GB2471527A

GB2471527A - Code-operated lock

Info

Publication number: GB2471527A
Application number: GB0911607A
Authority: GB
Inventors: Desmond Michael Ryan
Original assignee: Codelocks Ltd
Current assignee: Codelocks Ltd
Priority date: 2009-07-03
Filing date: 2009-07-03
Publication date: 2011-01-05
Anticipated expiration: 2029-07-03
Also published as: GB0911607D0; GB2471527B

Abstract

A lock comprising code input means such as a keypad for input of codes (MC, SMC, LIC, RC), a memory for selectable storage of input codes, locking means transferable from a locking state to a release state in response to input by way of the input means of a code corresponding with a release code (RC) stored by the storage means, and programming means operable by the input means to cause the memory to store such a release code (RC) in response to sequential input of a lock identifying code (LIC) which identifies the lock and is stored by the memory and a further code selected to serve as the release code (RC), and to erase a currently stored release code (RC) in response to input of a change code comprising an erasure code (e.g. '99') stored by the memory. The lock may for example be used in a hotel whereby a hotel guest given the lock identification code can program their own lock release code and the release code can be deleted by a hotel manager or cleaner by entering a change code and the erasure code; the change code may comprise a master code or a submaster code held by a hotel manager or cleaner respectively. A master code may be used to reprogram codes of the lock such as changing the lock identification code.

Description

CODE-OPERATED LOCK

The present invention relates to a lock, especially to a lock of the kind operated by a code.

Locks of the kind commonly used for securing doors, gates and other access closures are increasingly employed in commercial, as distinct from domestic, applications in code-operated form so that keys do not have to be supplied to users. Such code-operated locks are particularly advantageous in situations where a relatively large number of persons is involved in operating a lock. It is then simpler and ultimately more economic to inform the users of a code number rather than provide individual users with keys.

A particular area of difficulty with respect to security, cost and convenience of locks is represented by door locks in hotels and other buildings with multi-room accommodation.

Historically, doors of hotel and similar rooms have been secured by conventional key-operated locks, which create problems if a key is misplaced or taken by a former occupant of the room. Security is then compromised until the lock is changed. This has led to the development of computer-based card-operated locks with programmable microprocessors operable by an insertable card. The loss of a card can then be dealt with by reprogramming the lock concerned and providing a new card co-operable with the code of the reprogrammed lock. These locks, although effective, are expensive and tend to be used primarily by larger hotels with greater resources.

There is, however, a worldwide requirement for a simpler, less expensive and more easily managed lock, particularly to satisfy the needs of smaller hotels, serviced apartments, hotels, holiday lets and other forms of accommodation with regularly changing room occupancy. A similar requirement arises in relation to locks for the doors of storage units, for example luggage lockers, ski lockers and other lockers commonly provided in bank form.

It is therefore the principal object of the present invention to provide a lock which operates on a code basis, thus without a key, card or any other form of separate actuating device, and which combines ease of use with the demands of security in such a manner that it is particularly suitable for applications in which operation is by multiple users, for example for the locking of doors of hotel rooms and other rooms with regular change of occupants or doors of lockers intended for use by members of the public.

A subsidiary object is to provide a lock of relatively economic construction, especially by drawing on established code-operated lock technology, so that it is more readily affordable by smaller hotels, hostels and similar establishments.

Other objects and advantages of the invention will be apparent from the following

description.

According to the present invention there is provided a lock comprising code input means for input of codes, code storage means for selectable storage of input codes, locking means transferable from a locking state to a release state in response to input by way of the input means of a code corresponding with a release code stored by the storage means, and programming means operable by the input means to cause the code storage means to (a) store such a release code in response to sequential input of both a lock identifying code which identifies the lock and is stored by the code storage means and a further code selected to serve as the release code and (b) erase a currently stored release code without affecting storage of the lock identifying code in response to input of a change code comprising an erasure code stored by the code storage means.

A lock embodying the invention has the advantage that the release code to which the locking means responds in order to change to its release state and thus allow opening of, for example, a room door secured by the lock can be freely selected by, in particular, an intended user of the lock and stored simply by input of the selected code in conjunction with a pre-stored code identifying the lock, The lock identifying code is a code uniquely -at least in relation to other such room door locks installed in the same building -denoting the specific lock. Although the user is able to select and store the release code, this action can be carried out only with knowledge of the lock identifying code and this knowledge can, until required by the user, be reserved to an authorised person, such as a party involved in the administration of the building with the room with which the lock is associated. When use of the lock by the user has concluded, for example, on departure of a hotel or hostel guest, the release code specific to that user can be erased by input of a change code consisting of or including a pre-stored erasure code, knowledge of which can again be reserved to an authorised party. The lock identifying code or a new lock identifying code remains in the code storage means and is thus available for performance of the release code storage procedure by a new user, who can freely select a new release code, but still has to gain knowledge of the currently stored lock identifying code.

Preferably, the locking means is additionally transferable from the locking state to the release state in response to the input of the lock identifying code and the further code on the occasion of storage of the latter as the release code. Thus, the act of storage of the release code also causes transfer of the locking areas to its release state, so that the user is not obliged to reintroduce the newly stored release code in order to open a door or other closure secured by the lock.

It is also desirable if the locking means is additionally transferable from the locking state to the release state in response to sole input of a code corresponding with a master code stored by the code storage means. An authorised party with knowledge of the master code, which at least at the outset can be a default code pre-stored by the lock manufacturer or supplier, thus retains overall control of access to a room or other facility with an access door secured by the lock. It is thus not necessary for the authorised party to have knowledge of the specific release code currently stored by the storage means.

The master code, as implied by the designation, can be used not only for transfer of the locking means to its release state, but preferably also for programming and reprogramming functions connected with the storage content of the code storage means.

Thus, for example, the change code to be input in order to erase the release code can be composed of the master code and the erasure code in sequence, both codes being permanently retained by the code storage means.

For preference, the programming means is also operable to change the stored master code in response to input of a change code comprising the currently stored master code, an overwrite code stored by the code storage means and a new master code in sequence.

The default master code programmed into the lock by the manufacturer or supplier can thus be changed, again only by an authorised party with knowledge of the default master code or any subsequent replacement, to a preferred alternative or to a substitute code if necessary to avoid compromise to security, for example if knowledge of the master code has been gained by an unauthorised party. For enhanced certainty in the procedure for changing the master code, the change code for this purpose preferably includes a final repeat of the new master code, which provides confirmation that no error has been made in input of the new master code, since an error could otherwise lead to storage of a master code not corresponding with that intended by the authorised party and consequently not actually known to the authorised party unless the erroneously stored code is remembered.

In practice it is of advantage if the locking means is additionally transferable from the locking state to the release state in response to sole input of a code corresponding with a submaster code stored by the code storage means, the submaster code having less capability in relation to operation of the lock than the master code. In the example of a hotel, knowledge and use of the submaster code can be granted to a hotel employee, such as a member of cleaning staff, with a need for independent access to various rooms for cleaning or servicing purposes. The reduced capability of use of the submaster code by comparison with the master code preferably means that the submaster code cannot be used for at least some reprogramming actions involving the lock, such as changing the lock identifying code or the master code. However, it can be advantageous for the submaster code to be usable for erasure of the release code, in which case the change code for this erasure is preferably composed of either the master code or the submaster code in sequence with -for preference preceding -the erasure code. In the mentioned example of a hotel and use of the submaster code by cleaning staff, a member of the staff can, at the time of gaining access to and servicing a room, employ the submaster code not only for access, but also for erasure of the release code stored by a previous occupant of the room, so that the lock is then ready for installation of a new release code selected by the next occupant.

If the locking means is to be responsive to such a submaster code, the programming means is preferably also operable to cause the code storage means to store the submaster code or change the stored submaster code in response to input of a code comprising the stored master code, a write/overwrite code stored by the code storage means and a submaster code or new submaster code in sequence. The write/overwrite code used for submaster code initial storage or change is again a code pre-stored by the lock manufacturer and supplier. Change of the submaster code may be desirable to enabie restoration of optimum security if a situation arises in which there is scope for misuse of the submaster code, for example if a member of staff with knowledge of the submaster code leaves employment or otherwise ceases to have authorisation to use the code. In similar manner to the procedure for change of the master code, the procedure for storage or change of the submaster code can entail use of a code having a final repeat of the new submaster code as a precaution against inadvertent storage of an incorrect code, If the submaster code is no longer needed, provision can be made for its erasure, in particular the programming means can be operable to erase the stored submaster code in response to input of the submaster code and an erasure code pre-stored in the code storage means.

For preference, the programming means is operable to cause the storage means to erase the currently stored release code without affecting storage of the lock identifying code.

The lock identifying code is consequently subject to, in effect, permanent storage, as opposed to the merely transient storage of the release code. It is then advantageous if the programming means is operable to cause the storage means to store the lock identifying code or change the stored lock identifying code in response to sequential input of an installation code comprising a write/overwrite code stored by the code storage means and of a code selected to serve as the lock identifying code. This feature allows an authorised party to install the lock identifying code at the time of, for example, fitting the lock to a door so that the code can be linked to the door or the faciUty associated with the door. Thus, if the door is that of a hotel room, the lock identifying code can also identify, but preferably not be identical with, the number of the room. The lock identifying code can be changed at any time by the same procedure, in particular use of the installation code which consists of or includes the write/overwrite code. This latter code is pre-stored in the code storage means by the lock manufacturer or supplier and, for example, notified in or in conjunction with installation and operating instructions. It is particularly advantageous if the installation code for the lock identifying code is composed of the pre-stored master code and the pre-stored write/overwrite code in sequence.

In an alternative embodiment the programming means is operable to cause the storage means to store a provided lock identifying code in response to sequential input of the master code -or submaster code if this is also stored -and the erasure code. In that case enhanced security coupled with automation of an otherwise manual action can be achieved if the lock additionally comprises a random code generator to provide a random code as the lock identifying code in response to the sequential input of the master code or submaster code, as the case may be, and the erasure code. Thus, on each occasion of entry of the master or submaster code in conjunction with the erasure code there is automatic generation of a randomly selected lock identification code and storage of that code in place of the previously stored lock identification code. It is only necessary to make a record of the generated and automatically stored new lock identification code so that it can be notified to the next intended user wishing to store a release code.

The codes are, for preference numerical, especially multi-digit numbers, but can be letter or even symbol codes, or combinations of numerals and letters. It is preferable for the principal codes, i.e. release code and, when provided, master and submaster codes, to be formed by greater numbers of digits than the remaining codes, i.e. the lock identifying code and erasure, write and write/overwrite codes. Codes in the former category can be, for example, four-digit codes and those in the latter category, for example, two-digit codes.

The number of digits making up a code to which the locking means and code storage means respond is predetermined by the programming means.

It is advantageous if the locking means is arranged to remain in its release state for and only for a predetermined period of time after transfer to that state. After that time, the locking means can then be automatically returned to its locking state, which should not, however, impede closing of a door or other closure to which the lock is fitted and which is still open at the time of return of the lock to its locking state.

The practical realisation of the lock can be achieved by diverse forms of embodiment, in one advantageous example of which the lock comprises code recognition means for recognition of codes input by way of the input means, signal generating means responsive to code recognition by the code recognition means to generate a signal and actuating means responsive to the signal to cause or allow transfer of the locking means from the locking state to the release state. The actuating means can be, for example, an electric motor operable to cause or allow displacement of a latch of the locking means. The storage means can take the form of a simple selectively erasable and writable memory, the code storage, change and recognition functions preferably being executable by a programmable microprocessor associated with the memory and the signal generating means.

The code input means is, for preference, a keypad realised with discrete buttons, a touch-sensitive screen or any other simple, but preferably robust, input arrangement. The lock can additionally include indicating means for indicating transfer of the locking means to its release state, for example by way of an optical or acoustic signal output of a kind commonly associated with a change of state or the unlocking of a lock, and preferably also indicating means for indicating input of a lock identifying code or release code not corresponding with, respectively, the stored lock identifying code or the stored release code. It is also advantageous if the lock has an own electrical power source, such as a battery. The locking means can, in addition, be capable of key actuation for transfer from the locking state to the release state so that if a fault should arise with the code-based actuation an emergency operation of the locking means is possible. Alternatively, the lock can comprise a latch actuable by the locking means and also capable, should it be required, of key activation.

In another aspect there is provided a method of operating a lock as claimed in any one of the preceding claims, the lock being associated with an access door of a facility intended to have a changing user and the method comprising the steps of storing the release code in the storage means by sequential input by way of the input means of the lock identifying code and a further code selected by a user of the facility and intended to serve as the release code and of erasing the stored release code from the storage means, when use of the facility by the user has ceased, by input of the change code by way of the input means.

In such a method the lock is fitted to a door or the frame of a door of a room providing accommodation for the user and intended to have changing occupancy, a storage unit, such as a locker intended for temporary storage of items deposited by different users, or another such facility with changing users, and allows the user, to whom knowledge of the respective lock identifying code has been imparted, to select and store a release code chosen by and thus known only to the user. At the conclusion of use of the facility by a particular user, the stored release code specific to that user is erased, preferably by and only by an authorised party, so as to prepare the lock to accept a new release code chosen by the next user. The release code can be a multi-digit personal identification number of the user, but also part of a telephone number or any other combination of digits the user may find convenient to remember.

If the lock includes a stored master code able to be changed by operation of the programming means, the method can also include a step of changing the stored master code by sequential input by way of the input means of the stored master code, the overwrite code and a code selected by an authorised person to serve as the new master code. Similarly, if the lock allows storage or change of a submaster code in the code storage means by operation of the programming means this code can be stored or changed by sequential input by way of the input means of the stored master code, a write/overwrite code and a code selected by an authorised person to serve as the submaster code or new submaster code, The stored submaster code is preferably capable of erasure by input, by way of the input means, of a specific erasure code stored in the code storage means.

In a case where the programming means of the lock is operable to cause the storage means to store the lock identifying code or to change the stored lock identifying code the method preferably includes a step of initially storing that code or changing that stored code by sequential input by way of the input means of the installation code and a code selected by an authorised person to identify the facility and to serve as the lock identifying code.

Thus, if the lock is fitted to, for example, a hotel room door the lock identifying code can be linked with the number of the specific room, but for reasons of security should preferably not be identical with the room number. It is then only necessary for an authorised person, such as a hotel manager in the case of the example of fitting the lock to a hotel room door, to retain a list giving the association of lock identifying codes with room numbers.

In an alternative case where the programming means is operable to cause the storage means to store a provided, for example, randomly generated, lock identifying code in response to sequential input of the master code -or submaster code if stored -and the erasure code the method then preferably comprises the step of causing this storage to take place by user input, by way of the input means, of the respective master or submaster code and the erasure code. An authorised person can thus constantly update the lock identification code without having to personally make a code selection. The regular change of the lock identification code increases the security of the lock operation as a whole.

A preferred embodiment of the lock and example of the method will now be more particularly described with reference to the accompanying drawings, in which: Fig. 1 is a schematic front view of a lock embodying the invention; and Fig. 2 is a flow chart illustrating steps in operation of the lock by a method exemplifying the invention Referring now to the drawings there is shown in Fig. 1, in an arbitrary configuration, a code-operated lock 10 comprising a housing 11 containing a locking mechanism, of which merely a protruding latch 12 is depicted. The locking mechanism is transferable between a locking state in which the latch 12 protrudes as shown and a release state in which the latch is or can be retracted into the housing 11 The housing is fitted to a door 13 surrounded by a door frame 14, which has a recess 15 in which the latch 12 engages in the locking state. The lock can also be equipped with a handle 16. It is, of course, possible to reverse the relationship and fit the lock to the frame so that the latch then engages in a recess in the door.

Also present within the housing 11, but not illustrated, are programming and storage means such as a microprocessor incorporating a memory into which numerical codes can be written and stored and from which stored codes can be erased. Input of numbers to create codes is by way of a keypad 17 which has ten numerical and two symbol push buttons acting on microswitches and which is arranged on a front face of the housing.

Storage of codes input via the keypad is carried out by actuation of numerical buttons corresponding with a code which is pre-stored in the memory and to which the programming means responds to enter a programming mode, after which codes can be stored in the memory by button actuation as explained by way of example further below.

The microprocessor further comprises code recognition means for recognition of input codes matching already stored codes and includes or is associated with a signal generator for generation of an actuation signal in response to recognition of code matches predetermined to be effective to initiate transfer of the locking means from its locking state to its release state. Also present in the housing is an actuator, for example an electric motor acting on a clutch and spindle, responsive to the actuation signal to actuate the locking mechanism for transfer thereof to the release state. Transfer back to the locking state can be by way of reverse operation of the actuator, by restoring spring or by any other desired method after elapse of a predetermined time period, for example five seconds.

The specific form of locking mechanism and actuator can be as desired. The microprocessor can be constructed in accordance with established principles and the operating power for the microprocessor, actuator and any other current consumers of the lock is supplied from an own power source, such as a battery or storage capacitor and photocell. As a safeguard against loss of operating capability of the lock 10 due to electronic/electrical component failure or exhaustion of the power source the lock can incorporate a key override 18 by which the locking mechanism, or the latch 12 directly, can be operated. Additionally or alternatively, terminal extensions can be included to permit application of an emergency power source, such as a battery. Arranged at the housing exterior is an optical indicator 19 which, under the control of the microprocessor or the generated signal, illuminates when the locking mechanism is transferred to the release state. A further indicator 20 can be provided to indicate input of codes which are intended to match the codes effective to initiate transfer of the locking means to its release state, but which are incorrect.

The illustration and description of the lock are merely by way of example and, apart from its described functional capabilities, its appearance and physical construction can be varied within wide parameters, including provision for mounting on either the door or the frame. The lock can be employed to secure other forms of closures, such as gates and windows, but it is particularly suitable for doors, especially doors of rooms in commercial establishments such as hotels, guest houses, hostels, serviced apartments and holiday flats, and doors of storage units, such as banks of lockers for storing luggage, ski equipment and other articles.

Fig. 2 shows, by way of example, a table of codes pre-stored in the lock memory and a procedure for operating the lock 10 with particular emphasis on initial storage of basic operating codes or change of stored basic operating codes and on storage and erasure of a release code serving to unlock a door equipped with the lock as well as use of the stored release code for that purpose. The steps illustrated in Fig. 2 do not necessarily depict the full range of operating capabilities of the lock, but only principal capabilities. The lock operation is described in the following by the non-limitative example of a lock fitted to the door of a hotel room, with the assumption that the room occupant regularly changes and that supervision of the room is performed by the hotel administration, represented by a hotel manager or receptionist and one or several cleaning staff.

The table on the left in Fig. 2 shows codes pre-stored in the lock memory by the manufacturer or supplier of the lock, namely a default master code arbitrarily represented by the four-digit number 1234' and command codes arbitrarily represented by the two-digit numbers 11' for changing the master code, 22' for installing or changing a submaster code, 33' for erasing a stored submaster code, 44' for installing or changing a lock identifying code and 99' for erasing a stored release code. The master code, knowledge and use of which is normally reserved to an authorised party responsible for the lock, for example the hotel manager, is intended to permit modification of the memory content to the full extent permitted and also unlocking of the door. Accordingly, the code programming means and code recognition means of the microprocessor respond to input of the master code either by itself to cause generation of the actuation signal leading to transfer of the locking means from the locking state to its release state and also opening the programming mode (whether needed or not) or in sequence with a selected one of the command codes, in particular preceding a command code, to not only cause generation of the actuation signal and opening of the programming means, but also to permit a specific change in memory content depending on the command code selected. The submaster code, which is known to the hotel manager, but also made known to and used by a member of cleaning staff, is usable in the same way as the master code, but, with respect to changing the memory content, only in conjunction with the command code for erasure of a stored release code. The lock identifying code uniquely identifies the lock and, by extension, the room with the door to which the lock is fitted. Knowledge of the lock identifying code is communicated by the hotel manager or receptionist to an intended occupant of the room to enable the occupant to store a release code. The release code is thus a code selected by and stored, with the use of the lock identifying code, by the occupant independently of the hotel administration. The code recognition means of the microprocessor responds to input of a code matching a stored release code to cause generation of the actuation signal producing transfer of the locking means to its release state, thus unlocking of the door. Knowledge of the release code is therefore reserved to the occupant and can be, for example, a personal identification number, part of a telephone number or birth date, or any other number which the occupant may find easy to remember. If the occupant cannot readily remember a number of such kind, the hotel administration can suggest a repetitive or ascending/descending numeral combination or similar.

The sequence of lock operating steps shown in Fig. 2 does not constitute a continuous sequence as such, but a series of discrete steps of the kind performed in operation of the lock and in an order in which they are generally carried out at least after installation of the lock. However, depending on requirements the order may be varied as desired insofar as performance of a step does not depend on prior performance of one or more of the other steps.

In the first illustrated step, denoted by 22, an optional change of the default master code 1234' is performed to substitute a code which may be preferred by the hotel manager, in this example arbitrarily 4567', and which ensures that the master code will be specific to the lock. The change is made by input, by way of the keypad buttons designated by the corresponding numerals, of a number sequence composed of the default master code 1234', the associated change code 11', the new master code 4567' and, to confirm correct entry of the selected replacement master code, the master code 4567' once again.

On input of the default master code 1234' the code recognition means and code programming means in the microprocessor cause generation of the actuation signal to transfer the locking means to its release state and simultaneously open the programming mode to allow change of the memory content. The same occurs on each subsequent occasion of input of the current master code, i.e. 4567'. Unlocking of the door as a consequence of transfer of the locking means to its release state is indicated by the step 23.

If the door is to be unlocked at any time by the hotel manager or other authorised party, use can be made of the master code 4567' (previously 1234') by itself, as indicated by step 24.

In some circumstances, such as that of use of the lock on a hotel room door, it would be desirable to install a submaster code, with the function already described, in the lock memory. A submaster code, for example 4321', can accordingly be installed as indicated in step 25 by input of the master code 4567', which as already stated both unlocks the door and opens the programming mode, followed by the associated installation change code 22' and then the desired submaster code 4321' twice in succession. Thereafter, the door can also be unlocked by input of a code corresponding with the stored submaster code 4321', as indicated in step 26. If the submaster code is no longer required, it can be erased as indicated in step 27 by input of the master code 4567' followed by the associated erasure code 33'. If a submaster code is to be retained, but changed to a different number, this can be achieved by repeating step 25, the code 22' being a write/overwrite code serving for both initial installation and subsequent change.

As a final step in programming the lock for operation, a lock identifying code, for example 27', is installed in step 28 by input of the current master code 4567' followed by the associated installation or change code 44' and the selected lock identifying code 27'. The locking identifying code 27' may, for example, denote room number 10 in a hotel and be able to associated with that particular room by way of a list of room/code associations retained by the hotel manager or receptionist. The stored lock identifying code can be changed at any time by repeating the step 28, the code 44' providing a write/overwrite instruction to the memory.

The lock memory is now programmed to the extent necessary for operation, steps 22 and 24 to 28 having been performed by an authorised person. When the room associated with the lock is allocated to an intended occupant, the occupant is notified of the lock identifying code 27' and, with this information, is in a position to store a release code, chosen by the occupant, in the lock memory. This action is undertaken in step 29 by input of the lock identifying code 27' followed by the selected release code, for example 8214'.

Completion of step 29 both unlocks the door and has the effect that the code recognition means of the microprocessor will thereafter recognise sole input of a code corresponding with the stored code 8214' and cause generation of the actuation signal to transfer the locking means to its release state and thus unlock the door. This action is indicated by step 30, which necessarily has to be preceded by step 29. The occupant thus has the facility of unlocking the room door by use of a personal code without any requirement for possession and use of a key or card.

At the conclusion of use of the room by the occupant, the release code selected by and therefore specific to that occupant has to be erased from the lock memory. This is carried out in step 31 by input of either the master code 4567' or submaster code 4321' followed by the erasure code 99'. The door is now unlockable only by way of the master or submaster code (step 24 or 26). On arrival of a new occupant, step 29 is repeated in the form shown in step 32, namely storage of a new release code, for example 7465' selected by the new occupant by input of the lock identifying code and the new release code in that order. Thereafter, the steps 30, 31 and 32 are repeated in the course of use of the room by the current occupant, eventual departure of that occupant and arrival of a new occupant.

Although following step 31 the lock is, in effect, primed to accept a new release code it may be expedient in some situations, for example if a room is left vacant for a longer than normal period of time or if optimum security is desired, for hotel staff to intermediately store an arbitrary release code. This ensures that a departed occupant who has acquired knowledge of the system and, in particular, the lock identifying code specific to the room concerned cannot return in the interim and unlock the door by storing a release code by the procedure of step 32.

In a further embodiment the lock 10 includes a random number generator in conjunction with the programming and storage means within the housing 11, and also a display unit, for example a liquid crystal display, which is operatively connected with the generator and has a screen 21 incorporated in the housing front face and serving for display of lock identification codes each time the master or submaster code is entered. The random number generator is responsive to input of the current master code or submaster code followed by the erasure code to automatically generate a new, randomly determined lock identification code number, which the programming means then stores in place of a currently stored lock identification code. The lock identification code is thus updated on every occasion of input of the master or submaster code in conjunction with the erasure code, thus the step 31 in Fig. 2 for erasure of a release code. The step 28, relating to installation of a lock identification code, is effectively redundant, since installation takes place automatically. An authorised user entering the master or submaster code in conjunction with the erasure code is required to note a newly provided and stored lock identification code so that this can be communicated to a lock user, for example new room occupant, wishing to enter a release code. The currently stored lock identification code, whether pre-existing or newly provided, is displayed for a brief period of time on the screen 21 on each occasion of entry of the master or submaster code followed by the erasure code for erasing the release code. The authorised user thus has an opportunity to note the new lock identification code, but if noting the code is missed it is only necessary to re-enter the master or submaster code to cause the lock identification code to be displayed again on the screen 21.

Operation of the lock is otherwise essentially the same as in the case of the first-described embodiment. When the step 31 is performed to erase the stored release code of a departed room occupant the entry of the master code 4567' (or submaster code 4321') and erasure code 99' will not only erase the release code, but also generate a new, randomly determined lock identification code and display and store that code. A new room occupant can store a desired release code as indicated in step 32 and thereafter unlock the door by input of just that code. The randomly generated lock identification codes produced by the random number generator can be, for example, three-digit or four-digit codes.

The display 21 can also be connected to the programming means and operable to provide acknowledgements or instructions to a user, for example a positive message such as OK' in response to entry by way of the input means of the correct lock identification code or a negative message in the case of entry of an incorrect code entry.

A lock embodying the invention has the advantage that it eliminates the need for keys or cards and functions on a code-operated basis using a code chosen by the user, such as a hotel room occupant, but effective only with knowledge imparted by an authorised person, such as a member of the hotel staff. This provides a two-layer level of security allowing overall control by the authorised party, yet grant to the user of individual control of the lock operation.

Claims

CLAIMS1. A lock comprising code input means for input of codes, code storage means for selectable storage of input codes, locking means transferable from a locking state to a release state in response to input by way of the input means of a code corresponding with a release code stored by the storage means, and programming means operable by the input means to cause the code storage means to (a) store such a release code in response to sequential input of both a lock identifying code which identifies the lock and is stored by the code storage means and a further code selected to serve as the release code and (b) erase a currently stored release code in response to input of a change code comprising an erasure code stored by the code storage means.
2. A lock as claimed in claim 1, wherein the locking means is additionally transferable from the locking state to the release state in response to the input of the lock identifying code and the further code on the occasion of storage of the latter as the release code.
3. A lock as claimed in claim 1 or 2, wherein the locking means is additionally transferable from the locking state to the release state in response to sole input of a code corresponding with a master code stored by the code storage means.
4. A lock as claimed in claim 2, wherein the change code for erasure of the release code comprises the master code and the erasure code in sequence.
5. A lock as claimed in claim 3 or claim 4, the programming means being operable to change the stored master code in response to input of a change code comprising the currently stored master code, an overwrite code stored by the code storage means and a new master code in sequence.
6. A lock as claimed in claim 5, wherein the change code for the master code further comprises a final repeat of the new master code.
7. A lock as claimed in any one of claims 3 to 6, wherein the locking means is additionally transferable from the locking state to the release state in response to sole input of a code corresponding with a submaster code stored by the code storage means, the submaster code having less capability in relation to operation of the lock than the master code.
8. A lock as claimed in claim 7, wherein the change code for erasure of the release code comprises the master or submaster code and the erasure code in sequence.
9. A lock as claimed in claim 7 or claim 8, the programming means being operable to cause the code storage means to store the submaster code or change the stored submaster code in response to input of a code comprising the stored master code, a write/overwrite code stored by the code storage means and a submaster or new submaster code in sequence.
10. A lock as claimed in claim 9, wherein the code for storing or changing the submaster code further comprises a final repeat of the new submaster code.
11. A lock as claimed in any one of claims 7 to 10, the programming means being operable to erase the stored submaster code in response to input of the master code and an erasure code stored by the code storage means.
12. A lock as claimed in any one of the preceding claims, the programming means being operable to cause the storage means to erase the currently stored release code without affecting storage of the lock identifying code.
13. A lock as claimed in claim 12, the programming means being operable to cause the storage means to store the lock identifying code or change the stored lock identifying code in response to sequential input of an installation code comprising a write/overwrite code stored by the code storage means and of a code selected to serve as the lock identifying code.
14. A lock as claimed in claim 13 when appended to any one of claims 3 to 11, wherein the installation code for the lock identifying code comprises the master code and the write/overwrite code in sequence.
15. A lock as claimed in any one of claims 3 to 11, the programming means being operable to cause the storage means to store a provided lock identifying code in response to sequential input of the master code and the erasure code.
16. A lock as claimed in claim 15 when appended to any one of claims 7 to 11, the programming means being operable to cause the storage means to store a provided lock identifying code in response to sequential input of the submaster code and the erasure code.
17. A lock as claimed in claim 15 or claim 16, comprising a random code generator to provide a random code as the lock identifying code in response to sequential input of the master code or submaster code, as the case may be, and the erasure code.
18. A lock as claimed in any one of the preceding claims, wherein the codes are numerical.
19. A lock as claimed in claim 18, wherein the codes are multi-digit numbers.
20. A lock as claimed in any one of the preceding claims, the locking means being arranged to remain in its release state for and only for a predetermined period of time after transfer to that state.
21. A lock as claimed in any one of the preceding claims, comprising code recognition means for recognition of codes input by way of the input means, signal generating means responsive to code recognition by the code recognition means to generate a signal and actuating means responsive to the signal to cause or allow transfer of the locking means from the locking state to the release state.
22. A lock as claimed in any one of the preceding claims, wherein the input means comprises a keypad.
23. A lock as claimed in any one of the preceding claims, comprising indicating means for indicating transfer of the locking means from the locking state to the release state.
24. A lock as claimed in any one of the preceding claims, comprising indicating means for indicating input of a lock identifying code or release code not corresponding with, respectively, the stored lock identifying code or the stored release code.
25. A lock as claimed in any one of the preceding claims, wherein the lock has an own electrical power source.
26. A lock as claimed in any one of the preceding claims, wherein the locking means is additionally capable of key actuation for transfer from the locking state to the release state.
27. A lock as claimed in any one of claims 1 to 25, comprising a latch actuable by the locking means, the latch being capable of key actuation.
28. A method of operating a lock as claimed in any one of the preceding claims, the lock being associated with an access door of a facility intended to have a changing user and the method comprising the steps of storing the release code in the storage means by sequential input by way of the input means of the lock identifying code and a further code selected by a user of the facility and intended to serve as the release code and of erasing the stored release code from the storage means, when use of the facUlty by the user has ceased, by input of the change code by way of the input means.
29. A method as claimed in claim 28, wherein the step of erasing is performable by and only by an authorised person.
30. A method as claimed in claim 28 or claim 29, wherein the release code is a multi-digit personal identification number of the user.
31. A method as claimed in any one of claims 28 to 30, wherein the lock is as claimed in claim 5 and the method comprises the step of changing the stored master code by sequential input by way of the input means of the stored master code, the overwrite code and a code selected by an authorised person to serve as the new master code.
32. A method as claimed in any one of claims 28 to 31, wherein the lock is as claimed in claim 9 and the method comprises the step of storing the submaster code or changing the stored submaster code by sequential input by way of the input means of the stored master code, a write/overwrite code and a code selected by an authorised person to serve as the submaster code or new submaster code.
33. A method as claimed in claim 32, comprising the step of erasing the stored submaster code by input by way of the input means of an erasure code stored in the code storage means.
34. A method as claimed in any one of claims 28 to 33, wherein the lock is as claimed in claim 13 and the method comprises the step of initially storing the lock identification code or changing the stored lock identifying code by sequential input by way of the input means of the installation code and a code selected by an authorised person to identify the facility and to serve as the lock identifying code.
35. A method as claimed in any one of claims 28 to 33, wherein the lock is as claimed in claim 15 and the method comprises the step of causing storage of the provided lock identification code by sequential input by way of the input means of the master code and the erasure code.
36. A method as claimed in any one of claims 28 to 33, wherein the lock is as claimed in claim 16 and the method comprises the step of causing storage of the provided lock identification code by sequential input by way of the input means of the submaster code and the erasure code.
37. A method as claimed in any one of claims 28 to 36, wherein the facility is a room.
38. A method as claimed in claim 37, wherein the room is a room providing accommodation for the user.
39. A method as claimed in any one of claims 28 to 38, wherein the facility is a storage unit providing storage for an item deposited by the user.
40. A method as claimed in claim 39, wherein the storage unit is a locker.