Information
-
Patent Grant
-
6615625
-
Patent Number
6,615,625
-
Date Filed
Tuesday, January 25, 200024 years ago
-
Date Issued
Tuesday, September 9, 200321 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Chernoff, Vilhauer, McClung & Stenzel, LLP
-
CPC
-
US Classifications
Field of Search
US
- 070 2782
- 070 2783
- 070 2791
- 070 2787
- 070 283
- 070 2831
- 070 389
- 070 416
- 070 417
- 070 421
- 070 386
-
International Classifications
-
Abstract
An electronic locking system comprises a cylinder housed within and rotatable with respect to a shell. A key has a power supply. At least one of the key and the cylinder is capable of generating a signal when the key is electrically connected with the cylinder. An electrically powered locking mechanism is housed within the cylinder and includes a lock member moveable between an open position and a locked position. The lock member in the locked position interferes with movement of the cylinder. A power source is connected to the locking mechanism in response to the signal. The locking mechanism allows movement of the lock member from the locked position to the open position in response to the signal so that the cylinder may be rotated within the shell. The cylinder further includes an interfering member that resists movement of the locking member. In addition, a biasing mechanism urges the cylinder toward a home position when the cylinder is rotated away from the home position.
Description
BACKGROUND OF THE INVENTION
The present invention relates to an electronic lock.
Electronic locks have many advantages over mechanical locks. For example, electronic locks used in combination with a microprocessor or a computer can be programed to control the electronic lock by time of day, by authorization codes, or other factors that may be programed into the processor. When a key is lost, instead of replacing the electronic lock, the electronic lock may be reprogrammed to accept a different identification code from a different key.
However, electronic locks suffer from a number of drawbacks. First, the locks require a source of power. If the power source is provided within the lock, such as in the form of a battery, then the power supply occupies space within the lock, making the lock larger. Such batteries may also be prone to corrosion which can affect the internal parts of the lock. In addition, if the battery loses power, then the lock may no longer be able to function. Further, the lock must be accessed periodically in order to change the battery. Providing power from a standard electrical power line is an alternative, but requires providing wiring to the lock. Further, such wiring may not be available in some environments, such as a desk or cabinet.
It is also desired to make the locks as small as possible, so that the electronic lock may be installed in place of an existing mechanical lock. Conventional mechanical locks used with desks or cabinets are relatively small. Thus, the space available within such a lock is confined, limiting the size and number of components that may be used within a lock.
Another difficulty with electronic locks is that they are susceptible to opening in response to sharp blows. Typically, electronic locks use a solenoid. However, it is often possible to jar a solenoid plunger so that an electronic lock may be opened by applying a sharp force to the lock, such as striking a lock with a hammer.
Another problem with electronic locks is that often a solenoid is used to move a plunger into and out of interfering relationship with the internal cylinder and the external shell. This may result in several problems. First, the solenoid and its plunger must be constructed to withstand the primary force directed on the plunger when a person attempts to rotate the cylinder when locked. Another problem is that the electronic lock may be difficult to lock, since it may be difficult to align the plunger with its corresponding bore. If the plunger does not align properly with the bore, the plunger cannot enter the bore so as to interfere with the movement of the cylinder.
Yet another problem is that some electronic locks allow removal of the key during rotation of the lock. In that event, a person may forget to return the cylinder to its locked position after the lock has been opened.
Accordingly, what is therefore desired is an electronic lock that occupies a small volume, may be used to replace existing mechanical locks, that does not require a power source inside of the lock or external wiring, that is not susceptible to being opened in response to tampering, that may be consistently returned to a position that allows secure locking, and that prevents withdrawal of a key during operation.
BRIEF SUMMARY OF THE INVENTION
The present invention provides an electronic locking system that overcomes the aforesaid drawbacks of the prior art. In a first separate aspect of the invention, an electronic locking system comprises a cylinder housed within and rotatable with respect to a shell. A key has a power supply. At least one of the cylinder and key is capable of generating a signal when the key is engaged with the cylinder. An electrically powered locking mechanism is housed entirely within the cylinder and includes a lock member movable between an open position inside the cylinder and a locked position. The lock member in the locked position interferes with movement of the cylinder. The power supply is electrically connected to the locking mechanism. The locking mechanism allows movement of the lock member from the locked position to the open position in response to the signal, so that the cylinder may be rotated within the shell. All of the components of the locking mechanism are housed within the cylinder when the cylinder is rotated. Thus, this aspect of the invention has the advantages of providing a small lock that may be used to replace existing mechanical locks, and that does not require a power supply in the lock or external wiring to provide power.
In another separate aspect of the invention, an electronic locking system comprises a cylinder housed within and rotatable with respect to a shell. At least one of a key and the cylinder is capable of generating a signal when the key is engaged with the cylinder. An electrically powered locking mechanism in the cylinder includes a lock member that is moveable between an open position and a locked position. The lock member in the locked position interferes with movement of the cylinder. The locking mechanism further includes an interfering member moveable between an interfering position and a non-interfering position. The interfering member in the interfering position resists movement of the lock member, and the interfering member in the non-interfering position allows movement of the lock member. The locking mechanism moves the interfering member from the interfering position to the non-interfering position in response to the signal so that the cylinder may be rotated within the shell. This aspect of the invention has the advantage of using a two part system so that the lock member may be designed to withstand large primary forces, while the interfering member, which may be a solenoid, is not subjected to large direct forces.
In a third separate aspect of the invention, an electronic locking system comprises a cylinder housed within and rotatable with respect to the shell. At least one of a key and the cylinder is capable of generating a signal when the key is engaged with the cylinder. An electrically powered locking mechanism includes a lock member that is moveable between an open position and a locked position. The locking mechanism allows movement of the locking member from the locked to the open position in response to receiving the signal so that the cylinder may be rotated within the shell. A biasing mechanism urges the cylinder toward a home position when the cylinder is rotated away from the home position. This aspect of the invention has the advantage of aligning the cylinder to a position that will allow the lock to be secured.
Preferably, the electronic locking systems described above further include an anti-tamper mechanism to prevent the lock from being opened as a result of a sharp blow to the lock. In addition, the locking systems preferably further include a key retention mechanism that prevents the key from being disengaged from the lock when the cylinder is rotated away from the home position.
In addition to the advantages described above, the various aspects of the invention may each provide one or more of the following advantages. By housing the operative components of the locking mechanism entirely within the cylinder, a locking system may be manufactured to fit within a very small volume. Thus, the electronic lock may be used to replace conventional mechanical cylinder locks. In addition, in the event an installed lock fails, the cylinder may be replaced without replacing the entire lock. The present invention also does not require the use of a power supply within the lock itself. Thus, the lock can be smaller because it does not contain a power supply, and is not susceptible to corrosion resulting from a corroding battery. Nor does the lock require an external source of power from external wiring. The lock is thus simpler and easier to install.
The foregoing and other features and advantages of the invention will be more readily understood upon consideration of the following detailed description of the invention, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1
is a perspective view of an exemplary lock of the present invention.
FIG. 2
is a perspective view of an exemplary key.
FIG. 3
is a perspective view of an exemplary key engaging an exemplary core.
FIG. 4
is an exploded assembly view of an exemplary lock.
FIG. 5
is an exploded assembly view of an exemplary cylinder.
FIG. 6
is a cross-section of the lock of
FIG. 1
taken along a longitudinal line bisecting the cylinder.
FIG. 7
is a cross-section of the lock taken along the line
7
—
7
of FIG.
6
.
FIG. 8
is a cross-section of the lock taken along the line
8
—
8
of FIG.
6
.
FIG. 9
is similar to
FIG. 6
, except that the electronic lock has been opened.
FIG. 9A
shows a detail view of the key retention mechanism.
FIG. 10
is similar to
FIG. 6
, except that a large force has been applied to the face of the lock.
FIG. 11
is an exploded assembly view of an exemplary key.
FIG. 12
is a block diagram of the electrical components of an exemplary key and lock.
FIG. 13
is a flow diagram of the lock interface.
FIG. 14
is a flow diagram of the key interface.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the figures, wherein like numerals refer to like elements,
FIGS. 1
,
2
and
3
show an exemplary electronic locking system
10
, which consists of a lock
12
and key
18
. The lock
12
has a cylinder
14
that rotates within a shell
16
. A bolt
20
(shown in phantom lines) is attached to the rear of the lock
12
. In operation, the key
18
engages the lock
12
as shown in FIG.
3
. The key
18
and lock
12
communicate electronically, so that when an authorized key
18
engages the lock
12
, the cylinder
14
may be rotated within the shell
16
. Rotation of the cylinder
14
causes movement of the bolt
20
, enabling opening of the device that has been locked. For example, where the electronic locking system
10
is used with a desk drawer, rotation of the cylinder
14
would move the bolt
20
to a position wherein the desk drawer could be opened. The electronic locking system
10
may be used in any application where a lock would be desired, such as with doors, windows, cabinets, desks, filing cabinets, etc. The electronic locking system
10
may be used with any conventional bolt or equivalent apparatus used to secure the item to be locked.
THE KEY
FIG. 11
shows an exemplary embodiment of a key
18
of the present invention. The key
18
has an external housing
22
containing the components of the key
18
. The key
18
has a lock engaging rod
24
at the front end of the key
18
. The key
18
also has an annular neck
26
that defines a bore
130
opposite the rod
24
. Inside the housing
22
is a battery
28
, battery spring
30
, and printed circuit board
32
. Mounted on the printed circuit board is a microprocessor
132
, LED
36
and beeper
38
. Electrical contact is made between the key
18
and the lock
12
through the key pins
40
, which are electrically insulated by the insulator
42
. Coil springs
44
urge the pins
40
forward and into engagement with the lock
12
. The key pins
40
are electrically connected to the microprocessor and battery
28
.
The assembled insulator
42
, pins
40
, printed circuit board
32
, and battery
28
are held snugly within the housing
22
by use of the spring
46
and plug
48
. A gasket
50
seals the key
18
, which is pressed against the plug by the post
52
. A cap
54
seals the housing
22
. A torque amplifier
56
fits around the housing
22
, so that the key
18
may be easily gripped and turned.
The essential components of the key
18
are a power supply, such as battery
28
, and microprocessor, for communicating with the lock
12
. The mechanical assembly and electrical connections may be constructed as desired. Thus for example, while a rod
24
and annular neck
26
are shown, other mechanical arrangements could be used to allow the key
18
to engage the lock
12
so as to rotate the lock, such as a square peg.
THE LOCK
FIGS. 1
, and
4
-
6
illustrate an exemplary lock
12
.
FIG. 6
is a cross-section taken along a longitudinal line bisecting the lock
12
. The lock
12
is comprised of a cylinder
14
and a shell
16
. The lock
12
may be sized so as to replace conventional mechanical cylinder locks. A tail piece
58
(see
FIG. 6
) is attached to the end of the cylinder
14
with bolts or screws. A pair of bores
59
at the end of the cylinder
14
receive the bolts or screws for attaching the tail piece. (See
FIG. 5
) The tail piece
58
is connected to a bolt
20
, or other conventional locking device, which interferes with movement of the item to be locked. For example, where the lock
12
is used to lock a desk drawer, the bolt
20
would prevent movement of the desk drawer relative to the desk. The shell
16
may be made from any conventional material, such as brass, and includes a bible
60
projecting away from the cylindrical portion of the shell
16
. The bible
60
fits within a slot in the device to be locked, such as a desk drawer, to prevent rotation of the shell
16
with respect to the device. An o-ring
62
and a back seal
63
are used to seal the inside of the shell
16
to prevent dirt and other contaminants from entering the inside of the shell
16
and damaging the components of the lock
12
. A threaded retainer
64
is threadably attached to a threaded rear portion
66
of the cylinder
14
. The tension between the cylinder
14
and the shell
16
may be adjusted by tightening the retainer
64
, thus controlling the ease with which the cylinder
14
may be rotated within shell
16
.
The cylinder
14
is comprised of a body
68
to which is mounted the various components of the cylinder
14
. The front portion of the body
68
has two bores
70
, each of which contains an electrical contact
72
. The contacts
72
are insulated from the body
68
by insulators
74
. The electrical contacts
72
receive the pins
40
to provide the electrical connection between the lock
12
and key
18
, so that the key
18
may provide power to the lock
12
and so that the key
18
and lock
12
can communicate with one another.
A printed circuit board
76
is mounted at the center of the body
68
. The printed circuit board
76
includes the lock microprocessor and memory for the lock
12
. The printed circuit board
76
is electrically connected to the electrical contacts
72
.
A solenoid assembly is also mounted in the body
68
. The solenoid assembly includes a frame
78
to which is mounted a solenoid coil
80
. The coil
80
is aligned with a bore
82
at the rear portion of the body
68
. The solenoid assembly also includes a tube
84
containing a tamper element
86
, tamper spring
88
, solenoid plunger
90
, solenoid spring
92
and solenoid pole
94
. The assembled tube
84
is inserted into the bore
82
so that the lower portion of the tube
84
and solenoid pole
94
are located within the solenoid coil
80
. The tube
84
is made of brass or some other non-ferrous material. The tube
84
is retained inside of the bore
82
through the use of a lock ring
96
. The lock ring
96
fits within an annular groove
98
at the rear portion of the body
68
and another groove
100
at the end of the tube
84
. Drill guards
101
are mounted between the front portion of the body
68
and the solenoid frame
78
to protect the solenoid assembly from being drilled out.
The body
68
also includes a bore
102
that is perpendicular to and in communication with bore
82
of the body
68
and bore
85
of the tube
84
. Referring especially to
FIG. 6
, housed within the bore
102
is a pin
104
having a rounded head portion
106
and a lower rod portion
108
having a smaller diameter than the head portion
106
. The bore
102
has an upper portion
102
A that is sized so as to receive the rounded head portion
106
, and a lower portion
102
B having a smaller diameter sized to receive the lower rod portion
108
. A spring
110
fits within the upper bore portion
102
A. The spring
110
is wider than the lower bore portion
102
B, so that the spring
110
is compressed by movement of the rounded head portion
106
of the pin
104
as the pin
104
moves inside the bore
102
. Thus, the spring
110
urges the pin
104
out of the bore
102
.
Referring now especially to
FIG. 7
, the shell
16
defines a cavity
112
that communicates with the bore
102
when the cylinder
14
is in the shell
16
and located in the home, or locked, position. The cavity
112
is defined by a pair of opposing cam surfaces
114
A and
114
B. The cavity
112
is large enough to receive at least a portion of the head portion
106
of the pin
104
.
Collectively, the solenoid assembly, pin
104
, and spring
110
comprise a locking mechanism used to prevent or interfere with rotation of the cylinder
14
with respect to the shell
16
.
FIG. 6
shows the lock
12
in a locked condition. In the locked condition, no power is supplied to the solenoid coil
80
. The solenoid spring
92
urges the plunger
90
away from the pole
94
. The plunger
90
thus occupies the space in the tube
84
beneath the bore
85
. The rounded head portion
106
of the pin
104
is in the cavity
112
of the shell
16
. If the cylinder
14
is rotated with respect to the shell
16
, the rounded head portion
106
of the pin
104
engages one of the cam surfaces
114
A or
114
B. The cam surface
114
A or
114
B urges the rounded head portion
106
downward toward the bore
102
. However, because the plunger
90
occupies the space beneath the pin
104
, the rounded head portion
106
is prevented from moving completely into the bore
102
. Thus, in the locked condition, the cylinder
14
is unable to rotate with respect to the shell
16
due to the engagement of the rounded head portion
106
of the pin
104
with one of the cam surfaces
114
A and
114
B.
FIG. 9
illustrates the electronic lock
10
in an open condition. Power is supplied to the solenoid coil
80
. In response, the solenoid plunger
90
is retracted into the solenoid coil
80
and into contact with the pole
94
. Movement of the plunger
90
inside of the tube
84
creates an opening
116
within the tube
84
in communication with the bore
85
. This opening
116
is large enough to receive a portion of the lower rod portion
108
of the pin
104
. Thus, when the cylinder
14
is rotated with respect to the shell
16
, and the rounded head portion
106
of the pin
104
engages one of the cam surfaces
114
A or
114
B, the lower rod portion
108
is urged into the opening
116
. For example, if the cylinder
14
is rotated so that the head portion
106
engages the cam surface
114
A, the cam surface
114
A will cause the pin
104
to compress the spring
110
so that the head portion
106
is completely inside bore
102
and the lower rod portion
108
is partially inside the opening
116
. The cylinder
14
is thus free to rotate with respect to the shell
16
. This locking mechanism thus provides a significant advantage to the electronic locking system
10
. All of the locking components of the lock
12
, e.g. the microprocessor and locking mechanism, are housed within the cylinder
14
. Thus, each of these components is completely housed within the cylinder
14
when the cylinder
14
rotates with respect to the shell
16
. This provides several advantages. The lock
12
can be relatively small, and can be sized so as to replace conventional mechanical cylinder locks. In addition, in the event an installed lock
12
fails, the cylinder portion
14
of the lock
12
may be replaced without replacing the shell
16
.
Alternatively, other mechanical devices can be used to provide a locking mechanism. Instead of using a pin
104
, other lock members could be used having different shapes, such as bars, latches, or discs. The lock member may move in other ways. For example, the lock member may be pivoted about an axis so that a portion, when pivoted, interferes with rotation of the cylinder.
In the embodiment illustrated in the figures, the front face of the cylinder defines an annular groove
120
that receives the neck
26
of the key
18
. On one side of the annular groove
120
, the cylinder defines a bore
122
in communication with the annular groove
120
. The bore
122
is capable of receiving the rod
24
of the key
18
. The mating engagement of the bore
122
and the rod
24
ensure that the key
18
is properly aligned with the cylinder
14
. In addition, the rod
24
, when in mating engagement with the bore
122
, allows the key
18
to transfer torque to the cylinder
14
, minimizing the torque applied through the key pins
40
.
In a separate aspect of the invention, the electronic locking system
10
also has a unique anti-tamper mechanism. In normal operation, the tamper element
86
resides at the closed end of the tube
84
. A tamper spring
88
within the tamper element
86
frictionally engages the interior wall of the tube
84
, so as to resist movement of the tamper element
86
within the tube
84
. Thus, as illustrated in
FIG. 9
, when power is supplied to the solenoid coil
80
, and the plunger
90
is retracted, the tamper element
86
does not move. Thus, the tamper element
86
does not interfere with inward movement of the pin
104
into the opening
116
. However, as illustrated in
FIG. 10
, in the event of a sharp impulse force being applied to the front of the lock
12
, the tamper element
86
prevents the cylinder
14
from being rotated. A sharp force applied to the lock
12
may cause the plunger
90
to be momentarily retracted inside of the coil
80
by inertial forces. The same inertial forces cause the tamper element
86
to also move longitudinally with respect to the tube
84
. The tamper element
86
thus occupies the space beneath the bore
85
of the tube
84
, preventing the pin
104
from being pushed into the bore
102
by rotation of the cylinder
14
. Once the spring
92
overcomes the inertial forces which resulted from the sharp impact, both the plunger
90
and tamper element
86
are returned to their normal positions when in the locked condition as shown in FIG.
6
. Thus, the locking system
10
of the present invention has the advantage of preventing the lock
12
from being opened by merely striking the lock
12
with a sharp blow.
In another separate aspect of the invention, the lock
12
also has a biasing mechanism that urges the lock toward a home position in order to provide for increased reliability of the locking system
10
. In the embodiment shown in the figures, the “home position” of the lock
12
is defined by the cavity
112
. The cam surfaces
114
A and
114
B meet at an apex
118
. When the bore
102
of the cylinder
14
is aligned with the apex
118
, the cylinder
14
is in the home position. In the absence of external torque applied to the cylinder
14
, the cylinder
14
will naturally return to the home position once the head portion
106
begins to enter the cavity
112
. The spring
110
urges the head portion
106
against the cam surfaces
114
A or
114
B. As the head portion
106
engages one of these cam surfaces
114
A,
114
B, the cam surface
114
A or
114
B urges the head portion
106
toward the apex
118
, and consequently the cylinder
14
toward the home position. Once the head portion
106
reaches the apex
118
, it is at an equilibrium point, which is the home position. Likewise, when the cylinder
14
is rotated away from the home position, the biasing mechanism urges the cylinder
14
to return to the home position. This biasing mechanism provides additional advantages to the locking system
10
. When rotating the cylinder
14
back toward the home position in order to lock the lock
12
, the user of the locking system
10
is able to determine when the cylinder
14
has returned to the home position based on the changes in resistance to movement caused by compression of the spring
110
. When the home position has been located, the user may safely remove the key, knowing that the cylinder is in the correct position to be locked.
While the embodiment illustrated in the figures combines the locking mechanism with the biasing mechanism, the biasing mechanism could be separate from the locking mechanism. Thus, the biasing mechanism could be a separate mechanical member urged by a spring, elastomer or other biasing device into engagement with the shell. Alternatively, the biasing mechanism could reside inside the shell and be urged into engagement with the cylinder. For example, the biasing mechanism may be comprised of a spring and ball-bearing housed within a bore in the shell. In such an alternative embodiment, the ball bearing may engage a dimple in the exterior surface of the cylinder, and the dimple defines the home position.
In another separate aspect of the invention, the locking system
10
provides a key retention mechanism. The cylinder
14
also has a bore
124
that is perpendicular to the longitudinal axis of the cylinder
14
and is in communication with the annular groove
120
. The bore
124
receives a ball bearing
126
. The shell
16
defines a cavity
128
that is in communication with the bore
124
when the cylinder
14
is in the home position. The neck
26
also has a bore
130
that is opposite the rod
24
. When the neck
26
is inserted into the annular groove
120
, the bore
130
is aligned with the bore
124
. The bore
130
is sized so that the ball bearing
126
may be received within the bore
130
. When the neck
26
is first inserted into the annular groove
120
, the ball bearing
126
is first pushed up into the cavity
128
. However, once the neck
26
is fully inserted into the groove
120
, the ball bearing drops back down inside the bore
124
and inside the bore
130
in the neck
26
. When the cylinder
14
is rotated, the ball bearing
126
sits completely within the bore
124
, and thus is housed within the cylinder
14
as the cylinder
14
is rotated. The ball bearing
126
prevents the key
18
from being withdrawn from the cylinder
14
once the cylinder
14
is rotated past the home position. The interior surface of the shell
16
prevents the ball bearing
126
from moving upward in the bore
124
, thus preventing the neck
26
from being withdrawn from the groove
120
. The only position in which the key
18
may be disengaged from the cylinder
14
is when the cylinder
14
is returned to the home position, so that the ball bearing
126
may be pushed up into the cavity
128
, thus allowing the neck
26
to be withdrawn from the groove
120
. Thus, the key retention mechanism provides the advantage of preventing the key
18
from being withdrawn from the lock
12
unless the cylinder
14
is returned to the home position. This ensures that the cylinder
14
is aligned properly so that the locking mechanism may be locked so as to prevent or interfere with rotation of the cylinder
14
with respect to the shell
16
. Alternatively, other key retention mechanisms could be employed to retain the key
18
in the cylinder
14
when the cylinder
14
is rotated with respect to the shell
16
. For example, the key could have a projecting tab which is received within a slot having an opening sized to receive the tab, allowing the key to rotate but preventing removal of the key except when the tab is aligned with the opening.
KEY AND LOCK COMMUNICATION
The key
18
and lock
12
communicate through the key pins
40
and the electrical contacts
72
. Referring to
FIG. 12
, the key
18
has a microprocessor
132
, a memory
134
in the form of Electronically Erasable Programmable Read Only Memory (EEPROM) which is connected to the microprocessor
132
. Collectively, the microprocessor
132
and associated memory
134
comprise a computer system. The computer system which may be used in the present invention may be any device, whether a microprocessor alone or in combination with other processors and/or memory devices, which performs the functions described herein relating to the reading, writing, deleting, storing, and/or comparing of information relating to key identification codes, passwords and other data. The key
18
further optionally includes an LED
36
, beeper
38
, battery
28
, and clock
136
.
The lock
12
also has a microprocessor
138
and associated memory
140
in the form of EEPROM. Like the key, the microprocessor
138
and associated memory
140
comprise a computer system. Power and communications are delivered to the lock microprocessor
138
over a single line through one of the pins
40
and contact
72
. The power passes through a diode
142
and filter capacitor
144
before entering the microprocessor
138
. The lock may also optionally include an LED, beeper and/or clock.
In operation, the key microprocessor
132
and lock microprocessor
138
communicate with one another to allow the lock
12
to be unlocked. In one embodiment, both the key microprocessor
132
and the lock microprocessor
138
are capable of storing passwords, and key identification codes and lock identification codes respectively. Each key
18
and lock
12
has a unique identification code. The identification codes may be programed in the respective microprocessors when the key
18
or lock
12
is manufactured. Referring now to
FIGS. 13 and 14
, when a key
18
engages a lock
12
, the key
18
sends power to the lock microprocessor
138
. After the lock microprocessor
138
has stabilized, the lock microprocessor
138
sends out a handshake signal to the key microprocessor
132
. The key microprocessor
132
sends a handshake signal back to the lock microprocessor
138
. The lock microprocessor
138
then sends a signal corresponding to its identification code to the key microprocessor
132
. The key microprocessor
132
then sends a key identification code and a password to the lock microprocessor
138
. The lock microprocessor
138
determines whether the key identification code is authorized to open the lock
12
, and then determines whether the password is correct. If so, the lock microprocessor
138
sends a signal to the key microprocessor
132
, which in response provides power from the battery
28
through one of the pins
40
and contacts
72
to the solenoid
80
to unlock the lock
12
.
Both the key microprocessor
132
and lock microprocessor
138
may store within their respective associated memories
134
and
140
activities occurring with respect to the key
18
and lock
12
. Thus, the lock memory
140
may contain data representative of each key
18
which has attempted to open the lock
12
, the time when the event occurred, the password that was supplied, and/or whether the lock
12
was opened. Likewise, each key
18
may store in its memory
134
each lock
12
that was accessed, the password provided to the lock
12
, the time the lock
12
was accessed, and/or whether the lock
12
opened. The key microprocessor
132
and lock microprocessor
138
may be programmed using a programming device such as a Palm Pilot™ sold by 3 Com®. Data may be communicated over a cable using an RS 232 communication standard, or may also be transmitted using any other standard method for transmitting digital information.
The system can also be designed to utilize multiple access levels. Thus, some keys may only be authorized to open a limited number of locks, while other keys may be master keys capable of opening all locks.
The electronic locking system
10
may include an LED which may be used to indicate the status of the lock
12
or key
18
, such as that an authorized key has been detected and that the lock
12
may be opened, or that the battery power is low. The electronic locking system
10
may also include a beeper to similarly communicate the status of the key
18
and/or lock
12
. The beeper may be used to communicate, for example, when a master key has been detected, when an authorized key is detected, when a key code has been added to the authorized key codes in memory, and/or when a key identification code has been deleted from a lock memory. The beeper may also be used to sound an alarm in response to an attempt to open the lock
12
without first using an authorized key.
The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims which follow.
Claims
- 1. An electronic locking system, comprising:(a) a cylinder housed within and rotatable with respect to a shell; (b) a key; (c) at least one of said key and said cylinder being capable of generating a signal when said key is electrically connected with said cylinder; (d) an electrically powered locking mechanism in said cylinder including a lock member movable between an open position and a locked position, said lock member in said locked position interfering with rotation of said cylinder with respect to said shell; and (e) an anti-tamper mechanism, said anti-tamper mechanism selectively resisting movement of said lock member in response to longitudinal movement of said cylinder.
- 2. The electronic locking system of claim 1 wherein said locking mechanism further comprises an interfering member selectively interfering with movement of said lock member.
- 3. The electronic locking system of claim 1 further comprising a biasing mechanism urging said cylinder toward a home position when said cylinder is rotated away from said home position.
- 4. The electronic locking system of claim 1 further comprising a key retention mechanism located at least partially within said cylinder that retains said key when said cylinder is rotated past a home position.
- 5. The electronic locking system of claim 1 wherein said locking mechanism is rotatable in unison with said cylinder when said lock member is in said open position.
US Referenced Citations (109)
Foreign Referenced Citations (4)
Number |
Date |
Country |
0128991 |
Dec 1984 |
EP |
0290330 |
Nov 1988 |
EP |
1 525 033 |
Sep 1978 |
GB |
2 119 548 |
Nov 1983 |
GB |