U.S. patent number 3,866,173 [Application Number 05/402,703] was granted by the patent office on 1975-02-11 for access control system for restricted area.
This patent grant is currently assigned to The Mosler Safe Company. Invention is credited to Martin R. Meyer, Charles J. Moorman, Frederick A. Reuter, Daniel F. Yorke.
United States Patent |
3,866,173 |
Moorman , et al. |
February 11, 1975 |
**Please see images for:
( Certificate of Correction ) ** |
ACCESS CONTROL SYSTEM FOR RESTRICTED AREA
Abstract
An access control system for controlling the entry and exit of
personnel through a door or a gate of a restricted area. A person
seeking to enter the restricted area inserts a personnel
identification card with magnetically encoded data thereon into a
card reader located outside the restricted area. Then, a secret
number is entered on a keyboard. The system performs checks on the
card and keyboard data to determine if the person seeking to enter
the restricted area is authorized to enter this area. If all the
checks are passed satisfactorily, the door is opened and the person
can enter the restricted area. A written record of each attempt to
enter the restricted area is made by a printer thereby providing a
chronological record of all system events. The system also provides
means for preventing persons in a defined group from entering a
restricted area as well as circuitry to prevent entry by selected
individuals. The system also includes a card erase mechanism which
erases the magnetically recorded card data after a predetermined
number of unsuccessful entry attempts. Since only the magnetically
encoded data is erased, the card may be used by this person for
other purposes as printed and photographic information is usually
included on such cards. The access control system also includes
egress monitoring in the form of a printed record of personnel
egress from the restricted area, the egress monitoring becoming
active when the individual leaves the restricted area and allows
the door to close behind him.
Inventors: |
Moorman; Charles J.
(Cincinnati, OH), Reuter; Frederick A. (Cincinnati, OH),
Yorke; Daniel F. (Brookfield Center, CT), Meyer; Martin
R. (Cincinnati, OH) |
Assignee: |
The Mosler Safe Company
(Hamilton, OH)
|
Family
ID: |
23592994 |
Appl.
No.: |
05/402,703 |
Filed: |
October 2, 1973 |
Current U.S.
Class: |
340/5.54;
340/5.6; 340/5.7 |
Current CPC
Class: |
G07C
9/27 (20200101); G07C 9/23 (20200101) |
Current International
Class: |
G07C
9/00 (20060101); G06k 003/00 () |
Field of
Search: |
;340/149R,149A,274
;317/134 ;70/278 ;235/61.7B |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Pitts; Harold I.
Attorney, Agent or Firm: Wood, Herron & Evans
Claims
What is claimed is:
1. An access control system for controlling movement into and out
of a restricted area through a door by personnel having an
identification card; the system comprising, in combination;
a remotely controllable door lock mechanism for selectively
permitting the door to the restricted area to be opened in response
to door unlock signals, said door lock mechanism being normally
locked,
a personnel detector within the restricted area to detect a person
within said restricted area adjacent said door and in response
thereto to generate a personnel signal,
a door sensor for producing a door open signal when the door to the
restricted area is open;
an egress detector responsive to the occurrence of said door open
signal and personnel signal to produce an egress signal;
a personnel identification card reader located outside the
restricted area for reading card data from a personnel
identification number;
a central control responsive to said egress signal to provide a
read signal to said card reader;
a recorder;
said central control including means operative to receive the
personnel identification number from said card reader and to
actuate said recorder to record that an egress has occurred and the
personnel identification number from the card read by said card
reader; and
said central control including further means operative to produce a
door unlock signal to unlock said door in response to specified
conditions including reading of a card inserted in said reader by a
person outside said restricted area seeking entry who inserts a
personnel identification card in said reader when the door is
locked.
2. The access control system of claim 1 additionally including:
means associated with said card reader for producing a card absence
signal when no card is in said reader,
means for producing a humanly perceptible signal in response to
coincidence of a said card absence signal and said egress signal,
said humanly perceptible signal reminding personnel leaving the
restricted area to insert their personnel identification card into
said card reader.
3. The access control system of claim 2 wherein:
said central control is operative after a predetermined period of
time to turn off said egress signal causing said humanly
perceptible signal to be generated only for a predetermined time
period in the absence of card insertion.
4. The access control system of claim 3 wherein:
said central control includes means to actuate said recorder to
indicate that an egress has occurred and that no personnel
identification card had been read upon expiration of said
predetermined time period without card insertion.
5. The access control system of claim 1 additionally including:
a keyboard located near said card reader outside the restricted
area, said keyboard being provided for entering, by personnel
seeking to enter the restricted area, a secret number which
corresponds to the personnel identification number on their
personnel identification card;
said central control being responsive to entry of said secret
number on said keyboard to transfer said keyboard entered number to
said central control and also to read the personnel identification
card in said card reader;
said central control including a verification circuit to verify
that the secret number corresponds to the personnel identification
number read from the personnel identification card, said central
control producing a door unlock signal if said verification circuit
determines that the secret number and the personnel identification
number properly correspond to each other.
6. The access control system of claim 5 wherein:
said central control is operative to activate said recorder when
the secret number and personnel identification number correspond to
indicate that a normal entry has occurred and also to record the
personnel identification number from the card read by said card
reader, thereby providing an access control system with a means for
providing a record of all movement of personnel through a doorway
of a restricted area.
7. The access control system of claim 5 wherein:
said central control includes a blocking circuit responsive to said
read personnel identification number for determining if said read
personnel identification number corresponds to a person who has
been blocked from entering the restricted area, said blocking
circuit including recorded manifestations of blocked personnel for
producing a block signal if said read personnel identification
number corresponds to a person blocked, said blocking signal being
operative to inhibit generation of said door unlock signal to
prevent unlocking said door lock mechanism.
8. The access control system of claim 7 wherein:
said blocking circuit includes a plurality of interrupted
connections, each associated with one personnel identification
number, each interrupted connection being selectively rendered
continuous by a connector means, said blocking signal being
generated when the personnel identification number of the card read
by said card reader corresponds identically to an interrupted
connection rendered continuous by a connector means.
9. The access control system of claim 7 wherein:
said blocking circuit includes a group block circuit for blocking
groups of personnel from entering the restricted area, said group
blocking circuit responding to selected portions of said read
personnel identification number to produce said block signal when
the selected portions of said personnel identification number
corresponds to a group who have been blocked.
10. The access control system of claim 9 wherein:
said blocking circuit includes a plurality of interrupted
connections, each associated with one personnel identification
number, each interrupted connection being selectively rendered
continuous by a connector means, said blocking signal being
generated when the personnel identification number of the card read
by said card reader corresponds identically to an interrupted
connection rendered continuous by a connector means.
11. The access control system of claim 5 wherein:
said blocking circuit includes a group block circuit for blocking
groups of personnel from entering the restricted area, said group
blocking circuit responding to selected portions of said read
personnel identification number to produce said block signal when
the selected portions of said personnel identification number
corresponds to a group who have been blocked.
12. The access control system of claim 11 wherein:
said blocking circuit includes a plurality of interrupted
connections, each associated with one personnel identification
number, each interrupted connection being selectively rendered
continuous by a connector means, said blocking signal being
generated when the personnel identification number of the card read
by said card reader corresponds identically to an interrupted
connection rendered continuous by a connector means.
13. The access control system of claim 5 wherein:
said card includes access area data recorded thereon, said access
area data being correlated to restricted areas to which personnel
can be selectively admitted;
an indicator means having at least two output signals correlated to
at least two different time periods;
said central control includes an access area control circuit
responsive to said access area data and said indicator means, said
access area control circuit being operative to inhibit generation
of said unlock signal to prevent unlocking of said door lock
mechanism if the access area data read the personnel identification
card does not include data indicating that the individual is
permitted to enter the restricted area to which entry is sought at
the time of day indicated by said indicator means.
14. The access control system of claim 5 additionally
including:
an entry attempt counter responsive to reading of said keyboard
entered data, said entry attempt counter being incremented each
time said keyboard receives a complete secret number entered
therein, said entry attempt counter producing an erase card signal
when said counter reaches a predetermined value, said erase signal
being input to said card reader, said card reader including
circuitry responsive to said erase signal to erase the card data on
the card inserted therein, thereby preventing further use of the
personnel identification card to enter the restricted area, said
counter being reset without production of said erase signal in
response to said unlock signal.
15. The access control system of claim 1 wherein:
said card data of each said personnel identification card includes
a multi-digit number in machine readable form coded thereon, said
number including a multi-digit personnel identification number;
and
said central control further responsive to said card reader for
receiving the personnel identification number read by said card
reader, said central control including a settable decoder
responsive to selected digits of the read personnel identification
number, said decoder producing a block signal when the selected
digits of the read personnel identification number corresponds
identically to the preset setting for said decoder, said block
signal being operative to prevent the generation of unlock signals,
thereby preventing an individual who belongs to a group of
individuals blocked from entering the restricted area from entering
the restricted area.
16. The access control system of claim 1 wherein:
said card data of each said personnel identification card includes
a multi-digit number in machine readable form coded thereon, said
number including a multi-digit personnel identification number;
and
said central control further responsive to said card reader for
receiving the personnel identification number read by said card
reader, said central control including a settable decoder
responsive to selected digits of the read personnel identification
number, said decoder producing a block signal when the selected
digits of the read personnel identification number corresponds
identically to the preset setting for said decoder, said block
signal being operative to prevent the generation of unlock signals,
thereby preventing an individual who belongs to a group of
individuals blocked from entering the restricted area from entering
the restricted area.
17. The access control system of claim 16 wherein:
said blocking circuit includes a group block circuit for blocking
groups of personnel from entering the restricted area, said group
blocking circuit responding to selected portions of said read
personnel identification number to produce said block signal when
the selected portions of said personnel identification number
corresponds to a group who have been blocked.
Description
BACKGROUND OF THE INVENTION
This invention relates generally to the field of access control
system for assuring that only authorized personnel are permitted to
enter or leave restricted areas and particularly to systems
including expensive egress control, group blocking, erasure but not
destruction of cards after a predetermined number of unsuccessful
entry attempts and also a system which includes area access
authorization information which is coded in machine readable form
on the individual's personnel identification card.
Access control systems have been proposed heretofore which utilize
personnel identification cards to control movement of personnel
through doorways. One typical system has utilized personnel
identification cards in connection with a verification check to
determine whether the person possessing the card is a person who
has been authorized to use the card. The verification check
typically requires the person possessing the personnel
identification card to insert the card into a card reader which
then reads the machine readable data encoded thereon and stores
this data at a central control location. The person seeking entry
is also required to enter a secret identification number on a
keyboard located near the card reader. This secret identification
number is then utilized by a verification circuit to determine
whether the person possessing the card also knows the proper secret
identification number which corresponds to that card. If the secret
number is correct, the system assumes that the person possessing
the card is authorized to enter.
In other prior art systems, checks other than verification checks
have been proposed. One such check has been to determine whether a
person's authorization to enter a restricted area has been
withdrawn. Typically such proposals include a computerlike central
processing unit which compares the personnel identification number
read from the card against a list of identification numbers with
respect to which authorization has been withdrawn. Should a
comparison be found between the number read from the card and one
of the numbers on the list of unauthorized personnel, the apparatus
responds to prevent opening the door to the restricted area despite
the fact that other checks performed by the access control system
such as proper verification, were satisfactory.
A failing of such proposed prior art systems, however, has been the
inordinate cost of blocking feature for preventing entry of
unauthorized card holding personnel. This problem has been
particularly acute where large groups of card holders are to be
blocked. For example, if a strike of union workers is in process
and management desires to prevent all union members from entering
the plant during the strike, separate entries would have to be
provided in the list of unauthorized personnel to correspond to
each union employee whose entry is to be denied. As such, prior art
systems have proved to be extremely unwieldy in providing blocking
of personnel on a group basis, that is, denying access to
restricted areas to groups of employees rather than individual
employees.
Some of the proposed prior art access control systems have extended
their surveillance to include egress monitoring as well as entry
monitoring. Such prior art proposals typically include a card
reader and, in some cases, a keyboard located at each entrance to,
as well as at each exit from, restricted areas. In some such
systems, in order to leave a restricted area, the individual must
insert his personnel identification card into the card reader and
also enter his secret identification number in the same identical
manner as required to enter the restricted area. In other systems,
the person seeking to leave the restricted area need only enter his
personnel identification card into the card reader. In both such
approaches, however, the system requires that a card reader be
located on both sides of the doorway to the restricted area. As
such, the cost of each door installation is greatly increased
because at least two card readers are necessary at each doorway.
Furthermore, for the systems having a keyboard on both sides of the
restricted area doorway, the cost is even higher because two
keyboards as well as two card readers are required at each
doorway.
A further typical capability of proposed prior art access control
systems has been to permit personnel access to different restricted
areas according to individualized access authorization information
maintained at the central location which is addressed with the
individual's identification number read from the card.
Consequently, when a person seeks entry to a restricted area, his
personnel identification number must be read from his
identification card and the acces authorization information for
this individual retrieved from the central storage. After the
access authorization information is retrieved, it must then be
checked to determine whether the individual is seeking to enter a
restricted area to which access has been authorized. Consequently,
access authorization checks in such prior art systems require
relatively complicated computer technology and large scale storage
capability. In fact a computer itself is necessary to perform the
access authorization checking functions. Consequently, such systems
have proved to be complicated in design and very expensive to
install.
In view of the foregoing difficulties with the prior art, it is the
primary objective of this invention to provide an access control
system with multiple checks which is less expensive than prior
access control system.
It is a further objective of this invention to provide an access
control system which controls entry to restricted areas, exit from
restricted areas, and fully documents all events occurring at the
doorways to such restricted areas with a minimum of card
reader/keyboard hardware.
It is a still further objective of this invention to provide an
access control system which permits rapid and inexpensive blocking
of access to restricted areas for all individuals in selected
groups of personnel.
In order to achieve these and other objectives of this invention,
an access control system is provided which includes, at each
lockable door to a restricted area, a door control unit having a
door lock, as well as a single keyboard and a single card reader
both of which are located outside of the restricted area. Each
keyboard, card reader and door lock is connected via a
communication link to a central control which is operative to
control much of the operation of all elements of the door control
unit. When an employee wishes to enter a restricted area, he
inserts his personnel identification card into the card reader and
also enters a secret identification number on a keyboard. The
central control responds to the keyboard data and the card data to
determine whether the door lock should be released. In so doing the
central control performs a verification check to determine whether
the person possessing the card is authorized to use the card. In
addition, the central control determines whether the card in the
reader corresponds to a card issued for the particular system or
plant. Additionally, the central control checks the access data on
the card to determine whether the individual has been authorized to
enter the specific restricted area or gate through which entry is
sought. Assuming that all of the different status checks are passed
satisfactorily, the door lock is released and the individual
permitted to enter the restricted area, whereupon a printer is
actuated to record the identification number, time, door and the
fact that an entry has occurred.
The system does not include a second card reader nor keyboard
located inside the restricted area for controlling egress. The
system does, however, include a floormat sensor inside the door
which detects personnel approaching the door from inside of the
restricted area. The sensor activates a buzzer or other humanly
perceptible signal means located outside the restricted area to
remind the person after leaving the restricted area to insert his
personnel identification card into the card reader located outside
the restricted area. When the restricted area door has closed and
the card inserted into the reader, the buzzer stops and the central
control reads the card data and actuates the printer to record the
identification number, time door and the fact that the person so
identified has left the restricted area.
The system includes two blocking features, that is, the system can
selectively block personnel from entering restricted areas. One
blocking feature permits selective identification of individuals
who possess a proper personnel identification card but who are no
longer authorized to enter the restricted area. The second feature
permits selective identification of groups of individuals
possessing proper personnel identification cards who all are not
currently authorized to enter the restricted area. The selective
identification of blocked individuals is achieved by a decoding
circuit and a matrix board arrangement. Diode pins are inserted in
locations on the matrix board which correspond to blocked
individuals. If a block signal passes through the decoder and also
through the matrix board, the signal indicates the individual is
not authorized to enter the restricted area. The group blocking is
accomplished simply by decoding some but not all of the personnel
identification number digits. Combinations of these digits can be
selected by a switch arrangement so that a block signal will be
generated for all individuals having the selected personnel
identification number digits in common.
In all instances, the access control system of the present
invention provides a printed record for each detected system event.
This record is generated by a recorder which, in the preferred
embodiment, is a printer provided to produce the record of the type
of event which has occurred, the personnel identification number
from the card read by the card reader at the time the event
occurred, the door at which the event occurred, the date, and
time.
The foregoing and other objects, advantages and features of this
invention will become more clear from the following detailed
description of one preferred embodiment of the invention taken in
connection with the drawings which form a part of the original
disclosure.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic system diagram showing the central control,
the switch and the door control unit.
FIG. 2 is a schematic diagram of the Sequence Controller shown in
FIG. 1.
FIG. 3 is a schematic diagram showing the Status Check circuitry in
greater detail.
FIG. 4 is a schematic diagram showing a portion of the blocking
circuitry.
DETAILED DESCRIPTION
Referring now to FIG. 1, the access control system thereshown
includes a door control 1, a switch 2, and a central control 3. In
its preferred form, the system includes more than one door control,
however, FIG. 1 shows only one such door control in order to keep
the drawing relatively simple. Each door control 1 controls a
single door to a restricted area controlled by the overall access
control system. The switch 2 interfaces with all of the door
control units 1 of the system and provides a means for connecting
only one door control unit at a time to the central control 3. The
central control 3 is operative in response to signals from a door
control 1 to activate the system according to a predetermined
sequence which depends on the specific event occurring at the
door.
Each door control 1 includes a card reader 10 and a keyboard 12
which are physically located outside the restricted area but
closely adjacent the controlled door. The card reader 10 comprises,
in the preferred embodiment, a magnetic card reader for reading
magnetically encoded information on a magnetic stripe located on a
typical personnel identification card. Such cards are commonly
found in automatic cash dispensing machines, other access control
systems as well as some credit card verification systems. The
keyboard 12, for the preferred embodiment, comprises a typical data
entry keyboard including eight numbered keys. These keys, when
depressed by personnel seeking entry, produce a coded electrical
signal which is preferably stored in a register located at the
keyboard itself. While the preferred keyboard 12 has seven
different keys, it will be readily recognized by those of skill in
the art that keyboards having more or less keys than those for the
preferred keyboard 12 may also be advantageously utilized in
connection with an access control system of the type herein
described.
Typically, a door control 1 having a card reader 10 and a keyboard
12 is utilized in the following manner to control the entrance of
personnel into a restricted area. Upon approaching a restricted
area controlled by the access control system, an employee or other
authorized person inserts a personnel identification card
previously provided to the individual into the card reader 10. In
the preferred form, each card has a magnetic stripe encoded with a
multi-digit machine readable number. The card may also have a
photograph and other data in printed form to assist in personnel
identification. After inserting the card into the card reader 10,
the individual enters into the keyboard 12 a secret identification
number known only to the authorized card holder. A digit counter 14
is responsive to the keyboard 12 to count the number of digits
entered on the keyboard 12. In the preferred embodiment, when four
digits have been entered and stored at the keyboard 12, the digit
counter 14 provides an output signal which is transmitted over a
communication link, or a connecting wire 16, to the switch 2. The
signal on this connecting wire 16 is an entry ready signal which
indicates to the switch 2 that all actions at the door control 1
required of a person seeking to enter the restricted area have been
completed and no further action can be taken at the door control 1
until the central control 3 performs the status checks to be
described in greater detail later.
The switch 2 is operative to scan the signals on the various
connecting wires which link the switch 2 to the system door control
units 1. The switch 2 determines the priority of these door control
units 1 and then connects only one such door control unit 1 to the
central control 3 at any given time. Assuming, that no other door
control unit 1 has an active signal on a connecting wire 16, the
entry ready signal on the connecting wire 16 will be transmitted by
the switch 2 to the central control 3. The switch 2 is also
operative to connect all the communications lines, to be described
later, between the door control 1 of the door given priority by the
switch 2 to the central control 3.
At the central control 3 the entry ready signal which appears on
the connecting wire 16 will be operative to activate a Sequence
Controller 18. The Sequence Controller 18, which will be described
in greater detail below in connection with FIG. 3, is operative to
produce a sequence of timing signals to control the operations at
the central control 3. In response to the entry ready signal, the
Sequence Controller 18 at the central control 3 will cause the
stored keyboard data and the data from the card to be transmitted
to a data storage element 20 at the central control. The data
storage element 20 preferrably comprises a data storage register
for storing electrical representation of the keyboard data and the
card data. The actual sequence of these two operations is not
critical, however, the Sequence Controller 18 will be operative to
produce a Read Card at Door 1 signal which is transmitted from the
central control 3 through the switch 2 and over the communications
wire 22 to the card reader 10 to cause the card reader to read the
personnel identification information which is recorded in machine
readable form on the personnel identification card inserted into
the card reader. As indicated earlier, for the preferred embodiment
of this invention, the personnel identification card comprises a
card much like those used for automatic cash dispensing apparatus
which includes a magnetic stripe on which personnel identification
information is magnetically recorded. As such, the card reader 10
is preferably a magnetic card reader. The data read in response to
the read signal on the wire 22 is transmitted over the data
communication wires 24 to the switch 2 and then to the data storage
20. The card data thus read is stored in a register in the data
storage 20 so that the central control can use this data to perform
status checks. The storage of the card data in the data storage 20
is operative to produce a Response Signal which is used by the
Sequence Controller 18 in a manner to be described later to cause
another control signal to be developed.
Such a further control signal developed by the Sequence Controller
18 is operative to generate a keyboard read signal on line 26 to
read the keyboard data stored at the keyboard 12. This keyboard
read signal is transmitted from the Sequence Controller 18 through
the switch 2, and over the communication wire 26 to the keyboard
12. In response to the signal on the wire 26, the keyboard 12 is
operative to transmit the keyboard entered data over the data
communication wires 24 through the switch 2 to the data sotrage 20.
Receipt of the keyboard data at the data storage 20 is also
operative to generate a Response Signal which is sent to the
Sequence Controller 18 to cause the Sequence Controller 18 to
actuate another control signal line in a manner to be described
later.
A door lock 28, which is normally in its locked position, is
located at each controlled door. The door lcok 28 is operative to
prevent opening of the controlled door from outside the restricted
area unless the door lock 28 receives a door unlock signal on the
wire 29. The door can be manually opened from inside the restricted
area. When this door unlock signal is present on the wire 29, then
the controlled door can be opened from the outside and persons can
pass freely therethrough for a predetermined period of time.
The central control 3 is generally operative when a person is
seeking to enter a restricted area in the following manner. After
the Sequence Controller 18 has read the keyboard data and the card
data into the data storage 20, this data is utilized by the central
control 3 to determine whether the door lock 28 will be opened to
permit the individual to enter the restricted area. In order to
determine whether such entry will be permitted, the central control
3 must perform a number of checks on the data received from the
keyboard 12 and the card reader 10. The keyboard data, as indicated
above comprises four digits which correspond to a secret number.
The card data stored in the data storage 20, on the other hand,
comprises a personnel identification number, a system number,
access area information and any other data which may be utilized by
the access control system, or, indeed, other related systems. The
personnel identification number included in the card data is a
multi-bit number which is assigned to the individual possessing the
personnel identification card. For the preferred embodiment, the
personnel identification number comprises twelve binary bits of
data which correspond uniquely to the individual possessing the
card. The system number included in the card data comprises several
data bits of information which uniquely identify the access control
system on which the card data for the personnel identification card
in the card reader was generated. The access area data from the
card comprises a number of data bits which, in the preferred
embodiment, is twelve bits for identifying the areas which the
individual is permitted to enter or leave. As will be indicated
later, the twelve bits of access area data are divided in half so
that two different sets of access area information bits are formed
for use by the system with one set of bits being used during
daylight hours and the second set of bits being used during the
night.
The central control 3 performs a verification check to determine
whether the individual who has entered a secret number on the
keyboard 12 has actually entered the proper secret number which
corresponds to the card data read by the card reader 10. This
verification is performed by the verification circuit 30. This
verification circuit 30 is described in greater detail in the
copending patent application entitled "Access Control Apparatus,"
Ser. No. 293,595 which was filed on Sept. 29, 1972, and is herein
incorporated by reference. While one specific preferred embodiment
is described in that copending patent application, it will be
recognized by those of skill in the art that numerous other
verification systems might be utilized in place of the specific
verification circuit 30 described in the above identified copending
application.
The function of the verification circuit 30 is to provide a signal
on its output wire 32 which indicates that the proper secret number
was entered on the keyboard 12 for the specific personnel
identification card which was read by the card reader 10. This
favorable comparison indicated by the verification circuit 30 is
but one of the status checks considered by the status check
circuitry 34. The status check circuitry 34 also determines in a
manner described in greater detail later whether the system number
from the card data read by the card reader 10 corresponds to the
system number of the access control system which read the card. A
proper comparison of these two numbers is necessary to permit the
individual who has attempted to enter a restricted area to actually
enter this area. Furthermore, the status check circuitry 34 is
operative in a manner described later in greater detail to
determine whether the access area data on the personnel
identification card read by the card reader 10 indicates whether
the individual possessing the card is authorized to enter the
restricted area at the particular time entry is sought.
The status check circuitry 34 also makes a determination in a
manner described in greater detail below of whether the individual
is blocked from entering the restricted area. Assuming that all of
the above identified checks have been passed successfully, this
information is transmitted from the status check 34 to the Sequence
Control 18 which then responds to activate the printer 36 as well
as to send a signal to unlock the door. The unlocked door signal is
transmitted from the Sequence Controller 18 through the switch 2
and over the connecting wire 38 which turns on a single shot timer
circuit 40 located at the door control 1. The single shot timer
circuit 40 produces an output signal, which, in the preferred
embodiment, lasts for approximately 20 seconds although the time
can be adjusted to suit user requirements. This output signal is
connected to the wire 29 which comprises, as indicated above, the
door unlock signal operative to unlock the door lock 28 and permit
the individual to open the door controlled by the lock 28 and pass
through the doorway into the restricted area. While the door lock
28 is unlocked, the Sequence Controller 18 is also operative to
activate a recorder 36 which in the preferred embodiment is a
printer. Other types of recorders might be provided to suit user
requirements, however, it is desirable to provide a recorder which
will produce a written record of each system event. In the
preferred embodiment, the recorder 36 is operative to print an
event code which corresponds to the type of event which has occured
at the door control 1. The recorder 36 also prints a number
corresponding to the personnel identification number read from the
card by the card reader 10. An indication of the door at which the
event occurred is also printed. The recorder 36 also prints the
date and the time at which the event occurred. As such, the printer
provides a complete written record of the time, date and the door
at which a given identified individual attempted to enter a
restricted area as well as an indication as to whether that attempt
was successful or not. As will become more clear later, the event
identification indicates whether the identified individual was
entering or leaving the restricted area as well as to indicate,
according to a predetermined priority, whether any status checks
were not passed successfully which thereby prevented entry to the
restricted area.
The above description relates to system operation for successful
entry attempts. The system in FIG. 1, however, responds in a
somewhat different manner if all of the status checks are not
satisfied. Specifically, the Sequence Controller 18 does not
generate the door unlocked signal unless all the checks are
successfully passed. Therefore, an individual is not permitted to
pass through the doorway unless all checks are successfully passed.
If an unsuccessful entry attempt occurs, the individual may then
respond in one of two manners. He may proceed to a different
entrance to the restricted area where a guard or some other person
is stationed who can determine from written information on the card
whether the individual should be allowed to enter the restricted
area. On the other hand, the individual may again attempt to enter
the restricted area by placing his personnel identification card in
the card reader 10 and again enter his secret number on the
keyboard 12. Each such entry of keyboard data is operative to
actuate the central control 3 in the manner described above. Each
keyboard read signal on wire 26 is operative in the manner
described above and also operative to increment an entry attempt
counter 41 which counts the number of attempted entries at the door
which occur prior to the generation of a door unlock signal on the
wire 29. If the entry attempt counter 41 should ever reach a
predetermined selectable value, this indication is applied to the
wire 42 which is connected to the card reader 10. Upon receipt of a
subsequent card read signal on wire 22 while the indication is
present on wire 42, the card reader 10 responds to this condition
by erasing the magnetically encoded data on the personnel
identification card. However, the card is returned to the person
seeking entry to the restricted area. This permits the individual
to use the card for other purposes such as obtaining entry through
an attended entrance point but would prevent further access through
unattended automatically controlled doors.
The entry attempt counter 41, as indicated above, is incremented
each time an attempted entry occurs. The entry attempt counter is
incremented by the read keyboard signal transmitted over the wire
26 from the switch 2 to the door control 1 indicating that keyboard
entered data should be read to the central control 3. Since the
keyboard data is only read on entry attempts, the entry attempt
counter 41 is incremented only when an attempted entry occurs. The
entry attempt counter 41, on the other hand, is reset to a value of
zero whenever the door lock 28 is unlocked thereby indicating that
the proper status checks have occurred in order to permit an
individual to enter the restricted area.
The access control system shown generally in FIG. 1 is also
operative to provide a written record of all persons leaving the
restricted area. The system is operative in the following manner to
provide this record. At each doorway, a personnel sensor, such as a
floormat 46, is provided. This personnel sensor is generally
located just inside the door to the restricted area so that an
individual approaching the door from the inside will be detected
thereby, such as by stepping on the floormat 46. The personnel
sensor provides an electrical signal on the wire 48 which sets a
flip-flop 50. The personnel sensor 46 also starts a 20 second
single shot timer 51 whose output is inverted by an inverter 53 to
produce a logical zero signal at the inverter 53 output. When the
door is opened by the individual leaving the restricted area, a
door switch 52 produces a door open signal on the wire 54
indicating that the door is open. This signal is applied to one of
the inputs to an AND gate 56. The other AND gate 56 input is
connected to the output of flip-flop 50. When the door switch 52
produces a door open signal on wire 54 and when flip-flop 50 is
set, the input conditions to the AND gate 56 are at the proper
level to produce an output signal on the wire 58. When this signal
occurs on the wire 58, a second flip-flop 60 becomes set. The
setting of this flip-flop 60 will provide an egress signal on the
output connecting wire 62 which extends between the door control 1
and the switch 2 to indicate to the switch that an egress has
occurred at door 1. This egress signal is used by the Sequence
Controller 18 in a manner to be described later.
The system provides a positive control of personnel when
individuals leave restricted areas. All personnel are instructed to
present their personnel identification card to the card reader 10
when they leave the restricted area. The card reader 10 may be
located some distance from the controlled door so that the door
cannot be held open by the person leaving the restricted area in an
attempt to defeat the system. In the preferred system, however, the
system cannot be so easily defeated because the card reader 10 is
actuated to read a card only after the door has closed behind the
person leaving the restricted area. This control is accomplished
electronically in the following manner.
When a person opens the restricted area door, the flip-flop 60
produces an egress signal at its output. This egress signal is at
the binary "one" state and is applied to one input of an AND gate
61. A second input to the AND gate 61 is at the binary "one" state
when a personnel identification card is detected in the card reader
10. The reader 10 includes a card detector, not shown, for
detecting cards inserted in the reader 10. The card detector may
comprise a switch whose binary output is changed by the presence of
a card in the card reader 10. When a card is not present in the
reader 10, the card detector output signal on wire 59 is a binary
"one." An inverter 63 is connected in series between the wire 59
and the second input to the AND gate 61. Consequently, when the
card detector detects a personnel identification card in the card
reader 10, the second input to the AND gate 61 will be at the
binary "one" state. The third input to the AND gate 61 is at the
binary "one" state when the door is closed as indicated by a binary
"zero" signal on wire 54. An inverter circuit 65 is connected
between the wire 54 and the third input to the AND gate 61 to
produce a binary "one" at the third input to AND gate 61 when the
door is closed. When all three inputs to the AND gate 61 are at
their binary "one" state, the output thereof has a binary "one"
state which is passed through the connected OR gate 67 which
produces at its output a START signal. This START signal is
connected to the switch 2 and then to the Sequence Controller 18 by
the switch 2. The Sequence Controller 18 responds to this START
signal in a manner to be described in greater detail later.
Briefly, however, the Sequence Controller 18 responds to the START
signal to start a predetermined sequence of events to control the
system. When a normal egress occurs, that is when a person leaves
the restricted area, allows the door to close and presents his
personnel identification card to the card reader 10, the system
will read the card and then make a record of the event by actuating
the recorder 36 to produce record of the event which includes the
date, time, door number, personnel identification number and the
event code identifying that an egress occurred. This system
operation will be described in greater detail later.
When a person leaves the restricted area as described above, the
personnel sensor 46 detects the person approaching the door from
inside the restricted area. When the door switch 52 detects that
the door is open, flip-flop 60 will become set. The output of
flip-flop 60 is connected to one input of an AND gate 68. The
second input to the AND gate 68 is connected to the output of an
inverter circuit 53. The AND gate 68 will produce a binary "one"
signal when the input conditions are both at the binary "one"
state. When the flip-flop 60 is set, indicating an egress has
occurred at the door and when the output of the inverter 53 is a
one, which occurs after the single shot timer 51 times out (i.e.
after a 20 second period), a binary "one" signal appears at the
output of the AND gate 68 which passes through the OR gate 67 and
produces a START signal. The Sequence Controller 18 will be started
when the switch 2 connects the door control 1 to the Central
Control 3 and the system will record that an egress occurred,
however, no personnel identification number will be printed because
no card was presented to the card reader 10 by the person leaving
the restricted area before the single shot timer 51 timed out.
In order to remind personnel leaving a restricted area that they
should insert their personnel identification card into the card
reader 10 after leaving the restricted area, a humanly perceptible
reminder signal is generated at a location near the card reader 10
when an egress is detected. The humanly perceptible signal is
generated in response to two different conditions at the door
control 1. The first condition occurs when the flip-flop 60 becomes
set which indicates the personnel sensor 46 has detected an
individual approaching the door from the inside of the restricted
area and the door has been opened. The binary "one" at the output
of the flip-flop 60 is electrically connected to one input of an
AND gate 64. The second input to the AND gate 64 is electrically
connected to the wire 59 which, as indicated earlier, has a binary
"one" signal thereon whenever no personnel identification card has
been inserted into the card reader 10. When both of the inputs to
the AND gate 64 are at their binary "one" state, the output thereof
is operative to actuate a humanly perceptible signal means 66 which
is operative to produce either a visual or audible signal to remind
the individual leaving the restricted area to insert his personnel
identification card into the card reader 10. The humanly
perceptible signal means 66 is preferably in the form of a buzzer
which produces an audible sound although a flashing light or other
visual reminder could be employed.
The humanly perceptible signal generated by the signal means 66
will remain active until one of two events occur. One such event is
the insertion of a personnel identification card into the card
reader 10 which causes the signal on the wire 59 to change to its
binary "zero" state indicating that a card has been inserted into
the card reader 10. When this condition occurs the AND gate 64 is
no longer operative to actuate the signal means 66. The second
condition which turns off the signal means 66 occurs when the
flip-flop 60 is reset as this condition will cause a binary "zero"
signal on wire 62 which is also operative to turn off the signal
means 66. This latter condition is produced, as will be indicated
in greater detail later, by the receipt at the door control 1 of a
read card signal on the wire 22 which is operative to reset the
flip-flop 60. Consequently, a humanly perceptible signal at the
card reader 10 is generated by the signal means 66 after an egress
is detected at the door control 1 and this signal will remain
activated until either the individual inserts his personnel
identification card into the card reader 10 or a signal is received
at the door control 1 to actuate the card reader 10.
Whenever an egress has occurred at the door to the restricted area
as indicated above, the Sequence Controller 18 will cause the card
reader 10 at the door control 1 to read a personnel identification
card whether one has been inserted into the card reader 10 or not.
The read card signal is generated by the Sequence Controller 18 in
a manner described later and transmitted from the Central Control 3
via the switch 2 to the wire 22 at the door control 1. The read
card signal on wire 22 has a number of functions. In the first
place, it is operative to reset flip-flop 60 and also flip-flop 50.
Additionally, the read card signal is operative to activate the
card reader 10 and cause it to read any card inserted therein.
On a normal egress, the card reader 10 will read a personnel
identification card and the data read therefrom will be transmitted
over the wire 24 through the switch 2 to the Central Control 3 and
stored in the data storage 20. Once this occurs, the Sequence
Controller 18 will actuate the recorder 36 to permanently record
that an egress occurred, the personnel identification number of the
person who left the restricted area, the door number, the time and
the date. If, on the other hand, no card was read by the card
reader 10, even though an egress was detected at the door control
1, the Sequence Controller 18 will also actuate the recorder 36. In
this situation, however, an egress will be indicated, but no
personnel identification number will be printed because there is no
way of knowing, without reading a card, the identity of the
individual who left the restricted area.
The access control system of the present invention may, in addition
to the above type of checks, include a separate alarm system for
monitoring various alarm conditions throughout the system. For
example, a separate alarm may be provided to indicate that a door
is open at a time when the door should be closed and locked. This
separate alarm condition is provided at the output wire 72 of an
AND gate 70. The signal on wire 72 may be operative to actuate a
bell, buzzer, light or any other alarm either at the door itself or
at some remote location. This alarm condition is generated when
three separate conditions occur simultaneously at the input to the
AND gate 70. Firstly, the door switch 52 must provide a door open
signal on the wire 54 indicating that the door is open. A second
signal is provided from the output of an OR circuit 75 whose inputs
are inactive only when the output of the single shot timer 40 or 51
is active, i.e. during times when the door is permitted to be open.
As such, the output of the OR circuit 75 will provide a blocking
signal to the input of the AND gate 70 whenever the door is
permitted to be open. The third input to the AND gate 70 is on the
activate separate alarm wire 78 which has a signal having a binary
"one" level when the separate alarm system is actuated.
Consequently, when the door switch 52 indicates that the door is
open, the single shot timer 40 and 51 not running and the separate
alarm circuit is activated as indicated by a signal on wire 78,
each input to the AND gate 70 will be at its binary "one" level and
the AND gate 70 will produce a separate alarm signal on wire 72
that indicates the door is open at a time when it should not be
open. This separate alarm signal will actuate a remotely located
alarm in response to which security personnel can take appropriate
action.
In some instances, and especially when a large number of people are
either entering or leaving the facility, it may be advantageous to
turn off the separate alarm system. This can be accomplished by
placing a binary "zero" signal on the wire 78 to prevent the AND
gate 70 from producing an alarm signal on the wire 72. It will be
recognized by those of skill in the art that the override for the
separate alarm may also be utilized in a similar manner to
deactivate the normal entry and egress controls at each door
protected by the access control system. Consequently, the whole
system can be disabled, if such disabling should be desired, to
permit personnel to pass through protected doorways without
requiring each person to have his personnel identification card
read by the card reader or requiring, on entry to restricted areas,
that the individual enter his secret identification on the
keyboard.
The foregoing description has described the operation and details
of the door control 1. The details of the central control 3 of FIG.
1 are generally well known in the prior art. For exampale, the data
storage 20 comprises two registers, one register for storing the
keyboard data and the second register for storing card data.
Electrical storage registers of the type used in electronic
computers and the like are most advantageously utilized for the
data storage 20. Since such registers are so well known in the
prior art, a more detailed description is not herein provided.
The verification circuit 30 for the preferred embodiment of this
invention is described in the above mentioned copending patent
application and will not be described herein in any greater
detail.
The Sequence Controller 18 in FIG. 1 comprises, in the preferred
embodiment of this invention, a circuit like that shown in FIG. 2.
The circuitry of FIG. 2 includes a free running clock 100 which
produces pulses at the binary "one" state on the clock output wire
101 at a periodic rate determined by the clock frequency which, for
the preferred embodiment, has a frequency of approximately 600 kHz.
The clock output 101 is connected to one of the inputs of an AND
gate 102. So long as a nonactive signal is present on the input
wire 103 to the AND gate 102, the output of the AND gate 102 on
wire 104 will be unchanged and will not be operative to increment a
counter 105 or to trigger a single shot timer 106.
The input wire 103 is connected to the output of the OR gate 107.
Consequently, so long as all of the inputs to the OR gate 107 are
not active, i.e. at their binary "zero" state, the output thereof
connected to wire 103 will remain non-active or at its binary
"zero" state.
When the Sequence Controller 18 is started by the receipt of a
start signal generated in a manner described earlier on the input
line 108 to the OR gate 107, the input line 103 to AND gate 102
will become active i.e. at the binary "one" state. The input on the
line 113 will also become active or at the binary "one" state as
described later in greater detail. Consequently, the first clock
pulse with a binary "one" state received from the clock 100 over
wire 101 will be transmitted through the AND gate 102 to a counter
105 to thereby increment the counter 105.
The counter 105 in the preferred embodiment of this invention
comprises a counter having a single input for receiving and
counting pulses and four output wires for providing a set of binary
signals to thereby permit the counter 105 to provide binary outputs
ranging from a value of 0 to 15. The four binary output wires from
the counter 105 are connected to a decoder 109 which has sixteen
individual output wires, each output wire having a binary "one"
signal thereon when a unique combination of input signals are
applied thereto by the counter 105. As such, the Sequence
Controller shown in FIG. 2 is operative to produce at the output of
the decoder 109 sixteen different control signals for controlling
the sequence of the system operation.
Each pulse on the output wire 104 which increments the counter 105,
is operative to actuate a single shot timer 106. The single shot
timer 106, in the preferred embodiment of this invention, comprises
a timer which produces an active or binary "one" output signal
after a period of twenty seconds has elapsed from the time that an
input pulse was applied thereto. If such an active signal should be
produced by the single shot timer 106, the active signal is
connected to one input to the OR gate 107 to thereby produce an
active signal on the input wire 103. Since the signal on the wire
113 is at its binary "one " state, as will become clear later,
after a twenty second period of waiting with the counter 105 at a
single value, the single shot timer 106 produces at its output a
signal having a binary "one " value which is operative to permit
the next clock pulse from the clock 100 to increment the counter
105. This subsequent clock pulse also restarts the single shot
timer 106. In this manner, the Sequence Controller 18 can never
remain in a condition with the counter 105 permanently set the one
value other than to the value of one.
When the counter 105 reaches a value of zero, the decoder 109 will
produce an output signal having a binary "one" state on the zero
output line 110 which is connected to one input of the AND gate
111. The second input to this AND gate 111 is the inverse of the
start signal. That is, a binary "one" signal is produced at the
second input to the AND gate 111 when the start signal is not
present on the start wire 108. The inverter 112 is operative to
produce the inverse of the start signal at the input at the AND
gate 111 which, in combination with the signal on the decoder
output line 110 is operative to produce an output signal on line
113 to block the passage of clock pulses through the AND gate 102.
Consequently, the counter 105 will remain at a value of zero until
a subsequent start signal is received on the input line 108.
The counter 105 is incremented by the clock when certain
synchronous operations are completed in the proper sequence. For
example, when the decoder 109 produces an output on the line
labeled n, an operation such as reading a card might be initiated.
After the data from the card is read into the data storage within
the central control 3, this card reading operation is completed. A
signal from the data storage 20 to the Sequence Controller 18 over
the line 114 (shown in FIG. 2) would indicate to the Sequence
Control 18 that the card reading operation was complete. This
active or binary "one" signal on the line 114 is applied to one
input of a two input AND gate 115. The second input to this AND
gate 115 is connected to the decoder output line n so that when the
operation complete signal is placed on the input line 114, the AND
gate 115 will provide an active or binary "one" signal to the OR
circuit 107. The OR circuit 107 output will then be at a binary
"one" state and this signal is wired to the input line 103 to the
AND gate 102 to allow the next clock pulse from clock 100 to
increment the counter 105 to the next sequence step. As such, the
counter can be incremented by the proper conclusion of an operation
by the system or by the single shot timer 106, the latter occurring
only when the initiated operation is not completed within the time
period of the single shot timer 106, which is 20 seconds for the
preferred system.
Referring again to FIG. 1, the recorder 36 may comprise any
suitable printing mechanism for recording data in readable form
from various parts of the system. Specifically, the recorder 36
will provide a record of each event and this record preferably
includes an event code which will identify the particular type of
event which has occurred. In addition, the record includes the
personnel identification number, if one is read from a personnel
identification card, to thereby indicate the individual responsible
for the recorded event. The record also includes an indication of
the door at which the event occurred, the data on which the event
occurred and the time at which the event occurred. All of this data
is available from different elements of the central control 3. The
recorder 36 may respond directly to the data, generated in
different parts of the system, however, a print data register (not
shown) is preferably provided for storing this information until
used by the recorder 36.
The central control 3 additionally includes a day/night switch or
indicator 116 which provides a signal to the status check 34 which
is utilized thereby to determine whether the individual is
authorized to enter the restricted area at the time of day at which
entry is attempted. The day/night switch 116 may be manually or
automatically set to indicate whether the day or night access
information contained on an individual's personnel identification
card should be utilized in determining whether entry will be
permitted. This operation will be described in greater detail
below.
The central control 3 of FIG. 1 also includes a clock 117 as well
as a date indicator 118 which are connected to the recorder 36. The
clock 117 provides time signals to the recorder 36 so that the time
of each system event can be recorded. The date indicator 118 also
provides electrical data to the recorder 36 so that the data of
each event is also recorded. The date indicator 118 may comprise a
settable switch arrangement or may actually be a portion of the
clock 117 which is utilized to produce this data indication.
Referring now to FIG. 3, the status check circuitry 34 is shown in
greater detail along with other portions of the central control
which interconnects therewith. As indicated generally above, the
card data and the keyboard data are stored within a storage unit
and, in FIG. 3, the keyboard data is stored in a register 20a and
the card data is stored in a register 20b. The keyboard data is
utilized only by the verification check circuit 30 while the card
data register 20b is utilized for the verification check as well as
for other checks. The verification check itself is described in
greater detail in the above identified copending patent application
and will not be described in any greater detail here.
As indicated above, a printed record is prepared by the recorder 36
and the record includes many different pieces of information. One
such piece of information included in the printed record is a door
number to identify the door at which an event occurred. The print
data register 200 provides a storage location for receiving all the
data which is printed by the recorder 36 after the completion of
each recording operation responsive to system events at one of the
door control units. Digit positions 6 and 7 of the print data
register 200 is reserved for receiving data which indicates the
number of the door control unit at which the event occurred. This
number data is placed into the print data register 200 by a decoder
202 which is activated whenever the Sequence Controller 18 produces
a signal to cause a card reader at a particular door control unit
to read the personnel identification card inserted therein. For
instance, if the card reader at the door control 1 were to be
actuated, the input wire labeled read card at door 1 would be
actuated. This signal is applied to the decoder 202 to produce an
output of 01 which is placed into the digit positions 6 and 7 of
the data register 200. The read card at door 1 signal is also
transmitted to the door control 1 and this signal is always
activated for every controlled operation of the access control
system of this invention, therefore, the proper door number is
automatically placed into the print data register 200 by the
decoder 202 for each recorded event. For convenience, the decoder
202 is drawn with six inputs, however, the preferred system is
operable to control 16 doors. The additional circuitry necessary,
though not shown, is essentially identical to the circuits already
described.
As indicated generally above, a portion of the card data stored in
register 200 and shown schematically as 204 comprises data
corresponding to the system number for the particular access
control system on which the original card data was encoded. Each
attempt to enter a restricted area controlled by the access control
system of this invention requires that the system number of the
card data correspond identically to the system number of the access
control system itself. If the system number for card data and the
machine system number do not correspond, the access control system
is operative to prevent the door from being unlocked and thereby
prevents the individual from entering the restricted area. This
blocking is accomplished through a circuit which includes a set of
switches 206 which are manually settable to the system number
assigned to the access control system. The system number data 204
from the card data register 20b and the switches 206 are connected
to a compare circuit which produces a signal at its output on wire
208 which is active (binary "one" state) whenever the card data
system number does not correspond to the system number as defined
by the setting of the switches 206.
The active signal on wire 208 indicating that the system numbers do
not compare is inverted by an inverter circuit 210 to produce an
input to the AND gate 212 which will prevent the output of the AND
gate 212 from becoming active. As will become more clear later, the
output of the AND gate 212 is active whenever a normal entry occurs
and all checks are successful. Consequently, the binary "zero"
signal from the inverter 210 when the card data system number is
not the same as the system number of the switches 206, is operative
to prevent the indication of a normal entry.
The indication that the system number on the card and the system
number according to the switches 206 are not the same as a binary
"one" signal on wire 208 which is connected to one input of another
AND gate 214. Assuming that the other input to this AND gate 214 is
also active, the output of the AND gate 214 will provide an active
input signal to the fourth input of an event decode circuit 216.
The event decode circuit 216 is preferably a decoder which responds
to a signal at one of eight inputs to produce a decimal code at its
output which is stored in the print register 200 digit position 1.
The code stored in the first digit position of the register 200
corresponds to the event code which identifies the type of system
event which has occurred. While being indicated as a decoder for
converting only eight individual event inputs into an output code,
the decoder 216 may indeed be much larger in size to thereby
identify even more events, should such identification be desirable.
For the circuit shown, however, the event codes are identified
below. some of these events will be described in even more detail
later.
______________________________________ Code Meaning
______________________________________ 0 Normal entry 1 Improper
verification 2 Attempt to enter area not authorized to enter 3
Entry blocked 4 Wrong system number 5 Normal egress 6 Other event 7
Other event ______________________________________
Another check briefly mentioned above which is performed by the
status check circuitry 34 is the check to determine whether the
individual is permitted to enter the particular restricted area
that he seeks to enter. The entry control information, as indicated
above, is stored on the personnel identification card itself and,
for the preferred embodiment, comprises twelve data bits of
information which, after the card is read, is stored in the card
data register 20b as at 220 indicated generally. This information
is divided into two six data bit fields, one field for daytime
access data and the other field for nighttime access data. The
day/night switch 116 is operative to control which six data bits
are utilized at any given time to determine if the individual is
permitted, according to the access control data on the individual's
personnel identification card to enter the restricted area to which
the individual seeks to enter. The day/night switch 116 is
connected via a wire 222 to several AND gates shown generally as
224. When the signal on the wire 222 is active, one of the inputs
to each of these AND gates 224 is active thereby permitting the
possibility that one of these AND circuits may produce at its
output an active signal indicating that the individual is
authorized to pass through the particular door at which he has
sought entry.
When the signal on wire 222 is active, the second six data bits of
the access area data 220 are ignored because the inverter 226
inverts the signal on wire 222 to produce at its output a nonactive
signal which is applied to a group of AND gates shown generally at
228 which prevent each such AND gate from producing an active
output signal. These AND gates 228 are connected, as indicated, to
the last six data bits of the access area data 220. As such, the
day/night switch 116 is operative to consider either the first or
second half of the access area data 220 at any one time.
Each of the AND gates 224 or 228 comprises a three input AND gate
which produces an active signal at its output only when all three
inputs are active. One input to each AND gate, as indicated above,
comprises a signal representing whether it is day or night as
controlled by the day/night switch 116. A second input is connected
directly to one unique location in the access area data 220 stored
in register 20b. The third input to each of these AND gate 224 of
228 corresponds to a signal from one particular door control unit
so that only one such AND gate 224 or 228 can possibly produce an
active output signal at any one time. Consequently, if an
individual is seeking to enter at door number 1, an active signal
will be produced on the wire 230 indicating this fact. Assuming the
signal on wire 222 is active, if the wire 232, which connects
between the input of the AND gate 234 and one data bit position of
the access area data 220 is also active, all of the conditions at
the input to the AND gate 234 have been met and, therefore, the
output on wire 236 will also be active. This active signal is
transmitted through the OR gate 238 to provide an active signal
which is applied to one input of the AND gate 212. As such,
whenever the output of the OR gate 238 is active, this condition
indicates that the individual seeking to enter the restricted area
is authorized to enter the restricted area according to the data
included on his personnel identification card.
Referring again to FIG. 3, blocking circuitry is provided to
determine if an individual should or should not be permitted access
to the restricted area controlled by the system. The blocking
circuitry utilizes the personnel identification number 240 which
comprises part of the card data which is stored in the card data
register 20b. In the preferred embodiment of this invention, the
identification number data 240 comprises twelve data bits of
information which correspond to the personnel identification number
assigned to the individual given a particular card. The high order
data bits of the identification number are transmitted over wires
241 and the low order data bits of the identification number are
transmitted over the wires 242 to form the address to a matrix 243.
If the address to the matrix 243 on the wires 241 and 242
correspond identically to an identification number that has been
blocked, that is, that the individual holding the card has been
prohibited from entering any door controlled by the system, an
active signal is produced at the output of the matrix 243 on the
wire 244. This active signal on the wire 244 is transmitted through
the inverter 245 to one of the four inputs to the AND gate 212.
This active signal on the wire 244 is operative to prevent the AND
gate 212 from producing an active signal at its output thus
preventing unlocking of the restricted area door. The active signal
on the wire 244 is also operative to produce an active output
signal to the AND gate 246 provided the output of the OR gate 247
is also active. This latter condition will be true if the signal on
wire 208 indicates that the system number of the card data is
identical to the switch setting for switches 206 and that the
signals on the wires labeled "other event" are not active. When the
output of AND gate 246 is active, it will cause the event decoder
216 to produce an output signal having a decimal value of 3 for the
event code which is stored in digit position 1 of the print data
register 200. Whenever the event decoder 216 produces an event code
of 3, it means that the individual who sought entry to a restricted
area has been blocked from entering.
In operation of the system, an individual may be blocked from
entering for any number of reasons. One such reason is that the
individual is no longer employed by the corporation having its
doors protected by the access control system. Under these
circumstances, should the personnel identification card remain in
the possession of the individual, it is desirable to prevent such a
former employee from entering the building. Also, as noted above,
it may be useful to block groups of individuals from entering
restricted areas. Such group blocking might be utilized under
circumstances where union employees are on strike and the employer
desires to prevent such union employees from entering the
restricted areas while they are on strike.
To achieve this group blocking feature, the high order bits of the
identification number 240 which are transmitted over the wires 241
are also sent to a decoder 250. This decoder 250 is settable and if
the setting of the decoder 250 corresponds to the high order data
bits of the identification number 240, an active signal is produced
at the output 251 which will have the same effect as the active
output from the matrix 243. As such, whenever the high order data
bits of the personnel identification number 240 correspond to the
setting of the decoder 250, the individual seeking entry into the
restricted area belongs to a group of individuals who have been
blocked from entering this restricted area and entry is
prevented.
The circuitry for providing these blocking features is shown in
greater detail in FIG. 4. The high order data bits of the
identification number are indicated by the four lines labeled ID0,
ID1, ID2, and ID3. These four high order data bit lines are
connected to the input of a decoder circuit 252 which will produce
an active signal at one of sixteen output lines.
Each output line from the decoder 252 is connected to another
decoder and is operative to activate the connected second decoder.
By way of example, the output from decoder 252 labeled 15 which
becomes active whenever the binary value for the four high order
data bits of the personnel identification number are all one, is
connected to one input of decoder 253 and 260 to thereby activate
then decoders 253 and 160 to decode the remaining data bits of the
personnel identification number. The decoder 253 operates in the
same manner as decoder 252 and produces at its output one active
line out of sixteen which corresponds to the binary value for the
four data bits ID4-ID7.
Each output of the decoder 252 is also connected to a unique block
group switch which is selectively utilized to pass the active
signal from the decoder 252 to the output of the decode circuitry
to thereby produce a block entry signal for any individual whose
identification number contains a specific high order bit
combination. By way of example, the 15 output of decoder 252 is
connected to a block group switch 254. Whenever the output 15 of
the decoder 252 is active and whenever the block group switch 254
is closed, an active signal from the decoder 252 on the 15 output
will be transmitted to the input of an OR gate 255 to thereby
produce an active signal at the output thereof which is labeled
block entry. This block entry signal corresponds to the active
signal described in connection with wire 244 shown in FIG. 3 and is
operative, for the example selected, to prevent any person with a
personnel identification number with ones in the first four bit
positions thereof from entering the restricted area.
Other block group switches are provided and these are connected to
other outputs of the decoder 252 to thereby permit decoding of any
one of the sixteen outputs of the decoder 252 to block entry to a
restricted area of individuals having selected high order bit
combinations in their personnel identification number. It will be
recognized by those skilled in the art that the group blocking
switches, such as switch 254, may be operative in response to
decoding of any other group of data bits in a personnel
identification number and need not be restricted to decoding
sequential or only the high order bit positions.
In addition to the group blocking circuitry shown in FIG. 4,
selective blocking circuitry is also shown to selectively block
individuals from entering restricted areas. This circuitry allows
selected individuals to be excluded from entering the restricted
area. To achieve this objective, the output of the decoder 252 as
indicated above, produces an active signal on one of sixteen
different wires which are each connected to a second decoder like
decoder 253 which each have four input wires connected to bits
ID4-ID7 of the personnel identification number. Each such decoder
253 has sixteen output terminals each of which is connected to one
horizontal wire on a matrix board 256. As such, when a signal
appears on one of the horizontal wires of the matrix 256, the first
eight data bits of the personnel identification number have been
decoded.
As shown in FIG. 4, the matrix board 256 has sixteen horizontal
wires as well as 16 vertical wires. There is no actual intersection
between these wires, however, a connecting pin such as a diode pin
can be inserted at the intersection point between any of the
horizontal wires with any of the vertical wires. As a consequence,
an active signal may be transmitted from any horizontal wire to any
vertical wire if a diode pin is inserted at the intersection. When
an individual is blocked from entering the restricted area, the
system owner merely has to locate on one of sixteen matrix boards
like that for matrix 256 and inset a pin in the hole which
corresponds to the identification number of the individual who is
blocked. For example, a diode pin might be inserted at a point
shown generally at 257. This would correspond to an individual who
has an identification number represented in binary as follows:
1111000010. As such, if the diode pin 257 were inserted in the
matrix board 256 and if the decoder 253 produced an output on the
zero output wire, an active signal would be transmitted from the
zero output wire through the diode 257 to the vertical wire labeled
2 for the matrix board 256. It should also be noted that more than
one of the sixteen intersection points on each horizontal wire may
have a diode pin inserted therein. For example, a diode pin 258
might be inserted as shown and this would correspond to an
individual having a personnel identification number:
11110001111.
Each of the vertical wires in the matrix board 256 is connected to
a unique AND gate shown generally at 259. Each of these AND gates
have a second input which is connected to a unique output of a
decoder circuit 260 which decodes the low order personnel
identification number data bits ID8, ID9, ID10, and ID11. If any
one of the AND gates 259 have two active input wires, an active
signal is produced at its output to thereby cause an active signal
to be produced at the output of the OR gate 255 to thereby block
entry to the restricted area for the individual seeking to enter
this area. Consequently, should one of the vertical wires from a
matrix board 256 be active and the corresponding output of the
decoder 260 connected to the same AND gate 259 also be active, the
individual will be blocked from entering the restricted area
because an active signal will appear at the output of the OR gate
255 which is operative in a manner described above to block entry
to the restricted area.
Returning again to FIG. 3, circuitry is provided within the dotted
line 270 to provide for the event decoder 216 in the event that
more than one condition is present which should block entry of the
individual to the restricted area. For example, the individual
might be seeking to enter the restricted area with a card for
another system and the individual also might fail to insert the
proper secret number corresponding to his personnel identification
number. As such, a wrong system number indication would appear on
the wire 208 and also a no verification indication would be placed
on the wire 32. Assuming that the output of the OR gate 271 is
active, the AND gate 214 will produce an active signal at its
output. At the same time, however, an active signal is applied to
the wire 272 which is one of the inputs to the AND gate 273. In
order to prevent a second input from being applied to the input of
the event decoder 216, the signal on the input wire 274 of the AND
gate 273 must not be made active. This, in fact, occurs because the
active signal on the wire 208 is inverted by an inverter circuit
275 to produce a nonactive signal at its output. This nonactive
signal is applied to the input of the OR gate 276. This will
produce a nonactive signal at the output of the OR gate 276 on a
wire 274 connected to one input to an AND gate 273 thereby
preventing an active signal from appearing at the output of the AND
gate 273.
Other similar circuitry is provided within the dotted line 270 to
provide a priority for the specific event which may be decoded by
the event decoder 216 should more than one event occur. According
to the priority scheme established by this circuitry, the event
decoder 216 is operative to produce signals representing events
having a coding in the order ranging from 7 to 0 with the higher
decimal values of the event code having priority over lower decimal
values for the event code.
In the event that all of the tests performed by the status check
circuitry are passed successfully, the AND gate 212 will produce an
active signal at its output 280 which forms the zero input to the
event decoder 216. Since no other event can occur simultaneously
with an active signal on the wire 280, this wire is connected
directly to the zero input of the event decoder 216 to thereby
produce a zero event code to indicate that a normal entry has
occured at a door. This signal is also utilized as an input to one
of the AND gates shown generally at 281. This signal in combination
with one of the Entry Ready signals is operative to produce an
active signal at the output of one of these AND gates 281. These
output signals are connected directly to the door control unit at
the door corresponding to the location where entry is being sought.
This signal comprises an unlock door signal which is operative to
unlock the door at the door control to thereby permit the
individual to enter the restricted area.
In the situation where a normal egress has occured, the normal
egress wire in FIG. 3 will be actuated by the receipt at the status
check 34 of an indication that an egress at any door has occured.
Such a signal is generated for door 1, for example, at the wire 62
shown in FIG. 1. This egress signal comprises one input to an AND
gate 277. The second input to this AND gate 277 is active whenever
the system generates a read card signal to read the personnel
identification card at the door control. When both of the inputs to
the AND gate 277 are active, the output thereof will be active.
This active output signal from the AND gate 277 is connected by a
wire 278 to the five input of the event decoder circuit 216 which
produces a 5 at its output for insertion into digit position 1 of
the data register 200.
While the foregoing description of the invention has been made with
particular emphasis on a preferred embodiment therefor, numerous
modifications may be made to this system without departing from the
spirit and scope of the invention. For example, in order to
simplify the system description, the system has been described as
having six different doors. The preferred system has, however,
sixteen doors. It will be recognized by those of skill in the art
that many more doors may be utilized by this system, however,
additional circuitry must be provided and this additional circuitry
would be connected in parallel with existing circuits to thereby
produce identical operations at additional doors.
In addition to adding more doors to the system, it is possible to
add additional status checks to the system should such additional
checks be desirable. Indeed, circuitry is provided for handling two
additional other events in the priority circuitry 270 although the
nature of these other events has not been specifically defined.
Further, while the described attempt counter is operative after
seven attempts at entry to erase the personnel identification card,
clearly other settings for the attempt counter might be
selected.
The preferred system described above includes a day/night switch
used in connection with testing the access area data from the
personnel identification card. In an alternative system, the
day/night switch can be replaced by a three position switch so that
the access controller of this invention can be used at facilities
having three work shifts a day. With such an option, additional
access area information may be desirable so the card data field
must be expanded accordingly. A further alternative is to use the
day/night switch as a weekday/weekend switch for controlling access
in one manner on weekdays and in another manner on weekends.
Furthermore, each of the above described alternative approaches may
be combined with another such approach to thereby produce a system
with expanded capability.
These and other modifications in form only may be made readily by
those of skill in the art without departing from the spirit and
scope of this invention as defined by the following claims.
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