U.S. patent number RE29,846 [Application Number 05/860,424] was granted by the patent office on 1978-11-28 for electronic combination lock and system.
This patent grant is currently assigned to Monitron Industries, Inc.. Invention is credited to Sylvan Cole, Frederick E. Feagin, Leonard J. Genest, Daryle Messner.
United States Patent |
RE29,846 |
Genest , et al. |
November 28, 1978 |
**Please see images for:
( Certificate of Correction ) ** |
Electronic combination lock and system
Abstract
A unitary self-contained electronic combination lock is provided
which includes a dead bolt manually operable from one side and
operable from the other side only in response to insertion of a
data combination card carrying a unique binary code in the form of
selectively positioned metallic spots. Sensors located within the
unit generate a binary 1 or 0 signal in response to the presence or
absence of a metallic spot adjacent each sensor. The lock
combination code is automatically changed to the data card's code
upon insertion of a card having a code combination which includes
part of the lock's code so that the previously issued cards will no
longer operate to unlock the door. In this manner, the authorized
code for each lock unit is automatically and independently changed
to render inoperative all previously issued data cards.
Inventors: |
Genest; Leonard J. (Huntington
Beach, CA), Feagin; Frederick E. (Tustin, CA), Cole;
Sylvan (Los Angeles, CA), Messner; Daryle (Buena Park,
CA) |
Assignee: |
Monitron Industries, Inc.
(Santa Ana, CA)
|
Family
ID: |
23706713 |
Appl.
No.: |
05/860,424 |
Filed: |
December 14, 1977 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
430247 |
Jan 2, 1974 |
03926021 |
Dec 16, 1975 |
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Current U.S.
Class: |
340/5.24;
340/5.6; 70/280; 235/449; 361/172 |
Current CPC
Class: |
G07C
9/00722 (20130101); G06K 19/06187 (20130101); G07C
9/215 (20200101); G06K 7/085 (20130101); G07C
9/00904 (20130101); G07C 9/20 (20200101); Y10T
70/7113 (20150401) |
Current International
Class: |
G06K
19/06 (20060101); G06K 7/08 (20060101); G07C
9/00 (20060101); E05B 049/02 () |
Field of
Search: |
;70/277,278,279,280
;317/134 ;235/61.11,61.12,61.7 ;340/149R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Wolfe; Robert L.
Claims
What is claimed is:
1. An independently operable electronic lock and system having an
alterable combination, said lock being operable in response to
insertion of a correct combination code, comprising:
a lock housing adapted to be secured in a door;
securing means attached to said housing;
alterable memory means within said housing storing combination
information for operating said lock;
means within said housing for receiving and detecting a first
stationary combination code inserted into the lock, comparing said
inserted first combination code with said stored combination
information, and generating a drive signal when a comparison is
favorable;
said receiving and detecting means comprising a plurality of sensor
coils connected to receive the output of an oscillator, each coil
having a ferrous metal core and being connected to produce a first
signal across said coil in the absence of a code entry and a second
signal across said coil in the presence of a code entry and
a tuned circuit connected to produce a first output in response to
the first signal across the respective coil and a second output in
response to the second signal across the respective coil;
said inserted code entries comprising at least one electrically
conductive area positioned adjacent to and within the magnetic
field of at least one of said sensor coils to cause said second
signal to be produced across said at least one coil, said first and
second output signals providing a second combination code
corresponding to said first combination code;
drive means within said housing adapted to operate said securing
means in response to said drive signal;
means within said housing for changing said stored combination
information to said inserted combination when a comparison is
favorable; and,
an energy source connected to supply the power requirements of said
lock and system.
2. An electronic lock and system as defined in claim 1 wherein:
said receiving and detecting means includes a card reader mounting
said sensor coils and a protrusion extending inwardly into the card
reader to prohibit access to the portion of the card reader in the
area of said protrusion; and further comprising:
a combination card adapted to be received by said card reader and
having at least one plane, said card having a notch formed in at
least one side to receive said card reader protrusion, said
electrically conductive area being positioned on said plane to lie
opposite a corresponding sensor coil when said card is positioned
in said card reader so that said notch receives said protrusion.
.Iadd. 3. An independently operable electronic lock and system
having an alterable combination, said lock being operable in
response to a correct combination, comprising:
a lock housing adapted to be secured to a door;
securing means connected to said housing;
alterable memory means within said housing storing combination
information for operating said lock;
means within said housing for receiving and detecting a first
received combination, comparing said first received combination
with said stored combination information, and generating an
activation signal when a comparison is favorable;
said receiving and detecting means comprising a plurality of sensor
coils connected to receive the output of an oscillator, each coil
having a ferrous metal core and being connected to produce a first
signal across said coil in the absence of a received combination
area and a second signal across said coil in the presence of a
received combination area and
a tuned circuit connected to produce a first output in response to
the first signal across the respective coil and a second output in
response to the second signal across the respective coil;
said received combination comprising being represented in a form at
least one magnetically reactive received combination area
positioned adjacent to and within the magnetic field of at least
one of said sensor coils to cause said second signal to be produced
across said at least one coil, said first and second output signals
providing a second combination corresponding to said first
combination;
means within said housing adapted to operate said securing means in
response to said activation signal;
means within said housing for changing said stored combination
information to said received combination when a comparison is
favorable; and,
an energy source connected to supply the power requirements of said
lock and system. .Iaddend..Iadd. 4. An independently operable
electronic lock and system having an alterable combination, said
lock being operable in response to a correct combination,
comprising:
a lock housing adapted to be secured to a door;
securing means connected to said housing;
alterable memory means within said housing storing
combination information for operating said lock;
means within said housing for receiving and detecting a first
received combination, comparing said first received combination
with said stored combination information, and generating an
activation signal when a comparison is favorable;
said receiving and detecting means comprising a plurality of sensor
coils connected to receive the output of an oscillator, each coil
having a ferrous metal core and being connected to produce a first
signal across said coil in the absence of a received combination
area and a second signal across said coil in the presence of a
received combination area and
a tuned circuit connected to produce a first output in response to
the first signal across the respective coil and a second output in
response to the second signal across the respective coil;
said received combination being represented in a form comprising at
least one magnetically reactive received combination area adjacent
to and within the magnetic field of at least one of said sensor
coils to cause said second signal to be produced across said at
least one coil, said first and second output signals providing a
second combination corresponding to said first combination;
means within said housing adapted to operate said securing means in
response to said activation signal;
means within said housing for changing said stored combination
information to said received combination when a comparison is
favorable; and,
an energy source connected to supply the power requirements of said
lock and system. .Iaddend..Iadd. 5. An independently operable
electronic lock and system having an alterable combination, said
lock being operable in response to a correct combination,
comprising:
a lock housing adapted to be secured to a door;
securing means connected to said housing;
alterable memory means within said housing storing combination
information for operating said lock;
means within said housing for receiving and detecting a first
received combination, comparing said first received combination
with said stored combination information, and generating an
activation signal when a comparison is favorable;
said receiving and detecting means comprising a plurality of sensor
coils connected to receive the output of an oscillator, each coil
having a ferrous metal core and being connected to produce a first
signal across said coil in the absence of a received combination
area and a second signal across said coil in the presence of a
received combination area and
a tuned circuit connected to produce a first output in response to
the first signal across the respective coil and a second output in
response to the second signal across the respective coil;
said received combination being represented in a form comprising at
least one magnetically reactive area at least temporarily
positioned adjacent to and within the magnetic field of at least
one of said sensor coils to cause said second signal to be produced
across said at least one coil, said first and second output signals
providing a second combination corresponding to said first
combination;
means within said housing adapted to operate said securing means in
response to said activation signal;
means within said housing for changing said stored combination
information to said received combination when a comparison is
favorable; and,
an energy source connected to supply the power requirements of said
lock
and system. .Iaddend..Iadd. 6. An independently operable electronic
lock and system having an alterable combination, said lock being
operable in response to a correct combination, comprising:
a lock housing adapted to be secured to a door;
securing means connected to said housing;
alterable memory means within said housing storing combination
information for operating said lock;
means within said housing for receiving and detecting a first
received combination, comparing said first received combination
with said stored combination information, and generating an
activation signal when a comparison is favorable;
said receiving and detecting means comprising a plurality of sensor
coils connected to receive the output of an oscillator, each coil
having a ferrous metal core and being connected to produce a first
signal across said coil in the absence of a received combination
area and a second signal across said coil in the presence of a
received combination area and
a tuned circuit connected to produce a first output in response to
the first signal across the respective coil and a second output in
response to the second signal across the respective coil;
said received combination being represented in a form comprising at
least one magnetically reactive received combination area for
causing, by its presence adjacent to and within the magnetic field
of at least one of said sensor coils, said second signal to be
produced across said at least one coil, said first and second
output signals providing a second combination corresponding to said
first combination;
means within said housing adapted to operate said securing means in
response to said activation signal;
means within said housing for changing said stored combination
information to said received combination when a comparison is
favorable; and,
an energy source connected to supply the power requirements of said
lock and system. .Iaddend..Iadd. 7. An independently operable
electronic lock and system having an alterable combination, said
lock being operable in response to a correct combination,
comprising:
a lock housing adapted to be secured to a door;
securing means connected to said housing;
alterable memory means within said housing storing combination
information for operating said lock;
means within said housing for receiving and detecting a first
received combination, comparing said first received combination
with said stored combination information, and generating an
activation signal when a comparison is favorable;
said receiving and detecting means comprising at least one sensor
coil connected to receive the output of an oscillator, said coil
having a ferrous metal core and being connected to produce a first
signal across said coil in the absence of a received combination
area and a second signal across said coil in the presence of a
received combination area and
a tuned circuit connected to produce a first output in response to
the first signal across said coil and a second output in response
to the second signal across said coil;
said received combination being represented in a form comprising at
least one magnetically reactive received combination area adjacent
to and within the magnetic field of said coil to cause said second
signal to be produced across said coil, said second output signal
providing at least part of a second combination corresponding to
said first combination;
means within said housing adapted to operate said securing means in
response to said activation signal;
means within said housing for changing said stored combination
information to said received combination when a comparison is
favorable; and,
an energy source connected to supply the power requirements of said
lock and system. .Iaddend. .Iadd. 8. An independently operable
electronic lock and system having an alterable combination, said
lock being operable in response to a correct combination,
comprising:
a lock housing adapted to be secured to a door;
securing means connected to said housing;
alterable memory means within said housing storing combination
information for operating said lock;
means within said housing for receiving and detecting a first
received combination, comparing said first received combination
with said stored combination information, and generating an
activation signal when a comparison is favorable;
said receiving and detecting means comprising a plurality of sensor
coils connected to receive the output of an oscillator, each coil
having a ferrous metal core and being connected to produce a first
signal across said coil in the absence of received combination area
and a received second signal across said coil in the presence of a
combination area and
a tuned circuit connected to produce a first output corresponding
to the first signal across the respective coil and a second output
corresponding to the second signal across the respective coil;
said received combination being represented in a form comprising at
least one magnetically reactive received combination area adjacent
to and within the magnetic field of at least one of said sensor
coils to cause said second signal to be produced across said at
least one coil, said first and second output signals providing a
second combination corresponding to said first combination;
means within said housing adapted to operate said securing means in
response to said activation signal;
means within said housing for changing said stored combination
information to said received combination when a comparison is
favorable; and,
an energy source connected to supply the power requirements of said
lock and system. .Iaddend..Iadd. 9. An independently operable
electronic lock and system having an alterable combination, said
lock being operable in response to a correct information,
comprising:
a lock housing adapted to be secured to a door;
securing means connected to said housing;
alterable memory means within said housing storing combination
information for operating said lock;
means within said housing for receiving and detecting a first
received combination, comparing said first received combination
with said stored combination information, and generating an
activation signal when a comparison is favorable;
said receiving and detecting means comprising a plurality of sensor
coils connected to receive the output of an oscillator, each coil
having a ferrous metal core and being connected to produce a first
signal across said coil in the absence of a received combination
area and a second signal across said coil in the presence of a
received combination area and
a circuit connected to produce a first output in response to the
first signal across the respective coil and a second output in
response to the second signal across the respective coil;
said received combination being represented in a form comprising at
least one magnetically reactive received combination area adjacent
to and within the magnetic field of at least one of said sensor
coils to cause said second signal to be produced across said at
least one coil, said first and second output signals providing a
second combination corresponding to said first combination;
means within said housing adapted to operate said securing means in
response to said activation signal;
means within said housing for changing said stored combination
information to said received combination when a comparison is
favorable; and,
an energy source connected to supply the power requirements of said
lock and system. .Iaddend..Iadd. 10. An independently operable
electronic lock and system having an alterable combination, said
lock being operable in response to a correct combination,
comprising:
a lock housing adapted to be secured to a door;
securing means connected to said housing;
alterable memory means within said housing storing combination
information for operating said lock;
means within said housing for receiving and detecting a first
received combination, comparing said first received combination
with said stored combination information, and generating an
activation signal when a comparison is favorable;
said receiving and detecting means comprising a plurality of sensor
coils connected to receive the output of an oscillator, each coil
having a ferrous metal core and being connected to produce a first
signal across said coil in the absence of a received combination
area and a second signal across said coil in the presence of a
received combination area and
a circuit connected to produce a first output corresponding to the
first signal across the respective coil and a second output
corresponding to the second signal across the respective coil;
said received combination comprising at least one magnetically
reactive received combination area adjacent to and within the
magnetic field of at least one of said sensor coils to cause said
second signal to be produced across said at least one coil, said
first and second output signals providing a second combination
corresponding to said first combination;
means within said housing adapted to operate said securing means in
response to said activation signal;
means within said housing for changing said stored combination
information to said received combination when a comparison is
favorable; and,
an energy source connected to supply the power requirements of said
lock
and system. .Iaddend..Iadd. 11. An independently operable
electronic lock and system having an alterable combination, said
lock being operable in response to a correct combination,
comprising:
a lock housing adapted to be secured to a door;
securing means connected to said housing;
alterable memory means within said housing storing combination
information for operating said lock;
means within said housing for receiving and detecting a first
received combination, comparing said first received combination
with said stored combination information, and generating an
activation signal when a comparison is favorable;
said receiving and detecting means comprising at least one sensor
coil connected to receive the output of an oscillator, said coil
having a ferrous metal core and being connected to produce a first
signal across said coil in the absence of a received combination
area and a second signal across said coil in the presence of a
received combination area and
a circuit connected to produce a first output corresonding to the
first signal across said coil and a second output corresponding to
the second signal across said coil;
said received combination being represented in a form comprising at
least one magnetically reactive received combination area adjacent
to and within the magnetic field of said coil to cause said second
signal to be produced across said coil, said second output signal
providing at least part of a second combination corresponding to
said first combination;
means within said housing adapted to operate said securing means in
response to said activation signal;
means within said housing for changing said stored combination
information to said received combination when a comparison is
favorable; and,
an energy source connected to supply the power requirements of said
lock
and system. .Iaddend..Iadd. 12. An independently operable
electronic lock and system having an alterable combination, said
lock being operable in response to a correct combination,
comprising:
a lock housing adapted to be secured to a door;
securing means connected to said housing;
alterable memory means within said housing storing combination
information for operating said lock;
at least one sensor coil within said housing connected to receive
the output of an oscillator, said coil having a ferrous metal core
and being connected to produce a first detection signal across said
coil corresponding to lack of proximity to said coil of a
combination area of a first received combination representation and
a second detection signal across said coil corresponding to
proximity to said coil of a combination area of said first received
combination representation;
a circuit connected to produce a first comparison signal
corresponding to the first detection signal across said coil and a
second comparison signal corresponding to the second detection
signal across said coil;
said received combination representation being in a form comprising
at least one magnetically reactive received combination area
causing, by at least the temporary proximity of said area to said
coil within the magnetic field of said coil, said second detection
signal to be produced across said coil, said second comparison
signal providing at least part of a second combination
representation corresponding to said first received combination
representation;
means within said housing for comparing said second combination
representation with said stored combination information and
generating an activation signal when a comparison is favorable;
means within said housing adapted to operate said securing means in
response to said activation signal;
means within said housing for changing said stored combination
information to correspond to said received combination
representation when a comparison is favorable; and,
an energy source connected to supply the power requirements of said
lock and system. .Iaddend.
Description
BACKGROUND OF THE INVENTION
This invention relates to an electronic lock system and, more
particularly, to an electronic switch for use with a data
combination card having a binary code indicator distributed over
the surface thereof and operable to actuate a door lock in response
to the insertion of the data card in the switch system.
This invention has particular application to use in buildings, such
as hotels, having large numbers of rooms required to be locked, and
is intended to replace the conventional mechanical lock and key
system now in general use. However, it will be understood that the
system of this invention could be used with any building or
enclosure requiring a locked door, such as safedeposit boxes or
automobiles.
In typical electronic systems for controlling entrance to protected
areas, a door is provided with an electronic lock which responds to
a preselected binary code or combination contained on a key which
frequently takes the form of a card. A person wishing to gain
entrance through the door inserts his card into a receptacle
associated with the lock and the lock circuitry actuates the bolt
if the card is correctly coded. Such electronic locks have very
significant advantages as compared with conventional lock systems,
such as the very large number of code combinations which are
available on a card of very small size.
The general inflexibility of the mechanical lock and key systems
currently in use prohibits the convenient changing of locks,
combinations or key settings. Therefore, a large number of keys are
normally issued thus presenting a security problem. Some electronic
systems which have attempted to overcome these deficiencies employ
a central control unit electrically connected to each of the many
individual doors to remotely set and change the individual lock
combinations, sense the coding on a card inserted at the various
remote door locations, and initiate the bolt action on the remote
door locks. One apparent disadvantage of such systems is the
susceptibility to failure of all locks if the central control unit
is inoperable. In addition, electrically wiring all individual
locks to the central control unit is expensive and often
inconvenient, especially in older buildings.
In other electronic systems where the central control unit is not
employed, the individual lock combinations on each door must be
individually changed by manually resetting the switches or changing
electrical connections before a new card will operate the lock.
Where this system is employed in a hotel, a large expenditure of
time by authorized personnel is required each day to change lock
combinations for those rooms which are to receive a new
occupant.
In addition, the mechanical latch portion of previous electronic
lock systems typically requires large amounts of energy to actuate
the locks by pulling the bolt back against a spring or the like.
Such systems have been considered necessary in the past since it is
desirable to employ the conventional rotating handle inside the
door to withdraw the bolt without employing a card. The large
energy requirements, however, necessitate inconvenient and
expensive connection to a high energy source. One solution has been
to employ a rotating handle on the outside which will only operate
when a correctly coded card is inserted. This, however, defeats the
dead bolt feature by providing a mechanical linkage through the
outside of the lock which if forceably removed provides a ready
means for manually retracting the bolt. Furthermore, such systems
frequently do not incorporate a dead bolt feature but employ
spring-loaded bolts to allow the bolt to be retracted when the door
is being closed and extended again after the door is closed.
SUMMARY OF THE INVENTION
A method of comparing codes inserted into a combination comparator
with codes previously stored in an active memory and changing the
stored codes in response to a favorable comparison is provided in
which first and second codes stored in the active memory are
compared with third and fourth codes inserted into the combination
comparator. Specifically, the stored second code is compared with
the inserted fourth code and if they are identical a match signal
is generated. If they are not identical, the stored second code and
the inserted third code are compared and if they are identical a
match signal is generated and the active memory is changed to
replace the previously stored first and second codes with the
inserted third and fourth codes respectively.
In one embodiment of the invention, a unitary lock housing is
secured in a notch cut into one edge of a door by clamping the door
surrounding the notch between an adjustable back plate on the
inside of the door and the remainder of the housing. A bolt
slidably mounted in the housing reciprocates either upon actuation
of a motor in response to insertion into the housing from outside
of a correctly coded data combination card or rotation of a door
handle mounted on the housing back plate. A pin through the bolt
rides in a non-linear slot of a cam which rotates within the
housing in response to actuation of either the motor or the door
handle. A detent in the non-linear slot prevents inward pressure
against the bolt from rotating the cam in either direction when the
bolt is fully extended. A spring-loaded catch protruding from the
end of the bolt contacts the door jamb when the door is being
closed and pushes inwardly against the spring force until the lug
engages the bolt receptacle to hold the bolt aligned with the
receptacle until the bolt is extended. All of the mechanical
elements of the lock are contained behind the outside face of the
housing so that the lock's mechanical linkage is not normally
accessible from outside the housing.
In one embodiment of the invention, a data combination card carries
code information to be inserted into the lock. The data card has a
central coded layer secured between two outer layers to form a
composite card. The three layers are composed of electrically
non-conductive, nonmetallic material with the central layer having
a plurality of holes formed therein covered by metal foil on one
side. The card is coded by selectively removing spots of metal
covering certain of the holes.
A data card reader provided within the lock housing includes a
plurality of iron core transformers, each having an alternating
current source connected across the transformer first coil to
produce a first output signal across the second coil. When a data
card is inserted into the card reader, the metal spots in the
central layer adjacent corresponding sensor transformers produce a
second output signal across the respective transformer second coils
to provide a combination code of first and second output signals
corresponding to the information encoded on the data card.
Various switches are provided within the housing to detect the
fully extended and fully retracted positions of the bolt, the bolt
position where only the catch lug is extended, the direction in
which the cam has rotated to retract the bolt, and whether the door
is closed. Various logic components actuate the motor to retract
the bolt when a correctly coded data card is inserted into the card
reader. After a data card is removed, or rotation of the handle is
completed, the various logic components respond to the bolt
position as detected by the various switches to switch on the motor
to extend the bolt so that only the catch lug protrudes beyond the
edge of the door so that the catch will engage the bolt receptacle
when the door is closed. When the door closed condition is
detected, the motor is actuated to extend the bolt completely into
the bolt receptacle. Batteries within the housing supply the power
requirements of the lock and system.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the unitary electronic lock and
system of this invention installed in a door;
FIG. 2 is a cross-sectional elevation view of a preferred
embodiment of the invention taken along the line 2--2 of FIG.
1;
FIG. 3 is a cross-sectional elevation view taken along the line
3--3 of FIG. 2;
FIG. 4 is a perspective exploded view of the bolt structure of
FIGS. 1 and 2;
FIG. 5 is a perspective view of the data combination card employed
in the preferred embodiment of the invention with the top two card
layers partly broken away;
FIG. 6 is an elevation view of the card reader employed in the
preferred embodiment of the invention with the top surface partly
broken away;
FIG. 7 is a cross-sectional view taken along line 7--7 of FIG.
6;
FIG. 8 is a perspective view of one of the sensor elements mounted
in the card reader of FIGS. 6 and 7;
FIG. 9 is a schematic representation of the sensor element of FIG.
8 and associated circuitry employed in the preferred embodiment of
the invention;
FIG. 10 is a schematic block diagram of the electrical elements of
the preferred embodiment of this invention;
FIG. 11 is a flow chart of the logical operations of the code
processor unit and associated memory of FIG. 10; and,
FIG. 12 is a flow chart of the logical operations of the motor
control logic unit and associated motor of FIG. 10.
DESCRIPTION OF THE INVENTION
The particular embodiment of the invention illustrated and
described herein is an electronic lock system for actuating a
switch with a data combination card to open a door lock, such as
might be employed in the door of a hotel or the like. As will be
apparent, however, the principles of the invention are applicable
to diverse applications for switching to open and close locks or
actuate other devices, such as controlling a beam of light.
The complete system shown and described herein may be considered in
five functional sections: the lock, the data combination card, the
card reader, the sensors, and the central processing unit. These
functional sections are described in order herein to assist in
understanding the structure and the interrelated functions of the
various sections.
THE LOCK
FIG. 1 shows the entire electronic lock system of this invention
contained in a unitary housing 20 and installed in the door of room
No. 301. The housing 20 is preferably molded or cast as an integral
shell of sturdy material, such as aluminum, brass or engineering
plastic, which will withstand weathering and also resist attempts
to break through the lock from the outside. All of the necessary
items for operation of this system, except the data card carried by
the room occupant, are contained within housing 20 including the
necessary battery power supply, thus rendering each unit fully
independent and self-contained. The housing has a protruding
section 22 with a slot 24 for receiving data card 120 to be
inserted from the outside. The handle 26 on the outside of the door
does not operate the lock but is provided merely for convenient
pushing or pulling on the door once the lock is open. Thus, there
is no mechanical linkage into the lock from outside the door and
the door may be opened from outside only by inserting a correct
code combination into the lock, such as an appropriating coded data
combination card, pausing momentarily while the necessary
electronic functions are performed and the bolt is retracted, and
then pushing on the handle 26.
The housing and bolt dimensions may be altered to fit practically
any existing door and jamb system. As is shown in FIG. 2, the
housing back plate 28 is not only easily removable to provide
access to the housing interior in order to change batteries 84 or
for other maintenance, but allows the unit to accommodate various
door thicknesses by merely screwing the back plate towards or away
from the remainder of the housing 20. Installation only requires
cutting an appropriate size notch inwardly from the side or edge of
the door, sliding the unit into the notch as shown in FIG. 2, and
securing the housing to the door by screwing the back plate 28 to
the rest of the housing. Additional fastening means (not shown) may
be employed to secure the housing to the door from the inside or
edge of the door. The entire system can be assembled or repaired at
a remote location and tested before shipment so that installation
is accomplished in a matter of minutes. Since each unit is
independent and contains its own energy source, connection to a
high energy source or to a central control system is not
required.
Bolt 42 is shown in its fully retracted position in FIGS. 2 and 3.
The door lock may be operated from inside by manually rotating the
door handle 30 and connecting shaft 32 which extends through the
housing and rides in sleeve 34 against bearing 36. Shaft 32 is
attached, by welding or the like, to bolt cam plate 38 so that
rotation of the handle rotates the cam plate about the longitudinal
axis of shaft 32.
Bolt 42 (FIG. 4), preferably constructed of a block of rigid,
durable material, such as stainless steel or the like, has an upper
short leg 44 and a notched lower leg 46 forming two sides of cam
receiving slot 48. The periphery of cam 38 rides in slot 48 so that
guide pin 50 extending through the two legs 44 and 46 and through
the non-linear cam plate slot 40 (FIGS. 3 and 4) translates the
rotation of cam plate 38 into longitudinal reciprocation of bolt
42. A low friction bearing 52, such as a nylon sleeve, surrounds
guide pin 50 in slot 40 to reduce the friction as between the pin
and the cam 38. The two guides 54 at the end of slotted bolt leg 46
ride on opposite sides of shaft 32 while the opposite end of the
bolt rides within slot 56 extending through the wall of housing 20
to maintain the bolt longitudinally aligned as it reciprocates.
Bolt 42 has a spring-loaded catch to temporarily hold the door shut
upon catching in bolt receptacle 58 when the door is first closed
to allow the bolt an opportunity to fully extend. This catch
mechanism includes a hollow cylinder 60 which rides within
cylindrical aperture 62 in the end of the bolt. Spring 64 within
the cylinder 60 tends to push the catch outwardly but against
restraining U-shaped nylon strip 66 secured over the end of the
bolt pin 68, a rectangular cutout 70 in the connecting leg allows a
projecting wedge-shaped lug 72 to protrude about three-eighths inch
from the end of the bolt through the nylon strip. The strip 66 is
positioned in the recessed opposed faces of the bolt 42 so that its
outer surfaces are slightly raised above the bolt to provide low
friction bearing surfaces between the bolt and the sides of the
slot 56 and bolt recess 58.
When the bolt 42 is fully extended, the cam 38 will be rotated
clockwise 90.degree. from its position shown in FIG. 3 and pin 50
will be positioned at detent 41 one-half way between the two ends
of cam slot 40 which extends slightly more than 180.degree. around
the periphery of the cam. Upon further rotation of the cam in
either direction, pin 50 travels along cam slot 40 and since the
non-linear slot is closer at its ends to the cam center of
rotation, the bolt 42 is withdrawn into the housing 20. The
non-linear construction of slot 40 also serves to minimize starting
torque on the motor when a card is used to retract the bolt and
detent 41 eliminates the possibility of cam rotation by inward
pressure against bolt 42.
After the door is open, the lock mechanism will extend the bolt
until only the lug 72 protrudes beyond the edge of the door, as
will be explained hereinafter. As the door closes, the angled
surface of lug 72 rides against the striker plate 74 attached to
the jamb and the cylinder 60 is pushed back into the bolt against
spring 62. As soon as the lug fully engages the bolt receptacle 58,
the spring pushes the lug into the bolt receptacle thus stopping
the door from bouncing back or being pulled away from the jamb to
provide the bolt 42 an opportunity to fully extend about another
one inch into receptacle 58, as will be explained hereinafter.
Slot 40 extends slightly more than 180.degree. around the periphery
of the cam plate 38 so that the bolt may be retracted by rotating
handle 30 in either direction. The motor 76 has a low inertia and
is internally clutched to allow the cam 38 to be turned by hand
against the drive of the motor without damaging the motor. Since
there is also a straight spur gear drive from the motor 76 to cam
plate 38, there is no impediment to opening the door from the
inside whether the motor is on or off.
To open the door from the outside, a data combination card 120 is
inserted into slot 24 to actuate the electronic mechanism,
explained hereinafter, which switches on electric motor 76 (FIG. 3)
if the card contains the appropriate combination code. Pinion gear
80, mounted on motor drive shaft 78, meshes with the semi-circular
gear 82 extending more than 180.degree. around the periphery of cam
38 to drive bolt 42. The power for motor 76, as well as for the
rest of the circuitry described hereinafter, is provided by
batteries 84 arranged conveniently within the housing 20, such as
along one wall as is shown in FIGS. 2 and 3. Batteries 84 may be
conveniently changed by merely unscrewing back plate 28 and pulling
out the batteries.
Two switch cams 90 and 92 are secured to cam plate 38 with bolts 86
to rotate in conjunction with the cam plate about the same axis of
rotation. Each cam 90 and 92 has a partly recessed periphery 91 and
93 respectively which overlap at 102. A low friction bushing 94,
such as a nylon sleeve, surrounds shaft 32 between switch cam 92
and mounting plate 96 to maintain the shaft in alignment and to
apply sufficient pressure to keep the opposite end of the shaft
riding snugly against bearing 36.
Two microswitches 98 and 100 are positioned so that their roller
bearing switch arms 98A and 100A ride along the periphery of the
cams 90 and 92 respectively (FIG. 3). The microswitch roller
bearings are aligned along a horizontal axis so that they are both
positioned at 102 in their respective recesses when the bolt 42 is
fully extended.
As may be seen in FIG. 3, microswitch 98A rests at one end of cam
recess 91 when the cam 38 is fully rotated in the counterclockwise
direction. Microswitch arm 98A continues to ride in recess 91 as
cam 38 begins to rotate clockwise until bolt 42 is fully extended
and cam 38 centered so that microswitch arm 100A, which has been
riding along the raised periphery of cam 92, drops into the recess
93 at point 102. When both switch arms are in their respective
recesses at 102, the bolt is fully extended. As cam 38 continues to
rotate in the clockwise direction, bolt 42 again retracts and
switch arms 98A will ride up out of recess 91 while switch arm 100A
continues to ride in recess 93. In this manner, microswitches 98
and 100 sense the direction in which cam 38 has been turned as well
as the fully extended position of the bolt.
Two other microswitches 106 and 108 are actuated by the raised
extension of guide pin 50 contacting the respective arms 106A and
108A as it travels with reciprocating bolt 42. When bolt 42 is
fully retracted, as shown in FIG. 3, guide pin 50 engages switch
arm 106A. Microswitch arm 108A is contacted by pin 50 to switch off
motor 76 as the bolt extends to the point where only catch lug 72
extends beyond slot 56 so that the door can be closed against the
spring action of the catch without interference from the rest of
the bolt. When the door is closed and the catch engaged, magnetic
switch 110 inside housing 20 detects the presence of the magnet 112
behind striker plate 74 and switches on motor 76 to continue the
bolt extension into receptacle 58.
In operation, when the appropriate card 120 is inserted into slot
24, motor 76 is switched on to withdraw the bolt 42 from receptacle
58. Guide pin 50 contacts switch arm 106A when the bolt is fully
withdrawn to switch the motor off. The door may then be pushed open
and the card withdrawn. Magnetic switch 110 detects the absence of
magnet 112 when the door is open and switches on motor 76 to extend
the bolt until guide pin 50 contacts switch arm 108A. This switches
off the motor so that only the catch lug 72 extends beyond the edge
of the door to engage the striker plate and the bolt receptacle
when the door is closed. After the door is closed, lug 72 prevents
the door from being pulled or bounced open and magnetic switch 110,
detecting the presence of the magnet 112, switches on motor 76 to
continue the bolt extension until both switch arms 98A and 100A are
riding in their respective recesses at position 102, whereupon the
motor 76 is switched off. The door can be opened again only by
either inserting an appropriate data combination card or by
rotating handle 30 from inside the door.
As previously explained, rotating handle 30 in either direction
withdraws the bolt 42 and overrides the inertia and/or drive of
motor 76 so that the door may be opened from inside. The relative
position of microswitch arms 98A and 100A indicates the direction
in which cam 38 has been turned and magnetic switch 110, detecting
the absence of magnet 112, will switch on the motor 76 to begin
extending the bolt 42. The bolt will continue to extend until the
guide pin 50 contacts switch arm 108A and the procedure will
continue as previously described.
A lock-out slide switch 114 is positioned to be operated from
inside the door to disconnect electrical power from the card reader
132, thereby disabling the lock to prevent entry from outside
through the use of any card. When switch 114 is actuated, its
switch arm 114A is moved against switch arm 106A so that retraction
of bolt 42 by rotating handle 30 causes pin 50 to push against
switch arm 114A, as well as switch arm 106a, thereby resetting
switch 114 to reconnect the electrical power so that the room
occupant cannot lock himself out with switch 114. It will be
apparent from the foregoing that a dead bolt lock is provided
whenever the bolt is engaged in receptacle 58 and that very little
energy is required to extend and retract the bolt since it is not
acting against the force of any springs or the like. In fact, a 6
volt, 40 milliamp motor has been found to operate satisfactorily in
the described embodiment of the invention.
THE DATA COMBINATION CARD
The data combination card employed in this invention may take many
forms, such as raised ferrous or nonferrous metal spots on a
nonmetallic substrate. However, in the preferred form of this
invention, the card 120 shown in FIG. 5 is originally an elongated
rectangular strip, divided into three equal parts to be folded
together from one end so that the end portion first folded finally
becomes the central layer of the card. The card has three layers
laminated together, the two outer layers 122 and 124 and the
central layer 126 being composed of a nonmetallic, electrically
insulating material, such as plastic, cardboard or the like. The
central layer 126 also contains a predetermined matrix pattern of
holes adapted to receive nonferrous metal plugs. However, in this
embodiment of the invention, the nonferrous metal spots 128 are
formed by a sheet of aluminum foil secured to the reverse side of
central layer 126. Before the three layers are laminated together,
some of the metal spots are punched out or removed from across the
holes to create a binary code or combination of holes and metal
spots on the central layer, which combination is sensed to
determine the operation of the door lock. The three layers are then
laminated together so that the code is invisible and attempts to
remove the outer layers will result in the destruction of the card
and its code pattern.
Each card 120 has an elongated notch 130 cut in one side to match a
tab in the card reader so that the card can be inserted into the
card reader in only the one position which correctly positions the
card's pattern of holes and spots in the reader.
A device (not shown) for encoding the data combination cards 120
may include anything from a sophisticated computer which stores
masses of information to a simple manual paper and pencil
procedure. One of the determining factors is the amount of
information contained in the cards 120 which must be stored, either
in an electronic memory or on paper, so that either a duplicate
card or the next card in series can be encoded at a later time.
In this embodiment of the invention, the combination code of each
card is divided into four parts which are used to designate the
type of card, the hotel and room number, an old code, and a new
code. The function of each of these various codes will be described
hereinafter in connection with FIGS. 11 and 12.
If a machine is employed to encode the cards, it will have a logic
portion, an active memory, a random number generator, thumb wheels
or other means for entering information, and a device for removing
or punching metal spots from the cards. When a new card is to be
encoded, the central layer 126 is inserted into the machine and the
type of card, such as a guest card, and the room number are
manually set into the machine by rotating appropriate thumb wheels.
The encoding machine will already have stored in its memory the
hotel code and the new and old codes for the last card of that type
issued for that particular room. The electronic encoding machine
will encode as the card's new code a random number from the random
number generator and the card's old code will be the previous
card's new code. When this information is provided, the encoding
machine will actuate the appropriate punches to remove selected
metal spots 128 from the middle layer 126 and thereby encode the
card with this information in binary form. The card is then
withdrawn from the encoding machine and laminated together so that
the middle layer 126 is concealed between the two outer layers 122
and 124.
If a duplicate card is desired, the same procedure is followed
except that both the old and new codes of the previous card are
recalled from memory and encoded in the old and new code positions
respectively of the duplicate card.
As previously mentioned, this procedure could be performed manually
by employing a pencil and paper to record the necessary information
and to remove the appropriate metal spots 128. While this would be
extremely time-consuming and awkward for use in a hotel, it might
be very well suited to home use.
THE CARD READER
The card reader 132 (FIGS. 6 and 7) is secured in the unit housing
20 beneath the slot 24 to receive cards 120, as shown in FIG. 2, a
printed circuitboard 134, mounted on the opposite side of the card
reader, provides electrical connection between the sensors
positioned within the card reader to the remaining circuitry
described hereinafter.
The card reader is composed of an electrically insulating,
nonmetallic material, such as plastic or the like, and has a
relatively thin planar wall 136 secured adjacent to the housing 20.
The opposed thicker wall 138 contains a predetermined pattern of
cylindrical sensor receptacles 140 which corresponds in size and
location to the pattern of metal spots and holes in the card 120.
Receptacles 140 terminate short of the recess 142 so that a thin
layer of plastic separates the sensor receptacles from a card
positioned in the recess to protect the sensors 154. A tab 144
extending into the recess 142 permits a data card to be inserted
only when its mating notch 130 is correctly positioned so that the
card holes and metal spots are aligned with adjacent cylindrical
receptacles.
Microswitch 146 in the bottom of card reader 132 is actuated by any
correctly inserted card to connect the batteries to the card reader
sensors.
A female printed circuitboard connector 148 at the bottom open end
of recess 142 receives an emergency override device or security
pass unit which will be explained hereinafter. Drain hole 150
through the bottom of the card reader and a similar drain hole 152
in the bottom of the housing 20 (FIG. 2) provide for moisture
drainage.
THE SENSORS
In the preferred embodiment of this invention, the sensors 154
shown in FIG. 8 are small cylindrical cup-shaped blocks of ferrous
metal, such as an iron compounds pot core, each having two coils
160 and 162 would between a raised rim 156 and a raised center post
158. A sensor is secured in each sensor receptacle 140, as shown in
FIG. 7, with the open end of the sensor cup adjacent the closed end
of the receptacle.
The leads from the coils are wired to printed circuitboard 134
where each sensor is connected to a separate sensor circuit 176
(FIG. 9) to produce signals representing a logical binary 1 or 0 in
response to the absence or presence respectively of a metal spot
128 adjacent the sensor. The coils 160 and 162 act as the primary
and secondary coils respectively of an iron core transformer. In
this embodiment of the invention, the coils are chosen so that the
turns ratio is 1 to 1 and the oscillator 164 provides intermittent
bursts of high frequency constant amplitude signal, about 3 volts,
through the tuned circuit of capacitor 166 and coil 160. Capacitor
168 has the same value as capacitor 166, about 0.047 microfarads,
so that the two circuits are tuned to about the same frequency when
there is no metal spot 128 present.
Diode 170 rectifies the induced signal to produce a direct current
output across capacitor 172 and resistor 174, about 1 megohm,
limits the output signal across capacitor 172, about 0.01
microfarads.
As is well known, when the oscillator 164 provides alternating
current through coil 160, which in turn induces an alternating
current in coil 162, an alternating magnetic field is set up
between the outer ring 156 and center post 158 of the sensor. If
nothing impedes this magnetic field, the signal across capacitor
172 will be relatively large, such as about ten volts. However,
when one of the nonferrous metal spots 128 is positioned adjacent
to and across the top of the sensor, opposing magnetic fields are
set up in the spot which change the mutual inductance between the
coils 160 and 162 and block out a large amount of inductive
transfer between the two coils, thus producing a much smaller
output, such as about 2 volts. Thus, the binary logical 1 may be
equated with the 10 volt output while the binary logical 0 may be
equated with the 2 volt output.
It will be apparent that by selectively removing metal spots 128, a
large amount of coded information may be stored in binary form on
each data card. This information is uniquely employed in this
invention not only to open the door lock but also to conveniently
change the previously set lock combination code without using any
means other than a new card provided to the new room occupant or
the like.
THE CENTRAL PROCESSING UNIT
The central processing unit 188 shown in FIG. 10 receives
electrical signals from the sensor circuits and the various
switches previously described to control the operation of the bolt
42 through motor 76, as will be described hereinafter in connection
with FIGS. 11 and 12. Various physical apparatus well known to
those skilled in the art may be employed as specific elements in
the block diagram of FIG. 10, and therefore only the function and
operation of these elements will be described in detail. It should
be noted that all of the elements shown in FIG. 10, except the
security pass unit 222, are conveniently contained on the
ciruitboard 134 or elsewhere within the unitary housing structure
20.
The correct insertion of any data combination card 120 into the
card reader 132 actuates power switch 146 which connects the
batteries 84 to oscillator 164. Multiplexer 190 receives the
various sensor circuit output signals, stores them in the proper
format, and signals code processor 194 that information is ready to
be processed. Code processor 194 then interrogates each multiplexer
switch over line 196 and receives the binary 0 or 1 signal over
line 192 for each sensor. The code processor compares the sensor
circuit outputs with the corresponding code information stored in
code processor memory 200 and received over line 198. Memory 200
includes both fixed and active portions, as will be explained
hereinafter. If comparison between the sensor circuit signals from
the multiplexer and the memory information shows that a card with
the appropriate code has been inserted into the card reader, the
code processor provides a signal over connection 202 to the motor
control logic 204 which in turn drives motor 76 in the appropriate
direction while taking into consideration the condition of the
various switches. Motor control logic 204 is also directly
connected to batteries 84 over line 206 so that the motor may be
driven in response to signals from the switches 98, 100, 106, 108,
110 and 114 over their respective connections 210, 212, 214, 216
and 218, as described hereinafter, even when a data card has not
been inserted into the card reader to actuate power switch 146.
Lock-out switch 114, previously described, provides the person
inside the door with security in all except emergency situations by
disconnecting the batteries 84 from motor 76 through motor control
logic 204. However, there must be at least one means of access from
the outside even where the lock-out switch is engaged in case the
occupant needs to be evacuated, as in a fire or the like.
Therefore, a security pass unit 222, shown schematically in FIG.
10, employs a male connector 224 which may be inserted through card
reader 132 to plug into female connector 148 at the bottom of the
card reader. The security pass unit has its own battery power
supply 226 to operate the motor 76 even when the batteries 84 are
disconnected by lock-out switch 114.
Security pass unit 222 contains its own read-only memory 228 which
has stored the information necessary to operate each decode unit
236 of every room lock. Battery 226 supplies power over connection
230 to control logic unit 232 which in turn interrogates the
individual room decode unit 236 over line 234 by sending clock
signals to the decode unit. The decode unit responds by sending a
unique serial code pattern to address the security pass unit
read-only memory 228 over line 238. Memory 228 in response supplies
signals from its addressed portions to logic unit 232 over line 240
where these signals are converted to serial form and transmitted to
the decode unit over line 234. When the comparator of decode unit
232 is satisfied, the decode unit connects battery 226 through the
logic unit to motor 76 to retract the bolt so the door can be
opened from outside. The bolt retraction also resets lock-out
switch 114 if it has been previously engaged.
The decode unit of each room always addresses a unique portion of
memory 228 which is different from the portion of memory addressed
by the decode unit of any other room. Read-only memory 228 has been
programmed to provide a unique response upon receiving the code
pattern for that particular room, but this response has been
randomly selected and bears no mathematical relationship to the
decode unit signal to memory.
Since each decode unit will recognize only one particular
combination of signals, and since this response is different for
each door and bears no mathematical relation to the interrogating
code pattern from the decode unit, it is difficult to break the
code for any door and should one code be broken, no other room will
be compromised as a result.
FIG. 11 is a flow diagram or chart showing the operation of the
code processor 194 and memory 200. FIG. 12 is a flow diagram
showing the operation of the motor control logic unit 204 and
associated switches. The beginning point P1 in FIG. 11 represents
the signals from multiplexer 190 resulting from the output of the
sensor circuits. The end point P2 in FIG. 11 represents the signal
of the code processor to motor control logic unit 204. This same
point P2 is one of the beginning points in FIG. 12. According to
the convention adopted in both FIGS. 11 and 12, the diamonds
represent information to be supplied or questions asked regarding
various logic conditions and the information or answers determine
the path to be taken to the next step. Thus, the word "yes" or "no"
is written adjacent to the arrows extending from each diamond to
indicate the logic condition or how the question contained within
the diamond has been answered and the resulting path to be
followed. The rectangles in FIGS. 11 and 12 contain instructions to
the various logic or memory elements involved and the instruction
is presumed to be carried out at that position in the flow diagram.
The arrows on the connecting lines indicate the direction of flow
of the steps through the diagram.
Referring now to FIG. 11, the sensor circuits are interrogated
through point P1 to first determine the type of data combination
card inserted in the card reader. Depending on how the system is
used, there may be one or more types of cards employed. In the
embodiment described herein where the system is employed in a
hotel, there are guest, maintenance, master and reset type data
combination cards. It will be apparent, however, that for home use,
for example, the maintenance and master cards may be eliminated and
thus the system simplified to that extent.
Since the guest card will be used most frequently, that card type
is first determined at 240. If the portion of the sensor circuits
assigned that function indicate a guest card, the answer is yes and
the sensor circuits are then interrogated to determine the hotel
and room number coded on the card. If the hotel and room number
code determined at 242 do not match the code fixed in that lock's
memory 200, the door will not unlock and the logic sequence will
repeat until the condition is satisfied by the correct hotel and
room number code being supplied. If the hotel and room number code
is correct, the new code part of the card will be compared at 244
with the new code part of the active portion of memory 200. If the
new codes match, a signal is generated at 246 to instruct the motor
control logic unit to retract the bolt 42. Since the new code of
the data card is a randomly selected number, it will match the new
code of the lock's memory only where that card is the same card as
was last used in the lock as, for example, where a guest is
reentering his assigned room.
Where the new code does not match, as when a new guest is using his
card for the first time, the card's old code is compared at 248
with the lock's new code. If the old code does not match the lock's
new code, the logic sequence will recycle the logic to 244 without
unlocking the door and repeat until a card is provided with either
a new or old code which matches the new code of memory 200. Where
the old code does match, the new and old codes of the card are read
into the active portion of memory 200 at 250 to change both the new
and old parts of memory respectively so that the card's new code is
now the memory's new code and the card's old code is now the
memory's old code. The new code parts of the card and memory are
then again compared at 252 and if they match, as they should since
the new code active memory has just been changed, a signal is
generated at 246 to retract the bolt. If for some reason the card
and memory new code parts still do not match, the logic repeats
back to 250 to read and store the card's new and old codes in
memory as previously described.
The above-described method of changing the new and old code parts
of the active portion of memory 200 automatically alters the lock
combination code without either connection to a remote central
control system or the necessity of hotel employees manually
changing the lock combinations every day. Instead, each new hotel
guest automatically changes the old and new code in the lock memory
of his assigned room upon inserting his new card the first time,
thus rendering inoperative all previously issued guest cards.
Returning to FIG. 11, if the data card is determined at 240 not be
a guest type card, the multiplexer is interrogated at 256 to see if
the card is the type issued to maintenance personnel, and if it is,
the hotel and room number code is compared at 258 to determine
whether that particular card is authorized to enter that room. The
maintenance card room number code may include a series of rooms,
for example, all rooms on one floor of a hotel, which an individual
is authorized to enter and service.
If the hotel and room number codes do not match, the logic will
repeat and the door will remain bolted. If, however, a match is
obtained at 258, the same sequence of steps will be followed as for
the guest card where the new codes are compared at 260 and if a
match is obtained, a signal is generated at 246 to retract the
bolt. This will be a common occurrence since maintenance personnel
are likely to be assigned to the same rooms for an extended period
of time. Where room assignments are changed and new maintenance
cards issued, the new codes will not match and the card's old code
is compared with the lock's new code at 262 and when found to
match, the card's new and old codes are read and stored into the
new and old code parts respectively of the lock's active memory at
264 so that the new codes will then match at 266 to generate a
retract bolt signal at 246. This same procedure automatically locks
out all previously issued maintenance cards.
As in most lock systems, provision is made for a master key or data
combination card which will unlock any door in the hotel from the
outside except when the lock-out switch 114 has been engaged. Thus,
if the card inserted in the card reader is neither a guest nor a
maintenance type, but is determined at 268 to be a master type,
only the proper hotel code needs to be matched at 270 since the
master card is to open all room doors. The flow chart operation
sequence for the remainder of the master card operation is the same
as for the guest and maintenance card operations previously
described, and therefore the remainder of the master card operation
shown schematically in FIG. 11 will now be specifically
described.
It will be apparent that guest, maintenance and master type cards
each address a different part of the active portion of memory 200
since each card type must be able to open the lock and change the
lock combination for that card type without changing the lock code
combination for any of the other card types.
A reset card is provided in the event that an authorized card will
not unlock a door, such as where a first guest or other type card
is issued but never inserted in the card reader. Neither the old
nor new code of the next second card issued will match either of
the lock's new or old codes since the lock's codes were never
updated by the first card. Since the second card will not unlock
the door, a reset card is encoded with the reset type code, the
hotel and room number codes, the type of the second card, and
randomly selected new and old codes. The reset type card is
determined at 272 and if the card is not a reset type, the logic
repeats until an authorized card type is inserted into the card
reader. After a correct reset type code is recognized at 272, the
hotel number code is compared at 274, and if it matches, the type
of reset desired (guest, maintenance or master) is determined at
276, 278 and 280 respectively. If none of these compare, the logic
will repeat without changing any memory. Where a match is obtained,
depending on the card type memory to be changed, the reset card's
new and old codes are read and stored into the appropriate parts of
the active portion of memory 200 as the new and old guest,
maintenance or master codes at 282, 284 and 286 respectively. The
door is not opened by the reset card, however, as indicated by
point A1 which repeats to beginning point P1 following each of the
code changes at 282, 284 and 286. Instead, a new card of the
appropriate type is encoded with the new and old codes just stored
in memory 200 and this latter card unlocks the door. Alternatively,
the new guest, maintenance or master card may be encoded with the
lock's new code as the card's old code and with a randomly
generated new code.
FIG. 12 shows the operation of the motor control logic unit 204.
Connection 206 supplies power from batteries 84 so that logic unit
204 can operate motor 76 without a card in the reader. This
situation, indicated at entry point P3, arises when the lock is
hand-operated from the inside and it becomes necessary to extend
the bolt. Entry point P3 leads to inquiry 290 as to whether power
switch 146 is on, which will be the case if any card is correctly
inserted in the card reader. Point P2 in FIG. 12 indicates a signal
received from the code processor to retract the bolt, as previously
explained in connection with FIG. 11, resulting from insertion of
an appropriately coded data card. Thus, to continue past point P2,
an authorized data card must be correctly inserted into the card
reader.
If the reader power switch is not on, magnetic switch 110 detects
whether the door is closed at 292. If the door is closed, it is
determined at 294 whether the door was last attempted to be opened
from the outside and if so, point A5 leads to a bolt extended
condition as will be explained hereinafter. If the last door
opening was not attempted from the outside, it is determined at 296
whether the last door opening was attempted from the inside, and if
not, this leads to an illegal or failure to satisfy condition and
the power is removed to stop the logic sequence at 298. If the last
door opening as determined at 296 was attempted from the inside,
the bolt is extended, as will be explained hereinafter.
Returning now to 292, if the door is not closed, it is again
determined at 296 whether the last attempted door opening was from
the inside. If it was not and is determined at 300 that the last
door opening was also not from the outside, an illegal condition
again ensues and the power is removed at 298. If the last attempted
opening was, however, from the outside as determined at 300, the
motor shaft is rotated counterclockwise at 302 to extend the bolt
to its latch position, that is, to extend the bolt 42 until only
the lug 72 extends beyond the door. The motor shaft rotation
continues until the latch is determined by switch 108 to be
extended at 304 and then the motor is stopped at 306 and the logic
sequence resets to point A2 to await closure of the door.
Whether or not the reader power switch is on, if the door is not
closed the flow chart leads to point 296. If the last attempted
door opening was from the inside, the cam direction switches 98 and
100 sense whether the bolt is fully extended at 308 and if it is,
point A6 leads to a removal of power at 344, as will be explained
hereinafter. If the bolt is not fully extended, it is detected at
310 whether the cams were turned clockwise or counterclockwise to
retract the bolt. If the cams were rotated counterclockwise, the
flow chart leads through point A3 to the instruction 302 to rotate
the motor shaft counterclockwise to close the bolt to its latch
position as previously explained. If, however, the cams were
rotated clockwise, the motor shaft is instructed at 312 to rotate
in the clockwise direction to extend the bolt to its latch position
at 314. The motor will continue to operate until the bolt is
extended to its latch position and will then stop at 316 and the
logic sequence will recycle through point A2 to wait for the door
to close at 318.
If the power switch is on at 290 and if a signal to retract the
bolt is received at point P2, it will be determined at 318 whether
the door is close. If no retract bolt signal is received a point
P2, the logic sequence will proceed no further since an
unauthorized card is in the card reader. If the door is not closed
at 318, the logic sequence proceeds to 296 to determine whether the
last attempted door opening was from the inside, as previously
explained. If, however, the door is closed, as where the occupant
is using his card to try to enter the room from the outside,
direction switches 98 and 100 indicate at 320 whether the bolt is
fully extended. If the bolt is fully extended, the motor control
logic is set at 324 to indicate, until changed, that the attempt to
enter the room is now from the outside. The motor shaft in this
embodiment of the invention is always rotated clockwise at 326 to
retract the bolt upon insertion of a correctly coded card until the
bolt is indicated to be fully retracted at 328, at which time the
motor is stopped at 330 and the logic sequence repeats through
point A4 to the beginning until the reader power switch is turned
off by removal of the data card.
If the bolt is not fully extended at 320, an inquiry at 334
determines whether a person with a card is still waiting to enter
from the outside. If he is, the logic sequence will repeat leaving
the bolt open until the card is withdrawn. If entrance was not last
attempted from the outside, as determined at 334, the direction of
cam rotation is detected at 336 and if the cams are rotated
clockwise, the motor shaft is rotated clockwise at at 338 to extend
the bolt. The logic sequence repeats through 340 until the bolt is
fully extended, at which time both the entered and exited mode
logic is reset to a zero condition at 342, the power is removed
from the motor at 344, and the logic sequence recycles through
point A4 to determine whether the power switch is still on. If the
cams have, however, been rotated counterclockwise, the motor shaft
is rotated counterclockwise at 346 to extend the bolt. When the
bolt is determined to have been fully extended at 348, the entered
and exited mode logic will again be reset to zero at 342, the power
removed at 344, and the logic sequence will repeat as previously
described.
While the invention has been illustrated and described in terms of
a particular embodiment, it will be understood that various
modifications and changes may be made without departing from the
actual scope of the invention.
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