Patent Description:
<FIG> discloses a prior art automated storage and retrieval system <NUM> with a framework structure <NUM> and <FIG>, <FIG> disclose three different prior art container handling vehicles <NUM>, <NUM>, <NUM> suitable for operating on such a system <NUM>.

The framework structure <NUM> comprises upright members <NUM> and a storage volume comprising storage columns <NUM> arranged in rows between the upright members <NUM>. In these storage columns <NUM> storage containers <NUM>, also known as bins, are stacked one on top of one another to form container stacks <NUM>. The members <NUM> may typically be made of metal, e.g. extruded aluminum profiles.

The framework structure <NUM> of the automated storage and retrieval system <NUM> comprises a rail system <NUM> arranged across the top of framework structure <NUM>, on which rail system <NUM> a plurality of container handling vehicles <NUM>, <NUM> may be operated to raise storage containers <NUM> from, and lower storage containers <NUM> into, the storage columns <NUM>, and also to transport the storage containers <NUM> above the storage columns <NUM>. The rail system <NUM> comprises a first set of parallel rails <NUM> arranged to guide movement of the container handling vehicles <NUM>, <NUM> in a first direction X across the top of the frame structure <NUM>, and a second set of parallel rails <NUM> arranged perpendicular to the first set of rails <NUM> to guide movement of the container handling vehicles <NUM>, <NUM> in a second direction Y which is perpendicular to the first direction X. Containers <NUM> stored in the columns <NUM> are accessed by the container handling vehicles <NUM>, <NUM> through access openings <NUM> in the rail system <NUM>. The container handling vehicles <NUM>, <NUM> can move laterally above the storage columns <NUM>, i.e. in a plane which is parallel to the horizontal X-Y plane.

The stacks <NUM> of containers <NUM> are typically selfsupportive.

Each prior art container handling vehicle <NUM>, <NUM>, <NUM> comprises a vehicle body 201a, 301a, 401a and first and second sets of wheels 201b, 201c, 301b, 301c, 401b, 401c which enable lateral movement of the container handling vehicles <NUM>, <NUM>, <NUM> in the X direction and in the Y direction, respectively. In <FIG>, 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 <NUM> of rails, and the second set of wheels 201c, 301c, 401c is arranged to engage with two adjacent rails of the second set <NUM> of rails. At least one of the sets of wheels 201b, 201c, 301b, 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 <NUM>, <NUM> at any one time.

Each prior art container handling vehicle <NUM>, <NUM>, <NUM> also comprises a lifting device <NUM>, <NUM> (visible in <FIG>) having a lifting frame part 304a, 404a for vertical transportation of storage containers <NUM>, e.g. raising a storage container <NUM> from, and lowering a storage container <NUM> into, a storage column <NUM>. The lifting device <NUM>, <NUM> comprises one or more gripping/engaging devices which are adapted to engage a storage container <NUM>, and which gripping/engaging devices can be lowered from the vehicle <NUM>, <NUM>, <NUM> so that the position of the gripping/engaging devices with respect to the vehicle <NUM>, <NUM>, <NUM> can be adjusted in a third direction Z (visible for instance in <FIG>) which is orthogonal the first direction X and the second direction Y. Parts of the gripping device of the container handling vehicles <NUM>, <NUM> are shown in <FIG> and <FIG> indicated with reference number. The gripping device of the container handling device <NUM> is located within the vehicle body 201a in <FIG>.

Conventionally, and also for the purpose of this application, Z=<NUM> identifies the uppermost layer available for storage containers below the rails <NUM>, <NUM>, i.e. the layer immediately below the rail system <NUM>, Z=<NUM> the second layer below the rail system <NUM>, Z=<NUM> the third layer etc. In the exemplary prior art disclosed in <FIG>, Z=<NUM> identifies the lowermost, bottom layer of storage containers. Similarly, X=<NUM>. n and Y=<NUM>. Consequently, as an example, and using the Cartesian coordinate system X, Y, Z indicated in <FIG>, the storage container identified as <NUM>' in <FIG> can be said to occupy storage position X=<NUM>, Y = <NUM>, Z=<NUM>. The container handling vehicles <NUM>, <NUM>, <NUM> can be said to travel in layer Z=<NUM>, and each storage column <NUM> can be identified by its X and Y coordinates. Thus, the storage containers shown in <FIG> extending above the rail system <NUM> are also said to be arranged in layer Z=<NUM>.

The storage volume of the framework structure <NUM> has often been referred to as a grid <NUM>, 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 Y-direction, while each storage cell may be identified by a container number in the X-, Y- and Z-direction.

Each prior art container handling vehicle <NUM>, <NUM>, <NUM> comprises a storage compartment or space for receiving and stowing a storage container <NUM> when transporting the storage container <NUM> across the rail system <NUM>. The storage space may comprise a cavity arranged internally within the vehicle body 201a as shown in <FIG> and <FIG> and as described in e.g. <CIT> and <CIT>.

The cavity container handling vehicles <NUM> shown in <FIG> 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 <NUM>, e.g. as is described in <CIT>.

The term 'lateral' used herein may mean 'horizontal'.

Alternatively, the cavity container handling vehicles <NUM> may have a footprint which is larger than the lateral area defined by a storage column <NUM> as shown in <FIG> and as disclosed in <CIT> or <CIT>.

Each rail may comprise one track, or each rail may comprise two parallel tracks; in other rail systems <NUM>, each rail in one direction may comprise one track and each rail in the other perpendicular direction may comprise two tracks. The rail system may also comprise a double track rail in one of the X or Y direction and a single track rail in the other of the X or Y direction. A double track rail may comprise two rail members, each with a track, which are fastened together.

In <FIG>, columns <NUM> and <NUM> are such special-purpose columns used by the container handling vehicles <NUM>, <NUM>, <NUM> to drop off and/or pick up storage containers <NUM> so that they can be transported to an access station (not shown) where the storage containers <NUM> can be accessed from ontside of the framework structure <NUM> or transferred out of or into the framework structure <NUM>. For example, the storage containers <NUM> may be placed in a random or a dedicated column <NUM> within the framework structure <NUM>, then picked up by any container handling vehicle and transported to a port column <NUM>, <NUM> for further transportation to an access station. The transportation from the port to the access station may require movement along various different directions, by means such as delivery vehicles, trolleys or other transportation lines.

In <FIG>, the first port column <NUM> may for example be a dedicated drop-off port column where the container handling vehicles <NUM>, <NUM> can drop off storage containers <NUM> to be transported to an access or a transfer station, and the second port column <NUM> may be a dedicated pick-up port column where the container handling vehicles <NUM>, <NUM>, <NUM> can pick up storage containers <NUM> that have been transported from an access or a transfer station.

The access station may typically be a picking or a stocking station where product items are removed from or positioned into the storage containers <NUM>. In a picking or a stocking station, the storage containers <NUM> are normally not removed from the automated storage and retrieval system <NUM>, but are, once accessed, returned into the framework structure <NUM>. 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.

A conveyor system comprising conveyors is normally employed to transport the storage containers between the port columns <NUM>, <NUM> and the access station.

If the port columns <NUM>, <NUM> and the access station are located at different heights, the conveyor system may comprise a lift device with a vertical component for transporting the storage containers <NUM> vertically between the port column <NUM>, <NUM> and the access station
The conveyor system may be arranged to transfer storage containers <NUM> between different framework structures, e.g. as is described in <CIT>.

When a storage container <NUM> stored in one of the columns <NUM> disclosed in <FIG> is to be accessed, one of the container handling vehicles <NUM>, <NUM>, <NUM> is instructed to retrieve the target storage container <NUM> from its position and transport it to the drop-off port column <NUM>. This operation involves moving the container handling vehicle <NUM>, <NUM> to a location above the storage column <NUM> in which the target storage container <NUM> is positioned, retrieving the storage container <NUM> from the storage column <NUM> using the container handling vehicle's <NUM>, <NUM>, <NUM> lifting device (not shown), and transporting the storage container <NUM> to the drop-off port column <NUM>. Alternatively, or in addition, the automated storage and retrieval system <NUM> may have container handling vehicles <NUM>, <NUM>, <NUM> specifically dedicated to the task of temporarily removing storage containers <NUM> from a storage column <NUM>. Once the target storage container <NUM> has been removed from the storage column <NUM>, the temporarily removed storage containers <NUM> can be repositioned into the original storage column <NUM>. However, the removed storage containers <NUM> may alternatively be relocated to other storage columns <NUM>.

When a storage container <NUM> is to be stored in one of the columns <NUM>, one of the container handling vehicles <NUM>, <NUM>, <NUM> is instructed to pick up the storage container <NUM> from the pick-up port column <NUM> and transport it to a location above the storage column <NUM> where it is to be stored. After storage containers <NUM> positioned at or above the target position within the stack <NUM> have been removed, the container handling vehicle <NUM>, <NUM>, <NUM> positions the storage container <NUM> at the desired position. The removed storage containers <NUM> may then be lowered back into the storage column <NUM> or relocated to other storage columns <NUM>.

For monitoring and controlling the automated storage and retrieval system <NUM>, e.g. monitoring and controlling the location of respective storage containers <NUM> within the framework structure <NUM>, the content of each storage container <NUM> and the movement of the container handling vehicles <NUM>, <NUM>, <NUM> so that a desired storage container <NUM> can be delivered to the desired location at the desired time without the container handling vehicles <NUM>, <NUM>, <NUM> colliding with each other, the automated storage and retrieval system <NUM> comprises a control system <NUM> (shown in <FIG>) which typically is computerized and which typically comprises a database for keeping track of the storage containers <NUM>.

It is necessary for the above-described storage system to be even in the horizontal direction, at the floor level as well as at the top of framework structure level. This entails that the floor of the building should preferably be even since the horizontally extending floor rails (shown in <FIG>) that support the storage system are positioned directly on the floor. A framework structure <NUM> of <FIG>, comprising upright members <NUM>, rests on these floor rails. The members <NUM> support an upper rail system <NUM>.

Usually, floors of newly built facilities comply with the requirement that the floor needs to be even. However, when existing facilities are repurposed to house an automated storage and retrieval system, it is common that the floor of the facility has an irregular and/or sloping surface. In this context, lead time for installation of the system is normally limited. In consequence, the deficiencies of the floor are typically not remedied in connection with system installation. In a closely related context, there could be small discrepancies with respect to the length of the manufactured upright members <NUM> as well.

A known solution to this problem is described in <CIT>. More specifically, it is disclosed a leveling foot comprising a hollow column. A spring is arranged in the hollow column of the foot. A top piece engages the column and is movable in the vertical direction as a function of the spring force. In its other end, the top piece mates with the previously mentioned, upright member. The spring force causes top piece to extend so that any vertical gap at the upper rail system <NUM>, caused either by a depression in the floor surface or by the member <NUM> being too short, is compensated for. Once the top piece is in the desired position, the foot is immobilized by bringing a wedge device into locking engagement with the hollow column. The solution proposed in <CIT> performs adequately in situations involving smaller vertical gaps at the upper rail system.

Larger vertical gaps are typically addressed by manufacturing customized shims from sheet metal. These shims are subsequently inserted between the floor rail and the leveling foot where required. This process is relatively complex and timeconsuming.

In a related context, in cases where the storage system to be supported is particularly heavy, a floor rail-based structure that is initially level may, due to the weight of the system, create depressions in the floor surface. In these situations, it is desirable to provide a leveling solution enabling continuous level adjustment in order to compensate for post-installation settling caused by the weight of the storage system.

Documents <CIT>, <CIT>, <CIT> and <CIT> disclose further prior art systems.

In view of all of the above, it is desirable to provide a solution that solves or at least mitigates one or more of the aforementioned problems belonging to the prior art.

First aspect of the invention relates to a levelling assembly for a framework structure of a storage grid of a storage and retrieval system for storing goods holders, said framework structure being positioned on a floor surface. The levelling assembly comprises a threaded elongate member, a threaded nut for engaging with the threaded elongate member, a floor rail for supporting vertical members of the storage and retrieval system, the floor rail configured for positioning on the floor surface, wherein the floor rail is provided with a first aperture for mounting the threaded elongate member in a location on the floor rail where the member can extend through the floor rail and be coupled to said floor rail, wherein the floor rail is provided with a channel for receiving the threaded nut and extending from the aperture in a longitudinal direction of the floor rail, wherein in a first state of the levelling assembly, the threaded elongate member is in contact with the floor surface and engages with the threaded nut that is received in the channel and rotationally immobilized relative said channel so that, in response to a rotational force applied on the threaded elongate member, the floor rail is movable in vertical direction, wherein said floor rail is so configured that said threaded elongate member, when in contact with the floor surface and in engagement with the threaded nut received in the channel, protrudes beyond an upper face of the floor rail.

By providing the levelling assembly as defined above, a simple and cost-efficient solution for taking up irregularities in the floor surface is obtained. This also means that no specific training is necessary for the workers assigned to this particular moment of the system installation. In addition, the proposed solution is well-suited in situations where a large amount of assembly units needs to be adjusted in a short time period. Here, the adjustment of the levelling assembly may be effected by means of conventional tools, such as a wrench, a screwdriver or a hex key.

In addition, use of interacting threaded elements permits fine adjustments of the levelling assembly, i.e. adjustments in very small increments. This is particularly useful in situations requiring continuous adjustment of the levelling assembly. Moreover, the proposed solution may easily be implemented during installation of the storage and retrieval system. In a related context, the solution is compatible with the existing design of the storage and retrieval system for storing goods holders such that it is possible, subject to certain structural modifications, to retrofit the existing systems with the levelling assembly of the invention.

Second aspect of the invention relates to a method for taking up irregularities in a floor surface supporting a storage and retrieval system for storing goods holders by means of a levelling assembly in accordance with claim <NUM>.

For the sake of brevity, advantages discussed above in connection with the levelling assembly may even be associated with the corresponding method and are not further discussed. Here, it is to be construed that the sequence of method steps of claim <NUM> may be effectuated in any given order.

For the purposes of this application, the term "container handling vehicle" used in "Background and Prior Art"-section of the application and the term "remotely operated vehicle" used in "Detailed Description of the Invention"-section both define a robotic wheeled vehicle operating on a rail system arranged across the top of the framework structure being part of an automated storage and retrieval system. Analogously, the term "storage container" used in "Background and Prior Art"-section of the application and the term "goods holder" used in "Detailed Description of the Invention"-section both define a receptacle for storing items. In this context, the goods holder can be a bin, a tote, a pallet, a tray or similar. Different types of goods holders may be used in the same automated storage and retrieval system.

The relative terms "upper", "lower", "below", "above", "higher" etc. shall be understood in their normal sense and as seen in a Cartesian coordinate system. When mentioned in relation to a rail system, "upper" or "above" shall be understood as a position closer to the surface rail system (relative to another component), contrary to the terms "lower" or "below" which shall be understood as a position further away from the rail system (relative another component).

The framework structure <NUM> of the automated storage and retrieval system <NUM> is constructed in accordance with the prior art framework structure <NUM> described above in connection with <FIG>, i.e. a number of upright members <NUM>, wherein the framework structure <NUM> also comprises a first, upper rail system <NUM> in the X direction and Y direction.

The framework structure <NUM> further comprises storage compartments in the form of storage columns <NUM> provided between the members <NUM> where storage containers <NUM> are stackable in stacks <NUM> within the storage columns <NUM>.

In particular, it is understood that the framework structure can be considerably wider and/or longer and/or deeper than disclosed in <FIG>.

Various aspects of the present invention will now be discussed in more detail with reference to <FIG>.

<FIG> is a perspective view of a plurality of mutually parallel rows of floor rails <NUM>. Perpendicular to these floor rails <NUM>, cross-members <NUM> serving as spacing elements are provided. The floor rails <NUM> extend in a first direction and the cross-members <NUM> extend in a second direction perpendicular to the first direction. The cross-members <NUM> cross over the floor rails <NUM> at cross-over points <NUM> to define a lattice structure that is to serve as the foundation for the framework structure shown in <FIG>.

<FIG> shows a perspective view of a section of an exemplary floor rail <NUM> in accordance with one embodiment of the present invention. Shown floor rail <NUM> has apertures <NUM>, <NUM> and a longitudinally extending T-shaped slot <NUM> on its upper face, the T-shaped slot <NUM> communicating with at least one of the apertures <NUM>, <NUM>. Apertures <NUM>, <NUM> delimit a central section <NUM> of the floor rail <NUM>. It is in the delimited section an upright member (<NUM>; shown in <FIG>) is connected to the floor rail <NUM> by means of a levelling foot of the type discussed in Background and Prior Art-section (shown in <FIG>). The foot and the upright member are arranged midway between the first <NUM> and the second <NUM> apertures.

<FIG> is a close-up view of a section of a floor rail shown in <FIG>. In addition to apertures <NUM>, <NUM>, the floor rail <NUM> has further holes <NUM> for mounting the levelling foot mentioned above. The floor rail <NUM> of <FIG> further comprises a first <NUM> and a second recess <NUM> communicating with the respective aperture <NUM>, <NUM> and with the T-shaped slot <NUM>. The first <NUM> and the second <NUM> recesses extend in a direction of extension of the T-shaped slot <NUM>, are aligned and oppositely arranged.

<FIG> is a perspective view showing a floor rail <NUM> of the type discussed in connection with <FIG>, a leveling foot <NUM> and a section of a thereto associated upright member <NUM>.

<FIG> is an exploded view of a threaded elongate member <NUM>, a threaded nut <NUM> for engagement with the threaded member and a base member <NUM>. In the shown embodiment, the threaded elongate member <NUM> is a bolt having a socket cap head. In an alternative embodiment, such a bolt could have a conventional hex head. Accordingly, the adjustment may be effected by means of conventional tools, such as a wrench, a screwdriver or a hex key.

Still with reference to <FIG>, the base member <NUM> is detachable and provided with a hole <NUM> for receiving the threaded elongate member <NUM>. The hole <NUM> of the base element <NUM> could be at least partially threaded. As will be shown in connection with <FIG>, in use, the base member <NUM> is positioned on the floor surface, in a cavity delimited by the walls of the floor rail <NUM> and the floor.

<FIG> is a connected view of the members of <FIG>, ready to be deployed, i.e. brought in engagement with the floor rail. This will be discussed in greater detail in connection with <FIG>.

In an alternative embodiment, shown in <FIG>, base member is a foot member <NUM> connected to an end of the threaded elongate member <NUM>. The threaded elongate member <NUM> lacks a conventional head and is actuated by means of a screwdriver. The foot member <NUM> could be compressible in a vertical direction, for instance by making lowermost portion <NUM> of the foot in a polymer material, such as rubber. This would also improve friction properties of the foot member <NUM>. In one embodiment, connection means between the threaded elongate member <NUM> and the foot member <NUM> is a ball joint <NUM>. In this way, the foot member <NUM> may accommodate local unevenness, for instance slanting, of the floor surface. A threaded nut of <FIG> may be employed with the threaded elongate member/foot member of <FIG>.

<FIG> is close-up of an entire inventive assembly prior to engagement, whereas <FIG> is close-up of the inventive assembly of <FIG>, where the elongate member <NUM> and the nut member <NUM> are in engagement with the floor rail <NUM>.

Accordingly, it is shown in <FIG> a levelling assembly for a framework structure of a storage grid of a storage and retrieval system for storing goods holders. In other words, the assembly provides a flat and even surface for operation of remotely operated vehicles shown in <FIG>. The framework structure is positioned on a floor surface. The levelling assembly comprises previously discussed components - a threaded elongate member <NUM>, a threaded nut <NUM> for engaging with the threaded elongate member <NUM>, and a floor rail <NUM> for supporting upright members <NUM> of the storage and retrieval system <NUM>. As discussed above, the floor rail <NUM> is provided with a first aperture <NUM> for mounting the threaded elongate member <NUM> in a location on the floor rail <NUM> where the member <NUM> can extend through and be coupled to said floor rail <NUM>. The floor rail is provided with a channel <NUM>, typically a T-shaped slot, for receiving the threaded nut <NUM> and extending from the aperture <NUM> in a longitudinal direction of the floor rail. A base member <NUM> ensuring floor contact of the threaded elongate member <NUM> is also shown.

Still with reference to <FIG>, the threaded elongate member <NUM> is engaged with the threaded nut <NUM> and these are subsequently inserted into the first aperture <NUM> arranged in said floor rail <NUM>. Thereafter, the threaded nut <NUM> is arranged in the channel <NUM> extending from the aperture <NUM> in a longitudinal direction of the floor rail <NUM> by sliding the threaded elongate element <NUM> engaged with the threaded nut <NUM> into the channel <NUM> of the floor rail <NUM> so that the threaded nut <NUM> is rotationally immobilized relative the channel <NUM>.

Turning now to <FIG>, in a first state of the levelling assembly <NUM>, the threaded elongate member <NUM> is in contact with the floor surface, via the base member, and engages with the threaded nut <NUM> that is received in the channel <NUM>. The threaded nut <NUM> is dimensioned to fit tightly in the channel <NUM> and is rotationally immobilized relative said channel <NUM> so that, in response to a rotational force applied on the threaded elongate member <NUM>, the floor rail <NUM> is movable in vertical direction, i.e. it may be raised and lowered.

By providing the levelling assembly <NUM> as defined above, a simple and cost-efficient solution for taking up irregularities in the floor surface is obtained. This also means that no specific training is necessary for the workers assigned to this particular moment of the system installation. In addition, the proposed solution is well-suited in situations where a large amount of units needs to be adjusted in a short time period.

In addition, use of interacting threaded elements <NUM>, <NUM> permits fine adjustments of the levelling assembly <NUM>, i.e. adjustments in very small increments. This is particularly useful in situations requiring continuous adjustment of the levelling assembly <NUM>.

In an embodiment, the levelling assembly <NUM> is locked in an adjusted position (second state of the levelling assembly) by immobilizing the threaded elongate member <NUM> in vertical direction by means of a locknut (not shown) engaging with the threaded elongate member <NUM> and abutting against the floor rail <NUM>.

<FIG> is a cross-sectional view with the inventive assembly <NUM> shown in <FIG>. The solution includes two levelling assemblies <NUM>, one on each side of the upright member <NUM>. For the sake of intelligibility and completeness, parts of the levelling assembly <NUM> are provided with reference numerals corresponding to those employed in connection with <FIG>. The levelling foot <NUM> is also shown.

As easily inferred from above, the proposed solution may easily be implemented during installation of the storage and retrieval system <NUM>. In a related context, the solution is compatible with the existing design of the storage and retrieval system for storing goods holders such that it is possible, subject to structural modifications, to retrofit the claimed levelling assembly <NUM> on existing systems.

Claim 1:
A levelling assembly (<NUM>) for a framework structure of a storage grid of a storage and retrieval system (<NUM>) for storing goods holders (<NUM>), said framework structure being positioned on a floor surface, said levelling assembly (<NUM>) comprising:
- a threaded elongate member (<NUM>),
- a threaded nut (<NUM>) for engaging with the threaded elongate member (<NUM>),
- a floor rail (<NUM>) for supporting upright members (<NUM>) of the storage and retrieval system (<NUM>), said floor rail configured for positioning on the floor surface, wherein the floor rail (<NUM>) is provided with a first aperture (<NUM>) for mounting the threaded elongate member (<NUM>) in a location on the floor rail where the member (<NUM>) can extend through the floor rail (<NUM>) and be coupled to said floor rail (<NUM>), wherein the floor rail is provided with a channel (<NUM>) for receiving the threaded nut (<NUM>) and extending from the aperture (<NUM>) in a longitudinal direction of the floor rail (<NUM>), wherein,
in a first state of the levelling assembly (<NUM>), the threaded elongate member (<NUM>) is in contact with the floor surface and engages with the threaded nut (<NUM>) that is received in the channel (<NUM>) and rotationally immobilized relative said channel (<NUM>) so that, in response to a rotational force applied on the threaded elongate member (<NUM>), the floor rail (<NUM>) is movable in vertical direction, wherein
said floor rail is so configured that said threaded elongate member (<NUM>), when in contact with the floor surface and in engagement with the threaded nut (<NUM>) received in the channel (<NUM>), protrudes beyond an upper face of the floor rail (<NUM>).