[0001] This invention relates to programmable security locks and is particularly applicable
to such locks for providing restricted access in hotels, commercial offices, industrial
complexes and the like.
[0002] Programmable door locks are finding increased use throughout the world and are being
used in some large hotels, where security can be an increasing problem, a programmable
lock being provided for each of the hotel rooms. When a new guest registers at a hotel,
a particular room is allocated to him/her and the programmable door lock to the room
is coded with a unique code which would be applicable for the duration of the guest's
stay. The guest is also provided with an "electronic key" which is coded with the
same unique code and this allows the guest access to the hotel room when the key is
inserted in the programmable door lock. When the guest checks out of the hotel, the
programmable door lock is re-programmed with a different code so that the electronic
key allocated to the departing guest no longer operates the lock of the hotel room
which had been allocated to him/her. The "electronic key" may take a variety of forms
and may be constructed in the form of a thin strip of card or plastic, similar to
a cheque card, and the code may normally be stored, for example, on a magnetic strip
contained on the key or it may be electronically or optically stored within the body
of the key or stored in the form of physical holes or deformations on part of the
key.
[0003] It is an object of the present invention to provide an improved form of programmable
door lock.
[0004] According to one aspect of the present invention there is provided a programmable
security lock which is remotely programmable with a security code which controls the
opening thereof, said lock comprising an electronic key which is programmable with
a security code which corresponds to the security code of said lock, and means for
remotely interrogating the security code of said electronic key for the purpose of
opening said lock.
[0005] In a preferred arrangement said electronic key will comprise a transponder arrangement,
in which case said lock may comprise means for transmitting an interrogating signal
to said electronic key and means for receiving a transponding signal from said electronic
key, said transponding signal being indicative of the security code of said electronic
key.
[0006] Advantageously, said lock comprises memory means for storing the security code of
said lock, and processor means for comparing the security code of the received transponding
signal from said electronic key with the security code of said memory means and for
causing a lock mechanism of said lock to be opened when said security codes correspond.
[0007] It may be arranged that said means for receiving a transponding signal is also effective
for receiving a programming signal indicative of the security code to be programmed
into said lock, said processor means being operable in response to said programming
signal for causing the security code thereof to be stored in said memory.
[0008] In a preferred arrangement according to the present invention a remote lock controller
may be provided which includes means for transmitting said programming signal, and
means for receiving a signal transmitted from said lock.
[0009] It may be arranged that said lock comprises means for transmitting an alarm signal
to said remote lock controller when said security codes do not correspond, or alternatively
for transmitting said security code of a received transponding signal to said remote
lock controller.
[0010] The security code of each received transponding signal may be stored in said memory
means, and the security codes stored in said memory means transmitted to said remote
lock controller, in which latter case the security codes stored in said memory means
may be transmitted to said remote lock controller at predetermined time intervals,
or in response to a signal received therefrom.
[0011] Actuating means may be provided for causing said means for transmitting said interrogating
signal to said electronic key to be operated, said actuating means conveniently comprising
a door handle, e.g. of a door on which said lock is mounted.
[0012] Preferably, said electronic key comprises memory means for storing the security code
of said key, means for receiving the interrogating signal from said lock and means
for transmitting a transponding signal indicative of the security code stored in the
memory means of said key.
[0013] According to another aspect of the present invention there is provided an electronic
key for use with a programmable security lock according to said first aspect.
[0014] An exemplary embodiment of the invention will now be described reference being made
to the accompanying drawings, in which:
Figure 1, is a block schematic diagram of a hotel access control system incorporating
a plurality of programmable security locks according the present invention;
Figure 2, is a diagrammatic perspective view of a programmable door lock in accordance
with the present invention for use in the system of Figure 1;
Figure 3, is a block schematic diagram of the programmable door lock of Figure 2;
and
Figure 4, is a block schematic diagram of an electronic key for use with the programmable
door lock of Figures 2 and 3.
[0015] The exemplary embodiment of the invention to be described is based on use in a hotel
access control system such as that which is described in U.K. Patent Application Publication
No. 2236354A. However, it should be appreciated that the invention has much wider
application and may be used, for example, within commercial, industrial, business,
sports and leisure environments.
[0016] The access control system which is to be described is based on the use of a programmable
door lock which is fitted to each of the rooms of a hotel, each of the door locks
being programmed with a unique code such that it can only be opened, to gain access
to the room, by an electronic key which is coded with the same unique code.
[0017] In Figure 1 of the drawings there is shown a hotel access control system which comprises
a control unit 1 which is typically located on or near the hotel reception desk. Each
of the rooms of the hotel is fitted with a programmable door lock 2, and each guest
of the hotel is provided with an electronic key 3, in the form of a "smart" card and
similar to a thin pocket calculator, for gaining access to the room which has been
allocated to him/her.
[0018] The control unit 1 comprises a reception check-in console 4, a key and lock programmer
5 and a transmitter/receiver Tx/Rx 6.
[0019] When a new guest checks into the hotel, the receptionist identifies a suitable room
for the guest via the check-in console 4 which also generates a suitable security
code which is to be allocated to that particular room for the period that the room
is to be allocated to the new guest. The code generated by check-in console 4 is fed
to the key and lock programmer 5 into which is inserted the electronic key 3 which
is to be allocated to the new guest. The key and lock programmer 5 codes the electronic
key 3 with the required code and the code is also fed to the transmitter/receiver
6 where it is transmitted via aerial 7 to the programmable door lock 2, via its aerial
8, of the room which has been allocated to the new guest. The coded electronic key
3 is then issued to the new guest which enables him/her to gain access, as will hereinafter
be described, only to the room which has been allocated to him/her. Other areas of
the hotel which are provided only for the benefit of hotel guests, such as gymnasiums,
saunas, swimming pools, etc. may also be provided with programmable door locks 2,
which may be programmed such that any guest having a valid electronic key can gain
access thereto.
[0020] In Figure 2 of the drawings there is shown a diagrammatic view of a programmable
door lock 2 which is attached to the door 9 of a hotel room. An electronic key 3 is
also depicted for opening the lock 2 as will be described. The lock 2 comprises a
door handle 10, the spindle of which is provided with a cam 11 which, when the handle
10 is turned, causes a microswitch 12, or other suitable switch, to be operated. The
output from the microswitch 12 is applied to an access control module 13 which will
be described in greater detail with reference to Figure 3. The access control module
13 is powered from a battery 14 and is connected to the antenna 8 (Figure 1) and to
the solenoid 15 of a lock mechanism 16. The lock mechanism 16 is provided with a protruding
door catch 17 which normally locks the hotel door closed but which is retracted when
the solenoid 15 of the lock mechanism 16 is activated to release the door.
[0021] In Figure 3, the access control module 13 of Figure 2 is shown in greater detail
and comprises a transmit/receive (T/R) switch 20 to which the antenna 8 is connected,
a receiver (Rx) 21, a central processor unit (CPU) 22, a memory 23, a short range
transmitter (Tx) 24 and input/output (I/O) driver 25 to which the lock mechanism 16
and the microswitch 12 are connected.
[0022] The programmable door lock 2 of Figures 2 and 3 operates as follows. Remote programming
of the programmable door lock 2 is achieved by transmitting an appropriately coded
signal from the transmitter/ receiver 6 of Figure 1. This signal is received by the
antenna 8 and applied via T/R switch 20 to receiver 21 in which it is received and
demodulated. The transmitted code is decoded by CPU 22 and stored in memory 23.
[0023] When a guest requires access to his hotel room, he operates the door handle 10 of
the programmable door lock 2 and this causes the microswitch 12 to be closed. The
closing of the microswitch 12 is detected by the CPU 22 via I/O driver 25, and is
used to generate an interrogation signal which is transmitted by transmitter 24 and
antenna 8 via I/O driver 25 and T/R switch 20.
[0024] Assuming that the hotel guest has with him his electronic key 3, which may be carried
in a pocket or bag or in any other convenient way, the interrogation signal transmitted
by the antenna 8 of the programmable door lock 2 will be received by the electronic
key 3. When the interrogation signal is received by the electronic key 3, it responds
by transmitting a transponding signal which is indicative of its own security code
and this is received by the receiver 21 of Figure 3 via the antenna 8 and T/R switch
20. The received security code is decoded by CPU 22 and if it corresponds to its own
code stored in memory 23 it causes the solenoid 15 of the lock mechanism 16 to be
activated to cause the door catch 17 (Figure 2) to be retracted to release the door
and allow access to the hotel room. If the received security code does not correspond
to the code stored in memory 23, this may be indicative of someone trying to make
a forced or illegal entry and an alarm signal is generated which is transmitted by
the transmitter 24 via the aerial 8 and the T/R switch 20, to the Tx/Rx 6 of the control
unit 1 of Figure 1 where it is used to inform the hotel staff of the illegal entry
attempt.
[0025] In Figure 4 of the drawings there is shown the block schematic diagram of the electronic
key 3 referred to in Figures 1 and 2. When an interrogation signal is received by
the electronic key 3, it is received by an antenna 30 and is fed via a transmit/ receive
(T/R) switch 31 to a receiver 32. The presence of the interrogation signal is detected
by a central processor unit (CPU) 33 and the security code which has been programmed
into the electronic key 3 and which is stored in memory 34 thereof is used, via an
input/output (I/O) driver 35, to generate a transponding signal which is transmitted
by short range transmitter 36 via the transmit/receive (T/R) switch 31 and antenna
30, back to the programmable door lock 2 which initiated the interrogation signal
as has already been described.
[0026] In this way, the electronic key 3 does not need to be inserted in the programmable
door lock and it is only necessary for it to be in the vicinity of the door lock 2
in order that it may be used to open the door lock and allow access to the hotel room.
[0027] It will be appreciated that the security code which is programmed into the programmable
door lock 2 and electronic key 3 may take various forms dependent upon any particular
application, and, in the hotel system described with reference to Figure 1 of the
drawings, may typically comprise a 16 bit "GUEST" code in combination with a 12 bit
"ROOM" code.
[0028] The embodiment of the invention which has been described has been given by way of
example only and various modifications may be made whilst still utilising the basic
principles thereof. For example, instead of using transmitted signals for programming
the programmable door locks 2, they may be programmed, for example, using fixed electrical
or optical links between the locks and a programming console, by using relay optical
signalling techniques, or through the electrical mains wiring using, for example,
frequency shift keying (FSK) techniques.
[0029] It may also be arranged that when the security code of each transponded signal received
by the receiver (Rx) 21 of the access control module 13 of Figure 3, as well as being
compared with the stored code in memory 23, may itself be stored in the memory 23.
In this way the security codes of all of the electronic keys which have attempted
to access a particular door lock, whether legitimately or illegally, may be transmitted
back to the control unit 1 of Figure 1. This may be done at the time the access is
attempted, at predetermined time intervals or as a result of an interrogate signal
transmitted by the control unit 1 to the access control module 13 of Figure 3. This
would enable the hotel to have accurate information on activities taking place in
the hotel. Also, although in the embodiment of the invention which has been described,
the programmable door lock 2 has been fitted to a door, it could equally well be fitted,
for example, to a door frame, and instead of being operated by the door handle it
may be operated in some other way, e.g. by means of a manual switch or a proximity
switch.
[0030] It will also be appreciated that the integrated architecture of the electronic key
allows it to be readily used as what might be called an electronic purse, charge or
credit card. In operation purchases made within the hotel environs may be recorded
within the electronic key 3 and debited from a pre-stored credit level or added to
a running total of transaction charges.
1. A programmable security lock which is remotely programmable with a security code which
controls the opening thereof, said lock comprising an electronic key which is programmable
with a security code which corresponds to the security code of said lock, and means
for remotely interrogating the security code of said electronic key for the purpose
of opening said lock.
2. A lock as claimed in claim 1, in which the electronic key comprises a transponder
arrangement.
3. A lock as claimed in claim 2, comprising means for transmitting an interrogating signal
to said electronic key and means for receiving a transponding signal from said electronic
key, said transponding signal being indicative of the security code of said electronic
key.
4. A lock as claimed in claim 3, comprising memory means for storing the security code
of said lock, processor means for comparing the security code of the received transponding
signal from said electronic key with the security code of said memory means and for
causing a lock mechanism of said lock to be opened when said security codes correspond.
5. A lock as claimed in claim 4, in which said means for receiving a transponding signal
is also effective for receiving a programming signal indicative of the security code
to be programmed into said lock, said processor means being operable in response to
said programming signal for causing the security code thereof to be stored in said
memory.
6. A lock as claimed in claim 4 or claim 5, comprising a remote lock controller including
means for transmitting said programming signal, and means for receiving a signal transmitted
from said lock.
7. A lock as claimed in claim 6, comprising means for transmitting an alarm signal to
said remote lock controller when said security codes do not correspond.
8. A lock as claimed in claim 6, comprising means for transmitting said security code
of a received transponding signal to said remote lock controller.
9. A lock as claimed in claim 8, in which the security code of each received transponding
signal is stored in said memory means, and the security codes stored in said memory
means are transmitted to said remote lock controller.
10. A lock as claimed in claim 9, in which the security codes stored in said memory means
are transmitted to said remote lock controller at predetermined time intervals.
11. A lock as claimed in claim 9, in which said security codes stored in said memory means
are transmitted to said remote lock controller in response to a signal received therefrom.
12. A lock as claimed in any of claims 4 to 11, comprising actuating means for causing
said means for transmitting said interrogating signal to said electronic key to be
operated.
13. A lock as claimed in claim 12, in which said actuating means comprises a door handle.
14. A lock as claimed in any of claims 3 to 13, in which said electronic key comprises
memory means for storing the security code of said key, means for receiving the interrogating
signal from said lock and means for transmitting a transponding signal indicative
of the security code stored in the memory means of said key.
15. An electronic key for use with a programmable security lock as claimed in any preceding
claim.
16. An electronic key as claimed in claim 15, which is adapted to be used as an electronic
data transfer device e.g. for electronic credit, charge card, or data bank purposes.