GB2480322A

GB2480322A - Storage apparatus & inventory item verification process

Info

Publication number: GB2480322A
Application number: GB1008077A
Authority: GB
Inventors: John George Bend
Original assignee: TOOL CONTROL SYSTEMS Ltd
Current assignee: TOOL CONTROL SYSTEMS Ltd
Priority date: 2010-05-14
Filing date: 2010-05-14
Publication date: 2011-11-16
Anticipated expiration: 2030-05-14
Also published as: GB2480322B; GB201008077D0

Abstract

An item storage apparatus includes a plurality of separate storage sections 8a-d and 10, each storage section having an access member (6, Fig 2) and a locking device (14, Fig 3) arranged to selectively lock the access member (6) to control access to the storage section 8a-d and 10. The apparatus also includes a user identification device 54 for identifying authorised users and a processing device (36, Fig 4) for controlling operation of the locking devices (14) independently of each other. The locking devices (14) include a motor (Fig 4) and a locking member (22, Fig 2), said motor (16) moving a locking member (22, Fig 2) between a locked position and an unlocked position to allow access to the access member (6) in response to commands from the processing device (36) when an authorised user has logged into the system, and the authorised user is authorised to access one or more of the storage sections (6,10). The apparatus may be used to manually verify items stored within the apparatus. A method for verifying the presence and/or absence of inventory items within a storage apparatus is also disclosed.

Description

INVENTORY STORAGE APPARATUS & INVENTORY ITEM

VERIFICATION PROCESS

The present invention relates to inventory storage apparatus and in particular, but not exclusively, to inventory storage apparatus for storing hand tools. The invention also relates to an inventory item checking process.

Traditionally engineers have owned and maintained their own collections of tools which are stored in mechanically locking metal containers on the shop floor. This raises a number of problems for employers. Firstly, work areas can become cluttered with a number of metal tool containers which consumes valuable workspace and poses a health and safety risk. The employer cannot be certain that each engineer possesses tools of the appropriate type and specification for any particular task, and since the tools belong to the engineer it is difficult or expensive to impose quality controls such as tool inspections and calibration regimes any of which may contravene regulations and working practices imposed by aerospace authorities.

Frequent operation of mechanical locks on the tool containers can be time consuming and so there is the tendency to leave tool stores open during a shift and it is difficult to move engineers from one workplace to another as this requires their metal tool containers to be moved as well giving rise to a degree of disruption to the workplace.

Furthermore, it is difficult to identify when tools are lost, which poses a significant danger in the aerospace industry where foreign object damage can have catastrophic consequences.

With this in mind many engineering companies are seeking to replace employee owned tools and containers with company owned tools and containers. However this poses new challenges for companies, since it is necessary to ensure that tools are kept secure from theft, are only accessible to authorised users and are returned to the appropriate storage containers after use. Therefore there is a need for storage units that can provide secure storage for tools, and other inventory items, and a means of checking that the inventory items have been returned to the storage unit, for example at the end of a working shift, during the shift or prior to a new shift commencing. This can help to identify lost, stolen or damaged tools and equipment. This is particularly important when tools are used for repairing or maintaining aircraft engines, as any tools left inside the engine after completion of the job could cause severe damage.

Similarly, in the case of surgical tools, it is essential to ensure that no tools are left inside a patient after an operation.

An inventory control system is described in GB2406092, which includes a lockable storage container having a plurality of storage locations each having a magnetic or optical sensor to detect the presence or absence of tools in the storage locations. Each storage location comprises a recess formed in a tool tray. Each recess matches the shape of the tool stored therein. The system disclosed is complicated and expensive to manufacture and implement since there is the need to create and maintain an inventory database and deploy electronic sensors and wiring within the formed tool trays. The system described does not accurately record the date and time of events since time keeping is reliant on an external computer which is subject to time differences introduced through a communications lag, for example when using the inventory control system away from the communications link or when the external computer is not running. Furthermore, the access system is not very secure. All users have access to all drawers and compartments since the access control system automatically unlocks all of the container drawers when an authorised user logs in.

The system may easily be defeated by placing metal scraps or similar over the sensors.

WO 2004/014189 teaches a system that is used to retro-fit a drawer in an existing container. The system includes a framework that is insertable into the drawer, to define a number of individually lockable compartments within the drawer. The system uses solenoid type locking mechanisms to control access to the compartments, together with a computer interface to restrict access to authorised users. However, the system is only applicable to sub-compartments within existing drawers. It is not possible to control access to each of the drawers individually since they share a conimon locking mechanism and the system does not include any contents verification process. This significantly limits the utility of the system disclosed in WO 2004/014189.

For systems having multiple locking devices, the electrical current required to operate the devices can be very large, particularly when a user opens more than one compartment simultaneously. Thus this type of system often requires a large power supply to operate a number of electronic locking devices, which is expensive, inefficient and makes it difficult to create mobile systems.

Accordingly, the invention seeks to mitigate at least one of the above-mentioned problems, or to at least provide an alternative to known apparatus.

According to one aspect of the invention there is provided inventory item storage apparatus, including a plurality of separate storage sections, each storage section having an access member and a locking device arranged to selectively lock the access member to control access to the storage section; a user identification device for identifying authorised users; and a processing device for controlling operation of the locking devices independently of each other, wherein each locking device includes a motor and a locking member, said motor being arranged to move the locking member between a first operational position wherein the access member is unlocked and a second operational position wherein the access member is locked, wherein the processing device, in response an authorised user logging into the system, is arranged to open the storage sections that the authorised user is authorised to access by operating the locking devices associated with those storage sections.

Advantageously the apparatus can include a message bus, and each locking device can include a local processor for controlling operation of its motor, and wherein the processing device is arranged to communicate with each of the local processors via the message bus. Thus the processing device is arranged to send messages to, and receive messages from, each of the local processors via the message bus. This enables the processing device to operate each locking device independently of the others in a very robust fashion since the arrangement is highly tolerant to electrical noise, which is useful in environments where machinery and welding gear is operated such as in factories and workshops.

The independent operation of the locking devices enables the processing device to operate the locking devices sequentially, and the processing device can be programmed appropriately. This limits the peak current drawn from a power supply unit. Any suitable sequence can be used, for example operating each locking device one at a time, operating a small number of locking devices substantially simultaneously, etc. The most effective way of limiting the peak power requirement is to operate each locking device individually. The inventor has discovered that it is possible to do this for inventory item storage units, such as tool cabinets, in a time period that is acceptable to users, typically less than one second. In a preferred embodiment, each local processor monitors the current drawn by its motor against time (typically in milliseconds). This data is compared against configurable reference data for the locking device. If the monitored current and / or time exceeds the associated reference data, perhaps by mechanical fault or by abuse by a user, then the operation is terminated and the fault reported to the processing device via the message bus. Preferably the fault data is recorded, for example in memory means.

Advantageously the apparatus can include a container arranged to house the plurality of storage sections. The storage sections can be fixed, such as a cupboard, or moveable such as a drawer. Typically each access member comprises one of the following: a drawer, a door, a removable tray or box. For example, the container can include at least one drawer, and preferably a plurality of drawers. The container can include at least one cupboard that is accessed by a door, and preferably a plurality of cupboards each having a door. It will be apparent to the skilled person that while the invention is particularly suited to the storage of hand tools, it can be used to store any type of inventory item, for example component parts, devices, instruments, etc. Advantageously at least some of the locking devices include a mechanism for converting a rotary output from the motor to linear movement of the locking member.

The locking member is arranged to move linearly between a retracted, unlocked, position and an extended, locked, position. For example, the mechanism can include at least one gear and a rack, in a rack and pinion arrangement.

At least some of the access members include a locking formation and the locking member is arranged to selectively engage the locking formation. Advantageously the locking formation can include a latching mechanism for engaging the locking member. The latching mechanism is arranged to prevent damage to the locking member in the event that the user closes the access member when the locking member is in the locked position. The latching mechanism includes a moveable latch that is biased to a locking position by resilient means. The latch is movable between locked and unlocked positions. The latch is arranged to engage the locking member when the locking member is in the lock position and the access member is moved in the opening direction thereby preventing the access member from opening. The latch is arranged to allow the access member to move to a fully closed position when the locking member is in the locking position by moving to a non-locking position.

Preferably the latch is pivotally mounted on support arm attached to the access member. The latch pivots out of engagement with the locking member when the access member is fully closed.

Advantageously the apparatus can include means for determining the operational status of each locking member. In a preferred embodiment the means is determined by the local processor according to the operational condition of the motor and/or components that transfer drive from the motor to the locking member. The local processing device is arranged to monitor the operational status of the locking device so that the actual operational status is compared with the control signals received from the processing device. The processing device is arranged to send and receive messages to each of the locking devices periodically. Thus from the control signals received from the processing device, the local processor knows the operational condition the locking device should be in and can determine from the actual operational condition of the locking member if it needs to operate the motor to bring the actual status into line with the status required by the processing device. This is particularly useful in the event that an unscrupulous person tries to override the locking device by forcing the locking member out of engagement with the locking formation since the local processer is arranged to activate the motor to move the locking member back to the locking position since the required status and the actual status will be different. Thus the locking arrangement is very secure.

The means for determining the operational status of the locking member can include an encoder for monitoring the rotational position of the motor. Alternatively, the motor can comprise a stepping motor to accurately control the rotational orientation of the motor.

Advantageously the apparatus can include sensors for detecting if each access member is in an open and/or closed position. For example, each access member can have a limit switch associated therewith that is arranged to determine the open/closed status of its associated access member. The processing device and/or the local processor can be arranged to operate the locking device according to the signals received from the sensors. The sensor signals can be used to determine if the locking member should be operated, for example, by restricting issuance of lock signals to those locking devices wherein the sensor signal confirms that the access member is in the closed position. This reduces the possibility of the locking member being in the locking position when the access member is closed. Advantageously each local processor can emit a message to the processing device via the message bus informing it of a change of open and/or closed state of the access member.

Each locking device can include a local indicator to visually display the locking status of the locking member.

The apparatus can include memory means, and the processing device is arranged to store event related data in the memory means. Advantageously the memory means includes non-volatile memory so that data is not lost in the event of a power failure.

The processing device is arranged to automatically unlock at least one of the locking devices when an authorised user is identified from data received from the identification device. Each authorised user is granted access to at least one of the storage sections. In response to identifying an authorised user; the processing device is preferably arranged to operate the locking devices associated with those storage sections sequentially. The processing device can determine which of the storage sections the user is authorised to access from data stored on a user identification device, such as a smart card or token. Additionally, or alternatively, the processing device can be arranged to look up access data from a database. The database can be stored locally, for example in the memory means and / or can be stored remotely and the processing device is arranged to access the database via a data link.

The identification device can include at least one of the following: a card reader; a proximity detector; and / or a keypad pin system. The card reader can be a smart card reader and/or a swipe card reader. The proximity detector can be of the type that is arranged to detect a token and that is arranged to obtain from the token data stored therein wirelessly.

The processing device can be arranged to enter a master lock mode when presented with a master lock mode identity device. In the master lock mode the processing device is arranged to prevent all standard users from accessing the cabinet. The cabinet remains in the master lock mode until a user having a master lock mode identity device logs in and changes the status to a normal operational mode. The cabinet can be arranged such that the change of status from master lock mode to normal mode can be done manually by the user and / or automatically by the processing device and/or by a supervising computer. Advantageously the state for the lock mode is retained in non-volatile memory to prevent users by passing the lock mode by powering off and on the system.

The processing device can be arranged to record the identity of the user whether access is granted or not. Preferably the data is recorded in the memory means.

The apparatus includes a real-time clock wherein the processing device is arranged to record at least one of the following: the time at which a user logs in, the time at which a user logs out, the time of opening of an access member, the time of closing an access member. The real-time clock comprises a non-volatile calendar-clock and the recorded time is to be understood as meaning recording the clock time and / or date.

Preferably the data is recorded in the memory means.

Advantageously the processing device can be arranged to initiate a verification process wherein the user is required to open each of the storage sections to which he has access and to check the presence and/or absence of each of the inventory items stored in the storage sections. This provides a much simpler and cheaper verification means than the use of a complex sensor system and users are given a greater sense of their responsibility since each user is required to confirm the verification by a conspicuous, recorded action.

Advantageously the processing device is arranged to initiate a timer at the start of the verification process that provides the user with a predetermined period of time to perform the verification process, and wherein if the verification process is not completed within the time period the processing device is arranged to operate the locking devices to lock the storage sections. The user can indicate to the processing device that the verification process has been completed by making an input via a manual control such as a dedicated button or keypad.

Advantageously the processing device is arranged to monitor output signals from sensors arranged to detect the opening and/or closing of the access members. This enables the processing device to ensure that the user has checked each of the storage sections to which he has access. Advantageously the processing device can record which storage sections were accessed and optionally the period of time that the storage sections were accessed for. This prevents users from trying to cheat the system by quickly opening and closing the drawers and doors without checking that the inventory items are present.

The processing device can be arranged to control access to each of the storage sections accessible to the user during the verification process by controlling operation of the locking devices. Thus the processing device can control the sequence in which each of the storage sections are reviewable. It also enables the processing device to allow access to one storage section at a time to ensure that sufficient time is given by the user to each of the storage sections.

The apparatus can include a data link for connecting a computer device to the processing device. For example, the network data link can include at least one of the following: Ethernet, RS232 and ZigBee connections. This enables a user to connect, for example a laptop computer, to the apparatus to obtain, and optionally view, data currently stored in the memory means. Additionally, or alternatively, data links from a plurality of cabinets can be connected to a central supervising computer. Thus all records can be easily accessed and retrieved and the supervising computer can control any of the cabinets connected to it.

According to another aspect of the invention there is provided an inventory item verification process for inventory item storage apparatus comprising a plurality of storage sections each having an access member and a locking device arranged to selectively lock the access member; and a processing device arranged to control operation of the locking devices, said method including the processing device automatically initiating the verification process according to a predetermined schedule and indicating the start of the process to a user via an output device, and the user opening each of the storage sections to which he has access to check the presence and/or absence of inventory items that are stored in the storage sections.

The visual inspection indicates the presence and/or absence of the tools in the storage sections. Thus the user is able to compare the tools that are actually present against the tools that should be present and quickly assess their condition. This makes it easy to assess whether all the tools taken from the container have been returned after use, thus reducing the risk of any tools being inadvertently left behind. Safety in critical situations such as aircraft engine maintenance is thus significantly improved. The invention also reduces the risk of tools being lost or stolen, since the fact that a tool has gone missing can be indicated immediately. The system also makes it possible to monitor which tools are being taken for any specified task, thereby helping to ensure best practice in maintenance operations.

At least some of the storage sections can include individual storage locations for at least some of the inventory items. Each individual storage location can include an arrangement of pegs or mounting members on which the associated inventory item can be located. Optionally, an outline of the inventory item can be provided on a storage section insert such as a tool tray or liner, for example by printing, and br each inventory item storage location can be labelled with an inventory item identifier.

Additionally, or alternatively, some of the storage sections can include tool trays having recesses formed therein that are arranged to match the shape of the inventory item. The individual storage locations assist the visual inspection process since it is very easy for a user to quickly identify which of the inventory items is present and which is absent.

The method can include the processing device initiating a timer at the start of the verification process to provide the user with a period of time to perform the verification process. The method can include the processing device operating the locking devices to lock the storage sections if the verification process is not completed within the time period. The user can indicate to the processing device that the verification process has been completed by making an input via a manual control such as a dedicated button or other input means The method can include the processing device monitoring output signals from the sensors that are arranged to detect the open and/or closed status of the access members associated with the storage sections. This enables the processing device to determine which of the storage sections the user has verified.

The method can include recording the storage sections that accessed by the user. The processing device can be arranged to record which storage sections are accessed by the user in memory means. By comparing the storage sections that were accessed against the storage sections that the user is authorised to access, the processing device can determine whether or not all of the allowable storage sections were accessed during the process.

The method can include recording the period of time that each of the storage sections is accessed for, for example by recording the time that the access member was opened and the time that the access member was closed, from signals received from the sensors and the clock. This prevents people from tiying to cheat the system by quickly opening and closing the drawers and doors without checking that the inventory items are present. The processing device can be arranged to record the period of time that each of the storage sections is accessed for in the memory means.

The method can include the processing device controlling the sequence in which each of the storage sections is accessible to the user by controlling operation of the locking devices. Thus the processing device can control the sequence in which each of the storage sections are reviewed, for example be only allowing one storage section to be checked at a time.

The method can include controlling access to the storage sections such that only a single storage section can be verified at a time.

The method can include providing a user identification device, and recording the identity of the user.

The method can include determining which of the storage sections the user is authorised to access and controlling the locking devices to limit access to those storage sections. This can be achieved, for example, by the user identification device or the processing device.

According to another aspect of the invention there is provided inventory item storage apparatus, including a plurality of separate storage sections, each storage section having an access member and a locking device arranged to control access to the storage section; a message bus; and a processing device for controlling operation of the locking devices independently of each other; wherein at least some of the locking devices include a motor, a local processor and a locking member, said motor being arranged to move the locking member between a first operational position wherein the access member is unlocked and a second operational position wherein the access member is locked, and the processing device is alTanged to send control signals to each local processor via the message bus, and each local processor is arranged to control operation of its associated motor according to the signals received from the processing device, thereby selectively locking and unlocking the access member. The processing device is arranged to receive signals from each of the local processing devices.

An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is an isometric view of a tool cabinet having a plurality of drawers and a compartment accessible via a door; Figure 2 is an isometric view of one of the drawers shown in Figure 1 together with a locking mechanism; Figures 3a and 3b show views of the drawer of Figure 2 from above when in a closed position and when in an open position respectively; Figure 4 is a schematic for the cabinet control system; and Figures 5a to 5f are flow diagrams illustrating the steps involved in a user operating the cabinet and a tool verification procedure.

The cabinet 2 shown in Figures 1-4 is for storing inventory items such as tools, parts, etc, and includes a steel cabinet housing 4, which may be static or mobile (for example, it may be mounted on castors 6). The cabinet includes four inventory item drawers 8a-8d and a compartment 10 accessible via a door 12. Each drawer 8 can optionally include a liner, for example of a rigid foam material, having a number of cut-out recesses, which are shaped to receive specific inventory items. The recesses are preferably colour-coded, to provide a simple visual indication that an inventory item has been removed. For example, the recesses may have a bright colour (e.g. yellow), while the top surface of the drawer liner has a contrasting colour (e.g. black).

Alternatively, each drawer 8, and the compartment 10, may include a number of inventory item pegs which designate individual inventory item storage areas on which the inventory items can be mounted.

Each drawer 8 and door 12 has an individually operable lock 14 (three of those devices are shown in Figure 4: 14a-n). Each lock 14 includes a motor 16 controlled by a local Programmable Logic Controller (PLC) 18, a mechanism for converting rotational movement into linear movement 20, a locking element 22, a limit switch 24, and a status indicator 26.

The mechanism for converting rotational movement into linear movement 20 can be of any conventional type, for example may include a gearing arrangement together with a rack (rack and pinion arrangement). Optionally, the mechanism 30 can include a latching arrangement 34 to maintain the position of the locking element 22.

The following description refers to the arrangement and operation of the s 14 with reference to the drawers 8. However it is to be understood that the description also applicable to the locking arrangement of the door 12. Thus references to monitoring opening and closing of drawers 8 is to be understood as being applicable to the opening and closing of the door 12.

The mechanism 20 is driven by the motor 16, which in turn drives movement of the locking element 22. The locking element 22 is arranged to move along a substantially linear path into and out of a casing 28. When the locking element 22 is retracted into the casing 28 the drawer 6 is in an unlocked condition. When the locking element 22 protrudes from the casing 28 into a locking position, it is arranged to engage with a fixture 30 on the drawer 8 such that the locking element 22 restrains movement of the drawer 8 and therefore locks its position.

The fixture includes an arm 32 having a spring-loaded latching member 34 located towards one end. In this arrangement, the latching member is arranged such that in the event of the locking element 22 being in the locking position when the drawer is closed, the latching member 34 pivots when it engages the locking element 22 to enable the arm 32 to move over the locking element into the locking position and the lock spring element biases the latching member 34 to the locking position. Thus this arrangement provides a safety feature to prevent damage to the locking element 22 in the event that the drawer is closed when the locking element 22 is in the locking position.

Alternatively, the fixture 30 can comprise a substantially L-shaped bracket having a slot formed into its body for receipt of the locking element 22.

Each lock 14 is connected to a central processing unit (CPU) 36 via a digital message bus 38. The bus 38 is preferably a RS485 message bus and each lock 14 has an address on the message bus. The CPU 36 is arranged to send and receive messages to and from each lock 14 via the bus 38. The CPU 36 communicates with the local PLC 18, the arrangement is such that the motor is a slave device that is controlled by the CPU 38 via the PLC 18. Thus the CPU is programmed to send open/close messages to the lock periodically, typically from tens to hundreds of times per second. The PLC 18 operates the motor 16 in accordance with the instructions received from the CPU 36. The local PLC 18 also sends signals back to the CPU 36 that inform the CPU of the actual status of the motor 16, i.e. whether it is in the locked/unlocked position. The local PLC 18 is connected to the limit switch 24, which is arranged to provide signals that indicate the open / closed status of the drawer 8. From the change in output of the limit switch 24, the local PLC 18 informs the CPU 36 of the open / closed status of the drawer 8 thus the CPU 36 can determine whether to send an open or a closed signal to the lock 14 according to the operational status of the drawer 8. This prevents the locking mechanism 14 from moving the locking element 22 into the locked position when the drawer 8 is in the open position. In the event that the drawer 8 is closed when the locking element 22 is in the closed position, the arrangement of the locking fixture 30 having a latch 34, prevents damage to the locking element 22.

The indicator 26 displays the locking status of the lock 14.

A significant advantage of the control arrangement is that the CPU 36 can control operation of the locks 14 such that they open in a sequential fashion. For example each lock can be operated at a different time, or groups of small numbers of locks can be opened substantially simultaneously, depending on the number of locks contained within the cabinet and the power supplies 40 available to each lock group. This significantly limits the maximum current required by the locking system from a power supply unit 40. For cabinets 2 having two to ten drawers 8, the locks 14 can be opened sequentially, one after the other, within an acceptable time frame for users. Since the locks 14 require less peak electrical current when operated in this fashion, the power supply unit 40 and cabling can have a much lower rating. Also, the cabinet 2 operates very efficiently. Furthermore, using an RS485 based message bus provides an arrangement which is highly tolerant to electrical noise, an arrangement which is beneficial for inventory item cabinets that are going to be used in workshop type environments where other machinery will be operated.

A further advantage of the control arrangement is that in the event of an unscrupulous person trying to open a drawer 8 by using a rod inserted into the cabinet 2 to force the locking element 22 back' into its casing 28, the local PLC 18 will fire up the lock motor 16 in order to push the locking element 22 back into the closed position since it knows from the signals received from the CPU 36 that the locking element 22 should be in the closed position and it can tell from the operation of the motor 16 that this is not the case.

The CPU 36 can be programmed to open or close, according to its programme, each of the locks 14 in the event of a power failure. For example, if an unauthorised person uncouples the cabinet 2 from the mains power supply the cabinet 2 can be arranged to lock each of the locks 14. This prevents access to the drawers 8 in these circumstances and thereby protects the contents of the cabinet 2. Alternatively, if preferred, the container can be arranged to fail in the open position, that is, in the event of power failure the locks 14 can be arranged to unlock. For example, if there is electrical power supply failure, users will still have access to the items stored within the cabinet 2 and so can continue working.

The cabinet 2 includes an electronic access system 54, for example of the type that includes a smartcard reader, a swipe card reader or token reader (proximity detector).

The access system 54 controls access to the drawers 8 and door 12 by providing appropriate data signals to the CPU 36 and the CPU 36 controls operation of the locks 14 to limit access to authorised users only.

Each authorised user is issued with an electronic card or token (hereinafter referred to as an identification device) which can be read by the reading device 54. When an authorised user is identified, the CPU 36 sends control signals to the locks 14 to open the drawers 8. The CPU 36 can be programmed to control access to the drawers 8 according to the access permissions granted to the user. For example, some users may only be allowed access to some of the drawers 8, and not to others. In this case, the authorised access information is stored in the identity device and this read by the reading device 54. Additionally, or alternatively, the authorised access information can be stored in a database that is accessible to the CPU 36. When the user is identified, the CPU 36 detennines which of the drawers 8 the user is authorised to access. It then sends the appropriate control signals via the bus 38 to the locking mechanisms 14 associated with the drawers 8 to allow the user access to those drawers. For those drawers 8 that the user does not have access to, the locks 14 will continue to maintain a locked state.

The cabinet 2 includes a lock button 56, which the authorised user operates in order to log off from the system. When the lock button 56 is pressed, the CPU 36 sends lock commands to each of the locks 14. On receipt of the lock command, each lock 14 determines via the open/close sensor 24 the open/closed status of the drawer 8 and acts according to its configuration. For example, if the sensor 24 indicates that one of the drawers 8 is open for one of the lock 14 having latch 38 then the PLC 18 can be arranged to move the locking element 22 into the lock position since the latch 38 enables the drawer to be closed when the locking element is in the locked position.

For locks 14 that do not include the latch 38, lock 14 is preferably arranged to retain the locking member 22 in the retracted position and reports a failure to the CPU 36.

The cabinet 2 may also include a alphanumeric input 58 for inputting data and an electronic display 60. Optionally, the cabinet 2 can include a tamper or shock sensor 62. This is arranged to determine if the cabinet 2 is subjected to abuse such as an attempt to force one of the drawers 8 open without authorisation.

The cabinet 2 also includes a non-volatile calendar clock 42, non-volatile memory 44.

The CPU 36 is arranged to record the identity of users, the time and date of logging into the system, the time and date of logging out of the system, the time and date of opening and closing of drawers and doors. The CPU 36 is preferably configured to record the identity of users even if access was refused in order to identify tamper attempts.

The cabinet 2 also includes a power monitoring device 46. The CPU 36 can be arranged to receive signals from the power monitoring device 45 and to control the sequence of operation of the locks 14 according to those signals to limit the peak output current required when unlocking the cabinet. The power monitoring device 45 is arranged to alert the CPU 36 of loss of mains power and/or critical low power states in order that the cabinet 2 can take action, for example to record the event and / or send a message to a central computer and / or illuminate a warning light.

The cabinet 2 includes a data link 48 such as an Ethernet, RS232 or ZigBee network connection. The data link 48 enables the connection of a portable computer, such as a laptop, from which recorded activity can be viewed and/or downloaded from the memory store 44 via a Web interface. The network connection also enables a plurality of cabinets to be connected to a single supervising computer, such as a server,. The supervising computer can be arranged to record cabinet activity for example via messages issued by the CPU 36 The messages can be store in a database application.

The supervising computer can be arranged to control and configure all cabinets connected to it.

The operation of the container will now be described with reference to Figures 5a and 5f. When a user approaches the cabinet 2, it may be in a Master Lock mode 66. If this is the case, it is necessary to unlock the cabinet 2 with a Master Lock key, which typically comprises an appropriately authorised identity device that is presented 68 to the reading device 54. The reading device 54 determines whether the identity device presented is appropriately authorised 70. If so, the CPU 36 switches out of the Master Lock mode 66 and records in the memory 44 the identity of the user, the date and time of access, the date and time being obtained from the calendar clock 42. If the identity device presented 68 is not appropriately authorised, the CPU 36 remains in Master Lock mode 66.

When the CPU 36 switches out of the Master Lock mode 66, it can either switch to a Normal Operation mode 92 or can enter into Visual Inventory Item Check mode 72, which in the example shown is a Visual Tool Check (VTC), if prompted to do so by a VTC schedule, which is programmed into the CPU 36. For example, the CPU 36 can be programmed to initiate the VTC at the beginning of a shift, during a shift, at the end of the shift, daily, and br weekly as required. The process requires the user to visually check that all of the inventory items that should be located within the inventory item cabinet, or at least to those drawers and cupboards to which the user has access, are present. The purpose of the verification process is to make the user take responsibility for checking that the inventory items are present, for example prior to a work shift commencing.

In the event that a VTC is required, the CPU 36 selects the VTC mode 72 and indicates 73 this to the user via an output device such as the LCD display 60 or illuminating a dedicated control, such as the verification button 64. The user may optionally be required to identify himself 74 at this stage by presenting his identity device to the reading device 54. In some embodiments, only a subset of users will be authorised to perform a VTC and therefore the system requests the user to identify himself to ensure that he is properly authorised 76 to perform the VTC. Assuming that a positive identification is made, the CPU 36 records in the memory 44 the identity of the user, the date and time of access, the date and time being obtained from the calendar clock 42, and the CPU 36 starts a timer 80, which provides a period of time for the user to complete the VTC. In this period, the user is required to open each of the drawers 6, according to the arrangement of the cabinet, in order to assess that each of the inventory items is present 82 in each of the drawers 6 and/or compartments 10.

The CPU 36 monitors output signals from the limit switches 24 in order to check that each drawer 6 is opened during the verification process. A record of the drawers 6 accessed during the period is stored in the memory 44. Optionally, the CPU 36 can be programmed to monitor the period of time for which each drawer 6 is open for during -the process to ensure that a reasonable period of time was spent assessing each drawer 6 and/or compartment 10. Optionally, the CPU 36 can be programmed to control the order in which the user accesses the drawers 6 and compartments 10 by controlling operation of the locks 14. For example, the CPU 14 can be programmed to unlock one drawer 6 at a time, and to relock that drawer 6 after the check has been made prior to unlocking the next drawer 6.

When the user has completed the VTC he presses 86 the verification button 64. The CPU 36 determines from the signals received from the limit switches 24, the status of the timer and internal logic, whether the VTC was validly performed within the period of time provided. If VTC is not validly completed within the time period, the CPU 36 is programmed to automatically lock 88 the cabinet by operating each of the locks 14, and then switches to the Master Lock mode 66. The cabinet 2 then requires a supervisor having Master Lock access to unlock the cabinet for further use. The VTC ensures that the user has all the appropriate inventory items for a particular job and that none of the inventory items are missing. If an inventory item is missing, a supervisor can investigate the matter with the previous user. This can be particularly important in the aerospace industry where foreign object damage to aircraft can be potentially catastrophic.

If the user identifies missing inventory items and therefore the cabinet 2 according to his judgement has not passed the VTC, the user can lock the cabinet 2 by pressing the lock button 56.

If the VTC is validly completed within the period the CPU extinguishes the illuminated verification button 64, or changes the LCD display 60, and switches to normal mode 92. Optionally, after the VTC has been completed, the CPU 36 can be arranged to lock the cabinet, thereby requiring each subsequent user of the cabinet to log in before inventory items and other inventory items are removed.

In normal mode 92, the user logs in by presenting 94 his identity device to the reading device 54. The CPU 36 determines from the information provided by the identity device the identity of the user and determines 96 the level of access that the user has with respect to the cabinet 2. The identity of the user is stored in the non-volatile memory 44 together with the time and date of access which are obtained from the non-volatile calendar clock 42. The CPU 36 sends unlock signals 98 to the locks 14 via the bus 38 to allow the user access to the drawers 6 andlor compartments 10 to which the user is authorised to access. The user then opens the drawer 6 to obtain 100 the desired inventory item or inventory item. The CPU 36 detects which drawer 6 has been opened by the user and records this in the memory 44, together with the time and date of opening of the drawer 6. The user removes inventory item and closes the drawer 6. The CPU 36 detects closure of the drawer 6 from the output signal from the associated limit switch 24. The time and date of the closure of the drawer is stored in the memory 44. The user then presses 102 the lock button 56, the CPU 36 sends lock signals to the locks 14 associated with the drawers 6 to which the user was authorised access. The cabinet 2 is now in a locked condition.

When the user has finished with the inventory item, he logs in again to replace the inventory item into the drawer, and logs out by pressing the lock button 56.

At the end of the shift, the CPU 36 determines 104 if a VTC is required. If so, the user logs in 106 and the CPU 36 determines 108 if the user is authorised to perform the VTC. If so, the VTC takes place in a similar manner to that described above.

Optionally, the cabinet 2 can include a computer (not shown) mounted on the cabinet.

The computer can provide the user with details of jobs to be performed, instruction manuals, tool lists, etc. The computer can be used for the purposes of maintaining a complete record of the job, including having a sign off procedure to certify that the work has been completed and the access record that is stored in the cabinet memory 44.

At the end of the shift, if scheduled, the CPU 36 can initiate 110 another VTC by switching to VTC mode 72.

It will be appreciated by the skilled person that the inventory item cabinet may take different forms: for example it may consist of a box with a single layer of inventory items, or with inventory items in removable trays, or it may take the form of a cupboard or a board on or within which the inventory items are hung, or any other suitable form. The inventory items may also of course be of any kind, including hand tools, engineering inventory items, machine bits, parts, surgical instruments and so on.

The invention may also be adapted to other non-inventory item applications, such as spare parts, electrical instruments, etc. where an inventory control system is required, and references within this specification to inventory items should be construed accordingly to include equivalent items in suitable non-inventory item applications.

Claims

CLAIMS1. Inventory item storage apparatus, including a plurality of separate storage sections, each storage section having an access member and a locking device arranged to selectively lock the access member to control access to the storage section; a user identification device for identifying authorised users; and a processing device for controlling operation of the locking devices independently of each other, wherein each locking device includes a motor and a locking member, said motor being arranged to move the locking member between a first operational position wherein the access member is unlocked and a second operational position wherein the access member is locked, wherein the processing device, in response to an authorised user logging into the system, is arranged to open the storage sections that the authorised user is authorised to access by operating the locking devices associated with those storage sections.
2. Apparatus according to claim 1, including a message bus, wherein each locking device includes a local processor for controlling operation of the motor and the processing device is arranged to communicate with each of the local processors via the message bus.
3. Apparatus according to claim 1 or 2, wherein the processing device is arranged to operate the locking devices sequentially.
4. Apparatus according to any one of the preceding claims, wherein at least some of the locking devices include a mechanism for converting a rotary output from the motor to linear movement of the locking member.
5. Apparatus according to any one of the preceding claims, wherein at least some of the access members include a locking formation and the locking member is arranged to selectively engage the locking formation.
6. Apparatus according to claim 5, wherein the locking formation includes a latching mechanism for engaging the locking member.
7. Apparatus according to any one of the preceding claims, including means for determining the operational status of the locking member.
8. Apparatus according to claim 7, wherein the means for determining the operational status of the locking member includes an encoder for monitoring the rotational position of the motor.
9. Apparatus according to any one of the preceding claims, wherein at least some of the access members have a sensor associated therewith, the sensor being arranged to detect the open and/or closed status of the access member.
10. Apparatus according to any one of the preceding claims, wherein each locking device includes a local indicator to visually display the locking status of the locking member.
11. Apparatus according to any one of the preceding claims, including non-volatile memory means.
12. Apparatus according to any one of the preceding claims, wherein the processing device is arranged to record the identity of the user.
13. Apparatus according to any one of the preceding claims, wherein the identification device includes at least one of the following: a card reader; a proximity reader; and / or an alphanumeric input system.
14. Apparatus according to any one of the preceding claims, including a master lock mode that prevents all standard users from accessing the storage sections until a user having a master lock identification device logs in and changes the status to a normal operational mode.
15. Apparatus according to claim 14 when dependent on claim 11, wherein the master lock mode status is stored in the non-volatile memory means.
16. Apparatus according to any one of the preceding claims, including a real-time clock wherein the processing device is arranged to record at least one of the following: the at which a user logs in, the time at which a user logs out, the time of opening of an access member and the time of closing an access member.
17. Apparatus according to any one of the preceding claims, wherein the processing device is arranged to initiate a verification process wherein the user is required to open each of the storage sections to which he has access and to check the presence and/or absence of each of the inventory items that should be stored in the storage sections.
18. Apparatus according to claim 16, wherein the processing device is arranged to initiate a timer at the start of the verification process that provides the user with a predetermined period of time to perform the verification process, and wherein if the verification process is not completed within the time period the processing device is arranged to operate the locking devices to lock the storage sections.
19. Apparatus according to claim 16 or 17, wherein the processing device is arranged to monitor output signals from sensors arranged to detect the opening and/or closing of the access members.
20. Apparatus according to any one of claims 17 to 19, wherein the processing device is arranged to control access to each of the storage sections accessible to the user during the verification process by controlling operation of the locking devices.
21. Apparatus according to any one of the preceding claims, including a data link for connecting a computer device to the processing device.
22. An inventory item verification process for inventory item storage apparatus comprising a plurality of storage sections each having an access member and a locking device arranged to selectively lock the access member; and a processing device arranged to control operation of the locking devices, said method including the processing device automatically initiating the verification process according to a predetermined schedule and indicating the start of the process to a user via an output device, and the user opening each of the storage sections to which he has access to check the presence and/or absence of inventory items that are stored in the storage sections.
23. A method according to claim 22, including the processing device initiating a timer at the start of the verification process and providing the user with a predetermined period of time to perform the verification process, wherein if the verification process is not completed within the predetermined time period, the processing device operating the locking devices to lock the storage sections.
24. A method according to claim 22 or 23, including the processing device monitoring output signals from sensors that are arranged to detect the open and/or closed status of the access members associated with the storage sections.
25. A method according to claim 24, including recording which storage sections are accessed by the user.
26. A method according to claim 25, including recording the period of time that each of the storage sections is accessed for.
27. A method according to any one of claims 22 to 26, including the processing device controlling the sequence in which each of the storage sections is accessible to the user by controlling operation of the locking devices.
28. A method according to claim 27, including controlling access to the storage sections such that only a single storage section can be verified at a time.
29. A method according to any one of claims 22 to 28, including providing a user identification device, and recording the identity of the user.
30. A method according to claim 29, including determining which of the storage sections the user is authorised to access and controlling the locking devices to limit access to those storage sections.