Note: Descriptions are shown in the official language in which they were submitted.
CA 02399899 2002-08-28
1041-44
KEY SECURITY SYSTEM
BACKGROUND
1. Field of the Invention
This invention relates generally to the field of
controlling and tracking access to various types of
objects, and, more particularly, to a device which can be
used to control access to keys.
2. Prior Art.
It is known in the prior art that many objects have
irLtrinsic value or have value because they enabl= access to
1~ other valuable objects. For ir_stance, jewelry and coins
have intrinsic value due to the value of their precious
stones or metals, automobiles have intrinsic value due to
their ability to provide transportation, and files of
business information have intrinsic value due to the
30 content of t:ne information contained within the files. Due
to their intrinsic value and the potential for theft or
misuse, jewelry, coins, and files are often kept irl
lockable storage cases or cabinets, while automobiles have
- 2 -
CA 02399899 2002-08-28
,_
i
. , v
their own door, trunk, and ignition locks. Because keys to
the locks enable access to such objects, the keys,
themselves, have value as well. Other objects may be
inherently dangerous or create legal liability because
unauthorized use of such objects can create a safety hazard
for.others. For instance, explosives and many medicines are
inherently dangerous if used or dispensed improperly by
untrained individuals. Also, unauthorized use or copying of
keys to apartments or hotel rooms can~'enable theft of
personal valuables and can create personal safety hazards
to tenants and guests.
Regardless of the source of an object's value, its
dangerous nature, or its potential for creating legal
liability, business owners, landlords, and hotel
propri=tors have sought, over the years, to restrict access
to the above-described objects, and others, by limiting
their access to only those individuals who require access
to the objects in order to perform their job functions.
Typically, access has been restricted by first placing the
objects in a locked container. A limited number of
individuals have keys for the container. Then, control
over the removal and re-insertion of an object stored in
the container has been maintained by employing manual
procedural methods such as issuing keys for the container
- 3 -
CA 02399899 2002-08-28
._
to only select individuals (i.e., usually managers or
supervisors), requiring an employee or maintenance worker
to request that a manager or supervisor provide access to
the container for removal and/or re-insertion of objects
from/to the container, and requiring the employee or worker
to sign for any object removed and/or re-inserted from/to
the container. For example, many automobile dealers place
the keys to vehicles on their lot inside a locked box. When
a potential customer desires to take ~ vehicle on a test
drive, the customer's salesperson requests that a manager
open the box so that the salesperson can remove the keys to
the vehicle from the locked box. Similarly, many apartment
landlords store the keys to tenants' units in a locked
container and require maintenance workers to request use of
1~ a key w~sn it is necessary _ar teem to entsr a tenant's
unit tc perform various maintenance tas'.~cs. Li:~C2WlSe, many
hospitals provide anly nursing supervisors with a key to a
medicir_e cabinet and require other nurses to request that
the supervisor open the cabinet to enable the removal of
medicine for a patient.
Un=ortunately, such manual apparatus and methcds have
met wit~ limited success si:lce they typically rely '.~eavily
on the thoroughness of humans to consistently follow
designated procedures. Also, such systems are often fraught
- 4 -
CA 02399899 2002-08-28
i
with the potential for misuse and abuse due to the
dishonesty of some individuals and the inability of the
systems themselves to detect possible misuse and abuse. For
instance, once a salesperson or maintenance worker gains
access to a key, the salesperson or worker may keep the key
out of the locked container until the next day unless a
manager or landlord reviews a log at the end of the day to
determine which, if any, keys have not been returned to the
locked container. By keeping the key Overnight, a
salesperson or cohort may steal a car (or items from a car)
or a worker may return to an apartment complex during the
night to burglarize a unit and, potentially, cause physical
harm to a tenant. Additionally, when a key is kept aut of
the locked container for a longer period of time than
t5 necessary witrout t:~e knowledge of a manager or landlord,
the chances increase that key may be copied or become lost
by the salesperson or maintenance worker. The limited
success and inherent problems of manual systems suggest the
need for a system which automatically controls access to
and tracks the use of various types of objects.
Several automatic systems for key control and security
have been developed and used in the past. One such system
employed a container for storing objects which were each
attached to a unique assembly identified by a conventional
- S -
CA 02399899 2002-08-28
bar-code symbol printed on a tongue of the assembly. The
container incorporated an enclosure and a drawer which,
after unlocking, could be slidably removed or inserted into
the enclosure, thereby creating relative movement between
the drawer and a bar-code scanner mounted to the enclosure.
When stored in the container, the tongue of each assembly
extended downward through an aperture in a top panel of the
drawer to enable reading of the bar-code for each assembly
by the bar-code scanner whenever the drawer was moved
1o relative to the enclosure. Because the bar-code scanner
required relative movement between the drawer and the
enclosure to function, the barcodes associated with each
object could only be read during the opening or closing of
the drawer. Therefore, the system had no way of detecting
the preser_ce or a:osence of an obj ect unless t'r_e drawer was
opened or closed, for example, by a manager or landlord.
Thus, the system could not accurately track the amount of
time that an object was not present in the container, nor
could it determine who actually had possession of the
object. Also, because the assemblies were not restrained
and were therefore, prone to variable, random movement
relative to the drawer and enclosure, misreads by the bar-
code scanner were a continual problem requiring repeated
openings and closings of the drawer to effect accurate
- 6 -
CA 02399899 2002-08-28
readings of all of the bar-codes on the present assemblies.
Other problems, including dust and dirt present on the bar-
codes, also caused misreads by the bar-code scanner.
Additionally, because the bar-codes were visible on the
assemblies, they could be easily copied by an individual
for the creation of substitute objects designed to "fool"
the system, thereby compromising the security supposedly
provided by the system.
Another system is described in United States Patent
No. 6,075,441. The key security system described in that
patent uses a large number of coded metal disks to uniquely
identify the various keys desired to be tracked. This
system has several different drawbacks, including the need
for direct mechanical connections with the coded metal
disks in order to transmit information concerning the
identity of the disks. This need for a direct mechanical
connection is not desirable, because it is unreliable, and
the constant wear from removing the keys can weaken and
ultimately break the mechanical connectors.
There is a need, therefore, in the industry for a
system which controls access to and tracks the use of
objects of various types which address the shortcomings of
the prior art.
CA 02399899 2002-08-28
i--.
SU1~IARY OF THE INVENTION
The present invention overcomes the limitations of the
prior art by providing a key security system which includes
a housing with at least one drawer mounted within the
housing. The drawer has a divider mounted in a
substantially horizontal orientation within the drawer, and
the divider has formed into it a plurality of openings. A
power supply board is coupled to a bottom surface of the
divider. A plurality of electro-optical transceivers are
mounted within the drawer, as is a control card. The
control card is electrically connected to the electro-
optical transceivers and a computer system. A plurality of
key fobs are adapted to fit within the holes in the
divider, the key fobs further including electro-optical
1~ means for communicating wits t~~e electro-optical
transceivers.
_ g _
CA 02399899 2002-08-28
r-.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a perspective view showing the key
security system of the present invention.
Figure 2 is an exploded perspective view showing the
key security drawer of the present invention.
Figure 3 is a perspective view of the key fob used in
the present invention.
Figure 3b is an end view of the key fob used in the
present invention.
Figure 4 is an exploded perspective view of the key
fob used in the present invention.
Figure 5 is a partially cut-away view showing a key
fob inserted into a divider located within the drawer.
Figure 6 is a cross-sectional view taken along the
1~ line 6-a' in Figure 5.
Figure 7 is a partially cut away view showing an
optically isolated transceiver located within the drawer of
the key security system.
Figure 8 is a rear view of the housing illustrating
the drawer locking mechanism of the key security system.
Figure 9 illustrates an alternative embodiment of the
drawer showing substitute locations for the electro-optical
transceivers and control card.
- 9 -
CA 02399899 2002-08-28
,.
Figure 10 is a functional block diagram of the
elements of the control card used in the present invention.
- 10 -
CA 02399899 2002-08-28
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A novel key security system will be described. In the
following description, for the purposes of explanation,
specific component arrangements and constructions and other
details are set forth in order to provide a more thorough
understanding of the present invention. It will be
apparent to those skilled in the art, however, that the
present invention may be practiced without these specific
details. In other instances, well known manufacturing
methods and structures have not been described in detail so
as not to obscure the present invention unnecessarily.
Referring first to Figure 1, a perspective view of a
key security system 10 according to the present invention
is shown. The overall system 10 includes a housing 12,
which contains the various elements of the sec~,:rity system.
The housing 12 will typically be a cabinet that is of a
size and shape which is sufficient to incorporate the
various elements of the system. Figure 1 illustrates the
housing 12 as a cabinet having three different drawers 14.
In figure 1, one of the drawers is shown in the open
position, and the other two drawers are closed. Fans 17
are included to cool the system.
In the preferred embodiment, the housing also includes
a computer system. Figure 1 illustrates how a computer
- 11 -
CA 02399899 2002-08-28
r-
keyboard 20 and monitor 22 can be mounted on the housing.
Not illustrated in Figure 1 is the central processing unit
(CPU), which may be stored within the housing. The monitor
22, keyboard 20 and CPU are connected by means of
appropriate cables (not illustrated). The computer system
is used to control the overall functions of the key
security system 10 of the present invention.
Figure 1 illustrates the preferred embodiment of trie
housing 12. It will be apparent to those skilled in the
art that the housing I2 may take different forms. For
example the housing may be a cart having wheels (not shown)
so that it is portable and can be moved from place to
place. Alternatively, the housing can be incorporated into
a dedicated enclosure which is located in a permanent, or
t5 semi-permanent location. A larger or smaller number of
drawers 14 can also be incorporated into the housing. In
an alternative embodiment, the computer system is not
located within or on top of the housing, but is instead
located at a remote location. Other alternative
embodiments will be apparent to those of skill in the art.
Referring next to Figure 2, an exploded perspective
view of the drawer 14 of the security system is shown. The
drawer is mounted within the housing 12 on slides (not
shown) which permit the drawer 14 to be easily extended.
- 12 -
CA 02399899 2002-08-28
/-
Other alternative methods can also be used to mount the
drawer 14. The drawer 14 has disposed within it a divider
16 mounted in a horizontal orientation. The divider is
supported within the drawer by means of supports 13.
The divider in the preferred embodiment is attached to
the drawer by hinge 15. The hinge 15 is located at the
rear of the drawer 14 as illustrated. The hinge 15 allows
the divider 16 to be easily opened to permit access to the
components underneath. The divider 16 can be manufactured
from any type of suitable material, such as aluminum or
plastic.
The divider includes a number of openings 30. Each of
these openings is shaped to be able to accommodate a key
fob 40. The structure and operation of the key fob 40 is
best described below in connection with Figures 4 and 5.
in the preferred embodiment, there are a total of 300
openings arranged in a grid pattern. It will be apparent
to those skilled in the art that a larger or smaller number
of openings 30 can be formed into the divider, depending on
the number of key fobs 40 that are desired to be used.
Affixed to the underside of the divider 30 is a power
supply circuit board 19. The power supply circuit board 19
performs the function of supplying power to each of the key
fobs when they are inserted into the openings in the
- 13 -
CA 02399899 2002-08-28
divider. The power supply circuit board 19 also includes a
number of openings 32 which are matched in size and shape
to the openings 30 in the divider 16.
Referring again to Figure 2, other components of the
present invention are shown within the drawer . These
include electro-optical transceivers 25. The electro-
optical transceivers 25 are dispersed throughout the
drawer. (In some instances in this application the
electro-optical transceivers are referred to as ~a
"transceiver" ar "transceivers." It will be understood
that such a designation refers to the electro-optical
transceivers 25, and not some other device or structure.)
Each transceiver 25 includes an infrared LED and an
infrared phototransistor which will allow it to communicate
t5 with the key fobs 40. In the preferred embodiment of the
present invention, the transceivers are located on the
inside surface 27 of the side walls 28 of the drawer 14.
This location was chosen because it was found that the key
fobs 40 communicate best with the transceivers 25 when the
transceivers 25 are mounted on the side walls. It will be
apparent to those skilled in the art that the position of
the transceivers 25 can be changed without departing from
the overall spirit and scope of the present invention. For
example, in an alternative embodiment of the invention, the
- 14 -
CA 02399899 2002-08-28
transceivers are mounted on the bottom surface 29 of the
drawer, as illustrated in Figure 9. The total number of
the transceivers 25 will vary depending on the size of the
drawer 14, the number of key fobs 40, as well as other
factors that will be known to those of skill in the art.
In the preferred embodiment a total of 2 - 6 electro-
optical transceivers 25 are used.
It will be apparent to those of skill in the art that
the present invention is not limited to the use of a drawer
to hold the key fobs, as shown in Figure 1. Instead, the
key fobs 40 can be held in any suitable enclosure. For
example, the drawer 14 can be replaced with a cabinet-style
door (not illustrated). The door would be mounted
vertically, as opposed to horizontally, and appropriate
is holders for the key fobs a0 would be p=ovided. Ail that ij
necessa=y is that a support means be provided for '.~_oldirg
the key robs in a manner which allows them to communicate
with the transceiver 25.
A control card 26 is also a part of the key security
system. The control card 26 is used to route electrical
signals between the computer system (shown in Figure 1) and
the transceivers 25. In the preferred embodiment, the
control card is located on the rear of the drawer 1=!!. This
is best illustrated in Figure 8. It will be apparent to
- 15 -
CA 02399899 2002-08-28
those of skill in the art that the control card can be
placed in other locations with equal effectiveness and
without departing from the overall spirit and scope of the
present invention. For example, the control card can be
located within the drawer 14. The control card could also
be mounted within the computer system (not illustrated)
that is used to control the overall operation of the
present invention.
The control card performs several different functions.
As noted above, one of the functions is to route electrical
signals between the computer system and the transceivers.
The control card also translates signals from the
transceivers into a format that is understandable by the
computer system, and vice-versa. The control card also
1p encodes and compacts signals generated by the transceivers.
This li-.~.-is t:~.e amount o. data that is presented to the
compute- system, and improves execution speed.
Appropriate cabling is located within the drawer and
bet~,veer_ =:~e transceivers, the control card and the computer
system. The drawings do not illustrate the cables between
these components. This is dor_e so that the drawings will
be clear. Those of skill in the art, however, will readily
understa~?d how the cables are arranged, depending on the
- 16 -
CA 02399899 2002-08-28
. /..- fr-_
placement of the transceivers 25, control card 26 and
computer system.
The control card 26 is a part of the preferred
embodiment of the present invention. It has been found
that the present invention operates more efficiently if the
control card is present to control and manage the
electrical signals from the transceivers 25 before they are
communicated to the computer system. It will be apparent
that the control card can be eliminated, and that all of
its functions can be implemented in software in the control
system. Such an arrangement, is possible, although not
preferred.
Referring next to Figure 10, a functional block
diagram showing the primary elements of the control card 26
t5 is shown. The control card 26 is comprised o~ a
microcontroller 61 and an RS-232 interface 62. The
microcontroller 61 and the RS-232 interface 62 are, in the
preferred embodiment, mounted on a circuit board with
appropriate circuitry (not shown) to connect them. The RS-
232 interface 62 is used to communicate with the computer
system. The microcontroller performs various functions,
including converting voltage and current levels of the
signals from the computer system so appropriate levels such
that they can control the various electronic and electrical
- 17 -
CA 02399899 2002-08-28
(-~--,
devices within the key security system. A number of signal
lines 63, are coupled to the microcontroller and are used
to send signals to the different components of the key
security system.
Referring next to Figure 3, a perspective view of the
key fob 40 is shown. The key fob 40 is generally
rectangular, and includes an elongated portion 42. At the
end cf the elongated portion 42 is an attachment point 43
which can be used to attach keys. Opposite the attachment
point 43 is an enclosed housing 44. The enclosure includes
the electronic circuitry (not illustrated in Figure 3)
which is used in the operation of the key fob 40. One or
more light emitting diodes (LEDs) 52 may be present on the
key fob 42 in order to provide signals to a user. Although
the preerred embodiment of the present invention is
intended to be used to track keys, it will be apparent to
those skilled in the art that the present invention can be
used to track other items as well.
Referring next to Figure 3b a view of the bottom
portion of the key fob 40 is shown. In Figure 3b the front
side of the key fob (which is visible in Figure 3) is
facing upwards. As illustrated, the bottom surface of the
key fob includes openings through which electrical
components protrude. In the preferred embodiment, an
- 18 -
CA 02399899 2002-08-28
r~.
1
infrared phototransistor 45 and infrared light emitting
diode (infrared LED) 46 are on the bottom surface of the
key fob 40. The infrared phototransistor is used to detect
signals from the transceivers 25 that are located in the
drawer 14. Similarly, the infrared LED 46 is used to send
signals from the key fob 40 to the transceivers 25. The
key fob also includes electrical contacts 47. The contacts
47 are disposed so that the when the key fob 42 is inserted
into the divider 16, they connect with-contacts mounted on
the circuit board 19. Figure 3b also shows that the key
fob includes a raised protrusion 48 on its back surface.
The protrusion 48 is used to align the key fob when it is
inserted into one of the openings 30 in the divider 15.
Figure 4 is an exploded perspective view showing the
1S elements of the key fob 40. rFigure 4 illustrates that the
key fob 40 has withir_ it a circuit board 49. The circuit
board cortairs the necessary hardware to operate the
optical receiver 45 as well as the infrared LED 46 and the
LEDs 52. Each of these devices is mounted to the circuit
board. A cover 41 is placed over the circuit board 49 ,
and the entire assembly is :geld together by a screw 50.
The design and operation of the circuit board will be
apparent to those of skill in the art, and specific details
will not be discussed here.
- 19 -
CA 02399899 2002-08-28
Figure 5 illustrates a key fob 40 inserted into one of
the openings 30 in the divider 16. As can be seen, the
openings include a notch 31. When the key fob 40 is
inserted into the opening 30, the protrusion 48 (not shown
in Figure 5) on the key fob 40 fits into the notch 31 of
the opening. This assures that the key fob will be aligned
in a desired manner.
Figure 6 is a cross-sectional view showing a key fob
40 inserted into one of the openings 30. This figure best
illustrates the manner in which power is supplied to the
key fobs 40. The divider 16 is of sufficient thickness to
hold the key fob 40 in an upright position. In an
alternative embodiment, the divider may not be a single
unit, but can be made up of thin plates separated by
spacers, dividers or other means. The power supply circuit
board 19 is mounted on the bottom side of the divider 10',
as is discussed above. The circuit board has a series of
contacts 53 on it (only one of which is shown in Figure 6).
The circuit board contacts 53 are arranged so that they
meet with the contacts 47 on the key fob 40. The power
supply contacts 53 are used to provide power to the key
fobs 40 when they are inserted into the drawer.
In an alternative embodiment, the key fobs are powered
by batteries stored ir_ the enclosed housing 44. In this
- 20 -
CA 02399899 2002-08-28
embodiment, the key fobs 40 do not need to be connected to
an external power source in order to operated. With this
alternative embodiment, the power supply circuit board 19
and the contacts 47 on the back surface of the key fob 40
can be eliminated.
The operation of the key security system of the
present invention will now be described by means of a
specific example. In this example, it will be as:~umed that
the key security system is being used.to inventory and keep
Io track of keys (such as automobile or house keys). It will
be apparent to those of skill in the art that the present
invention can be used to track the use of other small
items, such as jewelry.
The operation of the key security system is controlled
through the use of the computer system. To this end, the
computer system will use specialized software which is
designed to accomplish the described actions. It will be
apparent to those of skill in the art that the details of
such software are not necessary to describe herein.
2o As a first step, each of the key fobs 40 is first
assigned a unique serial number. This can be accomplished
in one of a number of different ways. In the preferred
embodiment, the circuit board 49 enclosed in the key fob
has mounted on it a programmable memory chip. The memory
- 21 -
CA 02399899 2002-08-28
can store a number or other identification tag which
uniquely identifies the key fob.
The memory chip is programmed by sending an
appropriate signal through the optical receiver 45 located
on the key fob. The preferred embodiment of the present
invention programs the key fob by utilizing a special
optically-isolated transceiver. This feature is best shown
in Figure 7, wher:.~ one of the transceivers 60 is surrounded
by opaque walls 61. The function of the opaque walls 61 is
to isolate the transceiver 60 from outside infrared signals
and other light sources. When a key fob is inserted into
the opening over this transceiver 60, the key fob can
communicate optically only with the isolated transceiver.
The computer system instructs the isolated transceiver 60
1.i to send a signal to the key fob which causes the memory
chip on the circuit board 49 of the key fob ~0 to be
programmed with the unique identification code. This
process is repeated for each of the key fobs to be
programmed.
The key fob can be programmed using alternative
devices. For example, an external electro-optical device
can be used to provide the key fob with an identification
tag, if desired.
- 22 -
CA 02399899 2002-08-28
/'~
f
In an alternative embodiment the key fob is hard-wired
with a permanent identification code. In this instance, it
is not necessary to assign the key fob a unique identifier
as described above.
S The present invention keeps track of keys that are in
use. Consider first the case in which a user desires to
retrieve a particular key. In this case, a large number of
key fobs may be inserted into the drawers. The task is ~o
identify where the desired key is located.
l0 The user enters a password into the computer system.
The user also identifies the unique identification tag of
the key fob that is desired. Other identification methods
may be employed. For example, the user may be identified
using a fingerprint scanner or voiceprint. It will be
t5 apparent to those skilled in the art that other security
measures can be utilized with equal effectiveness. If the
computer system determines that user is authorized to have
access to the keys, the system will unlock the drawer in
which t'r_2 desirsd key fob is located using the solenoid
20 illustrated in Figure 8.
The computer will then send a signal through the
control card 25 to the electro-optical transceivers 25.
The transceivers interrogate the key fobs 40. The desired
key fob identifies its location by energizing one of the
- 23 -
CA 02399899 2002-08-28
LEDs 52 on the top surface of the key fob. The user can
then retrieve the selected key, and close the drawer.
After the drawer is closed, the computer can poll all
of the key fobs to determine which one or ones were
removed. In this scenario, assume for the sake of example
that the key security system includes a single drawer
containing ten different key fobs. The key fobs are
assigned unique identifier designations. In this example,
the key fobs are assigned numbers 1-1Q~. The computer
system will first generate an inventory command for the key
fob with address number 1. The inventory command and
address are sent through the control card 26 to the
transceivers 25. The transceivers generate an appropriate
infrared signal which interrogates the key fobs in the
d=awer. If the key fob having address number 1 is present
in the drawer, it will generate an acknowledgment signal
and se:~d it back to the transceivers. The acknowledgment
signal will be routzd back to the computer system, which
motes the prasenc~ of the key fob. If the key fob with
address number 1 is not present, then the lack of an
acknowlegment signal will be recorded. This process is
repeated for each of the remaining key fobs with address
numbers 2-I0. In this manner the computer system can
create an inventory of the keys that are present in the
_ 2a _
CA 02399899 2002-08-28
drawer, note any absent keys, and report on any variations
from the expected results. The results of the inventory
can be displayed for easy reference on the monitor 22.
The present invention will allow a wealth of data to
be stored and analyzed regarding the use of the keys being
tracked. For example, the computer system can be
programmed to create a database which includes the identity
of all persons accessing the keys, the date and time on
which the keys were removed and returned, and other
similar information. In this manner, a complete history of
the usage of all of the keys can be maintained and easily
accessed.
The description of the present invention has been made
with respect to specific embodiments and constructions of a
1~ key security system. Ic will be apparent to those skilled
in the a=t that the foregoing description is for
illustrative purposes only, and that various changes and
modifications can be made to the present invention without
departing from tre overall spirit azd scope of the present
invention. The full extent of the present invention is
defined and limited only by the following claims.
- 25 -
