Patent Description:
Some commercial and industrial activities require systems that enable the storage and retrieval of a large number of different products. One known type of system for the storage and retrieval of items in multiple product lines involves arranging storage bins or containers in stacks on top of one another, the stacks being arranged in rows. The storage bins or containers are removed from the stacks and accessed from above by load handling devices, removing the need for aisles between the rows and thereby allowing a large number of bins or containers to be stored in a given space.

Methods of handling containers or bins stacked in rows are well known in the art. <CIT>) describes a storage and fulfilment system in which stacks of bins or containers are arranged within a frame structure. The bins or containers are accessed by load handling devices operative on tracks located on the top of the frame structure. The load handling devices lift bins or containers out from the stacks, multiple load handling devices co-operating to access bins or containers located in the lowest positions of the stack. One form of robotic load handling device is described in <CIT>) where each robotic load handler only covers one grid space of the frame work structure, thus allowing higher density of load handlers and thus higher throughput for a given sized system. <CIT>) discloses a storage system according to the preamble of claim <NUM>.

In some implementations of such container or bin handling systems, there can be a very large number of robotic load handling devices running on a single grid, the grid containing a large number of bins or containers in stacks. The robotic load handling devices may be running on the grid in close proximity to each other and often travelling at speed. Such storage systems are located within buildings that due to their size will often require the framework and grid structure to be built around structural members such as pillars supporting roof structures and other services.

Furthermore, in order to take full advantage of the space within the building, the framework and grid may be built so as to fill the available space, thereby requiring the grid to be located adjacent walls and other structures.

Moreover, for safety reasons in the event of malfunction, the edges of the grid and framework structure may require protection and the robotic load handling devices may need to be prevented from overshooting the edges of the grid.

According to the invention there is provided a storage system comprising: a first set of parallel tracks and a second set of parallel tracks extending transverse to the first set in a substantially horizontal plane to form a grid pattern comprising a plurality of grid spaces; a set of uprights, the uprights and tracks together defining a framework; a plurality of storage containers arranged in stacks beneath the grid spaces, located beneath the tracks and within the framework; at least one load handling device disposed on the grid, arranged to move laterally above the stacks on the tracks, the load handling device comprising a lifting device arranged to lift one or more containers, or parts thereof, from a stack; wherein the system comprises an additional separate portion of framework comprising uprights with tracks mounted thereon, the additional separate portion of framework being located adjacent the storage system and in contact with the storage system, the additional separate portion of framework being further provided with barrier means, the barrier means extending over the tracks of the additional separate portion such that any load handling device over running the tracks of the storage system will continue to travel on to the tracks of the additional separate portion of framework and impacts the barrier, the forces generated by said impact being directed into the barrier and the separate portion and not being transmitted in to said storage system.

According to the invention there is provided a method of protecting a storage system, the storage system comprising tracks on which load handling devices are operable: providing a separate framework structure comprising tracks; mounting barrier means on the separate framework structure; locating said separate structure adjacent the storage system such that the tracks of the separate structure abut the tracks of the storage system, the barrier means extending toward the main storage system in a direction substantially parallel to the tracks.

Preferred features of the invention are defined in the claims.

In this way, the present invention overcomes the problems of the prior art and provides a safety system ensuring that malfunctioning or over running robotic load handling devices are safely stopped without damage occurring to the main storage system.

As shown in <FIG> and <FIG>, stackable storage containers, known as bins <NUM>, are stacked on top of one another to form stacks <NUM>. The stacks <NUM> are arranged in a frame structure <NUM> in a warehousing or manufacturing environment. <FIG> is a schematic perspective view of the frame structure <NUM>, and <FIG> is a top-down view showing a single stack <NUM> of bins <NUM> arranged within the frame structure <NUM>. Each bin <NUM> typically holds a plurality of product or inventory items <NUM>, and the inventory items within a bin <NUM> may be identical, or may be of different product types depending on the application. Furthermore, the bins <NUM> may be physically subdivided to accommodate a plurality of different inventory items <NUM>.

In the description below, bins <NUM> will be used to denote containers intended for the storage of inventory items <NUM>, whilst delivery containers DT will be used to denote containers filled or intended to be filled to fulfil customer orders placed by customers. It will be appreciated that this terminology is used for ease of reference and explanation within this document. However, it should be noted that the bins <NUM> and the containers DT may be of the same shape and configuration. Furthermore, delivery containers DT may be stored in bins <NUM> within the storage system or any part thereof.

The frame structure <NUM> comprises a plurality of upright members <NUM> that support horizontal members <NUM>, <NUM>. A first set of parallel horizontal members <NUM> is arranged perpendicularly to a second set of parallel horizontal members <NUM> to form a plurality of horizontal grid structures supported by the upright members <NUM>. The members <NUM>, <NUM>, <NUM> are typically manufactured from metal. The bins <NUM> are stacked between the members <NUM>, <NUM>, <NUM> of the frame structure <NUM>, so that the frame structure <NUM> guards against horizontal movement of the stacks <NUM> of bins <NUM>, and guides vertical movement of the bins <NUM>.

The top level of the frame structure <NUM> includes rails <NUM> arranged in a grid pattern across the top of the stacks <NUM>. Referring additionally to <FIG> and <FIG>, the rails <NUM> support a plurality of robotic load handling devices <NUM>. A first set 22a of parallel rails <NUM> guide movement of the load handling devices <NUM> in a first direction (X) across the top of the frame structure <NUM>, and a second set 22b of parallel rails <NUM>, arranged perpendicular to the first set 22a, guide movement of the load handling devices <NUM> in a second direction (Y), perpendicular to the first direction. In this way, the rails <NUM> allow movement of the load handling devices <NUM> in two dimensions in the X-Y plane, so that a load handling device <NUM> can be moved into position above any of the stacks <NUM>.

Each load handling device <NUM> comprises a vehicle <NUM> which is arranged to travel in the X and Y directions on the rails <NUM> of the frame structure <NUM>, above the stacks <NUM>. A first set of wheels <NUM>, consisting of a pair of wheels <NUM> on the front of the vehicle <NUM> and a pair of wheels <NUM> on the back of the vehicle <NUM>, are arranged to engage with two adjacent rails of the first set 22a of rails <NUM>. Similarly, a second set of wheels <NUM>, consisting of a pair of wheels <NUM> on each side of the vehicle <NUM>, are arranged to engage with two adjacent rails of the second set 22b of rails <NUM>. Each set of wheels <NUM>, <NUM> can be lifted and lowered, so that either the first set of wheels <NUM> or the second set of wheels <NUM> is engaged with the respective set of rails 22a, 22b at any one time.

When the first set of wheels <NUM> is engaged with the first set of rails 22a and the second set of wheels <NUM> are lifted clear from the rails <NUM>, the wheels <NUM> can be driven, by way of a drive mechanism (not shown) housed in the vehicle <NUM>, to move the load handling device <NUM> in the X direction. To move the load handling device <NUM> in the Y direction, the first set of wheels <NUM> are lifted clear of the rails <NUM>, and the second set of wheels <NUM> are lowered into engagement with the second set of rails 22a. The drive mechanism can then be used to drive the second set of wheels <NUM> to achieve movement in the Y direction.

In this way, one or more robotic load handling devices <NUM> can move around the top surface of the stacks <NUM> on the frame structure <NUM>, as shown in <FIG> under the control of a centralised control utility (not shown). Each robotic load handling device <NUM> is provided with lifting means <NUM> for lifting one or more bins <NUM> from the stack <NUM> to access the required products.

The body of the vehicle <NUM> comprises a cavity <NUM>, the cavity <NUM> being of a size capable of holding a bin <NUM>. The lifting means <NUM> comprises winch means and a bin gripper assembly <NUM>. The lifting means lifts a bin <NUM> from the stack <NUM> to within the cavity <NUM> within the body of the vehicle <NUM>.

In this way, multiple products can be accessed from multiple locations in the grid and stacks at any one time.

The robotic load handling devices <NUM> remove bins <NUM> containing inventory items <NUM> (not shown) therein and transport the bins <NUM> to picking stations (not shown) where the required inventory items <NUM> are removed from the bins <NUM> and placed into bins <NUM> comprising delivery containers DT. It is important to note that a delivery container DT may fit within a bin <NUM>. The bins <NUM> may comprise inventory items <NUM> or may comprise delivery containers DT. Furthermore, the delivery containers DT may comprise at least one bag <NUM>, the inventory items <NUM> being picked directly in to a bag <NUM> at a pick station (not shown).

The empty bins <NUM> or the bins comprising delivery containers DT or the bins comprising delivery containers DT and bags <NUM> may all be stored within the stacks <NUM>. It will be appreciated that all the bins <NUM> have substantially the same external shape and configuration.

<FIG> shows a typical storage system as described above, the system having a plurality of load handling devices <NUM> active on the grid above the stacks <NUM>.

<FIG> and <FIG> show the bins <NUM> in stacks <NUM> within the storage system. It will be appreciated that there may be a large number of bins <NUM> in any given storage system and that many different items <NUM> may be stored in the bins <NUM> in the stacks <NUM>, each bin <NUM> may contain different categories of inventory items <NUM> within a single stack <NUM>. In one system described above and further in UK Patent Application Number <CIT> the storage system comprises a series of bins <NUM> that may further comprise delivery containers DT with customer orders contained therein or may further comprise bins <NUM> with inventory items <NUM> awaiting picking contained therein. These different bins <NUM> and combinations thereof may be contained in the storage system and be accessed by the robotic load handling devices <NUM> as described above.

<FIG> shows a schematic perspective view of a separate portion of framework <NUM> comprising uprights <NUM> and tracks <NUM> in accordance with one form of the invention, the separate portion of framework <NUM> also comprising barrier means <NUM>. The barrier means <NUM> extend toward the main storage system and are substantially parallel to the direction of the tracks <NUM> in the separate portion of framework <NUM>.

The structure of the separate portion of the framework <NUM> is attached to the floor of a building (or level within a building) containing the storage system. However, the separate portion of framework <NUM> is not fixedly attached to the main storage system. The barrier <NUM> comprises any material or structure that may act as a crumple zone in the event of an impact from a robotic load handling device that has overrun the tracks of the main storage system due to malfunction or error in the system.

For example, the barrier may comprise a metallic honeycomb type structure, or an inflatable barrier, a barrier formed from any suitable resilient material such as padding or foam or rubber. The barrier may further comprise mesh or wire or tensioned cables or structures or materials. It will be appreciated that any structure, material or device capable of absorbing the forces generated by a load handling device impacting the barrier <NUM> may be used and need not be limited to the examples given above.

<FIG> is a schematic perspective view of two of the separate portions of framework <NUM> of <FIG>, the first separate portion 114a being located adjacent a first edge of the storage system of <FIG> and extending in the X direction, the second separate portion 114b being located adjacent a second edge of the storage system of <FIG> and extending in the Y direction of the main storage system.

As can be seen in <FIG>, the tracks <NUM> of the separate portions of framework <NUM> do not comprise whole grid squares.

<FIG> is a further schematic perspective view of the storage system of <FIG> with the separate portions of framework extending along the X and Y axes of the storage system. As can be seen in <FIG>, the separate portions of framework <NUM> may be supported on a mezzanine structure <NUM>.

In use, the separate framework <NUM> is positioned adjacent an edge of the main storage system such that the tracks <NUM> of the separate portion abut the tracks <NUM> of the main storage system. Suitable resilient material may be located between the tracks <NUM> and the tracks <NUM>. The edge of the main storage system may be the part of the storage system adjacent the edge of the building in which the system is located. However, it will be appreciated that the separate portion of framework <NUM> may be positioned any part of the main storage system where the movement of the robotic load handling devices may over run the grid of the main storage system and potentially impact and damage other parts of the building such as structural support members, pillars, walls, partitions and the like.

Should a robotic load handling device malfunction and overrun the main storage system, it will impact the barrier structure <NUM>. As the robotic load handling devices may be travelling up to <NUM> metres per second and weigh in the region of <NUM>, it will be appreciated that such an impact will generate a substantial force on the barrier and the separate portion of framework <NUM>.

As the separate framework structure <NUM> is not fixedly attached to the main framework structure <NUM>, the barrier <NUM> attached to the separate structure <NUM> absorbs the energy of the impact and may deflect. However, it will be appreciated that the barrier may not absorb all of the energy of the impact and forces may be transmitted to the framework of the separate portion. However, as the separate portion <NUM> is not attached to the main framework <NUM>, no forces will be transmitted to the main storage system and any damage as a result will be limited to the separate portion of framework <NUM> which is easily replaceable.

It will further be appreciated that whilst many of the above embodiments are described with reference to a main storage system, this definition is used for clarity purposes within the description. It will be appreciated that there may be several portions of framework within the main storage system, but all may be attached together. The separate portion of framework <NUM> is distinguished in that it is not fixedly attached to any part of the storage system comprising containers or bins <NUM> located in stacks <NUM> beneath the tracks <NUM>.

Claim 1:
A storage system comprising:
a first set of parallel tracks (22a) and a second set of parallel tracks (22b) extending transverse to the first set in a substantially horizontal plane to form a grid pattern comprising a plurality of grid spaces;
a set of uprights (<NUM>), the uprights (<NUM>) and tracks (<NUM>) together defining a framework (<NUM>);
a plurality of storage containers (<NUM>) arranged in stacks (<NUM>) beneath the grid spaces, located beneath the tracks (<NUM>) and within the framework (<NUM>);
at least one load handling device (<NUM>) disposed on the grid, arranged to move laterally above the stacks (<NUM>) on the tracks (<NUM>), the load handling device (<NUM>) comprising a lifting device (<NUM>) arranged to lift one or more containers (<NUM>), or parts thereof, from a stack (<NUM>);
characterized in that, the system comprises an additional separate portion of framework (<NUM>) comprising uprights (<NUM>) with tracks (<NUM>) mounted thereon, the additional separate portion of framework (<NUM>) being located adjacent and in contact with the storage system, the additional separate portion of framework (<NUM>) being further provided with barrier means (<NUM>), the barrier means extending over the tracks (<NUM>) of the additional separate portion such that any load handling device (<NUM>) over running the tracks (<NUM>) of the storage system will continue to travel on the tracks (<NUM>) of the additional separate portion of framework (<NUM>) and impacts the barrier (<NUM>), the forces generated by said impact being directed into the barrier (<NUM>) and the separate portion and not being transmitted in to said storage system.