TRAY, STACK OF TRAYS AND METHODS FOR LOADING / UNLOADING TRAYS

Description

[0001] The present invention relates to a tray for storing and / or transporting goods, in particular plastic containers, a stack with several trays, a method for loading trays with goods and a method for unloading goods from trays.

[0002] For storage and transport, goods are often loaded into storage and transport containers, so-called trays. Loading of the trays takes place, for example, in semi- or fully automated loading and unloading systems, which can be located downstream of a production facility, such as a blow molding machine for plastic containers, or upstream of a filling station.

[0003] It's well known that available storage space is a valuable commodity, and therefore should be utilized as efficiently as possible. It's also important to store stored goods securely and, for example, to protect them from tipping over or excessive movement during transport. If the goods are packed relatively loosely, for example, they can be moved around considerably and rub against each other. This can lead to scratches on the surface of the goods.

[0004] If the goods are to be packed, or at least packed in an orderly manner, more or less complicated devices may be necessary to place the goods into corresponding trays. One such device is known, for example, from WO 2017 / 174420 A1. Although the device disclosed in this PCT application simplifies the previously known methods and devices for loading goods into trays and also prevents the individual goods from falling over during the loading process, the device nevertheless comprises a relatively large number of individual parts. Another device for loading / unloading trays is known from DE 10230524 A1. A tray according to the preamble of independent claim 1 is known from US 2700485 A.

[0005] It is therefore an object of the invention to remedy at least one or more disadvantages of the prior art. In particular, a tray is to be created that allows it to be loaded using simple means, and in particular, with a high packing density. Preferably, a corresponding loading and unloading method is to be provided.

[0006] This object is achieved by the devices and methods defined in the independent patent claims. Further embodiments are set forth in the dependent patent claims.

[0007] A tray according to the invention for storing and / or transporting goods, in particular plastic containers, comprises two first side walls and two second side walls. The tray also comprises four corner elements, the first and second side walls being connected to the corner elements via plug-in connections. The tray has a movable base.

[0008] A movable base allows the tray to be loaded with goods at a higher packing density. The movable base can be raised so that its vertical position is shifted relative to the side walls, thus improving accessibility. Preferably, the movable base is shifted at least to an upper end of the side walls, in particular beyond an upper end of the side walls. Goods placed on the raised base can, for example, be grasped laterally with a corresponding device, such as a gripping unit, without interference between the device and the side walls.

[0009] Free space within the fully loaded tray between the side walls and the goods for a corresponding gripping unit is therefore no longer necessary, neither for loading the goods nor for unloading them. The goods can be placed directly on the raised base or removed from it. Dropping of the goods to be loaded due to insufficient space within the tray for the gripping unit can be avoided. The goods to be loaded can therefore be placed into the tray essentially without impact. After the goods to be loaded have been placed on the raised base, the base can be lowered again. The goods placed on the raised base are lowered accordingly together with the base and are located within the tray after lowering.

[0010] The unloading process is also simplified and can be carried out more gently. Typically, trays that lack additional space for a gripping unit must be tipped. The goods in the tray experience numerous impacts and can therefore be scratched.

[0011] The movable floor, on the other hand, allows the floor to be raised along with the goods, making them accessible from the outside and allowing them to be lifted from the raised floor using a suitable gripping unit. The goods therefore no longer need to be poured, but can be grasped and repositioned.

[0012] The gripping unit can be designed as a particularly rectangular frame, which has movable side walls that can be advanced towards a center of the gripping unit.

[0013] The movable, adjustable side walls allow the clear cross-section within the frame to be reduced or increased. This allows the frame to be positioned with a relatively large clearance above the goods to be loaded and to be lowered to a final position without interference with the goods. The movable side walls can then be adjusted accordingly toward the goods, ensuring they are held securely. A slight compression can be provided to enforce this.

[0014] The tray may have at least two cross members, wherein two opposite side walls are connected to the at least two cross members.

[0015] The crossbeams increase the stability of the side walls. The first and second side walls, together with the four corner elements, form a frame in which the movable floor is located. This frame can be stabilized by connecting two opposite side walls with at least two crossbeams.

[0016] Preferably, the movable floor rests on the crossbeams. The movable floor is thus stabilized and held in place by the crossbeams. Accordingly, extensive equipment for increasing the stability and / or rigidity of the movable floor itself can be dispensed with, as this can be handled by the corresponding crossbeams.

[0017] Nevertheless, it is possible and conceivable that the movable floor has projections on its periphery to increase stability.

[0018] These projections can be created by bevels or folds. Multiple folds are also possible.

[0019] The movable base can be made of a metallic material, such as steel or aluminum and / or alloys thereof. The movable base can be formed from sheet metal, with the edges at its periphery being able to be beveled.

[0020] The tray can be designed such that the projections of the movable base engage or can be brought into engagement with corresponding recesses on the at least two cross members, so that the movable base can be positioned in the tray.

[0021] The movable base can thus be held in a defined position within the tray and uncontrolled movement can be prevented.

[0022] Such a design also increases the stability of the tray.

[0023] To fix the first and / or second side walls, the plug connections are deformed or deformable.

[0024] After the connectors have been joined together, they can be deformed accordingly to prevent them from becoming accidentally loose.

[0025] The plug-in connections themselves allow the side walls to be connected to the corner elements easily and without tools.

[0026] The side walls can be made of a metallic material, such as steel or aluminum and / or alloys thereof. Preferably, the side walls are made of sheet metal. The sheet metal or the side walls can have bevels or folds to increase stability.

[0027] Recesses can be provided on the cross members which, when stacking several trays, can be brought into engagement with the first side walls of a second tray arranged below a first tray.

[0028] When stacking trays, they can be positioned next to each other to create a stable stack of several trays.

[0029] The second side walls of the tray can have a support element and a support, so that when stacking several trays, the support element of a second side wall of a first tray can be arranged on the support of a second side wall of a second tray.

[0030] This enables the safe and precise stacking of several trays on top of each other.

[0031] The support element can have conical guide surfaces for centering purposes.

[0032] This facilitates the insertion or stacking of trays and improves positioning. Accordingly, the support may have one or more substantially complementary surfaces that can be brought into engagement or operative connection with the conically tapered guide surfaces.

[0033] It goes without saying that corresponding supports and support elements can also be provided on the first side walls.

[0034] A further aspect of the invention relates to a stack comprising a plurality of trays, in particular a plurality of trays as described herein. The stack is arranged on a frame. The frame engages with the recesses of the cross members of a lowermost tray.

[0035] Providing a stack on a separate frame allows for easy shifting, aligning, and moving of the corresponding stack.

[0036] Additionally or alternatively, it can be provided that the frame engages with support elements of the second side walls of a lowermost tray.

[0037] The frame's engagement with the recesses of the cross members and / or the support elements of the second side walls allows for precise positioning of the stack of trays arranged on the frame. This creates a secure and reliable connection between the frame and the stack of trays.

[0038] The frame can be made of a metallic material, particularly stainless steel. This provides great strength and prevents excessive wear.

[0039] The stack may have a lid, wherein the lid rests on corresponding supports of the second side walls of an uppermost tray.

[0040] The stack of trays is thus sealed and the ingress of dirt can be prevented.

[0041] It goes without saying that the lid can also be applied to individual trays and that a stack of trays does not necessarily have to be present.

[0042] As described for the second side walls of the tray, the first side walls can also have corresponding support elements and supports.

[0043] Depending on the arrangement of the cross members, their recesses cannot be connected to the first side walls of a tray, but rather to second side walls.

[0044] A further aspect of the invention relates to a method for loading trays as described herein with goods. The goods are preferably plastic containers. The method comprises the steps Providing a stack of trays, in particular a stack as described here, removing a first tray from the stack, providing this tray in a loading position, raising the movable base of the tray up to a loading level, placing the goods to be loaded on the raised base, lowering the raised base into its original position.

[0045] As already explained, this method allows a tray to be loaded with goods without having to drop them unnecessarily from a great height. Furthermore, this method allows a tray to be packed more densely, as no additional space is required within the tray for, for example, reaching into the tray with a gripper unit.

[0046] Preferably, the movable base is raised vertically above the side walls of the tray.

[0047] Once raised, the movable floor is positioned above the side walls and is fully accessible from the side. The goods to be loaded can thus be pushed directly onto the raised floor from the side and do not necessarily need to be lifted to be placed on the movable floor of the tray.

[0048] The goods to be loaded are preferably placed on the movable base of the tray using a gripper unit. This allows for precise and accurate loading of the goods into the tray.

[0049] It can be provided that the gripping unit carries out a complete loading of the tray in a single step, in other words, places all goods to be loaded simultaneously and in one step on the movable base of the tray.

[0050] The gripping unit can be designed essentially as a rectangular frame that encloses a packing area containing goods to be loaded and pushes this packing area onto the raised, movable floor. The packing area can be held firmly in place by movable side walls of the frame without clamping. Alternatively, it is also possible for the movable side walls to exert a slight pressure on the goods to be loaded.

[0051] Preferably, after placing the goods to be loaded, the gripping unit is opened or at least relieved to such an extent that the goods to be loaded are no longer clamped. The gripping unit remains in this position for at least part of the lowering process of the movable floor.

[0052] By keeping the gripping unit in this position, lateral guidance is provided during the lowering process so that the goods placed on the movable floor cannot fall over.

[0053] After the loading process, the tray can be fed into a second stack of loaded trays.

[0054] Preferably, before placing the goods to be loaded on the raised floor, the goods to be loaded are provided in a collection position, in particular as a packing field.

[0055] A packing area corresponds to the number of goods to be loaded, which corresponds to the maximum number of goods that can be placed in a single tray. A packing area is also designed according to the size of the tray, i.e., its length and width correspond to the respective dimensions of the tray to be loaded.

[0056] This allows the provision of a complete layer of goods which are placed in the tray or on the raised floor.

[0057] Preferably, a plurality of goods are transferred from a feed device into the collection position by means of a transfer device, in particular a gripper or a pusher.

[0058] By appropriately moving the goods, a complete layer of goods can be made available so that they can be moved by a corresponding gripping unit and placed on the raised floor.

[0059] The plurality of goods may be arranged in at least one row and preferably in several rows.

[0060] Arranging goods in one or more rows, or providing them in one or more rows, allows for easy transfer of the corresponding goods, for example, onto an indexing belt with a centering frame. The indexing belt allows individual or multiple rows to be moved together in a specific direction and aligned with a centering frame, or aligned with already positioned goods.

[0061] Once a sufficient number of goods to be loaded are positioned on this centering frame, they can be measured automatically. This measurement determines whether the resulting packing area has the desired external dimensions. If this is the case, the centering frame can be removed and the entire packing area moved to the collection position.

[0062] The transfer device can be designed as a gripper, in particular as a multi-gripper, as described, for example, in WO 2017 / 174420 A1. A multi-gripper is a gripper that can grip multiple containers simultaneously.

[0063] Alternatively, the transfer device can also be designed as a simple pusher, which allows the goods to be loaded to be pushed sideways onto a timing belt.

[0064] Another aspect of the invention relates to a method for unloading goods from trays as described herein. The goods are preferably plastic containers. The method comprises the following steps: Providing a stack of loaded trays, in particular a stack as described here, removing a first tray from the stack, providing this tray in an unloading position, raising the movable base of the tray up to an unloading level so that the goods to be unloaded placed on the base are raised, removing the goods to be unloaded from the raised base, lowering the raised base into its original position.

[0065] Raising the movable base for removing goods allows the goods to be raised relative to the side walls of the tray, allowing them to protrude beyond the edge of the tray. This allows the goods to be accessed from the side and removed using appropriate devices without requiring additional space within the tray.

[0066] The goods can be removed, for example, using a gripping unit. The gripping unit can be designed as described here, for example, as a substantially rectangular frame.

[0067] Preferably, the movable base is raised vertically above the side walls of the tray.

[0068] By raising the floor above the side walls, the goods arranged or placed on the floor are fully accessible from the side. To remove them from the tray, and in this case, from the bottom of the tray, the goods can simply be moved sideways. Vertical lifting is no longer necessary.

[0069] Preferably, the goods to be unloaded are removed from the movable floor using a gripping unit and placed in a ready position.

[0070] In this standby position, the unloaded goods can be separated or further processed in groups, such as in individual rows, or positioned for further processing.

[0071] To remove the goods to be unloaded from the raised floor, the gripping unit is closed so that the goods to be unloaded are clamped or held firmly in the gripping unit. The gripping unit can remain in this position for at least part of the lowering process.

[0072] If the gripping unit is designed as a substantially rectangular frame, it can have movable side walls that allow the frame's clear cross-section to be enlarged or reduced. The goods to be unloaded can be held firmly by the frame's movable side walls without clamping. Alternatively, the movable side walls can also exert a slight pressure on the goods to be unloaded.

[0073] It is also conceivable that before the floor is lifted, the gripping unit moves into a corresponding removal position and remains in the open state, so that while the floor is lifted, the gripping unit forms a lateral guide for the goods lifted with the floor.

[0074] Accordingly, they are protected against falling over during the lifting process.

[0075] After the unloading process, the tray can be fed into a second stack of unloaded trays. Multiple trays can be easily stacked into a single stack, so they can be fed back into a loading device together.

[0076] Following the unloading process, a plurality of goods can be transferred from the standby position to a conveyor belt by means of a transfer device, in particular a gripper or a pusher.

[0077] The goods can be fed to a further processing device, such as a filling system, via a conveyor belt.

[0078] The plurality of goods may be arranged in at least one row and preferably in several rows.

[0079] This allows goods to be processed line by line from the standby position.

[0080] Embodiments of the present invention are explained in detail below with reference to figures that are merely schematic representations. They show: Figure 1: a stack of trays; Figure 2: a single tray; Figure 3: a sectional view through the bottom tray from the Figure 1 ; Figure 4: a detailed view of a cross member; Figure 5: a sectional view through a single tray according to the Figure 2 ; Figure 6: another sectional view through the bottom tray of the stack according to the Figure 1 ; Figure 7: a sectional view through the stack according to the Figure 1 ; Figure 8: a perspective view of a loading station; Figure 9: a top view of the loading station according to the Figure 8 ; Figure 10: a perspective detailed view of the loading station according to the Figure 8 ; Figure 11: a side view of the loading station according to the Figure 8 ; Figure 12: a side view of an alternative loading station.

[0081] Figure 1 shows a stack 30 of trays 20. The stack 30 of trays 20 has a lid 32, with which the uppermost of the three trays 20 is closed. The lowest of these three trays 20 stands on a frame 31. The trays 20 have first side walls 22 and second side walls 23. The side walls 22 and 23 are connected to one another via corner elements 24. For the sake of clarity, not all identical parts are provided with reference numerals.

[0082] The Figure 2shows a single tray 20 in a perspective view. The tray 20 has two first side walls 22 and two second side walls 23. The first side walls 22 are arranged opposite one another. The second side walls 23 are also arranged opposite one another. Each first side wall 22 is connected to a second side wall 23 via a corner element 24. The four side walls 22 and 23, together with the four corner elements 24, form a frame. A movable base 26 is arranged within this frame.

[0083] The Figure 3 shows a sectional view through the bottom tray 20 from the Figure 1 The sectional view extends essentially parallel to the second side wall 23. This sectional view shows the cross member 21, which is located below the movable base 26. The base 26 rests on the cross member 21. Also visible is a frame 31 on which the tray 20 is arranged.

[0084] The base 26 is formed from a sheet metal and has projections 261 on its periphery. These serve, on the one hand, to increase stability and, on the other hand, to position the base 26 within the tray 20.

[0085] The projections 261 are formed in this case by repeatedly bending the sheet metal.

[0086] The projections 261 engage in corresponding recesses 211 on the cross member 21.

[0087] It goes without saying that the design of the base 26 explained here, in particular its projections, can run along the entire periphery of the base 26.

[0088] The end of the cross member 21 is snapped into corresponding recesses in the side wall 22.

[0089] The side wall 22 is connected to the side wall 23 via the corner element 24. Plug connections 25 are arranged on the corner element 24 and engage in corresponding openings on the side walls 22 and 23. These plug connections 25 can be deformed if necessary, so that the connection between the side walls 22 or 23 and the corner element 24 can no longer be broken. Additionally, an opening can be provided in the corner element 24, into which a corresponding counterpart of the side walls 22 or 23 can be bent. An exemplary arrangement is shown in the Figure 5 shown. In this, a counterpart 234, designed as a deformable tongue, is bent into an opening 241. Vertical displacement of the corner element 24 and the side wall 23 relative to each other is prevented.

[0090] In the Figure 3It is also evident that the frame 31 is formed as a bent molded part and has two cheeks. One of the two cheeks engages in a recess 212 on the cross member 21.

[0091] The Figure 4 shows a detailed view of a cross member 21 and, in this case, a first end of the cross member 31. The cross member 21 is formed as a bent molded part made of sheet metal. Visible here are the recess 212 and the cutouts 211 for receiving the projections 261 of the base 26 (see Figure 3 ). The recesses 213 and 214 are provided for engagement in corresponding recesses or counter surfaces on the side wall 22 in order to snap the cross member 21 into the side wall 22.

[0092] The Figure 5 shows a sectional view through a single tray 20 according to the Figure 2 . In the Figure 5The corner element 24 is also visible, with an opening 241 arranged thereon into which a counterpart 234 of the side wall 23 is bent. This prevents vertical displacement of the side wall 23 and the corner element 24 relative to each other.

[0093] The cut of the Figure 5 extends through the side wall 23. The side wall 23 has a support element 231 at its lower end shown here, which is also at the bottom in typical use. The support element 231 extends along the side wall 23. Guide surfaces 233 extend on both sides of the support element 231. The guide surfaces 232 have an inclination to the horizontal, so that the guide surfaces 233 are directed towards one another.

[0094] The side wall 23 has a support 233 at its upper end shown here, which is also at the top in typical use. The support 233 extends along the side wall 23. On one side of the support 232, in this case toward the interior of the tray 20, extends a guide surface (not further designated). This guide surface has an outwardly directed inclination relative to the horizontal.

[0095] The Figure 6 shows a further sectional view through the bottom tray 20 of the stack 30 according to the Figure 1. This tray 20 is arranged on a frame 31. In particular, the tray 20 stands on the frame 31 with a support element 231. A guide surface 233 is in contact with the frame 31, and in this case with a substantially correspondingly arranged surface on the frame 31. This corresponding surface is provided by a corresponding fold on the frame 31. A corresponding formation is found on all four side walls 22, 23 of the tray 20 (see the Figure 2 ). Accordingly, the tray 20 is centered when it is arranged on a frame 31.

[0096] The Figure 7 shows a sectional view through the stack 30 according to the Figure 1. In particular, the sectional view is shown through the interface between two stacked trays 20. A first, upper tray 20 stands on a second, lower tray 20. The support element 231 of a side wall 23 of the upper tray stands on a corresponding support 232 of a side wall 23 of the lower tray 20. A guide surface 233 of the side wall 23 is in engagement with a corresponding, unspecified, guide surface on the support 232 of the side wall 23. A corresponding formation is found on all four side walls 22, 23 of the tray 20 (see the Figure 2 ). Accordingly, the trays 20 are centered relative to each other when they are stacked into a stack 30.

[0097] The Figure 8shows a perspective view of a loading station for loading trays 20 with goods. A stack 30 of trays 20 and a stack 30' of loaded trays 20' are visible in the loading station. In the loading stream upstream of the stack 30, a gripping unit 40 and a transfer device 50, which in this case is designed as a gripper, are visible. The feed device 60 is shown leading into the loading station.

[0098] The Figure 9 shows a top view of the loading station according to the Figure 8The goods to be loaded are introduced into the loading station via the feed device 60, specifically into the area below a transfer device 50. The transfer device 50 grips the goods to be loaded row by row, in this case as a double row ZZ, and conveys them onto a not-further-designated indexing belt. The indexing belt transfers this double row ZZ of goods to be loaded along the loading stream toward a packing area P that is in the collection position S. The gripping unit 40 then places the packing area P accordingly onto a raised base of a tray.

[0099] The Figure 10 shows a perspective detailed view of the loading station according to the Figure 8 . This illustration shows that a tray 20 to be loaded is arranged in a lower vertical plane than the unspecified timing belt on which the packing field P is arranged.

[0100] The tray's movable base can be raised to a loading level. In this case, this level is level with the indexing belt.

[0101] Above the tray 20, the gripping unit 40 is shown, which clamps another packing field and places it on a corresponding base 26 (see Figure 2 ) pushes.

[0102] The Figure 11 shows a side view of the loading station according to the Figure 8 . In the Figure 11 The lifting unit 80 is visible, with which the base 26 of the tray 20 is raised. The lifting unit 80 has several motor-driven, hydraulic or pneumatic cylinders that raise the base 26. The base 26 is raised until it is essentially in the same plane as the unspecified indexing belt. This allows the packing field P to be placed on the base 26 essentially by a horizontal displacement.

[0103] The Figure 12shows a side view of an alternative loading station. This is designed in such a way that the tray loading process is divided into further steps.

[0104] The goods to be loaded are introduced into the loading station via the feed device 60, specifically into the area next to a transfer device 50. The feed device 60 is designed such that two rows of goods to be loaded can be introduced into the loading station simultaneously. The transfer device 50 is designed as a pusher that pushes the goods to be loaded laterally onto a timing belt in the form of a double row ZZ. This double row ZZ is then moved toward a run-up centering frame 61 until it runs onto the run-up centering frame 61, or onto an already existing double row ZZ of goods to be loaded. As soon as a corresponding number of goods to be loaded have run onto the run-up centering frame 61, the dimensions of the goods to be loaded are measured. If this corresponds to a specified size, the run-up centering frame 61 is removed and the packing area is moved toward a collection position S.

[0105] In the collecting position S, the packing field P is enclosed by the gripping unit 40 and moved laterally onto a raised base 26 of a tray 30, so that the packing field P together with the gripping unit 40 is in the Figure 12 shown location.

[0106] In the Figure 12 A transfer device 50 is shown, which is designed as a slide. It is understood that a transfer device as shown in the Figures 8 to 11 The transfer device 50 shown in the drawing, which is designed as a gripper, can be used. It is also possible to use the Figure 12 shown slider in the loading station according to the Figures 8 to 11 to apply.

Claims

1. A tray (20) for storing and / or transporting goods, in particular plastic containers (10), comprising two first side walls (22) and two second side walls (23) and four corner elements (24), wherein the side walls (22, 23) are connected to the corner elements (24) via plug connections (25), characterized in that the tray (20) has a movable base (26).

2. The tray (20) according to claim 1, characterized in that the tray (20) has at least two crossmembers (21), wherein two opposing side walls (22, 23) are connected to the at least two crossmembers (21).

3. The tray (20) according to claim 2, characterized in that the movable base (26) rests on the crossmembers (21).

4. The tray (20) according to one of claims 1 to 3, characterized in that the movable base (26) has projections (261) on its periphery for increasing the stability.

5. The tray (20) according to claim 4, characterized in that the projections (261) can engage or be brought into engagement in corresponding recesses (211) in the at least two crossmembers (21) so that the movable base (26) can be positioned in the tray (20).

6. The tray (20) according to any of claims 1 to 5, characterized in that the plug connections (25) are deformable or deformed for fixing the first and / or second side walls (22, 23).

7. The tray (20) according to one of claims 1 to 6, characterized in that recesses (212) are provided in the crossmembers (21) that can brought into engagement with the first side walls (22) of a second tray (20) arranged below a first tray (20) during the stacking of a plurality of trays (20).

8. The tray (20) according to any of claims 1 to 7, characterized in that the second side walls (23) of the tray (20) have a support element (231) and a support (232) so that the support element (231) of a second side wall (23) of a first tray (20) is arrangeable on the support (232) of a second side wall (23) of a second tray (20) during the stacking of a plurality of trays (20).

9. The tray (20) according to claim 8, characterized in that the support element (231) has guide surfaces (233) tapering conically to one another for centering.

10. A stack (30) having a plurality of trays (20) according to any of claims 7 to 9, characterized in that the stack (30) is arranged on a frame (31), wherein the frame (31) is engaged with the recesses (212) of the crossmembers (21) of a bottommost tray (20).

11. The stack (30) having a plurality of trays (20) according to any of claims 8 to 9, characterized in that the stack (30) is arranged on a frame (31), wherein the frame (31) is engaged with the support elements (231) of the second side walls (23) of a bottommost tray (20).

12. The stack (30) according to any of claims 10 or 11, characterized in that the stack (30) has a cover (32), wherein the cover (32) rests on corresponding supports (232) of the second side walls (23) of an uppermost tray (20).

13. A method for loading trays (20) according to any of claims 1 to 9 with goods, comprising the steps of: - providing a stack (30) of trays (20), in particular a stack (30) according to any of claims 10 to 12, - removing a first tray (20) from the stack (30), - providing this tray (20) in a loading position, characterized by the steps of: - raising the movable base (26) of the tray (20) up to a loading level, - placing the goods to be loaded on the raised base (26), - lowering the raised base (26) into its original position.

14. A method for unloading goods from trays (20) according to any of claims 1 to 9, comprising the steps of: - providing a stack (30') of loaded trays (20'), in particular a stack (30') according to one of the claims 10 to 12, - removing a first tray (20') from the stack (30'), - providing this tray (20') in an unloading position, characterized by the steps of - lifting the movable base (26) of the tray (20') up to an unloading plane so that the goods placed on the base (26) to be unloaded are lifted, - removing the goods to be unloaded from the raised base (26), - lowering the raised base (26) into its original position.