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 containers or containers in stacks on top of one another, the stacks being arranged in rows. The storage containers or containers are accessed from above, removing the need for aisles between the rows and allowing more containers to be stored in a given space.

Methods of handling containers stacked in rows have been well known for decades. In some such systems, for example as described in <CIT>comprise freestanding stacks of containers arranged in rows in order to reduce the storage volume associated with storing such containers but yet still providing access to a specific container if required. Access to a given container is made possible by providing relatively complicated hoisting mechanisms which can be used to stack and remove given containers from stacks. The cost of such systems are, however, impractical in many situations and they have mainly been commercialised for the storage and handling of large shipping containers.

The concept of using freestanding stacks of containers and providing a mechanism to retrieve and store specific containers has been developed further, for example as described in <CIT>. '<NUM> discloses a mechanism for removing a plurality of stacked containers, using a robotic load handler in the form of a rectangular tube which is lowered around the stack of containers, and which is configured to be able to grip a container at any level in the stack. In this way, several containers can be lifted at once from a stack. The movable tube can be used to move several containers from the top of one stack to the top of another stack, or to move containers from a stack to an external location and vice versa. Such systems can be particularly useful where all of the containers in a single stack contain the same product (known as a single-product stack). In the system described in '<NUM>, the height of the tube has to be as least as high as the height of the largest stack of containers, so that that the highest stack of containers can be extracted in a single operation. Accordingly, when used in an enclosed space such as a warehouse, the maximum height of the stacks is restricted by the need to accommodate the tube of the load handler.

<CIT>) describes a system in which stacks of containers are arranged within a frame structure. A system of this type is illustrated schematically in <FIG> of the accompanying drawings. Robotic load handling devices can be controllably moved around the stack on a system of tracks on the upper most surface of the stack.

Other forms of robotic load handling device are further described in, for example, <CIT>.

<FIG> and <FIG> are schematic perspective views of a load handling device from the rear and front, respectively, and <FIG> is a schematic front perspective view of a load handling device lifting a bin.

A further development of load handling device is described in <CIT>) where each robotic load handler only covers one grid space, thus allowing higher density of load handlers and thus higher throughput of a given size system.

<CIT>) teaches a container array storage and retrieval system, in which containers are accessible from above by one or more overhead load handlers, by one or more lifters. The handlers and lifters engage with one or more clamps to hold and displace one or more containers, in particular, lifting multiple containers, when engaged with a bottommost container in a stack.

In such known storage systems a large number of containers are stacked densely. The contents of the containers may contain ignitable or inflammable products, items or goods such as matches, aerosols or solvents and the increased packing density of the containers may pose a fire risk.

According to the invention there is provided a storage system comprising: a first set of parallel rails or tracks and a second set of parallel rails or tracks extending transversely to the first set in a substantially horizontal plane to form a grid pattern comprising a plurality of grid spaces; a plurality of storage containers arranged in stacks, located beneath the rails and; at least one load handling device disposed on the grid, arranged to move laterally above the stacks on the rails, the load handling device comprising a lifting device arranged to lift one or more containers from a stack; wherein a number of the containers <NUM> comprise liner means the liner means acting so as to protect the storage system from items <NUM> contained within the container that may pose a safety risk; wherein the system is partitioned into smaller sub sections by partitioning means such that sections of the storage system are isolated from other sections of the storage system; and wherein the liner means comprise flame retardant or flame suppressant material, wherein the storage system forms part, in use, of a fulfilment system of an online retail organisation.

In this way, ignitable or inflammable goods may be more safely stored in containers in more densely packed storage systems.

In this way, the present invention overcomes the problems of the prior art and provides a system of increasing the reliability and reducing the overall cost of large bin handling storage systems.

The invention will now be described with reference to the accompanying diagrammatic drawings in which:.

As shown in <FIG> and <FIG>, stackable bins, known as containers <NUM>, are stacked on top of one another to form stacks <NUM>. The stacks <NUM> are arranged in a grid 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 containers <NUM> arranged within the frame structure <NUM>. Each bin <NUM> typically holds a plurality of product items (not shown), and the product items within a bin <NUM> may be identical, or may be of different product types depending on the application.

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 containers <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 containers <NUM>, and guides vertical movement of the containers <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>. It will be appreciated that the first 22a and second 22b set of tracks comprise double tracks that allow robotic load handling devices <NUM> to pass each other whilst over adjacent grid squares.

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> under the control of a central picking system (not shown). Each robotic load handling device <NUM> is provided with means for lifting out one or more containers or containers from the stack to access the required products. In this way, multiple products can be accessed from multiple locations in the grid and stacks at any one time.

<FIG> shows stacks <NUM> of containers <NUM> located within the framework structure <NUM>, the containers <NUM> being held in stacks <NUM> by co-operating surfaces of the containers <NUM> forming interference fits between adjacent containers <NUM> in the stack <NUM>. Furthermore, <FIG> shows a typical storage system as described above, the system having a plurality of load handling devices <NUM> active on the tracks <NUM> above the stacks <NUM> of containers <NUM>.

It will be appreciated that there may be a large number of containers in any given storage system and that many different goods may be stored in the stacks, each container may contain different goods within a single stack. Such dense packing of products and items in containers may pose a fire risk particularly if some of the items are inflammable or ignitable such as matches, nail varnish remover, other solvents, charcoal, aerosols or other materials or fluids in pressurised cans. It will be appreciated that these are merely examples of ignitable or inflammable products that may need to be stored safely in the storage system and that the invention envisages any type of inflammable, ignitable or flammable product may be stored as described below.

<FIG> shows a liner <NUM> for a container <NUM>.

The liner <NUM> is formed from a suitable material such as metal or a flame retardant plastics material. A metal liner <NUM> may be formed from aluminium or aluminium alloys or from mild steel or any other suitable metal. A flame retardant plastics liner <NUM> may be formed from PVC or a glass loaded polymer with suitable flame retardant properties. It will be appreciated that these are examples only and that the liner <NUM> may be formed from any suitable flame retardant material.

The liner <NUM> is formed so as to conform to the inner surface of the container <NUM>. The liner <NUM> is formed so as to be removable from the container <NUM> either manually or robotically. The liner <NUM> is shaped such that the ability of the containers <NUM> to be stacked is not inhibited.

In this way, containers <NUM> comprising liners <NUM> may be stored in the storage system described above with reference to <FIG>. Accordingly when inflammable items <NUM> are required to be stored in the storage system, a container <NUM> having a liner <NUM> may be used.

Preferably, any container <NUM> comprising a liner <NUM> and an inflammable product or products <NUM> is stored in a position within a stack <NUM> such that there is a further container <NUM> above the lined container <NUM>, the base of the container <NUM> immediately above the lined container forming a lid over the inflammable items <NUM> held within the liner <NUM> in the container <NUM>.

When inflammable items <NUM> for storage in the system are received at the input of the storage system (not shown), the items <NUM> are loaded in to a container <NUM> comprising a liner <NUM>. This loading may occur manually or robotically. Alternatively, a load handling device <NUM> may act to collect a container <NUM> comprising a liner <NUM> from the one of the stacks <NUM> of the storage system. Such a stored, lined container, which may already contain inflammable items <NUM> of the same or different type as those to be stored in the system, or which may be empty, is transported to an appropriate goods inward of the storage system and the products <NUM> placed in the lined container.

After the items <NUM> are placed in the liner <NUM> in the container <NUM>, a load handling device <NUM> transports the loaded container <NUM> to an appropriate position and places the container <NUM> in a stack <NUM> within the storage system.

When a customer order requires an inflammable product <NUM>, the container <NUM> comprising the liner <NUM> is removed from the relevant stack <NUM> and transported to a pick station (not shown) where the requisite item or items <NUM> are removed from the container and added to the customer order. The customer order may include one or more inflammable items and may include further items such as fresh produce or other non-food items. The customer order is preferably packed in to a delivery container in preparation for onward transmission to a delivery vehicle for delivery to the customer. The order packing may be manual or automatic and may occur on the grid or at a pick station (not shown). The delivery container may comprise a container comprising bags, boxes or further liners or any other suitable delivery packaging. The delivery container may be temporarily returned to the storage system to await onward transmission to a delivery vehicle.

In another method of picking inflammable items <NUM> from the storage system, a load handling device <NUM> may collect a container <NUM> comprising inflammable items and transport it to a first pick station for a first item <NUM> to be removed and added to a customer order. A load handling device <NUM> may then transport the same container <NUM> to a further pick station (not shown) to fulfil a further customer order and this may continue until such a time that the container <NUM> comprising the liner <NUM> no longer comprises any inflammable items <NUM> or until no further customer orders require inflammable or ignitable items <NUM> from the given container <NUM>.

It will be appreciated that if the container <NUM> no longer contains inflammable or ignitable item then it may be returned to the goods inward portion of the storage system for refilling or it may be returned in to a stack <NUM> until it is required. Furthermore, it will be appreciated that the liner <NUM> may be removed at an appropriate position on the grid and the container <NUM> used to store products and items not requiring a liner <NUM>.

It will be appreciated that in any given storage system there may be a number of containers <NUM> comprising liners <NUM> that are used to store ignitable or inflammable products <NUM>. Furthermore, multiples of the same product <NUM> may be stored in a given lined container <NUM>. Alternatively, a plurality of different products <NUM> may be stored in a given lined container <NUM>. In a further form of the invention, a container <NUM> may comprise two or more liners <NUM> acting so as to sub-divide the container in to two or more separate portions thereby enabling different products <NUM> to be separated within a single container <NUM>.

It will further be appreciated that multiple containers <NUM> comprising liners <NUM> may be stacked in a given stack <NUM>, a single stack <NUM> may comprise only containers <NUM> comprising liners <NUM>, a plurality of stacks <NUM> may comprise only one lined container and some stacks <NUM> may not comprise any lined containers.

Furthermore, the liner means <NUM> described above are removable from the containers <NUM>. However, it will be appreciated that the liner means may be fixedly attached to the interior surface of the container <NUM> or the liner means <NUM> may comprise a coating on the internal surface of the container <NUM>.

Moreover, the embodiments described above and detailed in the accompanying figures assume that the storage system comprises containers <NUM> in stacks <NUM> disposed within a framework <NUM> in an unfettered manner. According to the invention, the system is partitioned by suitable partitioning means into smaller sub sections for example for safety reasons.

The partitioning enables sections of the storage system to be isolated from other sections. This may be necessary if there is a fire, for example, and fire suppressant means are used in a given area to extinguish the fire. Furthermore, in the case where the system is used for alternative uses, there may be advantages in having different gaseous atmospheres in different portions of the system. This may be achieved by partitioning the system. It will be appreciated that the partitioning means may be temporary and remotely deployable, for example roller shutters disposed under the grid.

The partitioning of the storage system enables containers <NUM> comprising inflammable or ignitable items to be stored separately from containers <NUM> comprising other items, products or goods.

Claim 1:
A storage system comprising:
a first set 22a of parallel rails <NUM> or tracks and a second set 22b of parallel rails <NUM> or tracks extending transversely to the first set 22a in a substantially horizontal plane to form a grid pattern comprising a plurality of grid spaces;
a plurality of storage containers <NUM> arranged in stacks <NUM>, located beneath the rails <NUM> and;
at least one load handling device <NUM> disposed on the grid, arranged to move laterally above the stacks <NUM> on the rails <NUM>, the load handling device <NUM> comprising a lifting device arranged to lift one or more containers <NUM> from a stack <NUM>;
characterised in that
a number of the containers (<NUM>) comprise liner means (<NUM>), the liner means (<NUM>) acting so as to protect the storage system from items (<NUM>) contained within the container (<NUM>) that may pose a safety risk;
wherein the system is partitioned into smaller sub sections by partitioning means such that sections of the storage system are isolated from other sections of the storage system; and
wherein the liner means (<NUM>) comprise flame retardant or flame suppressant material, wherein the storage system forms part,
in use, of a fulfilment system of an online retail organisation.