WO2025051545A1

WO2025051545A1 - Storage system, floor element, and method

Info

Publication number: WO2025051545A1
Application number: PCT/EP2024/073506
Authority: WO
Inventors: Geir Vikingstad; Kjell Tore KLUNGLAND; Martin Diekmann; Kenneth MÜLLER; Trond Austrheim; Martin FITJE
Original assignee: Autostore Technology AS
Priority date: 2023-09-08
Filing date: 2024-08-21
Publication date: 2025-03-13
Also published as: NO348595B1; NO20230959A1

Abstract

The present disclosure provides a storage system for storage containers, the storage system comprising a framework structure having a rail grid configured to allow a container handling vehicle to move thereon, the framework structure defining a plurality of storage columns below the rail grid, in which storage columns storage containers are arranged one on top of another in vertical stacks; the rail grid comprises a first set of parallel rails and a second set of parallel rails arranged perpendicular to the first set of rails; wherein the storage system comprises a floor element configured to be arranged in a secured position at an upper end of a storage column, wherein the floor element comprises a top surface, on which an operator may stand, a plurality of rail supports and a plurality of moveable rail fasteners, the rail supports are arranged at a periphery of the floor element and the rail supports are configured to engage with the rails to support the floor element at a fixed level relative to the rail grid when the floor element is in the secured position; and the rail fasteners are moveable between a release position and a locking position, in the release position, the rail fasteners can move past the rails to allow the floor element to move down into the secured position where the floor element is supported by the rail supports, and in the locking position the rail fasteners are arranged to restrict movement of the floor element in the vertical upwards direction, by engaging with the rails, such that the floor element is held in the secured position.

Description

STORAGE SYSTEM, FLOOR ELEMENT, AND METHOD

FIELD

[0001] The present disclosure relates to a floor element for a storage system for storage containers, to a floor element for a storage system, and to a corresponding method.

BACKGROUND

[0002] Fig. 1 discloses a prior art automated storage and retrieval system 1 (i.e. a storage system), with a framework structure too and Figs. 2, 3 and 4 disclose three different prior art container handling vehicles 201,301,401 suitable for operating on such a system 1.

[0003] The framework structure 100 comprises upright members 102 (i.e. vertical column profiles) and a storage volume comprising storage columns 105 arranged in rows between the upright members 102. In these storage columns 105 storage containers 106, also known as bins, are stacked one on top of one another to form stacks 107. The members 102 may typically be made of metal, e.g. extruded aluminium profiles.

[0004] The framework structure 100 of the automated storage and retrieval system 1 comprises a rail system 108 (i.e. a rail grid) arranged across the top of framework structure 100, on which rail system 108 a plurality of container handling vehicles 201,301,401 may be operated to raise storage containers 106 from, and lower storage containers 106 into, the storage columns 105, and also to transport the storage containers 106 above the storage columns 105. The rail system 108 comprises a first set of parallel rails 110 arranged to guide movement of the container handling vehicles 201,301,401 in a first direction X across the top of the frame structure 100, and a second set of parallel rails 111 arranged perpendicular to the first set of rails 110 to guide movement of the container handling vehicles 201,301,401 in a second direction Y which is perpendicular to the first direction X. Containers 106 stored in the columns 105 are accessed by the container handling vehicles 201,301,401 through access openings 112 in the rail system 108 (the access openings 112 may also be termed grid spaces, i.e. the rectangular spaces/openings defined by the rail system 108). The container handling vehicles 201,301,401 can move laterally above the storage columns 105, i.e. in a plane which is parallel to the horizontal X-Y plane.

[0005] The upright members 102 of the framework structure too maybe used to guide the storage containers during raising of the containers out from and lowering of the containers into the columns 105. The stacks 107 of containers 106 are typically self-supportive.

[0006] Each prior art container handling vehicle 201,301,401 comprises a vehicle body 201a, 301a, 401a and a wheel assembly featuring first and second sets of wheels 201b, 201c, 301b, 301c, 401b, 401c which enable the lateral movement of the container handling vehicles 201,301,401 in the X direction and in the Y direction, respectively. In Figs. 2, 3 and 4 two wheels in each set are fully visible. The first set of wheels 201b, 301b, 401b is arranged to engage with two adjacent rails of the first set 110 of rails, and the second set of wheels 201c, 301c, 401c is arranged to engage with two adjacent rails of the second set 111 of rails. At least one of the sets of wheels 201b, 301b, 201c, 301c, 401b, 401c can be lifted and lowered, so that the first set of wheels 201b, 301b, 401b and/or the second set of wheels 201c, 301c, 401c can be engaged with the respective set of rails 110, 111 at any one time.

[0007] Each prior art container handling vehicle 201,301,401 also comprises a lift device 404, see fig. 4, for vertical transportation of storage containers 106 (i.e. a container lift device), e.g. raising a storage container 106 from, and lowering a storage container 106 into, a storage column 105. The lift device 404 features a lifting frame 2 comprising container connectors 3, adapted to engage connecting recesses 13 at an upper rim of the sidewalls 14 of a storage container 106, see fig. 5, and guiding pins 4. The guiding pins 4 are arranged to interact with guiding pin recesses 7 at the corners of the storage container and ensure a correct alignment of the lifting frame 2 and container connectors 3 relative to the storage container. The guiding pins 4 will also assist in guiding the lifting frame 2 relative to the upright members of the storage column 105. The lifting frame 2 can be lowered from the vehicle 201,301,401 so that the position of the lifting frame 2 with respect to the vehicle 201,301,401 can be adjusted in a third direction which is orthogonal the first direction X and the second direction Y. The lifting device of the container handling vehicle 201 is located within the vehicle body 201a in Fig. 2. [0008] To raise or lower the lifting frame 2 (and optionally a connected storage container 106), the lifting frame 2 is suspended from a band drive assembly by lifting bands 5. In the band drive assembly, the lifting bands are commonly spooled on/off at least one rotating lifting shaft or reel arranged in the container handling vehicle. Various designs of band drive assemblies are described in for instance WO 2015/193278 Al, WO 2017/129384 Al and WO 2019/206438 Al.

[0009] Conventionally, and also for the purpose of this application, =i identifies the uppermost layer for storing storage containers below the rail system 108, i.e. the layer immediately below the rail system 108, =2 the second layer below the rail system 108, =3 the third layer etc. In the exemplary prior art disclosed in Fig. 1, Z=8 identifies the lowermost, bottom layer of storage containers. Similarly, X=i...n and Y=i...n identifies the position of each storage column 105 in the horizontal plane. Consequently, as an example, and using the Cartesian coordinate system X, Y, Z indicated in Fig. 1, the storage container identified as 106’ in Fig. 1 can be said to occupy storage position X=i , Y=i, Z=6. The container handling vehicles 201,301,401 can be said to travel in layer Z=o, and each storage column 105 can be identified by its X and Y coordinates. Thus, the storage containers shown in Fig. 1 extending above the rail system 108 are also said to be arranged in layer Z=o.

[0010] The storage volume of the framework structure 100 has often been referred to as a grid 104, where the possible storage positions within this grid are referred to as storage cells. Each storage column may be identified by a position in an X- and V-direction, while each storage cell may be identified by a container number in the X-, Y- and Z-direction.

[0011] Each prior art container handling vehicle 201,301,401 comprises a storage compartment or space for receiving and stowing a storage container 106 when transporting the storage container 106 across the rail system 108. The storage space may comprise a cavity arranged internally within the vehicle body 201a as shown in Figs. 2 and 4 and as described in e.g. WO2O15/193278A1 and W02019/206487A1, the contents of which are incorporated herein by reference.

[0012] Fig. 3 shows an alternative configuration of a container handling vehicle 301 with a cantilever construction. Such a vehicle is described in detail in e.g. NO317366, the contents of which are also incorporated herein by reference. [0013] The cavity container handling vehicles 201 shown in Fig. 2 may have a footprint that covers an area with dimensions in the X and Y directions which is generally equal to the lateral extent of a storage column 105, e.g. as is described in WO2O15/193278A1, the contents of which are incorporated herein by reference. The term 'lateral' used herein may mean 'horizontal'.

[0014] Alternatively, the cavity container handling vehicles 401 may have a footprint which is larger than the lateral area defined by a storage column 105 as shown in Fig. 1 and 4, e.g. as is disclosed in W02014/090684A1 or W02019/206487A1.

[0015] The rail system 108 typically comprises rails with grooves in which the wheels of the vehicles run. Alternatively, the rails may comprise upwardly protruding elements, where the wheels of the vehicles comprise flanges to prevent derailing. These grooves and upwardly protruding elements are collectively known as tracks. Each rail may comprise one track, or each rail may comprise two parallel tracks.

[0016] W02018/146304A1, the contents of which are incorporated herein by reference, illustrates a typical configuration of rail system 108 comprising rails and parallel tracks in both X and Y directions forming a rail grid.

[0017] In the framework structure too, most of the columns 105 are storage columns 105, i.e. columns 105 where storage containers 106 are stored in stacks 107. However, some columns 105 may have other purposes. In Fig. 1, columns 119 and 120 are such special-purpose columns used by the container handling vehicles 201,301,401 to drop off and/or pick up storage containers 106 so that they can be transported to an access station (not shown) where the storage containers 106 can be accessed from outside of the framework structure 100 or transferred out of or into the framework structure 100. Within the art, such a location is normally referred to as a ‘port’ and the column in which the port is located maybe referred to as a ‘port column’ 119,120. The transportation to the access station maybe in any direction, that is horizontal, tilted and/or vertical. For example, the storage containers 106 maybe placed in a random or dedicated column 105 within the framework structure 100, then picked up by any container handling vehicle and transported to a port column 119,120 for further transportation to an access station. Note that the term ‘tilted’ means transportation of storage containers 106 having a general transportation orientation somewhere between horizontal and vertical.

[0018] In Fig. 1, the first port column 119 may for example be a dedicated drop-off port column where the container handling vehicles 201,301,401 can drop off storage containers 106 to be transported to an access or a transfer station, and the second port column 120 maybe a dedicated pick-up port column where the container handling vehicles 201,301,401 can pick up storage containers 106 that have been transported from an access or a transfer station.

[0019] The access station may typically be a picking or a stocking station where product items are removed from or positioned into the storage containers 106. In a picking or a stocking station, the storage containers 106 are normally not removed from the automated storage and retrieval system 1 but are returned into the framework structure 100 again once accessed. A port can also be used for transferring storage containers to another storage facility (e.g. to another framework structure or to another automated storage and retrieval system), to a transport vehicle (e.g. a train or a lorry), or to a production facility.

[0020] A conveyor system comprising conveyors is normally employed to transport the storage containers between the port columns 119,120 and the access station.

[0021] If the port columns 119,120 and the access station are located at different levels, the conveyor system may comprise a lift device with a vertical component for transporting the storage containers 106 vertically between the port column 119,120 and the access station.

[0022] The conveyor system maybe arranged to transfer storage containers 106 between different framework structures, e.g. as is described in W02014/075937A1, the contents of which are incorporated herein by reference. The conveyor system in WO2O14/O75937A1 is a storage container lift arranged to transport a storage container between two vertically separated framework structures 100.

[0023] When a storage container 106 stored in one of the storage columns 105 disclosed in Fig. 1 is to be accessed, one of the container handling vehicles 201,301,401 is instructed to retrieve the target storage container 106 from its position and transport it to the drop-off port column 119. This operation involves moving the container handling vehicle 201,301,401 to a location above the storage column 105 in which the target storage container 106 is positioned, retrieving the storage container 106 from the storage column 105 using the container handling vehicle’s 201,301,401 lifting device 404, and transporting the storage container 106 to the drop-off port column 119. If the target storage container 106 is located deep within a stack 107, i.e. with one or a plurality of other storage containers 106 positioned above the target storage container 106, the operation also involves temporarily moving the above-positioned storage containers prior to lifting the target storage container 106 from the storage column 105. This step, which is sometimes referred to as “digging” within the art, maybe performed with the same container handling vehicle that is subsequently used for transporting the target storage container to the drop-off port column 119, or with one or a plurality of other cooperating container handling vehicles. Alternatively, or in addition, the automated storage and retrieval system 1 may have container handling vehicles 201,301,401 specifically dedicated to the task of temporarily removing storage containers 106 from a storage column 105. Once the target storage container 106 has been removed from the storage column 105, the temporarily removed storage containers 106 can be repositioned into the original storage column 105. However, the removed storage containers 106 may alternatively be relocated to other storage columns 105.

[0024] When a storage container 106 is to be stored in one of the columns 105, one of the container handling vehicles 201,301,401 is instructed to pick up the storage container 106 from the pick-up port column 120 and transport it to a location above the storage column 105 where it is to be stored. After any storage containers 106 positioned at or above the target position within the stack 107 have been removed, the container handling vehicle 201,301,401 positions the storage container 106 at the desired position. The removed storage containers 106 may then be lowered back into the storage column 105 or relocated to other storage columns 105.

[0025] For monitoring and controlling the storage system 1, e.g. monitoring and controlling the location of respective storage containers 106 within the framework structure 100, the content of each storage container 106, and the movement of the container handling vehicles 201,301,401 so that a desired storage container 106 can be delivered to the desired location at the desired time without the container handling vehicles 201,301,401 colliding with each other, the storage 1 comprises a control system 500 which typically is computerized and which typically comprises a database for keeping track of the storage containers 106.

[0026] A problem with automated storage and retrieval systems, as described above, is the difficulty that service personnel face in accessing equipment arranged on the framework structure 100 when the equipment needs service. Such equipment includes container-handling vehicles, charging stations for container-handling vehicles etc. For instance, if a container-handling vehicle stops working while out on the rail grid 108, there is no easy way for service personnel to reach the vehicle. One option is to use a service vehicle unit, which is a manually driven personnel vehicle. However, these vehicles are bothersome to use and do not allow the operator to transport any required equipment out on the rail grid. Further, the area surrounding equipment in need of service is usually made up of open ended storage columns 105, making the service work difficult to perform, at least in a secure manner. Similar difficulties may also arise in connection with reconstruction and maintenance of the framework structure itself.

[0027] Use of floor elements to allow access to areas upon the rail grid is described in WO 2019/081092 Al. Although providing a practical method for an operator to move on top of the rail grid, there is still a security hazard of e.g. falling off the floor elements.

SUMMARY

[0028] The present disclosure provides an automated storage and retrieval system, a floor element, and corresponding method, whereby personnel may operate upon the rail grid of a storage system in a secure manner.

[0029] In a first aspect, the present disclosure provides a storage system for storage containers, the storage system comprising a framework structure having a rail grid configured to allow a container handling vehicle to move thereon, the framework structure defining a plurality of storage columns below the rail grid, in which storage columns storage containers are arranged one on top of another in vertical stacks; the rail grid comprises a first set of parallel rails and a second set of parallel rails arranged perpendicular to the first set of rails; wherein the storage system comprises a floor element configured to be arranged in a secured position at an upper end of a storage column, wherein the floor element comprises a top surface, on which an operator may stand, a plurality of rail supports and a plurality of moveable rail fasteners, the rail supports are arranged at a periphery, i.e. a horizontal periphery, of the floor element and the rail supports are configured to engage with the rails to support the floor element at a fixed level relative to the rail grid when the floor element is in the secured position; and the rail fasteners are moveable between a release position and a locking position, in the release position, the rail fasteners can move past the rails to allow the floor element to move down into the secured position where the floor element is supported by the rail supports, and in the locking position the rail fasteners are arranged to restrict movement of the floor element in the vertical upwards direction, by engaging with the rails, such that the floor element is held in the secured position.

[0030] The storage system may comprise a plurality of floor elements.

[0031] The secured position may also be termed “the operable position”, “the floor providing position", “the support position” or “the working position”. In the secured position, the rail fasteners maybe in any of the release position and the locking position.

[0032] In some embodiments of the storage system, each rail support may comprise a downwards facing support surface configured to engage with an upwards facing surface of the rails to support the floor element at a fixed level relative to the rail grid when the floor element is in the secured position. In other words, the downwards facing support surface maybe configured to rest or be supported on an upwards facing surface of the rails.

[0033] In some embodiments of the storage system, at least a portion of each rail fastener may be arranged under a downwards facing surface of a respective rail to restrict upwards movement of the floor element when the rail fastener is in the locking position. [0034] Iⁿ some embodiments of the storage system, the floor element may comprise at least one anchoring element for safety equipment, optionally wherein the anchoring element comprises at least one of: an eyelet for fastening a carabiner of a safety harness, a recess for connecting a safety anchor or a threaded hole for securing a safety barrier.

[0035] In some embodiments of the storage system, each rail fastener is biased towards the locking position by a resilient element, such as a spring.

[0036] In some embodiments of the storage system, the floor element may comprise at least one rail fastener on each of two opposite sides of the floor element.

[0037] The top surface of the floor element may be flush with, or slightly below or above, an upper level of the rail grid when the floor element is in the support position. The top surface maybe arranged at a level relative to an upper level of the rail grid which allows a container handling vehicle to move over the floor.

[0038] In some embodiments of the storage system, the container handling vehicle may comprise a vertically moveable lifting frame for lifting a storage container from, or lowering a storage container into, any of the storage columns, and wherein the floor element can be releasably connected to the lifting frame.

[0039] In some embodiments of the storage system, the floor element may comprise recesses for releasable connection to the lifting frame. The lifting frame may comprise grippers for connection to the recesses of the floor element. The grippers maybe suitable for connection to any of the floor element and the storage containers. The recesses maybe arranged at the top surface of the floor element.

[0040] In some embodiments of the storage system, each rail fastener maybe moved between the locking position and the release position by engaging with the lifting frame of the container handling vehicle or by a dedicated manual actuator assembly. When the rail fasteners are moved by engagement with the lifting frame, the rail fasteners may be moved by engaging directly or indirectly with the guiding pins or the grippers of the lifting frame. When engaging with the grippers, the rail fasteners are moved from the locking position to the release position when the grippers are connected to the floor element. [0041] The actuator assembly may comprise a manually actuated linkage system configured to move the rail fasteners between the locking position and the release position. The linkage system maybe connected to or comprise a rotatable hub, the rotatable hub operably connected to the linkage system, such that the linkage system will move the rail fasteners between the locking position and the release position during rotation of the hub.

[0042] In some embodiments of the storage system, the lifting frame may comprise guiding pins extending below a lower bottom surface of the lifting frame, and the rail fasteners are configured to interact with the guiding pins when the lifting frame is connected to the floor element, such that the rail fasteners are moved from the locking position to the release position. In other words, the rail fasteners are configured to be moved by the guiding pins from the locking position to the release position when the lifting frame is connected to the floor element. Each of the rail fasteners may comprise a curved or inclined surface engaging with one of the guiding pins when the lifting frame is connected to the floor element, i.e. during connection of the lifting frame to the floor element, such that the rail fasteners are moved from the locking position to the release position.

[0043] In some embodiments of the storage system, the first set of parallel rails and the second set of parallel rails define access openings arranged at the upper end of each of the storage columns. The access openings maybe rectangular. The access openings having a periphery or size allowing passage of a storage container through the rail grid and into a storage column.

[0044] In some embodiments of the storage system, the rails of the rail grid may provide or comprise horizontally extending recesses at the periphery of the access openings.

[0045] Each rail of the rail grid may comprise at least one horizontally extending recess on opposite sides of the rail. Each rail may comprise an upper and a lower horizontally extending recess on opposite sides of the rail.

[0046] In some embodiments of the storage system, each downwards facing support surface of the rail supports may be configured to engage with an upwards facing surface of one of the horizontally extending recesses to support the floor element at the fixed level relative to the rail grid when the floor element is in the secured position. [0047] Iⁿ some embodiments of the storage system, at least a portion of each rail fastener is arranged under a downwards facing surface of the horizontally extending recesses to restrict upwards movement of the floor element when the rail fastener is in the locking position. The recesses maybe arranged at an inner periphery of the access opening in which the floor element is in the secured position. The inner periphery may be defined by portions of the first set of rails and the second set of rails. The portions of the first set of rails and the second set of rails providing the access opening.

[0048] In other words, at least a portion of each rail fastener may be arranged within one of the horizontally extending recesses to restrict upwards movement of the floor element when the rail fastener is in the lock position.

[0049] At least a portion of each rail fastener may be arranged under a downwards facing surface of the horizontally extending recesses to restrict upwards movement of the floor element when the rail fastener is in the lock position and the floor element is in the secured position. Fastening the floor element via the horizontally extending recesses is advantageous in that the height of the floor elements maybe minimized.

[0050] In some embodiments of the storage system, at least a portion of each rail fastener maybe arranged under one of the rails defining the access opening at the upper end of the storage column at which the floor element is arranged to restrict upwards movement of the floor element when the rail fastener is in the locking position.

[0051] In some embodiments of the storage system, each of the rail supports may comprise a support portion and an actuator portion, and each rail support is pivotably connected to the floor element such that the support portion is moved from a first position to a second position in a horizontal direction outwardly beyond an inner periphery of the access opening when the actuator portion is deflected inwardly of the inner periphery of the access opening by interaction with an upper portion of the rails during lowering of the floor element into the access opening to the secured position. The upper portion of the rails maybe an upper edge of the rails. The upper edge arranged at an upper end of the access opening.

[0052] In some embodiments of the storage system, the support portion may be biased towards the first position by a resilient element, e.g. a spring. [0053] Iⁿ some embodiments of the storage system, the support portion may comprise the downwards facing support surface of the rail supports.

[0054] In some embodiments of the storage system, the support portion and the actuator portion are arranged at opposite ends of a lever, the lever being pivotably connected to the floor element by a pivot connection arranged between the support portion and the actuator portion.

[0055] In some embodiments of the storage system, the anchoring element maybe a recess for connecting a safety anchor, the safety anchor comprises locking pins being moveable between a retracted position and an extended position, in the retracted position the safety anchor can be inserted into the recess and in the extended position the securing pins will prevent the safety anchor from exiting the recess. In the extended position the locking pins will extend beyond a periphery of the recess.

[0056] In some embodiments of the storage system, the safety anchor may comprise a pin holding element to which the locking pins are connected and a housing. The pin holding element is arranged within the housing and is moveable relative to the housing between the extended position and the retracted. In the extended position, the locking pins extend beyond an outer wall of the housing. In the retracted position, the locking pins are retracted relative to the extended position. In other words, the locking pins are closer to a vertical centreline of the safety anchor when in the retracted position than in the extended position. The pin holding element maybe biased towards the first position by springs.

[0057] The framework structures may comprise a plurality of vertical column profiles defining the storage columns. The vertical column profiles may comprise vertical corner sections for guiding corresponding corners of a lifting frame lowered or raised within the storage columns.

[0058] The rail grid maybe arranged on top of, and supported by, the vertical column profiles of the framework structure.

[0059] The first and second set of parallel rails of the rail grid maybe dual track rails.

[0060] The container handling vehicle may comprise a wheel assembly which enables movement of the container handling vehicle in the two perpendicular directions on the corresponding rail grid. The wheel assembly may feature a first and a second set of wheels. The first set of wheels maybe arranged to engage with a first set of parallel rails of the rail grid, and the second set of wheels maybe arranged to engage with a second set of parallel rails of the rail grid. At least one of the sets of wheels can be lifted and lowered relative to the other set of wheels, so that the first set of wheels and/or the second set of wheels can be engaged with the respective set of rails at any one time.

[0061] In a second aspect, the present disclosure provides a floor element for a storage system according to any embodiment of the first aspect. The floor element comprising a top surface on which an operator can stand; a plurality of rail supports, the rail supports comprise downwards facing support surfaces extending, or being extendable, beyond a horizontal periphery of the top surface such that the floor element can be supported by the downwards facing support surfaces by engaging two parallel rails arranged on opposite sides of the top surface and/or arranged on opposite sides of the floor element; and a plurality of rail fasteners, the rail fastener being movable to a locking position for engagement with two parallel rails arranged on opposite sides of the top surface, and/or arranged on opposite sides of the floor element, such that vertical movement of the floor element relative to the parallel rails can be restricted.

[0062] In a third aspect, the present disclosure provides a floor element for connection to a rail grid, or for connection between two parallel rails, the floor element comprising a top surface on which an operator can stand; a plurality of rail supports, the rail supports comprise downwards facing support surfaces extending, or being extendable, beyond a horizontal periphery of the top surface such that the floor element can be supported by the downwards facing support surfaces by engaging two parallel rails arranged on opposite sides of the top surface and/or arranged on opposite sides of the floor element; and a plurality of rail fasteners, the rail fastener being movable to a locking position for engagement with two parallel rails arranged on opposite sides of the top surface, and/or arranged on opposite sides of the floor element, such that vertical movement of the floor element relative to the parallel rails can be restricted.

[0063] In a fourth aspect, the present disclosure provides a floor element for providing a platform in a rail grid of a storage system, the floor element comprising: an upper surface configured to provide a surface on which an operator can stand; a plurality of rail supports configured to be supported by the rail grid; and a plurality of rail fasteners each movable between a locking position for engagement with the rail grid, and a release position for allowing movement of the rail fastener relative to the rail grid.

[0064] The floor element of the second, third and fourth aspect may comprise any of the features of the floor element used in the storage system according to the first aspect.

[0065] In a fifth aspect, the present disclosure provides a method of fastening a floor element at the upper end of a storage column in a storage system according to any embodiment of the first aspect. The method comprising the steps of: lowering the floor element in a vertical direction towards the upper end of one of the storage columns until the rail supports engage with the rails and support the floor element at a fixed level relative to the rail grid; and moving the rail fasteners from the release position to the locking position such that movement of the floor element in the vertical upwards direction, i.e. a vertical direction relative to the rail grid, is restricted.

[0066] In some embodiments, the method may comprise the step of: connecting a safety equipment, such as a harness or a barrier, to the floor element.

[0067] In a sixth aspect, the present disclosure provides a safety anchor for a floor element according to the second, third and fourth aspect, the floor element comprising a recess in the upper surface. The safety anchor comprises locking pins being moveable between a retracted position and an extended position, in the retracted position the safety anchor can be inserted into the recess and in the extended position the securing pins will prevent the safety anchor from exiting the recess. In the extended position the locking pins will extend beyond a periphery of the recess.

[oo68] In some embodiments, the safety anchor may comprise a pin holding element to which the locking pins are connected and a housing. The pin holding element is arranged within the housing and is moveable relative to the housing between the extended position and the retracted position. In the extended position, the locking pins extend beyond an outer wall of the housing. In the retracted position, the locking pins are retracted relative to the extended position. In other words, the locking pins are closer to a vertical centreline of the safety anchor when in the retracted position than in the extended position. The pin holding element maybe biased towards the first position by springs. The outer wall of the housing may have a periphery fitting within the recess.

BRIEF DESCRIPTION OF THE DRAWINGS

[0069] The present disclosure is described in detail by reference to the following drawings:

[0070] Fig. 1 is a perspective view of a framework structure of a prior art automated storage and retrieval system.

[0071] Fig. 2 is a perspective view of a prior art container handling vehicle having a centrally arranged cavity for carrying storage containers therein.

[0072] Fig. 3 is a perspective view of a prior art container handling vehicle having a cantilevered section for carrying storage containers underneath.

[0073] Fig. 4 is a perspective view of a prior art container handling vehicle, wherein a container lifting assembly is shown.

[0074] Fig. 5 is a perspective view of a storage container suitable for the storage system in fig. 1.

[0075] Figs. 6-14 show a first exemplary floor element for use in a storage system according to the present disclosure.

[0076] Figs. 15-17 show a second exemplary floor element for use in a storage system according to the present disclosure. [0077] Figs. i8a-f shows a safety anchor for use with the second exemplary floor element in figs. 15-17.

[0078] Figs. 19-26 show a third exemplary floor element for use in a storage system according to the present disclosure.

DETAILED DESCRIPTION

[0079] In overview, the present disclosure provides a storage system for storage containers, in which a floor element having a top surface on which an operator can stand, is moveable between different locations on the storage system and is lockable in place. Accordingly, the floor element can be utilised to allow personnel, for example maintenance personnel, to safely stand on the storage system. A floor element for use in such a storage system, and a method of fastening such a floor element in place, are also provided.

[0080] In the following, examples of the present disclosure will be discussed in more detail with reference to the appended drawings. The drawings are not intended to limit the disclosure to the illustrated subject-matter.

[0081] As discussed above, the prior art storage systems as shown in fig, 1 may present challenges for secure movement and operation of an operator upon the rail grid.

[0082] A prior art solution overcoming at least some of the safety concerns regarding movement of an operator upon the rail grid is disclosed in patent application WO 2019/081092 Al. A potential safety hazard not addressed by the prior art solution is that an operator may have a mishap and e.g. step or fall off the floor elements and into an adjacent storage column or off a side of the framework structure 100.

[0083] The inventive floor element and storage system disclosed below are configured to provide improved safety for an operator performing tasks on top of a storage system. The configuration of the framework structure 100, container handling vehicles and storage containers 106 of the inventive storage system maybe as disclosed for the prior art storage system 1 discussed in the background section above.

[0084] Thus, each exemplary storage systems, see fig. 12 and 17, comprises a framework structure 100 having vertical column profiles 102 defining a plurality of storage columns 105 and a rail grid 108 arranged above the storage columns 105. The rail grid 108 is configured to allow a container handling vehicle (not shown but maybe similar to the container handling vehicles shown in figs. 2-4) to move thereon. The rail grid 108 comprises a first set of parallel rails 110 and a second set of parallel rails 111 arranged perpendicular to the first set of rails 110. The rails 110,111 define access openings 112 at upper ends of the storage columns 105. The storage columns 105 may accommodate storage containers 106 being supported on top of each other in vertical stacks.

[0085] To provide increased safety for an operator performing tasks on top of the framework structure 100, the exemplary storage systems comprise a floor element 8, 8’, 8” configured to be arranged in a secured position at an upper end of a storage column 105, see figs. 12 and 17.

[0086] A first exemplary floor element 8 is shown in figs. 6-14. The floor element 8 comprises a top surface 27, on which an operator may stand, a plurality of rail supports 10 and a plurality of moveable rail fasteners 12. To allow the floor element 8 to be moved on top of the rail grid 108 by a prior art container handling vehicle, the floor element 8 comprises recesses 9 for releasable connection to a lifting frame 2 via grippers 3.

[0087] The rail supports 10 are arranged at, and extending beyond, a periphery of the floor element 8. One of the rail supports 10 are positioned on each side of the floor element. Each rail support 10 features a downwards facing support surface 29 being configured to engage with an upper surface 31 (i.e. an upwards facing surface) of the rails 110,111 to support the floor element 8 at a fixed and predetermined level relative to the rail grid 108 when the floor element 8 is in the secured position, see fig 13.

[0088] The rail fasteners 12 are moveable between a release position and a locking position. In the release position, see fig. 11, the rail fasteners can move past the rails 110,111 to allow the floor element 8 to move down into the secured position where the floor element 8 is supported by the rail supports 10. In the locking position, see fig. 14, each rail fastener 12 is arranged to restrict movement of the floor element 8 in the vertical upwards direction, by engaging with the rails 110,111. When the rail fasteners 12 are in the locking position, the floor element is held in the secured position. [0089] To hold the floor element in the secured position, a portion of each rail fastener 12 is arranged under a downwards facing surface 18 of a respective rail 110 to restrict upwards movement of the floor element 8, see fig. 14. The rails 110,111 have horizontally extending recesses 22,23 at the periphery of the access openings 112, and the downwards facing surface 18 is a surface of one of the recesses 22. Each rail fastener 12 is biased towards the locking position by a spring 25, i.e. a resilient element.

[0090] The lifting frame 2 intended to releasably connect and move the floor element 8 comprises guiding pins 4 extending below a lower bottom surface 15 of the lifting frame, see figs. 8-11. The rail fasteners 12 are configured to interact with the guiding pins 4 when the lifting frame is connected to the floor element 8. During lowering of the lifting frame 2 into contact with the floor element 8, the guiding pins will push the rail fasteners 12 from the locking position to the release position. In this manner, the guiding pins hold the rail fasteners 12 in the release position when the lifting frame 2 retrieves the floor element from the secured position and when lowering the floor element into the secured position. When the floor element has been arranged at a desired secured position, the lifting frame 2 is disconnected and removed from the floor element 8. The removal of the guiding pins 4 allow the rail fasteners 12 to move from the release position to the locking position, and the floor element is held in place.

[0091] In alternative embodiments, it is envisioned that the rail fasteners 12 maybe moved between the locking position to the release position by operating the grippers 3 of the lifting frame 2. For example, the rail fasteners 12 maybe operatively connected to the grippers 3 such that the rail fasteners 12 are moved from the locking position to the release position when the grippers 3 are moved to releasably connect the lifting frame 2 to the floor element 8.

[0092] The floor element 8 comprises anchoring elements for safety equipment in the form of threaded holes 19 for securing a safety barrier (not shown). Depending on the configuration of a connecting interface between the safety barrier and the floor element, the recesses 9 for connection to the lifting frame 2 may also be used as anchoring elements for the safety barrier. Other safety equipment such as a carabiner of a safety harness (not shown) and/or a safety anchor may also be connected to the floor element 2 via a suitable anchoring element. [0093] A second exemplary floor element 8’ is shown in figs. 15-17. The floor element comprises rail supports 10 and rail fasteners 12 as discussed for the first exemplary embodiment.

[0094] The floor element 8’ comprises an anchoring element in the form of a circular recess 20 configured to receive a safety anchor 26 to which a desired safety equipment maybe connected via eyelets/through-holes 44.

[0095] Details of the safety anchor is shown in figs. i8a-i8f. The safety anchor is releasably attached to the floor element via a plurality of locking pins 37. The safety anchor comprises a pin holding element 38 to which the locking pins 37 are connected and a housing 39. The pin holding element 38 is arranged within the housing 39 and is moveable relative to the housing 39 between a first position and a second position. In the first position, see fig. i8d, the locking pins 37 extend beyond an outer wall of the housing 39. In the second position, see fig. i8e, the locking pins 37 are retracted relative to the first position. The pin holding element 38 is biased towards the first position by springs 40.

[0096] A tool 41, see fig. i8f, is used to fasten the safety anchor to the floor element 8’. To attach the safety anchor to the floor element 8’, the tool is first attached to the safety anchor 26. The tool 41 is attached by first pushing the tool towards the safety anchor 26 to push the pin holding element 37 into the second position, see fig. i8e, and secondly by turning the tool 41 such that a set of latches 42 are moved to engage respective latch grooves 43. When the tool 41 is attached and latched, the pin holding element 38 is moved and kept in the second position. The safety anchor may then be inserted into the recess 20 without interference from the locking pins 37. After insertion of the safety anchor 26, the tool 41 is disconnected from the safety anchor 26 and the pin holding element 38 is moved into the first position by the springs 40, see fig. i8d. When the safety anchor 26 is inserted into the recess 20 and the pin holding element 38 is in the first position, the safety anchor 26 is secured to the floor element 8’ by the locking pins 37.

[0097] A third exemplary floor element 8” is shown in figs. 19-26. The third exemplary floor element has the same function as the floor elements discussed above, but comprises rail supports 11 and rail fasteners 28 of a different configuration. [0098] Each of the rail supports 11 comprises a support portion 32 and an actuator portion 33, see figs. 23-25, and is pivotably connected to the floor element 8”. The support portion 32 and the actuator portion 33 are arranged at opposite ends of a lever 35 which is pivotably connected to the floor element 8” by a pivot connection 36 arranged between the support portion 32 and the actuator portion

33. The support portion 32 comprises a downwards facing support surface 30.

[0099] The rail support 11 is configured such that the support portion 32 is moved from a first position, fig. 22, to a second position, fig. 23, in a horizontal direction outwardly beyond an inner periphery of an access opening 112 of the rail grid 108 when the actuator portion 33 is deflected inwardly of the inner periphery of the access opening 112 by interaction with an upper portion of the rails 110 during lowering of the floor element 8 into the access opening to the secured position. When in the secured position, the support surface 30 rests on an upwards facing surface of the rails 110,111, see fig. 24. The upwards facing surface 17 is a surface defining parts of a horizontally extending recess 22 of the rail 110 at the periphery of the access openings 112.

[0100] The support portion is biased towards the first position by a spring 34, i.e. a resilient element.

[0101] The rail fasteners 28 are moveable between a release position and a locking position. In the release position, see figs. 21 and 23-25, the rail fasteners can move past the rails 110,111 to allow the floor element 8” to move down into the secured position where the floor element 8” is supported by the rail supports 11. In the locking position, see figs. 22 and 26, each rail fastener 28 is arranged to restrict movement of the floor element 8” in the vertical upwards direction, by engaging with the rails 110,111. When the rail fasteners 28 are in the locking position, the floor element 8” is held in the secured position.

[0102] To hold the floor element 8” in the secured position, a portion of each rail fastener 28 is arranged under a downwards facing surface 24 in the respective rail 110 to restrict upwards movement of the floor element 8”, see fig. 26. The rails 110,111 have horizontally extending recesses 22,23 at the periphery of the access openings 112, and the downwards facing surface 24 is a surface of one of the recesses 23. Each rail fastener 28 is biased towards the locking position by a spring

34, i.e. a resilient element. [0103] The rail fasteners are operably connected to a rotatable hub 45 by a linkage assembly 46. The linkage assembly 46 is configured to move the rail fasteners 28 between the release position and the locking position when the hub 45 is rotated, see figs. 21 and 22. The hub 45 performs the function of an anchoring element featuring an eyelet/through-hole 21 by which a desired safety equipment maybe connected.

Also disclosed herein are examples according to the following numbered clauses.

1. A storage system (1) for storage containers, the storage system comprising a framework structure (100) having a rail grid (108) configured to allow a container handling vehicle (501) to move thereon, the framework structure defining a plurality of storage columns (105) below the rail grid, in which storage columns storage containers (106) are arranged one on top of another in vertical stacks; the rail grid comprises a first set of parallel rails (110) and a second set of parallel rails (111) arranged perpendicular to the first set of rails; wherein the storage system comprises a floor element (8) configured to be arranged in a secured position at an upper end of a storage column, wherein the floor element (8) comprises a top surface (27), on which an operator may stand, a plurality of rail supports (10,11) and a plurality of moveable rail fasteners (12,28), the rail supports (10,11) are arranged at a periphery of the floor element (8) and the rail supports are configured to engage with the rails to support the floor element at a fixed level relative to the rail grid (108) when the floor element is in the secured position; and the rail fasteners (12,28) are moveable between a release position and a locking position, in the release position, the rail fasteners can move past the rails to allow the floor element to move down into the secured position where the floor element is supported by the rail supports, and in the locking position the rail fasteners are arranged to restrict movement of the floor element in the vertical upwards direction, by engaging with the rails, such that the floor element is held in the secured position.

2. A storage system according to clause 1, wherein each rail support comprises a downwards facing support surface (29,30) configured to engage with an upwards facing surface (31,17) of the rails to support the floor element at a fixed level relative to the rail grid (108) when the floor element is in the secured position.

3. A storage system according to clause 1 or 2, wherein at least a portion of each rail fastener (12,28) is arranged under a downwards facing surface (18,24) of a respective rail to restrict upwards movement of the floor element when the rail fastener is in the locking position.

4. A storage system according to any of the preceding clauses, wherein the floor element (8) comprises at least one anchoring element (19,20,21) for safety equipment, optionally wherein the anchoring element comprises at least one of: an eyelet (21) for fastening a carabiner of a safety harness, a recess (20) for connecting a safety anchor (26) or a threaded hole (19) for securing a safety barrier.

5. A storage system according to any of the preceding clauses, wherein each rail fastener is biased towards the locking position by a resilient element (25).

6. A storage system according to any of the preceding clauses, wherein the floor element (8) comprises at least one rail fastener on each of two opposite sides of the floor element.

7. A storage system according to any of the preceding clauses, wherein the container handling vehicle (501) comprises a vertically moveable lifting frame (2) for lifting a storage container (106) from, or lowering a storage container into, any of the storage columns (105), and wherein the floor element (8) can be releasably connected to the lifting frame (2).

8. A storage system according to clause 7, wherein the floor element comprises recesses (9) for releasable connection to the lifting frame (2).

9. A storage system according to clause 7 or 8, wherein the lifting frame comprises guiding pins (4) extending below a lower bottom surface (15) of the lifting frame, and the rail fasteners (12) are configured to interact with the guiding pins when the lifting frame is connected to the floor element, such that the rail fasteners are moved from the locking position to the release position.

10. A storage system according to any of the preceding clauses, wherein the first set of parallel rails (110) and the second set of parallel rails (111) defines access openings (112) arranged at the upper end of each of the storage columns (105). 11. A storage system according to clause 10, wherein the rails (110,111) provide horizontally extending recesses (22,23) at the periphery of the access openings (112).

12. A storage system according to clause 2 and 11, wherein each downwards facing support surface (30) is configured to engage with an upwards facing surface (17) of one of the horizontally extending recesses (22) to support the floor element (8) at the fixed level relative to the rail grid (108) when the floor element is in the secured position.

13. A storage system according to clause 11 or 12, wherein at least a portion of each rail fastener (12,28) is arranged under a downwards facing surface (18,24) of the horizontally extending recesses (22,23) to restrict upwards movement of the floor element when the rail fastener is in the locking position.

14. A storage system according to any of clauses 10-13, wherein each of the rail supports (11) comprises a support portion (32) and an actuator portion (33), and each rail support is pivotably connected to the floor element (8) such that the support portion (32) is moved from a first position to a second position in a horizontal direction outwardly beyond an inner periphery of the access opening (112) when the actuator portion (33) is deflected inwardly of the inner periphery of the access opening (112) by interaction with an upper portion of the rails during lowering of the floor element (8) into the access opening to the secured position.

15. A storage system according to clause 14, wherein the support portion is biased towards the first position by a resilient element (34).

16. A storage system according to clause 14 or 15, when each is dependent from claim 12, wherein the support portion (32) comprises the downwards facing support surface (30).

17. A storage system according to any of clauses 14 to 16, wherein the support portion (32) and the actuator portion (33) are arranged at opposite ends of a lever (35)? the lever being pivotably connected to the floor element (8) by a pivot connection (36) arranged between the support portion (32) and the actuator portion (33).

18. A storage system according to clause 4, wherein the anchoring element is a recess (20) for connecting a safety anchor (26), the safety anchor comprises locking pins (37) being moveable between a retracted position and an extended position, in the retracted position the safety anchor can be inserted into the recess (20) and in the extended position the securing pins will prevent the safety anchor from exiting the recess.

19. A floor element for a storage system according to any of the preceding clauses, the floor element comprising a top surface (27) on which an operator can stand; a plurality of rail supports (10,11), each rail support comprises a downwards facing support surface (29,30) extending, or being extendable, beyond a horizontal periphery of the top surface such that the floor element can be supported by two parallel rails (110,111) arranged on opposite sides of the top surface; and a plurality of rail fasteners (12,28), each rail fastener being movable to a locking position for engagement with two parallel rails (110,111) arranged on opposite sides of the top surface, such that vertical movement of the floor element relative to the parallel rails (110,111) can be restricted.

20. A method of fastening a floor element at the upper end of a storage column in a storage system according to any of clauses 1-17, comprising the steps of: lowering the floor element (7) in a vertical direction towards the upper end of one of the storage columns until the rail supports (10,11) engage with the rails and support the floor element at a fixed level relative to the rail grid (108); and moving the rail fasteners (12,28) from the release position to the locking position such that movement of the floor element in the vertical upwards direction is restricted.

21. A method according to clause 20, further comprising the step of: connecting a safety equipment, such as a harness or a barrier, to the floor element.

LIST OF REFERENCE NUMBERS

1 Prior art automated storage and retrieval system

2 Lifting frame

3 Container connector, grippers

4 Guiding pin

5 Lifting bands

6 Vehicle body

7 Guiding pin recess

8, 8’, 8” Floor element

9 Connecting recess io Rail support n Rail support

12 Rail fastener

13 Connecting recess

14 Sidewall of storage container

15 Lower bottom surface of lifting frame

16 Upper rim of storage container

17 Upwards facing surface

18 Downwards facing surface

19 Threaded hole

20 Recess

21 Eyelet, through-hole

22 Horizontally extending recess

23 Horizontally extending recess

24 Downwards facing surface

25 Spring, resilient element Safety anchor

Top surface

Rail fastener

Downwards facing support surface

Upwards facing surface

Support portion

Actuator portion

Spring, resilient element

Lever

Pivot connection

Locking pin

Pin holding element

Housing

Spring, resilient element

Tool

Latch

Latch groove

Eyelet, through-hole

Hub

Linkage assembly ,100’ First framework structure, second framework structure

Upright members of framework structure

Horizontal members of framework structure

Storage grid

Storage column 6 Storage container 6’ Particular position of storage container 7 Stack 8 Rail system 0 Parallel rails in first direction ( ) 0a First rail in first direction (X) 0b Second rail in first direction (X) 1 Parallel rail in second direction (Y) 1a First rail of second direction (Y) 1b Second rail of second direction (Y) 2 Access opening, storage column 3 Access opening, buffer column 9 First port column 0 Second port column 01 Prior art container handling vehicle 01a Vehicle body of the container handling vehicle 20101b Drive means / wheel arrangement, first direction ( )01c Drive means / wheel arrangement, second direction (Y)01 Prior art cantilever container handling vehicle Oia Vehicle body of the container handling vehicle 301Oib Drive means in first direction (X) Oic Drive means in second direction (Y) 01 Prior art container handling vehicle 01a Vehicle body of the container handling vehicle 40101b Drive means in first direction (X) 01c Drive means in second direction ( Y) Y Second direction

Z Third direction

Claims

1. A storage system (1) for storage containers, the storage system comprising a framework structure (too) having a rail grid (108) configured to allow a container handling vehicle (501) to move thereon, the framework structure defining a plurality of storage columns (105) below the rail grid; the rail grid comprises a first set of parallel rails (110) and a second set of parallel rails (111) arranged perpendicular to the first set of rails; wherein the storage system comprises a floor element (8) configured to be arranged in a secured position at an upper end of a storage column, wherein the floor element (8) comprises a top surface (27), on which an operator may stand, a plurality of rail supports (10,11) and a plurality of moveable rail fasteners (12,28), the rail supports (10,11) are arranged at a periphery of the floor element (8) and the rail supports are configured to engage with the rails to support the floor element at a fixed level relative to the rail grid (108) when the floor element is in the secured position; and the rail fasteners (12,28) are moveable between a release position and a locking position, in the release position, the rail fasteners can move past the rails to allow the floor element to move down into the secured position where the floor element is supported by the rail supports, and in the locking position the rail fasteners are arranged to restrict movement of the floor element in the vertical upwards direction, by engaging with the rails, such that the floor element is held in the secured position.

2. A storage system according to claim 1, wherein each rail support comprises a downwards facing support surface (29,30) configured to engage with an upwards facing surface (31,17) of the rails to support the floor element at a fixed level relative to the rail grid (108) when the floor element is in the secured position.

3. A storage system according to claim 1 or 2, wherein at least a portion of each rail fastener (12,28) is arranged under a downwards facing surface (18,24) of a respective rail to restrict upwards movement of the floor element when the rail fastener is in the locking position.

4. A storage system according to any of the preceding claims, wherein the floor element (8) comprises at least one anchoring element (19,20,21) for safety equipment, optionally wherein the anchoring element comprises at least one of: an eyelet (21) for fastening a carabiner of a safety harness, a recess (20) for connecting a safety anchor (26) or a threaded hole (19) for securing a safety barrier.

5. A storage system according to claim 4, wherein the anchoring element is a recess (20) for connecting a safety anchor (26), the safety anchor comprises locking pins (37) being moveable between a retracted position and an extended position, in the retracted position the safety anchor can be inserted into the recess (20) and in the extended position the securing pins will prevent the safety anchor from exiting the recess.

6. A storage system according to any of the preceding claims, wherein each rail fastener is biased towards the locking position by a resilient element (25).

7. A storage system according to any of the preceding claims, wherein the floor element (8) comprises at least one rail fastener on each of two opposite sides of the floor element.

8. A storage system according to any of the preceding claims, wherein the floor element (8) is configured to be releasably connected to a lifting frame (2) of a container handling vehicle (501).

9. The storage system of claim 8, further comprising a container handling vehicle, wherein the container handling vehicle (501) comprises a vertically moveable lifting frame (2) for lifting a storage container (106) from, or lowering a storage container into, any of the storage columns (105), and wherein the floor element (8) can be releasably connected to the lifting frame (2) of the container handling vehicle.

10. A storage system according to claim 8 or claim 9, wherein the floor element comprises recesses (9) for releasable connection to the lifting frame (2).

11. A storage system according to any of claims 8 to 10, wherein the lifting frame comprises guiding pins (4) extending below a lower bottom surface (15) of the lifting frame, and the rail fasteners (12) are configured to interact with the guiding pins when the lifting frame is connected to the floor element, such that the rail fasteners are moved from the locking position to the release position.

12. A storage system according to any of the preceding claims, wherein the first set of parallel rails (110) and the second set of parallel rails (111) define access openings (112) arranged at the upper end of each of the storage columns (105).

13. A storage system according to claim 12, wherein the rails (110,111) provide horizontally extending recesses (22,23) at the periphery of the access openings (112).

14. A storage system according to claim 12 or claim 13 when dependent on claim 2, wherein each downwards facing support surface (30) is configured to engage with an upwards facing surface (17) of one of the horizontally extending recesses (22) to support the floor element (8) at the fixed level relative to the rail grid (108) when the floor element is in the secured position.

15. A storage system according to claim 13 or 14, wherein at least a portion of each rail fastener (12,28) is arranged under a downwards facing surface (18,24) of the horizontally extending recesses (22,23) to restrict upwards movement of the floor element when the rail fastener is in the locking position.

16. A storage system according to any of claims 12-15, wherein each of the rail supports (11) comprises a support portion (32) and an actuator portion (33), and each rail support is pivotably connected to the floor element (8) such that the support portion (32) is moved from a first position to a second position in a horizontal direction outwardly beyond an inner periphery of the access opening (112) when the actuator portion (33) is deflected inwardly of the inner periphery of the access opening (112) by interaction with an upper portion of the rails during lowering of the floor element (8) into the access opening to the secured position.

17. A storage system according to claim 16, wherein the support portion is biased towards the first position by a resilient element (34).

18. A storage system according to claim 16 or 17, when dependent from claimi4, wherein the support portion (32) comprises the downwards facing support surface (30).

19. A storage system according to any of claims 16 to 18, wherein the support portion (32) and the actuator portion (33) are arranged at opposite ends of a lever (35 the lever being pivotably connected to the floor element (8) by a pivot connection (36) arranged between the support portion (32) and the actuator portion (33).

20. A floor element for a storage system according to any of the preceding claims, the floor element comprising a top surface (27) on which an operator can stand; a plurality of rail supports (10,11), each rail support comprises a downwards facing support surface (29,30) extending, or being extendable, beyond a horizontal periphery of the top surface such that the floor element can be supported by two parallel rails (110,111) arranged on opposite sides of the top surface; and a plurality of rail fasteners (12,28), each rail fastener being movable to a locking position for engagement with two parallel rails (110,111) arranged on opposite sides of the top surface, such that vertical movement of the floor element relative to the parallel rails (110,111) can be restricted.

21. A method of fastening a floor element at the upper end of a storage column in a storage system according to any of claims 1-19, comprising the steps of: lowering the floor element (7) in a vertical direction towards the upper end of one of the storage columns until the rail supports (10,11) engage with the rails and support the floor element at a fixed level relative to the rail grid (108); and moving the rail fasteners (12,28) from the release position to the locking position such that movement of the floor element in the vertical upwards direction is restricted.

22. A method according to claim 21, further comprising the step of: connecting a safety equipment, such as a harness or a barrier, to the floor element.