ which still is in the tray handling organs  11 . 
       FIG.  7 J : Destacking. The tray located in the tray handling organs  11  is destacked and lands on the lift system. The top edge of the tray is detected by a sensor  21 . 
       FIG.  7 K : Lift system-situation  1 . The lift system lowers until sensor  21  is free from detection again. 
       FIG.  7 L : Lift system-situation  2 . Situation in which several trays are stacked and the lift system always drops a tray height, so that sensor  21  is free from detection. 
       FIG.  7 M : Lift system-situation  3 . Situation where the lift system is almost full. The stack has dropped into reach of sensor  22  and sensor  21  is still free from detection. There is still room for one tray. 
       FIG.  7 N : Lift system-situation  4 . Situation where the lift system is full. The stack is still detected by sensor  22  and now also by sensor  21 . No more trays can be added (max 25 trays). 
       FIG.  7 O : Lift system-situation  5 . Situation where the lift system is full. A cart is placed. The lift system lowers and places the stack on the cart. The cart is detected by sensor  23 . If a cart is placed before the lift system is full (and is detected by sensor  23 ), stacking will stop as soon as the lift system is detected by sensor  22 . The lift system then places the trays on the cart. 
       FIG.  7 P : Lift system-situation  6 . If the lift system is full and the cart has not yet been taken out, the process will stop if there is a tray inside and a tray on the tray handling organs  11 . 
       FIG.  7 Q : Lift system-situation  7 . The lift system is full, the cart has not been taken out yet and there is a tray inside and a tray on the tray handling organs  11 . The rollers  15  stop when the tray reaches the last roller. The UVC exposure by lamps  14  stops. The rollers  15  and UVC lighting by lamps  14  start again when the process continues, so when the full cart has been removed. 
       FIG.  7 R : Lift system-situation  8 . The full cart has been removed. The lift system returns to the top to below sensor  21 . 
       FIG.  7 S : Lift system-situation  9 . The UVC lighting starts again, the drive of rollers  15  starts again. The tray in the tray handling organs  11  is destacked and lands on the lift system. The tray is detected by sensor  21 . 
       FIG.  7 T : Lift system-situation  10 . The lift system lowers until sensor  21  is free from detection again in accordance with the previous Lift system-situation  1 . 
       FIG.  7 U : Application of a lowerator. There are now two trays on the tray handling organs  11  at the output, through which the bottom tray can be destacked and stacked on the lowerator. Sensor  23  detects that there is a lowerator below the output. Sensor  22  is not in use with the lowerator. 
       FIG.  7 V : Destacking. The bottom tray is destacked and falls on the lowerator. 
       FIG.  7 W : Lowerator drops. Due to the weight of the tray, the lowerator drops a bit. 
     The moment the lowerator comes to its lowest position and a tray is added that remains detected by sensor  21 , the stack is at maximum height and stacking stops. Other operation is identical with the operation when using a lift system. 
       FIG.  7 X : Detection cart present. There are now two trays on the tray handling organs  11  at the output, allowing the bottom tray to be destacked and stacked on the cart. 
     Sensor  23  detects that there is a cart present at the output. Sensor  22  is not in use when applying a cart. 
       FIG.  7 Y : Destacking. The bottom tray is destacked and falls on the cart. Even at a greater height, the tray falls into the bottom tray due to the nesting of the trays. 
       FIG.  7 Z : Stack on cart. When a tray is added, the stack  12  increases. If a tray remains detected by sensor  21 , the stack is at maximum height and stacking stops. One tray is attached to the cart to have a correct starting position. Other operation is identical to using a lift system. 
     Although the invention has been discussed in the foregoing with reference to an exemplary embodiment of the method of the invention, the invention is not restricted to this particular embodiment which can be varied in many ways without departing from the invention. The discussed exemplary embodiment shall therefore not be used to construe the appended claims strictly in accordance therewith. On the contrary the embodiment is merely intended to explain the wording of the appended claims without intent to limit the claims to this exemplary embodiment. The scope of protection of the invention shall therefore be construed in accordance with the appended claims only, wherein a possible ambiguity in the wording of the claims shall be resolved using this exemplary embodiment. 
     Embodiments of the present invention can include every combination of features that are disclosed herein independently from each other. Although the invention has been described in detail with particular reference to the disclosed embodiments, other embodiments can achieve the same results. Variations and modifications of the present invention will be obvious to those skilled in the art and it is intended to cover in the appended claims all such modifications and equivalents. The entire disclosures of all references, applications, patents, and publications cited above are hereby incorporated by reference. Unless specifically stated as being “essential” above, none of the various components or the interrelationship thereof are essential to the operation of the invention. Rather, desirable results can be achieved by substituting various components and/or reconfiguration of their relationships with one another. 
     Note that in the specification and claims, “about” or “approximately” means within twenty percent (20%) of the numerical amount cited.