Patent Description:
The members <NUM>, <NUM> may typically be made of metal, e.g. extruded aluminium profiles.

The framework structure <NUM> of the automated storage and retrieval system <NUM> comprises a rail system <NUM> arranged in a grid pattern across the top of the framework structure <NUM>, on which rail system <NUM> a plurality of container handling vehicles <NUM>,<NUM> are 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 horizontal extent of one of the grid cells <NUM> constituting the grid pattern is marked by thick lines.

The rail system <NUM> (i.e. a rail grid) 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. Commonly, at least one of the sets of rails <NUM>,<NUM> is made up of dual-track rails allowing two container handling vehicles to pass each other on neighbouring grid cells <NUM> Dual-track rails are well-known and disclosed in for instance <CIT> and <CIT>.

Each prior art container handling vehicle <NUM>,<NUM> also comprises a container lifting assembly <NUM> (shown in <FIG>) 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 container lifting assembly <NUM> comprises a lifting frame <NUM> having one or more gripping/engaging devices <NUM> adapted to engage a storage container <NUM> and guide pins <NUM> for correct positioning of the lifting frame <NUM> relative to the storage container <NUM>. The lifting frame <NUM> can be lowered from the vehicle <NUM>,<NUM> by lifting bands <NUM> so that the position of the lifting frame with respect to the vehicle <NUM>,<NUM> can be adjusted in a third direction Z which is orthogonal the first direction X and the second direction Y.

The lifting frame <NUM> (not shown) of the container handling vehicle <NUM> in <FIG> is located within a cavity of the vehicle body 201a.

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.

The central 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'.

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 returned into the framework structure <NUM> 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.

A conveyor system comprising e.g. belt or roller conveyors may be employed to transport the storage containers between the port columns <NUM>,<NUM> and the access station.

Belt and/or roller conveyors are relatively expensive and often service intensive. To avoid use of such conveyors, some access stations may have a section arrangeable directly below a port column such that a storage container may be transferred directly to the access station. Prior art access stations suitable for being arranged below a port column are disclosed in for example <CIT> and <CIT>. The prior art access stations may move a storage container from a position below a port column to a picking/stocking position (or access position) by a radial movement around a rotational axis. An operator has access to the content of the storage container at the picking/stocking position. Due to the space required for performing the radial movement, the minimum width of the prior art access stations at the picking/stocking position is about twice the width of a storage container. Thus, the radial movement of the prior art access stations disclosed in <CIT> and <CIT> may in some cases be disadvantageous. For instance, multiple picking/stocking positions may not be arranged adjacent to each other, since the access stations have a relatively large footprint at the outside of the framework structure and the positioning of the picking position relative to the port column is quite inflexible. Further, the placement of the prior art access stations is somewhat inflexible since the distance from a port column to a picking/stocking position is set by the extent of the radial movement.

The access station disclosed in <CIT> features a storage container holder and a complex guide mechanism for tilting the storage container holder towards an operator to provide an ergonomically improved work position.

<CIT>, which the EPO identified as the 'closest prior art', describes a picking/supply station with storage bin holding devices. During use a storage bin is transferred from a storage system grid, for instance by use of a bin lift, to a port in the picking/supply station. The bin holding device features a base plate and two vertical side elements. The side elements are arranged at opposite side edges of the base plate, and are spaced to accommodate a storage bin between them. Each of the side elements features two bin supporting assemblies comprising a bin support element and an actuator lever. The bin supporting assembly is connected at the side element via a bracket. The bracket features through holes in which the supporting assembly is pivotably mounted. A top surface of the bin support element is arranged to interact with a downwards facing surface of an external side edge arranged on the sidewall of the storage bin. By supporting the storage bin via the external side edge, a top edge of the storage bin is always held at a predetermined level relative the base plate of the device, provided the level of the surface is kept constant relative the top edge on all storage bins to be used with the bin holding device. In this manner the level of the top edge, when accommodated in the bin holding device, will be independent of the height of the storage bin. During introduction of the storage bin, a bottom edge of the storage bin will push the actuator levers in a horizontal direction away from the storage bin. Each of the actuator levers is pivotably connected to a corresponding bin support element, such that the horizontal movement of the actuator levers provides a similar and opposite direction movement of the top surface of the bin support element. The movement of the actuator levers causes the bin support elements to be positioned such that the lower surface of the edge will rest upon the surfaces of the bin support elements when fully accommodated in the bin holding device. Each of the bin supporting assemblies is pretensioned/biased by a spring such that the actuator levers return to their non-actuated position when the storage bin is lifted off, or out of, the bin holding device. The bin support element is moved between an inactive position to an active position. In the active position, at least the top surfaces of the bin support elements is moved closer to each other, or in other words, closer to the storage bin accommodated between the side elements.

<CIT> describes an automated storage and retrieval system, a storage container handling vehicle and a method for operating such a system. The system comprises one or more vehicles configured to lift and move storage containers stacked in the system. Each vehicle comprises a storage container lifting device, a drive system with a wheel arrangement configured to drive and manoeuvre the vehicle along the track system, a base onto which the wheel arrangement is connected, a rotational part rotationally connected via a swivel device to the base and a rotational drive system for rotating the rotational part relative to the base.

When a storage container <NUM> is to be stored in one of the columns <NUM>, one of the container handling vehicles <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 any storage containers positioned at or above the target position within the storage column stack <NUM> have been removed, the container handling vehicle <NUM>,<NUM> positions the storage container <NUM> at the desired position. The removed storage containers may then be lowered back into the storage column <NUM> or relocated to other storage columns.

An object of the present invention is to provide an improved access station, wherein at least some of the disadvantages of the prior art access stations utilizing a radial movement of the container holders are alleviated or minimized.

The present invention is defined by an access station according to claim <NUM>.

Embodiments of the invention become apparent from the dependent claims.

In a first example useful for understanding the present invention, a container handling module for an access station in a storage system is provided, the container handling module comprises a first container holder, a second container holder, a shuttle and a rail assembly, the first and second container holders are rotatably mounted to the shuttle via a rotary shaft, wherein each of the first and second container holders is arranged to accommodate a storage container and is rotatable around an axis of rotation between a first angular position and a second angular position, the second angular position being opposite the first angular position relative to a centreline of the rotary shaft, and the shuttle being configured for linear movement in a horizontal direction between a first linear position and a second linear position relative to the rail assembly.

The first and second container holders may be in the form of a tray. In other embodiments of said first example, the container holders may feature a belt or roller conveyor allowing a storage container to be loaded on/off a container holder in a horizontal direction, e.g. to/from an external conveyor system. The first and second container holders may have the same shape and configuration, arranged opposite one another relative to the centreline of the rotary shaft.

In an embodiment of said first example, the rail assembly may comprise two parallel rails and a support framework, i.e. a framework for supporting the rails.

In an embodiment of said first example, the first and second container holders extend laterally beyond the parallel rails during rotation between the first and second angular position.

In an embodiment of said first example, the first and second container holders extend further laterally beyond the parallel rails during rotation between the first and second angular position than in the first and second angular position.

In an embodiment of said first example, the shuttle may be configured for linear movement in a horizontal direction between a first linear position and a second linear position relative to the rail assembly, such that the first or second container holder arranged in the first angular position, when the shuttle is in the first linear position, may be moved by the shuttle to occupy a space corresponding to a space that was occupied by the first or second container holder arranged in the second angular position when the shuttle was in the first linear position, without rotation around the axis of rotation.

In an embodiment of said first example, the shuttle may be configured for linear movement in a horizontal direction between a first linear position and a second linear position relative to the rail assembly, such that the placement of any of the first and second container holders in the first angular position and the second angular position may be moved relative to the rail assembly.

In an embodiment of said first example, the shuttle may comprise a set of wheels in contact with the rail assembly and configured to allow movement of the shuttle in the horizontal direction between the first linear position and the second linear position relative to the rail assembly. In other words, the set of wheels may be configured to move the shuttle and the first and second container holders in the horizontal direction.

In an embodiment of said first example, each of the two parallel rails may have a cross-section comprising guide surfaces, the guide surfaces arranged to interact with the shuttle to restrict vertical movement of the shuttle relative to the rail assembly. In other words, the guide surfaces are arranged to prevent or restrict tilting of the shuttle relative to the rails and/or framework. The guide surfaces may be longitudinal and parallel to the rails. The guide surfaces may for instance interact with the set of wheels, ribs or recesses on the shuttle, and/or ribs or recesses on the wheel shafts of the set of wheels. The guide surfaces comprises at least a downwards facing surface.

In an embodiment of said first example, each of the two parallel rails may have a cross-section comprising guide surfaces provided by an upper flange and a lower flange for interaction with the set of wheels, the upper and lower flanges are arranged to restrict vertical movement of the set of wheels relative to the rail assembly. They may also help to restrict lateral movement perpendicular to the direction of travel of the container handling module, to help guide forward and back movement of the container handling module. The upper flange comprises a downwards facing guidesurface.

In an embodiment of said first example, the shuttle may move between a first end and a second end of the rail assembly.

In an embodiment of said first example, the first or second container holder being in the first angular position may be arranged at the first end of the rail assembly when the shuttle is in the first linear position. The length of the horizontal movement of the shuttle between the first linear position and the second linear position may be at least equal to a minimum extent of the first or the second container holder in the horizontal plane.

In an embodiment of said first example, either the first or the second container holder being in the first angular position is arranged at the first end of the rail assembly when the shuttle is in the first linear position.

In an embodiment of said first example, the first angular position is arranged between the first end of the rail assembly and the axis of rotation.

In an embodiment of said first example, either the first or the second container holder arranged in the first angular position may be closer to the first end of the rail assembly than the other of the first or the second container holder arranged in the second angular position, i.e. when the shuttle is in a set linear position.

In an embodiment of said first example, the shuttle may move linearly for a distance being at least equal to a horizontal distance between the axis of rotation and a distal portion of the first container holder or the second container holder. In other words, the linear movement of the shuttle may extend for a distance being at least equal to a horizontal distance between the axis of rotation and a distal portion of the first container holder or the second container holder.

In an embodiment of said first example, the length of the rail assembly in the horizontal direction may be at least three times a horizontal distance between the axis of rotation and a distal portion of either the first container holder or the second container holder. In a further embodiment, the length of the rail assembly in the horizontal direction may be at least four times a horizontal distance between the axis of rotation and a distal portion of the first container holder or the second container holder.

In an embodiment of said first example, the distance between the first linear position and the second linear position may be at least equal to a horizontal distance between the axis of rotation and a distal portion of either the first container holder or the second container holder. In a further embodiment, the distance may be at least equal to twice the horizontal distance between the axis of rotation and a distal portion of the first container holder or the second container holder. The distal portion is intended to mean the portion of the first and second container holders being furthest removed from the axis of rotation.

In an embodiment of said first example, the first container holder may be arranged opposite of the second container holder relative to the axis of rotation. In other words, the first and second container holders may be positioned on opposite sides of the axis of rotation, such that the first or second container holder is in the first angular position when the other container holder is in the second angular position.

In an embodiment of said first example, the container handling module may comprise a first electric motor arranged to rotate the first and second container holders around the axis of rotation and/or a second electric motor arranged to move the shuttle between the first linear position and the second linear position. The second electric motor may be arranged to rotate at least one wheel of the set of wheels. The rotation of the at least one wheel of the set of wheels may be obtained by rotational engagement of the wheel to the second electric motor or by having the second electric motor arranged to move the shuttle in a linear direction.

In an embodiment of said first example, the shuttle may move to at least one intermediate linear position arranged between the first linear position and the second linear position.

In an embodiment of said first example, the axis of rotation may be inclined at a first angle relative to a vertical, and each of the first container holder and the second container holder is configured such that a centreline of an accommodated storage container when supported by the respective container holder is inclined at a second angle relative to the axis of rotation, wherein the centreline of an accommodated storage container is vertical when in the second angular position and inclined at a third angle relative to the vertical when in the first angular position, the third angle being equal to the sum of the first angle and the second angle.

The centreline of a storage container is intended to define a line being perpendicular to a plane of the storage container bottom and intersecting the centre of said bottom. Alternatively, the centreline of a storage container may be defined as the central axis of the storage container. When supported on a container holder arranged in the second angular position, a centreline of the storage container may extend perpendicular to a horizontal line extending between the first and second angular positions.

In an embodiment of said first example, the centreline of a storage container may coincide with a centreline of the first or second container holder on which the storage container is accommodated. In other words, the axis of rotation may be inclined at a first angle relative to a vertical, and each of the first container holder and the second container holder is configured such that a centreline of the respective container holder is inclined at a second angle relative to the axis of rotation, wherein the centreline of any of the first and second container holder is vertical when in the second angular position and inclined at a third angle relative to the vertical when in the first angular position, the third angle being equal to the sum of the first angle and the second angle.

In other words, when the axis of rotation is inclined, any of the first and second container holders may rotate/orbit <NUM> degrees about the axis of rotation between a second angular position, wherein an accommodated storage container is horizontal, i.e. has an opening facing directly upwards, and a first angular position, wherein an accommodated storage container is inclined at the third angle relative to the vertical, i.e. has an opening facing upward and inclined at the third angle relative to the vertical. The first angle may be substantially equal to the second angle. In the present specification, the term "substantially equal" is intended to mean that the size of the first angle differs from the size of the second angle by less than <NUM>%, and preferably less than <NUM>%.

In an embodiment of said first example, the first angle and the second angle may each be within a range of <NUM>-<NUM> degrees, <NUM>-<NUM> degrees or <NUM>-<NUM> degrees.

In an embodiment of said first example, the centreline of a storage container accommodated in either the first or second container holder may be inclined relative to a vertical when the respective container holder is in the first angular position, such that an opening of the storage container will face away from the axis of rotation. In other words, when the container holder is in the first angular position, a top opening of an accommodated storage container may be inclined in order to face an operator when the container handling module is part of an access station.

In an embodiment of said first example, the axis of rotation may be inclined towards the first end of the rail assembly.

In an embodiment of said first example, the centreline of a storage container accommodated by the first or second container holder may be gradually inclined from the vertical to the third angle during an arcuate movement between the second angular position and the first angular position.

In a first aspect, an access station comprising at least one container handling module according to any embodiment of said first example, is provided, wherein the container handling module is arranged to present a storage container at an access position of the access station, at which access position an operator or robot may have access to the storage container when the storage container is supported by either the first or the second container holder being in the first angular position and the shuttle is in the first linear position. In other words, either of the first or the second container holders may be arranged at an access position, when the respective container holder is in the first angular position and the shuttle is in the first linear position.

In an embodiment of the access station, the container handling module is arranged to allow a storage container to be provided to or retrieved from either of the first or the second container holder, when the respective container holder is in the second angular position and the shuttle is in the second linear position. In other words, any of the first and second container holders may be arranged at a storage container loading/unloading position, when the respective container holder is in the second angular position and the shuttle is in the second linear position.

In an embodiment of the access station, the container handling module may be arranged to allow a storage container to be provided to or retrieved from the first or the second container holder, when the respective container holder is in the second angular position and the shuttle is in any of the first linear position and the second linear position.

In an embodiment of the access station, the first and second container holder may rotate around the axis of rotation when the shuttle is in the second linear position. In other words, the first and second container holder have room or space to rotate around the axis of rotation at least when the shuttle is in the second linear position.

In an embodiment, the access station may comprise a cabinet within which the first end of the rail assembly of the at least one container handling module is arranged, the cabinet comprises an access opening arranged to be aligned with the access position.

In an embodiment, the access station may comprise a first container handling module and a second container handling module, wherein the rail assemblies of the first and second container handling modules are arranged in parallel, or perpendicular to each other, to provide two adjacent access positions.

In an embodiment, the access station may be configured for a storage system featuring at least one port column, through which port column storage containers may be transferred in a vertical direction, and wherein the access station comprises a station framework configured for supporting the lower end of the at least one port column above the rail assembly. In other words, the station framework is configured such that a storage container may be provided or retrieved from any of the first and second container holders via the at least one port column, when the respective container holder is in the second angular position and the shuttle is in any of the first linear position and the second linear position depending on which linear position the at least one port column is arranged above. The station framework may comprise horizontal beams, e.g. lintels, upon which the lower end of the at least one port column is supported. The framework may also comprise vertical uprights for supporting the horizontal beams. The station framework is configured to support the lower end of the at least one port column at a level above an upper level of a storage container arranged on any of the first and second container holders.

In an embodiment, the access station may be configured for a storage system having a plurality of port columns, and the station framework is configured for supporting the lower ends of the plurality of port columns above the rail assembly. In other words, the station framework is configured for supporting the lower ends of the plurality of port columns at separate port column positions arranged above and along the rail assembly. Each of the separate port column positions may be aligned with a respective container holder position that may be occupied by the first or second container holder depending on the angular position of the container holder and the linear position of the shuttle.

In an embodiment of the access station, the first container holder and the second container holder of the first container handling module may rotate around the axis of rotation when the shuttle of the first container handling module is in the second linear position and the shuttle of the second container handling module is in the first linear position.

In an embodiment of the access station, the station framework is arranged to provide sufficient space for rotation of the first container holder and the second container holder of the at least one container handling module around the axis of rotation when the shuttle of the at least one container handling module is in the second linear position. The framework may in some embodiments provide sufficient space for rotation of the first container holder and the second container holder of the at least one container handling module around the axis of rotation when the shuttle of the at least one container handling module is in the first linear position.

In a second aspect, a storage system comprising an access station according to any embodiment of the first aspect is provided, wherein the storage system features at least one port column through which port column storage containers may be transferred in a vertical direction, the at least one port column is arranged above the rail assembly of the at least one container handling module of the access station such that a storage container may be delivered to, or retrieved from, the first or second container holder via the port column when the first or second container holder is arranged in the second angular position and the shuttle is in the second linear position.

In an embodiment, the storage system may comprise a plurality of port columns arranged above the rail assembly of the at least one container handling module of the access station such that a storage container may be delivered to, or retrieved from, the first or second container holder via a port column when the first or second container holder is arranged in the second angular position and the shuttle is in any of the first linear position and the second linear position. The plurality of port columns, for example, arranged in a row and comprising, say, two, three or four port columns, may allow different types of container handling vehicles to use the access station, for example, cantilever-style container handling vehicles with cantilevers extending in different directions as well as allowing multiple container handling vehicles to drop off storage containers to or retrieve storage containers from the access station at the same time.

In an embodiment of the storage system, the shuttle of the at least one container handling module may move to at least one intermediate linear position arranged between the first linear position and the second linear position, wherein the storage system comprises a plurality of port columns arranged above the rail assembly of the at least one container handling module such that a storage container may be delivered to, or retrieved from, the first or second container holder when the first or second container holder is arranged in the second angular position and the shuttle is in any of the intermediate linear position and the second linear position.

In an embodiment of the storage system, the storage system or the access station may comprise a station framework configured for supporting the lower ends of the plurality of port columns above the rail assembly.

In an embodiment, the storage system comprises vertical column profiles defining a plurality of grid columns, the grid columns comprise storage columns in which storage containers can be stored one on top of another in vertical stacks, and at least one of the grid columns is a port column, each of the grid columns being defined by four vertically extending column profiles, and the column profiles are interconnected at their upper ends by top rails forming a horizontal top rail grid (or rail system) of the storage grid. The storage system may comprise a plurality of container handling vehicles arranged upon the top rail grid and configured to transfer storage containers from and to the top rail grid via the port columns.

In a second example useful for understanding the present invention, a method of exchanging a storage container at an access position of an access station according to any embodiment of the second aspect is provided, the method comprising the steps of:.

In a third aspect, a method of presenting a storage container for access at an access station according to any embodiment of the first aspect is provided, the method comprising the steps of:.

The first and second linear positions, between which the shuttle of the first container handling module may move, may be arranged adjacent to the respective first and second linear positions, between which the shuttle of the second container handling module may move.

In an embodiment, the method according to the third aspect may comprise the further steps of:.

In a third example useful for understanding the present invention, a method of presenting a storage container for access at an access station according to any embodiment of the first aspect is provided, the method comprising the steps of:.

Embodiments of the invention is described in detail by reference to the following drawings:.

However, the drawings are not intended to limit the invention to the subject-matter depicted in the drawings.

The container handling module and access station were developed for use in a prior art storage system as shown in <FIG> and described in detail above. However, both the container handling module and access station may advantageously be used in any type of container handling system, including various container storage systems, wherein access to a container is required.

A first exemplary container handling module <NUM> is shown in <FIG> and a second exemplary container handling module <NUM>' is shown in <FIG>. The container handling modules are suitable for use in storage system access stations. In an access station, a storage container may be transferred between a delivery/retrieval position at which the storage container may be delivered to or retrieved from the access station and an access position wherein a picker, i.e. a human operator or robot, may access the storage container.

The container handling module <NUM> comprises a first container holder 8a, a second container holder 8b, a shuttle <NUM> and a rail assembly featuring two parallel rails <NUM> and a support framework <NUM>. The first and second container holders 8a,8b are rotatably mounted to the shuttle <NUM> via a rotary shaft <NUM>. Each of the first and second container holders 8a,8b is arranged to accommodate a storage container <NUM>, see <FIG>, and is rotatable around an axis of rotation C between a first angular position P1 and a second angular position P2. The second angular position P2 is opposite of the first angular position P1 relative to a centreline C of the rotary shaft <NUM>. The first container holder 8a is arranged opposite of the second container holder 8b relative to the axis of rotation C, such that the first container holder 8a is in the first angular P1 position when the second container holder 8b is in the second angular position P2.

The shuttle <NUM> has a set of wheels <NUM> in contact with the two parallel rails <NUM> and is configured to allow linear movement of the shuttle <NUM> in the horizontal direction H between a first linear position L1 at a first end <NUM> of the rail assembly <NUM>,<NUM>, at least one intermediate linear position L2' and a second linear position L2 at a second end of the rail assembly <NUM>,<NUM>, i.e. the shuttle <NUM> may move linearly relative to the rail assembly.

When one of the first and second container holders 8a,8b is arranged in the first angular position P1 the respective container holder is arranged at or close to the first end <NUM> of the rail assembly when the shuttle <NUM> is in the first linear position L1.

The rail assembly <NUM>,<NUM> and shuttle <NUM> are configured to allow a first or second container holder arranged in the second angular position P2 to be moved linearly between two distinct positions relative to the rail assembly <NUM>,<NUM>, i.e. the horizontal periphery of the first container holder arranged in a first distinct position will not overlap with the horizontal periphery of the first container holder arranged in a second distinct position. In the embodiment shown in <FIG>, the distance between two distinct positions, e.g. the first linear position L1 and the intermediate linear position L2', is about equal to the distance between the axis of rotation C and a distal edge <NUM> (i.e. a distal portion) of any of the first container holder 8a and the second container holder 8b.

In the exemplary embodiment, the container holders 8a,8b are in the form of trays configured to support the bottom of a storage container. The trays are connected to the rotary shaft <NUM> by an angled beam <NUM>. The trays may also be configured to restrict transverse movement of the storage container relative to the trays. In other embodiments, the container holders may for instance be similar to the ones disclosed in <CIT>. Each of the container holders may also be rotatable about an internal axis as shown in <CIT>. In further alternate embodiments, the container holders may e.g. feature a belt or roller conveyor configured to transport a storage container on/off the container holder in a horizontal direction.

To enable stable rotation of the first and second container holders 8a,8b around the axis of rotation C, each of the two parallel rails <NUM> has a cross-section comprising an upper flange 22a, having a downwards facing guide surface <NUM>, and a lower flange 22b for interaction with the set of wheels <NUM>, the upper and lower flanges 22a,22b are arranged to restrict vertical movement of the set of wheels relative to the rail assembly. This feature is highly advantageous when the loads on the oppositely arranged container holders are uneven. Without the upper flanges 22a, i.e. guide surfaces, a narrow shuttle as disclosed in the present invention would easily tilt or tip over during rotation of the container holders between the first and second angular position.

To enable the required rotational and linear movements, the container handling module may feature a first electric motor <NUM> configured to rotate the first and second container holders 8a,8b around the axis of rotation C. Further, a second electric motor <NUM> may be arranged to rotate at least one wheel of the set of wheels <NUM>. Alternative embodiments are envisioned, wherein the second electric motor may be separate from the shuttle, e.g. arranged or connected at a section of the rail assembly to move the shuttle via a suitable drive band or linear actuator. The rotary shaft <NUM> is operatively connected to the electrical motor <NUM> via a drive band <NUM>. Other arrangements for connecting the rotary shaft <NUM> to an electrical motor are envisioned, for example, by gears or by use of direct drive motors. Electric power for driving the first electric motor <NUM> and/or the second electric motor <NUM> is provided by a power cable arranged within cable protector drag chain <NUM>.

The axis of rotation C, or the centreline of the rotary shaft <NUM>, may be inclined at a first angle X with respect to the vertical V, see <FIG>. The first and the second container holders 8a,8b are configured, and/or inclined, such that a centreline of an accommodated storage container <NUM> is inclined at a second angle Y relative to the axis of rotation C. In the exemplary embodiment, the centreline of an accommodated storage container will coincide with the centreline D of the respective container holder. The second angle Y is such that an opening of a storage container will face away from the axis of rotation C. In this specification, the centreline of a storage container <NUM> is a line being perpendicular to a plane of the storage container bottom and intersecting the centre of said bottom.

The result of having the axis of rotation C and the container holders 8a,8b configured, and/or inclined, such that an accommodated storage container is inclined at the respective first angle X and second angle Y is that a storage container is held horizontally when accommodated by a container holder in the second angular position P2 and inclined in the direction of the first end <NUM> of the rail assembly by an angle of X+Y (i.e. a third angle) when in the first angular position P1.

In the illustrated embodiment, the first angle X and the second angle Y are both <NUM> degrees, and the third angle is consequently <NUM> degrees. In other embodiments, the first angle X and the second angle Y will preferably be within the range of <NUM> to <NUM> degrees.

A common feature of the illustrated container holders is the presence of at least one container support surface upon which an accommodated storage container is supported, e.g. a bottom support surface <NUM> of the tray structure. The support surface(s) <NUM> will commonly be arranged in a support plane being parallel to the plane of the bottom of an accommodated storage container <NUM>. A line being perpendicular to the support plane will consequently be inclined at the same angle relative to the axis of rotation C as the centreline of an accommodated storage container. The inclination of the container holders, or the inclination of the support plane, may also be defined in relation to a radial plane perpendicular to the axis of rotation C by use of the second angle Y.

A second exemplary container holder module <NUM>' is shown in <FIG>. The differentiating feature of the container handling module compared to the embodiment in <FIG> is the way electric power is provided to the first and second electric motor <NUM>,<NUM>. In many applications it can be advantageous to increase the distance between an access position and a delivery/retrieval position. In the container handling modules the distance is decided by the length of the rail assembly <NUM>,<NUM> and the distance the shuttle <NUM> may travel upon the rail assembly <NUM>,<NUM>. In the first exemplary container holder module <NUM>, the travel distance of the shuttle <NUM> is restricted by the practical length of the cable protector drag chain <NUM>. To allow for an even longer travel distance of the shuttle <NUM>, power to the electric motors <NUM>,<NUM> of the second exemplary container holder module can be provided via contacts <NUM> on the rails and cooperating contacts <NUM> connected to e.g. a wheel shaft <NUM> of the shuttle <NUM>. In this way the travel distance of the shuttle is only restricted by efficiency considerations due to the increased travel time of the shuttle from a distal delivery/retrieval position to an access position, i.e. from the second linear position L2 to the first linear position L1. Structural elements making up the cooperating contacts <NUM> may also interact with guide surfaces <NUM> of the rails to restrict tilting of the shuttle.

An access station featuring the first exemplary container handling module <NUM> is shown in <FIG>. The access station is configured for use with a storage system as shown in <FIG>, and described above, and features a station framework <NUM> and a cabinet <NUM> with an access opening <NUM>. A first end <NUM> of the rail assembly <NUM>,<NUM> is arranged within the cabinet <NUM> such that a storage container <NUM> may be aligned with the access opening <NUM> when the shuttle <NUM> (<FIG>) is in the first linear position L1 and the storage container <NUM> is supported by one of the container holders 8a,8b arranged in the first angular position P1.

The shuttle <NUM> may move between a first linear position L1, an intermediate linear position L2' and a second linear position L2. The station framework is configured to support the lower ends of three port columns 119a-c arranged above the rail assembly <NUM>,<NUM>. In this manner, a storage container <NUM> may be provided or retrieved from any of the first and second container holders 8a,8b via one of the three port columns 119a-c, when the respective container holder is in the second angular position P2 and the shuttle <NUM> is in any of the first linear position L1, the intermediate linear position L2' and the second linear position L2.

The station framework <NUM> is configured to allow room for rotation of the first and second container holder 8a,8b around the axis of rotation C at least when the shuttle <NUM> is in the second linear position L2. The station framework may comprise lintels in the form of horizontal beams 34a upon which the lower end of at least one port column 119a-c of the storage system may be supported. Vertical uprights 34b may be used for supporting the horizontal beams 34a. The horizontal beams are configured to support the lower end of the port column at a level above an upper level of a storage container <NUM> arranged on any of the first and second container holder 8a.

A section of a storage system <NUM>' featuring an access station according to the invention is shown in <FIG>. The access station is similar to the one shown in <FIG> except that it comprises a second exemplary container handling module <NUM>' as shown in <FIG>.

The storage system features a first port column 119a, a second port column 119b and a third port column 119c, and each port column 119a-c has a lower end supported by the station framework <NUM> above the rail assembly <NUM>,<NUM>.

By using a plurality of port columns 119a-c, a storage container <NUM> may be delivered to, or retrieved from, the first or second container holder 8a,8b, via one of the port columns when the first or second container holder 8a,8b is arranged in the second angular position P2 and the shuttle <NUM> is in any of the first linear position L1, the intermediate linear position L2' and the second linear position L2.

Although the station framework <NUM> is shown as part of the access station in <FIG>, the station framework <NUM> may also be defined as a part of the framework structure <NUM>,<NUM> of the storage system itself. The footprint or width of the access station outside the framework structure <NUM> may be smaller than in the prior art access stations since the rotation of the container holders 8a,8b may be performed inside the framework structure. It is noted that the loss of storage space inside the framework structure due to the space required for rotation of the container holders is minimal since the columns arranged above the station framework are either port columns <NUM> or storage columns <NUM> (see <FIG>). The storage columns <NUM> supported by the station framework are provided with container stoppers (not shown) at their lower ends, such that each storage column <NUM> may accommodate a stack of storage containers above the station framework.

<FIG> illustrates an exemplary method of operating an access station (or storage system) according to the invention.

In <FIG>, a first storage container <NUM>' is presented at the access position <NUM> by having the first storage container <NUM>' supported on the first container holder 8a of the at least one container holder module <NUM>', the first container holder 8a is arranged in the first angular position P1, and the shuttle <NUM> is arranged in the first linear position L1. Any required picking/stocking of items from/to the first storage container is performed by a human operator or robot.

The shuttle <NUM> is then moved to the second linear position L2. A second storage container <NUM>'' is loaded onto the second container holder 8b when arranged in the second angular position P2 and the first and second container holder are rotated around the axis of rotation C to arrange the first container holder 8a in the second angular position P2 and the second container holder 8b in the first angular position P1. <FIG> shows the first storage container <NUM>' being unloaded from the first container holder 8a by use of a container handling vehicle <NUM> operating on the rail system <NUM>. In <FIG> and <FIG>, the shuttle <NUM> is moved towards the first linear position L1 in which the second storage container <NUM>" may be presented at the access position <NUM>. The combination of the rotational and linear movements of the container holders 8a,8b provides a highly flexible access station, wherein storage containers <NUM> may be retrieved or delivered to any of the container holders in any preferred sequence that provides the most efficient presentation and exchange of storage containers at the access position <NUM>. In addition, one of the storage containers may hold a frequently picked item and this arrangement of the container handling module <NUM> / access station may allow repeated picking of the item for different orders without having to return the storage container <NUM>', <NUM>''.

A further exemplary access station according to the invention is shown in <FIG>. The access station features three similar sets of two container handling modules 13a, 13b. Each set provides two separate access positions 23a,23b and corresponds to a dual version of the access stations disclosed in <FIG>. The provision of two adjacent access positions is made possible by the moveable shuttle <NUM>. When two container handling modules 13a,13b are arranged in parallel, i.e. the respective rail assemblies <NUM>,<NUM> are parallel and adjacent, the container holders 8a,8b of the two container handling modules 13a,13b are not able to rotate around their respective axis of rotation C when the respective shuttles <NUM> are in the same linear position. Thus, to retrieve and present a storage container <NUM> at the first access position 23a, the shuttle <NUM> of the first container handling module 13a is first moved to the second linear position L2, while the shuttle <NUM> of the second container handling module 13b is in the first linear position L1. The storage container is then loaded onto the first or second container holder 8a,8b being in the second angular position P2. The first and second container holders 8a,8b of the first container handling module 13a is then rotated around the axis of rotation C to move the first or second container holder, on which the storage container is loaded, to the first angular position P1. The shuttle <NUM> of the first container handling module 13a is finally moved to the first linear position L1 to present the storage container at the access position of the first container handling module 13a. When the first container handling module 13a is arranged to present the storage container, the second container handling module 13b may move to retrieve another storage container for subsequent presentation at its respective access position 23b.

The station framework 34a,34b of the access station is an extended version of the station framework described above. When the access station is incorporated into a storage system <NUM> as described above, the first and second container handling modules are arranged such that the respective container holders are separated by a distance substantially corresponding to the width of the rails making up the horizontal top rail grid <NUM>.

<FIG> shows a further exemplary access station according to the invention, wherein two adjacent access positions 23c,23d are obtained by arranging the rail assemblies <NUM>,<NUM> of a third container handling module 13c and a fourth container handling module in a perpendicular relationship.

Claim 1:
An access station in a storage system (<NUM>), the access station comprising at least one container handling module (<NUM>),
the container handling module (<NUM>) comprising:
a first container holder (8a) and a second container holder (8b),
wherein each of the first and second container holders (8a,8b) is arranged to accommodate a storage container (<NUM>) and is rotatable around an axis of rotation (C) between a first angular position (P1) and a second angular position (P2), the second angular position being opposite the first angular position relative to a centreline (C) of a rotary shaft (<NUM>),
wherein the container handling module (<NUM>) is arranged to present a storage container (<NUM>) at an access position (<NUM>) of the access station, at which access position an operator (<NUM>) or robot has access to the storage container (<NUM>) when the storage container is supported by either the first or the second container holder (8a,8b) being in the first angular position (P1) and the shuttle (<NUM>) is in the first linear position (L1), characterised in that the container handling module (<NUM>) further comprises a shuttle (<NUM>), and a rail assembly (<NUM>,<NUM>), wherein the first and second container holders (8a,8b) are rotatably mounted to the shuttle (<NUM>) via said rotary shaft (<NUM>), and wherein the shuttle (<NUM>) is configured for linear movement in a horizontal direction (H) between a first linear position (L1) and a second linear position (L2) relative to the rail assembly.