Note: Descriptions are shown in the official language in which they were submitted.
BD-190
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~071769
ELECTRONIC COMBINATION LOCK AND SYSTEM
:
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 distri-
buted 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 conven-
tional mechanical lock and key system now in general use.
However, it will be understood that the system of this inven-
tion could be used with any building or enclosure requiring
a locked door, such as safe deposit boxes or automobiles.
In typical electronic systems for controlling
entrance to protected areas, a door is provided with an elec-
tronic 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 signifi-
cant 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,
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107176g
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 elec~ronic systems where the central con-
trol unit is not employed, the individual lock combinations
on each door must be individually changed by manually reset-
ting the switches or changing electrical connections before
a new card will operate the lock. ~here 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 pre-
vious 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 rota-
` ting 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,
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1071769
but employ spring-loaded bolts to allow the bolt to be retrac-
ted when the doox is being closed and extended again after
the door is closed.
In brief, arrangements in accordance with the present
invention provide a unitary self-contained electronic combina-
tion lock which includes a dead bolt manually operable from
one side and operable from the other side only in response to
insertion o 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 inde-
pendently changed to render inoperative all previously-issued
data cards.
A method of comparing codes înserted into a combina-
tion 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 r
; 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
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a match signal is generated and the active memory is changed
to replace the previously~stored ~irst 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--inear 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 lockls mechanical linkage is not
normally accessible from outside the housing.
In one embodiment of the invention, a data combina-
tion card carries code information to be inserted into the
lock. The data card has a central coded layer secured
between the 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
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` 1071769
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 respec-
tive transformer second coils to provide a combination code
of first and second output signals correspondin~ to the infor-
mation 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
20 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
3~ and system.
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~`-; 107~769
According to the invention there is provided a method of
operating an electronic security system comprising the steps of:
storing a first and a second combination in an active memory, applying
third and fourth combinations to be compared therewith, comparing at
least one of the stored first and second combinations with at least one
of the applied third and fourth combinations other than comparing the
second and third or the fourth and first combinations, generating a
first match signal when the aforesaid compared combinations are identical,
utilizing said first match signal to open a security device when the
aforesaid compared combinations are identical, comparing the stored
second combination with the applied third combination when the aforesaid
compared combinations other than the second and third or the fourth and
first combinations arè not identical, generating a second match signal
when the second and third combinations are identical, and utilizing said
second match signal to change the active memory to store the third and
fourth combinations in place of the first and second combinations,
respectively, when the compared second and third combinations are identical.-
According to another aspect of the invention ~here is provided
an electronic security system comprising: a security device, an active
memory for storing at le~st one coded combination, receiving means for
receiving coded means carrying first and second applied coded combinations,
first comparison means for comparing at least one combination stored in
said memory with at least one of said first and second applied combinations, :
.~ and generating a first match signal when the aforesaid compared combinations
~- are identical, operating means responsive to said first match signal for
operating said security device, second comparison means for comparing a
combination stored in said memory with said first applied combination
when the first compared combinations are not identical, said second
compared combinations differing from the first compared combinations,
and generating a second match signal when said second compared combinations
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~ -- 1071769
\
are identical, and combination changing means responsive to said second
match signal for storing said second applied combination in said memory
in place of the stored combination identical to the first applied
conbination.
According to another aspect of the invention there is provided
a card for providing coded information to means for receiving and sensing
the information, wherein said means comprises at least one sensing coil
and means for positioning the card in relation to the at least one coil,
said card comprising a substrate of electrically non-conductive, non-
magnetically reactive material, and a layer of magnetically reactive
material adapted to be encoded by the selective removal of a portion of said
magnetically reactive material from at least one of a plurality of positions,
said positions being arranged in a predeterminedpatte~rn,said at least one
position being adapted to be aligned with and position adjacent said at
least one coil, said layer of magnetically reactive material overlying a
limited portion of one ~ide of the substrate and the substrate being adapted
to be folded over onto itself to form a composite card with said magnetically ~ .. r
reactive layer between two portions of the substrate, said card having
means for laminating the two portions together in said folded position.
According to another aspect of the invention there is provided a
card for providing coded information to a card reader adapted to receive a
card wherein said card reader comprises a housing, an alternating current
source and sensing means including a plurality of sensing coils connected
to said alternating current source and mounted in said reader housing
adjacent an inserted card, each coil having a ferromagnetic core and an
annular ferromagnetic sleeve encircling the coil, said card comprising a
thin substrate of electrically non-conductive, non-magnetically reactive
material and a thin layer of magnetically reactive material secured to at
least a first portion of one side of said substrate, ~aid layer having at
least one hole formed in one of a plurality of positions in said magnetically
reactive layer, said at least one hole and portions of the remainder of the
magnetically reactive layer constituting coded information, said substrate
~ ~5br
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,
having a second portion of said one side folded about an edge contiguous
with the first portion to cover said at least one hole without increasing
the amount of magnetically reactive material at said covered hole, said
folded portions being laminated together so that removal of one of the
portions will destroy the coded information, said card having means whereby
the positions in the layer are aligned with said coils.
According to another aspect of the invention there is provided
a card for providing coded information to means for receiving and sensing
the information, wherein said means comprises at least one sensing coil and
means for positioning the card in relation to said at least one sensing
coil, said card comprising a substrate of electrically non-conductive, non-
magnetically reactive material and a predetermined pattern of positions formed
by the relative presence and absence of areas of magnetically reactive material
overlying at least a first portion of one side of the substrate, said posi-
tions being adapted to be aligned with and positioned adjacent to said at
least one coil, said substrate having a second portion of said one side which
- when folded about an edge contiguous with the first portion covers at least
a first side of said positions without increasing the amount of magnetically
reactive material at said positions, said card having means for laminating
the portions together in a folded position to form a composite card with said
area.~ of ma~netically reactive material substantially between said two portions
of the substrate.
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.-;~ ; : .,,
1071769
FIG. l is a perspective view of the unitary elec-
tronic lock and system of this invention installed in a door;
FIG. 2 is a cross-sectional elevation view of a
preferred embodimen~ of the invention taken along the line
2-2 of FIG. l;
~ IG. 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;
-20 - 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 elec-
trical 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 logic operations of
the motor control lo~ic unit and associated motor of FIG. 10.
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~071769
The particular embodiment of the invention illus-
trated 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
t processing unit. These functional sections are described in
order herein to assist in understanding the structure and the
; inter~related functions of the various sections.
~ THE LOCK
Fig. 1 shows the entire electronic lock system of
~3 this invention eontained in a unitary housing 20 and-installedin 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 with~
;~ stand weathering and also resist attempts to break through
the lock from the outside. All of the necessary items for
J operation of this system, except the data card carried by the
?J 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
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107~'769
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 appropriately 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 appro-
priate 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. ~dditional 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
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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
; 20 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 by 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
~071769
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 from its position ~hown 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 around the periphery of the cam. Upon further r
ro~ation 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 hGusing 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 6~. 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 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
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,. .
damaging the motor. Since there is also a straight spur gear
drive from the motor 76 to cam plate 38, there is no impedi-
ment to opening the do~r from the inside whether the motor is
on or off.
To open the door from the outside, a data combina-
tion card 120 is inserted into slot 24 to actuate the elec-
tronic 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 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 ~riction 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 lOOA ride along the
periphery of the cams 90 and 92 respectively (Fig. 3). The
microswitch roller bearings are aligned along a horizontal
~ ' . !
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axis so that they are both positioned at 102 in their respec-
tive recesses when the bolt 42 is fully extended.
As may be seen in Fig. 3, microswitch arm 98A rests
at one end of cam recess 91 when the cam 38 is fully rotated
in the counterclockwise direction. ~icroswitch arm 98A con-
tinues to ride in recess 91 as cam 38 begins to rotate clock-
wise until bolt 42 is fully extended and cam 38 centered so
that microswitch arm lOOA, 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 cf recess 91 while switch arm
lOOA continues to ride in recess 93. In this manner, miçjro-
switches 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 p~in
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
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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
i~ 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
, 10 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 lOOA 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
-- 20 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 lO~A indi-
cates 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 wqll
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
~071769
entry from outside through the use of any card. When switch r
114 is actuated, its switch arm 114A is mov~d 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
:j 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 six
volt, forty milliamp motor has been found to operate satisfac-
torily 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 pre-
ferred 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 lamin-
ated together, some of the metal spots are punched out or
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- 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
i 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 combina-
tion 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 la~er 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.
ll 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 informa-
tion, and a device for removing or punching metal spots from
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the cards. When a new card is to be encoded, the centrallayer 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 h~ve 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.
HE CARD READER
The card reader 132 (Figs. 6 and 7) i9 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
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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 sep-
arates 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
20- 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 herein-
after. 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) provides 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,
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each having two coils 160 and 162 would between a raised rim
156 and a raised center post 158. ~ 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 cir-
cuitboard 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 three 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 O.Ol 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
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':
,
` sensor, opposing magnetic ~ields are set up in the spot whichchange 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 two
volts. Thus, the binary logical "1" may be equated with the
ten volt output while the binary logical "0" may be equated
with the two 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 herein-
after 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 unction 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 circuitboard 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
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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 fi~ed and active portions, as will be explained herein-
after. 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 respec-
tive 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 emer-
gency 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 evacu-
ated, as in a fire or the like. Therefore, a security pass
unit 222, shown schematically in Fig. 10, employs a male
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,. .
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 seria~ 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
- 20 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 por-
tion 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 partic-
ular combination of signals, and since this response is
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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
Pl in Fig. 11 represents the signals from multiplexer l90
resulting from the output of the sensor circuits. The end
point P2 in Fig, 11 represents the signal of the code proces-
sor 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 regard-
ing 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.
~ eferring now to Fig. 11, the sensor circuits are
interrogated through point Pl to first determine the type of
data combination card inserted in the card reader. Depending
on how the system in used, there may be one or more types of
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cards employed. In the embodiment described herein where
the system is employed in a hotel, there are guest, mainten-
ance, 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 num-
ber 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
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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 bo~t.
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 automati-
cally alters the lock combination code without either connec-
tion 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 inopera-
tive all previously-issued guest cards.
Returning to Fig. 11, if the data card is determined
at 240 not to be a guest type card, the multiplexer is inter-
rogated at 256 to see if the card is the type issued to main-
tenance 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 auth-
orized to enter and service.
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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
are 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 deter-
mined 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 ~he 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 not be specifically described.
~t will be apparent that guest, maintenance and
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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 auth-
orized 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 resettype, the logic repeats until an
authorized card type is inserted into the card reader. After
a correct reset type code is recognized at 262, 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 Al which repeats to begin-
ning point Pl 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,
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and this latter card unlocks the door. ~lternatively, 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 herein-
after. 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.
1071~69
Returning now to 292, i~ 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 out-
side as determined at 300, the motor shaft is rotated counter-
clockwise 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 ~2 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 countercloc~wise 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 posi-
tion 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
~071769
wait ~o~ the door to close at 3I8
If the power switch is on at 2~0, and if a signal to
retract the bolt is received at point P2, it will be determined
at 318 whether the door is closed. If no retract bolt signal
is received at 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 hi~ 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 embodi-
ment 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 deter-
mined 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 338 to extend the bolt. The logic
sequence repeats through 340 until the bolt is fully extended,
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at which time both the entered and exited mode logic is reset
to a æero 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.
~30
