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Title:
SYSTEM AND METHOD FOR BUFFERING PIECES OF LUGGAGE
Document Type and Number:
WIPO Patent Application WO/2012/087137
Kind Code:
A1
Abstract:
The present invention relates to a system for buffering pieces of luggage. The system comprises racks (3) and associated carriers (40), each carrier having a supporting surface for supporting individual pieces of luggage, which carriers can be moved between adjacent racks by lifts (5), between storage positions (4) and a transfer position (32) of a transfer station (30). At least some of the transfer stations comprise moving means (34) provided with a pusher element (33) for each transfer station for pushing a buffered piece of luggage off the supporting surface of a carrier (40) positioned at the transfer position. The invention also provides a method for buffering pieces of luggage.

Inventors:
BOSSINK GERARDUS JOHANNES (NL)
VOS ANTONIUS LAURENTIUS PETRUS (NL)
Application Number:
PCT/NL2011/050884
Publication Date:
June 28, 2012
Filing Date:
December 21, 2011
Export Citation:
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Assignee:
VANDERLANDE IND BV (NL)
BOSSINK GERARDUS JOHANNES (NL)
VOS ANTONIUS LAURENTIUS PETRUS (NL)
International Classes:
B65G1/137; B65G1/04
Domestic Patent References:
WO2005002999A12005-01-13
WO2009127383A12009-10-22
WO2008094033A12008-08-07
WO2005002999A12005-01-13
WO2008094033A12008-08-07
Foreign References:
EP0678461A11995-10-25
EP1091895A12001-04-18
DE4220117A11993-02-11
EP2025682A22009-02-18
Attorney, Agent or Firm:
DOHMEN, Johannes, Maria, Gerardus (P.O. Box 645, AP Eindhoven, NL)
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Claims:
CLAIMS

1. A system for buffering pieces of luggage, comprising a number of racks arranged parallel to each other, each rack comprising storage positions arranged beside and above each other for pieces of luggage, a number of lifts which are movable along paths of movement between adjacent racks both for transferring a piece of luggage to be buffered to a storage position and for picking up a buffered piece of luggage from a storage position, a number of transfer stations, each comprising at least one transfer position positioned along part of a path of movement of at least one lift for presenting pieces of luggage to be buffered to a lift at a transfer position and/or for picking up a buffered piece of luggage from a lift, characterised in that the device comprises carriers associated with the racks, each carrier having a supporting surface for supporting individual pieces of luggage, which carriers can be moved between storage positions and a transfer position by the lift, each transfer position being arranged for receiving a carrier, and in that at least some of the transfer stations comprise moving means provided with a pusher element for each transfer station for pushing a buffered piece of luggage off the supporting surface of a carrier positioned at the transfer position.

2. A system according to claim 1 , characterised in that the moving means are at least partially accommodated within a rack.

3. A system according to claim 1 or 2, characterised in that the system comprises a supply conveying system for supplying pieces of luggage to be buffered to a transfer station.

4. A system according to claim 3, characterised in that the supply conveying system comprises a supply conveyor.

5. A system according to claim 4, characterised in that the supporting surface of a carrier positioned at a transfer position is located at the same vertical level as the conveying surface of the supply conveyor.

6. A system according to claim 4 or 5, characterised in that the system comprises further moving means for moving pieces of luggage to be buffered directly present on the supply conveyor off said supply conveyor and onto or at least in the direction of the transfer position.

7. A system according to claim 6, characterised in that said further moving means comprise further pusher elements for pushing pieces of luggage to be buffered directly present on the supply conveyor off the supply conveyor and onto or at least in the direction of the transfer position.

8. A system according to any one of claims 4, 5, 6 or 7, characterised in that the supply conveyor is made up of a train of sorting units that can be conveyed along an endless conveying path, which sorting units each comprise a further carrier, each carrier having a further supporting surface for directly supporting an individual piece of luggage.

9. A system according to claims 7 and 8, characterised in that each sorting unit comprises a further pusher element above the associated further supporting surface, which pusher element is laterally movable relative to the conveying path, in the direction of the transfer conveyor, at the location of the transfer conveyor for pushing a piece of luggage to be buffered off said further supporting surface and onto or at least in the direction of the transfer station.

10. A system according to claim 7, characterised in that said further pusher elements take up a stationary position along the conveying path.

11. A system according to any one of claims 4 - 10, characterised in that the supply conveyor is a belt conveyor.

12. A system according to any one of the preceding claims, characterised in that the system comprises a discharge conveying system for discharging buffered pieces of luggage from a transfer station, wherein the moving means are designed to push a buffered piece of luggage onto or at least in the direction of the discharge conveying system.

13. A system according to claim 12, characterised in that the discharge conveying system comprises a discharge conveyor.

14. A system according to claim 13, characterised in that the supporting surface of a carrier positioned at a transfer position is located at the same vertical level as the conveying surface of the discharge conveyor.

15. A system according to claim 4 and claim 13, characterised in that the discharge conveyor and the supply conveyor are made up of a common conveyor.

16. A system according to claim 3 and claim 12, characterised in that at least some of the transfer stations are provided with at least one transfer conveyor for conveying a piece of luggage to be buffered from the supply conveying system to the transfer position of the transfer station in question and/or for conveying a buffered piece of luggage from the transfer position of a transfer station to the discharge conveying system.

17. A system according to claim 16, characterised in that the discharge conveyors can be driven in two opposite directions for conveying a piece of luggage to be buffered from the supply conveying system to an unloaded carrier at a transfer position of the transfer station in question and for conveying a buffered piece of luggage from a carrier at a transfer position of the transfer station in question to the discharge conveying system.

18. A system according to claim 16 or 17, characterised in that the transfer conveyor is a belt conveyor.

19. A system according to any one of the preceding claims, characterised in that the carriers are at least substantially plate-shaped.

20. A system according to any one of the preceding claims, characterised in that the carriers have a flat or a slightly concave upper side forming the supporting surface.

21. A method for buffering pieces of luggage, using a system according to any one of the preceding claims, comprising the successive steps of

a supplying a piece of luggage to be buffered by means of a supply conveying system,

b selectively moving the piece of luggage to be buffered off the supply conveying system to the supporting surface of a carrier at a transfer position of a transfer station,

c picking up a carrier with the piece of luggage to be buffered present on the supporting surface thereof from the transfer position, using a movable lift, d moving the carrier with the piece of luggage to be buffered present on the supporting surface thereof to a storage position of a rack by means of the lift, e transferring the carrier with the piece of luggage to be buffered present on the supporting surface thereof to the storage position by means of the lift, f keeping the piece of luggage buffered at the storage position, with the piece of luggage present on the supporting surface of the carrier,

g picking up the carrier with the buffered piece of luggage present on the supporting surface thereof from the storage position on demand, using a lift, h moving the carrier with the buffered piece of luggage present on the supporting surface thereof to a transfer station by means of the lift, i transferring the carrier with the buffered piece of luggage present on the supporting surface thereof to the transfer position of the transfer station by means of the lift,

j pushing the buffered piece of luggage off the supporting surface of a carrier positioned at the transfer position in the direction of a discharge conveying system, using moving means.

22. A method according to claim 21 , characterised in that the piece of luggage to be buffered is moved off the supply conveying system, preferably off a supply conveyor thereof.

23. A method according to claim 21 or 22, characterised in that during step b the piece of luggage to be buffered is moved to the supporting surface of the carrier at the transfer position of the transfer station via a transfer conveyor associated with a transfer station associated with at least one rack.

24. A method according to claim 21 , 22 or 23, characterised in that during step j the buffered piece of luggage is moved to the discharge conveying system via a transfer conveyor associated with the transfer station.

Description:
Title: System and method for buffering pieces of luggage DESCRIPTION

The present invention relates to a system according to the preamble of claim 1.

Such a system is known from International patent application WO 2005/002999 A1. In this system, use is made of so-called trays which carry individual pieces of luggage. Said trays carrying pieces of luggage are presented to a sorting device for subsequent storage at a storage position of a rack in the very trays in which they were presented to the sorting device. As soon as a piece of luggage must become available for transport to an aeroplane, the tray carrying the piece of luggage in question is removed from the storage position again and subsequently carried off to the plane in question on said tray. The known system is used for the temporary storage of pieces of luggage that arrive at an airport relatively long before the scheduled flight for the piece of luggage in question. An important aspect in that regard is furthermore the fact that, also from the viewpoint of labour conditions, use is increasingly made of automated or at least mechanised loading systems for loading aeroplanes, which systems can be employed more effectively if all the luggage for a particular flight can be presented to the loading system within a relatively short period, so that the loading system can be quickly utilised again for loading an aeroplane for another flight. This advantage for that matter obtains also in the situation in which an aeroplane is still loaded manually. At present luggage frequently arrives little by little at an aeroplane, as it were, so that technical facilities such as chutes and luggage carts must remain available for a relatively long period of time. These facilities are thus not used efficiently, so that a large number of such facilities are needed for loading the various aeroplanes at an airport. In the light of the foregoing there is therefore a need for temporary storage of pieces of luggage at airports and making said pieces of luggage available for being loaded on a plane in a concentrated manner. The system as described above meets that need, but it can only be used in a cost-effective manner at relatively large airports, and in that sense it has already proven its worth. For smaller airports, however, the system is relatively costly owing to the use of trays and the associated transport systems, which is why it is not used there. The object of the present invention is to provide an alternative system for buffering pieces of luggage that can also be used in a cost-effective way at relatively small airports. In order to accomplish that object, the system according to the invention is in the first place characterised in that the device comprises carriers associated with the racks, each carrier having a supporting surface for supporting individual pieces of luggage, which carriers can be moved between storage positions and a transfer position by the lift, each transfer position being arranged for receiving a carrier, and in that at least some of the transfer stations comprise moving means provided with a pusher element for each transfer station for pushing a buffered piece of luggage off the supporting surface of a carrier positioned at the transfer position. The invention is based on the inventive perception that it is advantageous to use carriers which are exclusively associated with the racks and which in that sense remain in or in any case in the immediate vicinity of said racks. The carriers are not used for extensive transport purposes through an airport, therefore, in contrast to the carriers used in the known luggage handling system. As a result, the number of carriers can remain limited, whilst in addition to that they can be of relatively simple design. In addition, no relatively complex and extensive conveying systems are needed for conveying trays that may or may not be loaded with pieces of luggage. Because of the use of the moving means, the carriers can remain associated with a rack and need not leave the direct vicinity thereof. The use of the pusher elements makes it possible in an efficient and reliable manner to push a buffered piece of luggage off the supporting surface of the carrier and onto the transfer position, after which the carrier in question becomes available for receiving a next piece of luggage to be buffered. In addition, the use of pusher elements makes it possible to use carriers of relatively simple and inexpensive design. The above aspects result in a significant cost price reduction, so that the system according to the invention can sooner be used in a cost-effective manner at relatively small airports.

In general, the available space can be used in an efficient manner if the moving means are at least partially accommodated within a rack.

In order to reduce the extent of human interference or even eliminate it altogether, it may be advantageous if the system comprises a supply conveying system for supplying pieces of luggage to be buffered to a transfer station. , .

3

Such a supply conveying system preferably comprises a supply conveyor. Such a supply conveyor may form part of a sorting device, for example. Within the framework of the invention, the supply conveying system may alternatively also comprise automatic guided vehicles (AGVs).

In order to realise a high degree of reliability in moving a luggage piece to be buffered from the supply conveyor onto the supporting surface of a carrier at the transfer position, it is preferable if the supporting surface of a carrier positioned at a transfer position is located at the same vertical level as the conveying surface of the supply conveyor.

A simple but reliable manner of transferring a piece of luggage from the supply conveyor to a transfer position can be obtained if the system comprises further moving means for moving pieces of luggage to be buffered directly present on the supply conveyor off said supply conveyor and onto or at least in the direction of the transfer position, in particular if said further moving means comprise further pusher elements for pushing pieces of luggage to be buffered directly present on the supply conveyor off the supply conveyor and onto or at least in the direction of the transfer position.

A very reliable transfer of pieces of luggage to be buffered from the supply conveyor to a transfer station can be realised if the supply conveyor is made up of a train of sorting units that can be conveyed along an endless conveying path, which sorting units each comprise a further carrier, each carrier having a further supporting surface for directly supporting an individual piece of luggage. Such sorting units are inter alia described in International patent application WO 2008/094033 A1 and in European patent application EP 2 052 682 A2.

If sorting units as described in the preceding paragraph are used, it is furthermore preferable if the aforementioned further pusher elements form part of such sorting units. Thus, each sorting unit comprises a further pusher element above the associated further supporting surface, which pusher element is laterally movable relative to the conveying path, in the direction of the transfer conveyor, at the location of the transfer conveyor for pushing a piece of luggage to be buffered off said further supporting surface and onto or at least in the direction of the transfer station. The further pusher elements may alternatively also take up a stationary position along the conveying path, which is in particular advantageous if, according to another possible embodiment, the supply conveyor is a belt conveyor. In order to reduce the extent of human interference, or even eliminate it altogether, it may be advantageous if the system comprises a discharge conveying system for discharging buffered pieces of luggage from a transfer station, wherein the moving means are designed to push a buffered piece of luggage onto or at least in the direction of the discharge conveying system.

Such a discharge conveying system preferably comprises a discharge conveyor. Such a discharge conveyor may form part of a sorting device, for example. Within the framework of the invention, the discharge conveying system may alternatively also comprise automatic guided vehicles (AGVs).

In order to realise a high degree of reliability in moving a buffered piece of luggage off a supporting surface of a carrier and onto the discharge conveyor at the transfer position, it is preferable if the supporting surface of a carrier positioned at a transfer position is located at the same vertical level as the conveying surface of the discharge conveyor.

With a view to (further) reducing the amount of hardware of which the system is built up, and thus the cost of such a system, it is advantageous if the discharge conveyor and the supply conveyor are made up of a common conveyor.

In order to obtain some buffering capacity for each transfer station for those situations in which a lift is not directly available for picking up a piece of luggage to be buffered from a transfer location, it is preferable if at least some of the transfer stations are provided with at least one transfer conveyor for conveying a piece of luggage to be buffered from the supply conveying system to the transfer position of the transfer station in question and/or for conveying a buffered piece of luggage from the transfer position of a transfer station to the discharge conveying system. If a supply conveyor is used, the transfer conveyors can branch off the supply conveyor, as it were.

With a view to reducing the amount of hardware of which the system is built up, and thus the cost of such a system, it is advantageous if the discharge conveyors can be driven in two opposite directions for conveying a piece of luggage to be buffered from the supply conveying system to an unloaded carrier at a transfer position of the transfer station in question and for conveying a buffered piece of luggage from a carrier at a transfer position of the transfer station in question to the discharge conveying system.

The transfer conveyor is preferably a belt conveyor.

With a view to achieving constructional simplicity, and thus a relatively low cost price, it is preferable if the carriers are at least substantially plate- shaped.

The carriers preferably have a flat or a slightly concave upper side forming the supporting surface. Thus it is possible in a simple manner to move pieces of luggage in horizontal direction onto the supporting surface of a carrier.

The present invention further provides a method for buffering pieces of luggage, using a system according to the invention as described in the foregoing. The method comprises the successive steps recited in claim 21.

For reasons already explained in the foregoing, it may be very advantageous if the piece of luggage to be buffered is moved off the supply conveying system, preferably off a supply conveyor thereof, during step b and/or if the buffered piece of luggage is pushed off the carrier during step j.

With regard to step b it obtains that, furthermore preferably, the piece of luggage to be buffered is moved to the supporting surface of the carrier at the transfer position of the transfer station via a transfer conveyor associated with a transfer station associated with at least one rack during step b.

With regard to step j it obtains that preferably the buffered piece of luggage is moved off the carrier, which can be realised in a very reliable manner, using relatively simple means.

With regard to step j it obtains that, furthermore preferably, the buffered piece of luggage is moved to the discharge conveying system via a transfer conveyor associated with the transfer station.

The invention will now be explained in more detail by means of a description of possible embodiments of the present invention, in which reference is made to the following schematic figures:

Figure 1 is a top plan view of a system according to the invention;

Figure 2 is a side view, along the line ll-ll in figure 1 , of a system according to figure 1 ;

Figure 3 is a top plan view of an alternative embodiment of a system according to the invention. Figures 1 and 2 schematically show in two different, perpendicular views a system 1 for buffering pieces of luggage 2 (only shown in figure 2). At airports pieces of luggage, such as suitcases, bags, rucksacks and the like frequently arrive at the airport relatively well in advance of the departure time of the flight associated with the respective piece of luggage. In that case there is a need for temporary storage of the pieces of luggage in question, in which case it must be possible, of course, to make the pieces of luggage in question available in time when the departure time of the flight in question draws near. The system 1 provides for that need.

The system 1 comprises a number of racks 3 arranged parallel to each other. Each rack comprises storage positions 4 arranged in a regular pattern beside and above each other. Each storage position 4 is suitable for temporary storage of an individual piece of luggage 2.

Between the racks 3, the system 1 comprises lifts 5, which can each be moved forward and backward along paths of movement 6 between the racks 3 in question, as indicated by the double arrow 7.

The system 1 further comprises a sorting device 10, which forms part of a conveying system both for supplying pieces of luggage 2 to be buffered to the racks 3 and for discharging buffered pieces of luggage from the racks 3. For a detailed description of the sorting device 10, reference is made to International patent application WO 2008/094033 A1. Within the framework of the present invention, it suffices to say that the sorting device 10 is provided with a main conveyor 1 1 made up of an endless train of sorting units 13 which can be conveyed along an endless conveying path 12. The successive sorting units 13 are pivotally interconnected about vertical pivot axes, so that the train can pass through bends. Each sorting unit 13 has a carrier 14, for example configured as a flat plate, with a supporting surface 15 for supporting an individual piece of luggage 2 present at the upper side thereof. Each sorting unit 13 further comprises, just above the supporting surface 15, a pusher beam 16 which can be moved forward and backward along the associated supporting surface 15, between the two positions shown in figure 1 for the various sorting units 13, as indicated by the arrows 17, 18. A piece of luggage 2 present on a supporting surface 15 that might lie in the path of the pusher beam 16, will be pushed off the supporting surface 15, in the direction indicated by the respective arrow 17, 18, by the pusher beam 16. The endless conveying path 12 comprises two opposing, parallel, straight sections 19, 20 and two opposing 180 degree bends 21 , 22 connecting the straight sections 19, 20. The exact form of the endless conveying path 12 is not essential within the framework of the invention. Thus, the endless conveying path will usually comprise at least four 90 degree bends in practice. The racks 3 are provided on the outer side of the endless conveying path 12, their longitudinal direction extending perpendicularly to the straight section 19 of the conveying path.

Between each rack 3 and the straight conveying path section 19, the system 1 comprises a transfer station 30. Seen from the straight conveying path section 19, each transfer stations 30 comprises a belt conveyor 31 , a transfer position 32 and a pusher element 33 which may, at least substantially so, be configured as a pusher beam 16. The pusher element 33, together with driving means 34 provided for moving the pusher element 33 forward and backward in horizontal direction, takes up the space of a storage position 4 of the associated rack 3, which storage position is thus not available for the storage of an individual piece of luggage 2 (see figure 2). The belt conveyor 31 can be driven in two directions as indicated by the double arrow 35. The transfer position 32 in fact consists, at least substantially so, of a number of girders 36 extending parallel to each other in horizontal direction, parallel to the straight section 19. The upper sides of the girders 36 are located below the level of the upper side of the belt conveyor 31 , being spaced therefrom by a distance X.

The buffer system 1 further comprises carriers configured as slightly concave boards 40, which in fact may be configured as planks, for example. The height/thickness of said boards 40 approximately equals the distance X. In principle a board 40 is provided for each storage position. The boards 40, on which a piece of luggage 2 may or may not be present, can be moved up and down by means of a lift 5 between a transfer position 32 and a storage position 4. In figure 2 a board 40' with a piece of luggage 2' present thereon is illustrated in broken lines at the transfer position 32.

The lift 5 is provided with a lift element 41 for moving the board 40, which lift element can be moved up and down along columns 43 of the lift 5 as indicated by the double arrow 42. Each lift element comprises arms (not shown) which are known per se, which arms can be moved out from under a board 40, whereupon the board 40 in question, on which a piece of luggage 2 may be present, can be picked up by the lift element 41 by moving the lift element 41 slightly upwards. At the transfer position 32, the arms project between the girders 36. The arms of each lift element 41 can be extended in two different opposite directions, so that all storage positions 4 associated with the two racks 3 between which the lift 5 can move, as well as the two transfer positions 32 of the two associated transfer stations 30, are within reach of the lift 5.

The buffer system 1 can be used as follows: a piece of luggage 2 to be buffered is supplied to a sorting unit 13 of the sorting device 10 by means of a supply conveyor 51. The piece of luggage 2 to be buffered, lying on the flat board 14 of the sorting unit 2 three, is conveyed along the endless conveying path 12, past the various transfer stations 30, by the main conveyor 1 1 . The pusher beam 16, controlled by the control system of the system 1 , is located on the inner side of the endless conveying path 12, as is for example shown in figure 1 for the sorting unit 13, in this case the second sorting unit 13.

The control system of the system 1 has reserved a storage position

4 for the piece of luggage 2 to be buffered, and at the transfer station 30 associated with the rack 3 of which the storage position 4 forms part, the pusher beam 16 of the sorting unit 13 on which the piece of luggage 2 to be buffered is present is controlled to move in the direction indicated by the arrow 18. During said movement, the piece of luggage to be buffered is pushed onto the belt conveyor 31 of the transfer station 30 in question. It is noted in this regard that, as is shown in figure 2, the supporting surface 15 of the carrier 14 of the sorting unit 13 in question and the upper side of the belt conveyor 31 lie at the same vertical level, so that the transfer of the piece of luggage 2 to be buffered from the main conveyor 1 1 to the belt conveyor 13 can take place smoothly. The belt conveyor 31 conveys the piece of luggage 2 to be buffered onward, to the right in figure 2, so that it is moved onto an empty board 40 supported by the girders 36 of the transfer position 32. Said board 40 with the piece of luggage 2 to be buffered present thereon is subsequently picked up by the lift element 41 , whereupon the lift 5 moves to a position in which the lift 5 is positioned opposite the reserved storage position, to the right in figure 2. Said reserved storage position is indicated at 4' in figure 2. Simultaneously therewith, or subsequently, the lift element 41 moves upward until the lift element 41 is positioned directly opposite the reserved storage position A'. Each storage position 4 is provided with supports on which the board 40 can be supported, which supports are not shown but which are known to those skilled in the art. The board 40 with the piece of luggage 2 to be buffered present thereon is moved in the direction of the storage position 4' by extending the arms of the lift element 41. The lift element 41 is in that situation positioned at a height such that the underside of the board 40 extends just above the supports associated with the storage position 4'. By slightly lowering the lift element 41 after the arms of the lift element 41 have been extended, the board 40 with the piece of luggage 2 to be buffered present thereon is taken over by the rack 3 at the storage position 4 in question. The arms of the lift element 41 are now retracted again. Following that, the lift 5 can move the lift element 41 to a storage position 4 where and unloaded board 40 (one of which is indicated at 40" in figure 2) is stored. The loaded board 4 in question, or the unloaded board 40", is picked up by the lift element 41 in a manner which, based on the foregoing, will be obvious to the skilled person, and delivered at the storage position 32. The unloaded board 40" is subsequently available for receiving a next piece of luggage 2 to be buffered from the main conveyor 1 1 , in a manner as described in the foregoing.

After the arms of the lift element 41 have been retracted as described above, the lift 5 can also move the lift element 41 to a storage position where a loaded board 40 is stored if the piece of luggage 2 present on the board 40 in question must be made available, as will in particular because if the time of the flight for the piece of luggage 2 in question is approaching. The board 40 carrying the buffered piece of luggage 2 in question is then removed from the rack 3 in question by means of the lift 5 and taken to the transfer position 32. At said transfer position, the pusher element 33 pushes the buffered piece of luggage 2 off the board 40 onto the belt conveyor 31 , which conveys the buffered piece of luggage 2 onward to the left, seen in figure 2, so as to move it on onto and unloaded carrier 14 of a passing sorting unit 13. The control system of the buffer system 1 ensures that the pusher beam 16 of the sorting unit 13 in question is located on the inner side of the endless conveying path 12. The main conveyor 11 then conveys the buffered piece of luggage 2 further along the endless conveying path 12. As soon as the sorting unit 13 passes the discharge conveyor 52, the pusher beam 16 is activated to move in the direction indicated by the arrow 18 toward the outer side of the endless conveying path 12, during which movement the buffered piece of luggage 2 is pushed off the carrier 14 and onto the discharge conveyor 52. The discharge conveyor 52 forms part of a conveying system, via which the buffered piece of luggage 2 is conveyed to the aeroplane for the flight in question.

Figure 3 shows an alternative system 61 according to the invention. The buffer system 61 is essentially only different from the buffer system 1 shown in figures 1 and 2 as regards the configuration of the sorting device. As it is, the buffer system 61 comprises a sorting device 62 having a main conveyor 63 configured as a belt conveyor. A number of stationary pusher elements 64 are provided along the belt conveyor 63, directly opposite each transfer station 30 on the other side of the belt conveyor 63. By activating a pusher element 64 during the passage of a piece of luggage to be buffered present on the belt conveyor 62, the respective piece of luggage 2 to be buffered can be transferred to a transfer station 30. For the rest the operation of the buffer system 61 is quite similar to that of the buffer system 1.

Both systems shown in figures 1-3 make use of a main conveyor 11 , via which the supply of pieces of luggage to be buffered as well as the discharge of buffered pieces of luggage takes place. Alternatively it is also possible to make use of a separate supply conveyor and a separate discharge conveyor. The discharge conveyor might in that case be positioned at the opposite ends of the racks 3, or at a different vertical level than the supply conveyor. In another alternative embodiment, no use is made of a conveyor for supplying and discharging pieces of luggage, instead of that automatic guided vehicles (AGVs) are used.