Door lock control system featuring a remote control for a pneumatically powered door lock mechanism

A remote control station and integrally installed electronic control circuit for use with a bolt and lock mechanism is set forth. In the lock, an air supply connected with first and second solenoid valves is incorporated and has a rod which extends to manipulate the bolt; bolt position is indicated by a switch means determining movement of the bolt to the deadlock position, and a door position switch is also incorporated. Various control signals are formed and are interlocked so that remote control or key switch control of the lock mechanism is obtained. It is implemented by providing control signals to the solenoid valves. They cause the bolt to move between the deadbolt and retracted positions, or to the intermediate slamlock position.

BACKGROUND OF THE DISCLOSURE 
This disclosure is directed to a door lock system and in particular one 
which is able to positively control a door lock with interaction between 
key switching, remote control and a sensor determining door position. This 
is particularly intended for use with doors cooperative with a door frame 
in remotely controlled door lock systems of the sort installed in jails, 
bonded warehouses and other facilities. One typical facility involves a 
remotely located person who may view one or many doors as would occur in a 
bonded warehouse having multiple tenants where each tenant has an isolated 
area for storage of their goods, and another common application is in 
jails or prisons. 
The present apparatus is particularly concerned with control of a door lock 
which is installed optionally in a door frame but preferably in a door. 
That is, the door frame is metal door frame installed in a wall and which 
supports lock control system of the present disclosure. Thus, the door 
supports a lock which has a bolt which moves between any three positions. 
One position is fully retracted, and another position is the deadlock 
position. The deadlock position involves extension of the bolt and holding 
it in the extended state so that it cannot be retracted. The intermediate 
position involves the slamlock position where the bolt is extended, but it 
is not locked so that it can slide out of the way and then re-extend. This 
is the position achieved prior to closing the door, as the door is closed, 
the striker plate engages the bolt to gently slide it back into the lock 
and will thereafter permit the bolt to re-extend through the striker 
plate. Typically, the bolt will then be switched to the deadlock position. 
In any event, all the foregoing is accomplished in a sequence subject to 
several modes of control discussed below. 
One control mechanism is operation by a key which is inserted into the lock 
mechanism. To that end, the present system incorporates such a key. In 
addition, however, there is a remotely located control station which can 
be a few feet or many feet away. It is typically located for remote 
control by a person who normally has visual observation of the locked 
door. In any event, it is remotely connected to provide a remote 
indication of the status of the lock and subjects the lock to remote 
control. There is an interlock which is known as the door position switch 
(DPS) which senses whether or not the door is actually fully closed. It is 
possible for the door to appear at a distance to be fully closed when it 
is slightly ajar. In this system, the DPS determines that the door has 
been fully closed so that the bolt, whether extended or not, is aligned so 
that it can extend through the striker plate and accomplish latching. This 
system is particularly useful in a lock system involving pneumatically 
powered lock mechanisms. In that instance, the system includes a deadlock 
position switch within the lock which provides a signal that deadlocking 
has been accomplished. Moreover, it also incorporates solenoid valve 
controllers which provide air to a double acting piston and cylinder 
arrangement so that the piston positively controls the bolt, that is 
extending and retracting the bolt between the deadlock position, the 
slamlock position and the retracted position. 
The control system of the present disclosure involves a very small 
electronic component which can be easily installed within the lock 
mechanism, occupying very little space, and which is provided with 
electrical power for its operation from the remote station. The remote 
control station includes simple switches and thus connects with a minimum 
number of conductors. 
The present apparatus is summarized as an electronic component which is 
installed in a lock mechanism and which cooperates with a key switch on 
the lock mechanism. It also cooperates with a pneumatic actuator which is 
a double acting cylinder subject to control of a pair of solenoid valves 
to cause extension and retraction. That is connected with the door lock 
mechanism including the bolt. Preferably all this equipment is installed 
in the door frame although it can be installed in the door if essential. 
It is preferable to install in the frame so that it is fixed. It 
incorporates a remote control station which provides power for the 
electronic components. The DPS is mounted so that it can test the door for 
full closure.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Going first to FIG. 1 of the drawings, the lock control system of the 
present disclosure is identified by the numeral 10 and is that apparatus 
which is primarily located within the dotted line. It cooperates with a 
door frame 11 and an adjacent door 12. The door supports a striker plate 
13 which has an opening 14 formed therein to receive a bolt 15. In this 
deployment of the equipment, the door is moveable relative to the frame 
and supports the striker plate. The bolt 15 is mounted in the door and the 
lock control system 10 are mounted in the door frame. An alternate 
arrangement can position both the bolt and lock control system in the door 
or door frame. It is however preferable to locate the lock control system 
in the door frame where movement is not required. If it is located in the 
door, certain electrical conductors and a pneumatic supply line must 
extend either through the hinge or otherwise pivot to provide air and 
electrical power to the movably mounted equipment within the door. 
A DPS (door position switch) 16 is located relative to the door and door 
frame so that it senses full closure of the door. It is normally mounted 
on the frame recessed in a location for engagement by full closure of the 
door. It is located so that partial closure will not be sufficient to 
operate this switch. In other words, operation occurs only when the door 
is brought to a full closed position. 
A suitable pneumatically powered construction is set forth in application 
Ser. No. 07/308,241 which was filed on Feb. 8, 1989 and which is 
incorporated herewith in its entirety. FIG. 1 shows additionally a remote 
control station 18 which is installed between a few feet and several 
hundred feet away. It is connected by suitable wiring which connects with 
the electronic components shown within the dotted line at 10. 
Additionally, the numeral 19 identifies an air supply which provides air 
to a pneumatic cylinder 20. It encloses a piston 21 which extends a piston 
rod 22. The rod 22 operates in conjunction with the bolt 15 to provide 
deadlocking. In one operative mode, the cylinder accomplishes deadlocking 
of the bolt; in another position, the bolt is unlocked by operation of the 
cylinder 20. This moves the bolt to the slamlock position or to the 
retracted position. Three positions are achieved by the cylinder. If 
desired, two single acting cylinders can be used to accomplish the three 
positions. The cylinder is provided with pneumatic power delivered to both 
ends of the cylinder by appropriate solenoid control valves to be 
described. 
The lock system incorporates a key switch 24. This switch is operated by a 
key which is inserted into the lock by personnel who are provided with 
such a key. On operation, the key switch is closed and provides a signal 
of key switch operation. The significance of this will be understood more 
readily hereinafter. In addition to that, the bolt position, namely 
whether it is deadlocked or unlocked, is indicated from the bolt 15 or 
preferably by the piston rod 22. This is accomplished at a switch 25. This 
is the deadlock position switch or LBS hereinafter. The LBS 25 is mounted 
at an appropriate location to sense the accomplished movement of the 
equipment within the lock assembly whereby deadlocking is accomplished. 
Only when deadlocking has been accomplished is a signal provided through 
the LBS 25. This forms the appropriate signal as described above. 
The present system includes a first solenoid valve 26 and a second solenoid 
valve 27. They are connected to deliver air under pressure to opposite 
ends of the cylinder 20. They are in turn operated by solenoids which are 
shown at remote locations. It will be understood that the two solenoids 
are constructed integral with the valve assemblies. They serve as 
electrically powered operators for the respective valves. The valves must 
be provided with electrical power for operation. The two valves are 
switched as required to drive the piston 21 to any of three positions in 
the cylinder. In the preferred embodiment, the valves 26 and 27 are 
three-way valves. That is, each is provided with air from the air supply 
and another opening is a vent. This evacuates the cylinder so that the 
piston can travel to both ends of its stroke. 
Attention is now directed to FIG. 2 of the drawings which shows in greater 
detail the circuitry which was indicated in the block diagram schematic in 
FIG. 1. In addition, certain connections are also included. FIG. 2 is 
perhaps best understood in conjunction with the various inputs and outputs 
shown in the timing chart of FIG. 3. In any event, a description of the 
circuitry shown in FIG. 2 will be given first, and its operation will be 
understood in greater detail hereinafter. Going now to FIG. 2 of the 
drawings, a circuit is shown which utilizes two timer circuits IC1 and IC2 
which are preferably identical in construction. A timing function is 
obtained by imposing the selected RC timing circuit thereon. The circuit 
IC1 operates as a latch because it lacks a RC timing circuit. Both of the 
timing circuits IC1 and IC2 are provided with a reset signal at the pin 4 
and form output signals at the pin 3. A set signal is input to each at pin 
2. The power input terminal is pin 8. The RC input terminal is at terminal 
6 or 7, and it will be observed that no connection is made for IC1 at 
those pins. The circuit additionally includes the various resistors, 
capacitors and diodes shown as illustrated. Additionally, there are the 
transistors T1 through T9. The transistors T2 and T9 are used as switching 
elements, not amplifiers, and accordingly, they are driven completely to 
saturation. 
Operation of the present apparatus should now be considered. If the door 12 
of FIG. 1 is open, the initial conditions that prevail are the DPS 16 is 
open and B+ is not input to the transistor T2, the LBS (lock bolt switch) 
25 is open indicating that the lock bolt 15 is in the slamlock position, 
the relay RY is de-energized which forms an unlock lamp signal at the 
remote control station, and there is no power to the solenoid valves, and 
hence both valves 26 and 27 have no power for operation. 
One protective feature of the present system is protection of the bolt 15. 
The bolt 15 is constructed to withstand slamming as it moves from the 
slamlock position to the deadbolt position. Bolt movement occurs when the 
door or gate is slammed vigorously. However, it is possible that damage 
may occur if the bolt is extended and is in the deadlock position. 
Sabotage is prevented, i.e. a person cannot move the bolt to the deadlock 
position while the door is open. If one were to do this, the following 
interlock would occur, thereby preventing damage while slamming the door 
with the bolt extended in the deadlock position. The open gate is sensed 
by the DPS 16 which forms an open signal and thus, the timer IC1 is not 
triggered and the output signal at the pin 3 is therefore low. The LBS 25 
is sensitive to operation of the bolt to the deadlock position. The pin 3 
of IC1 connects to T4 and a signal is formed which switches the transistor 
T4 to a conducting state, in turn providing conduction to the transistor 
T6 and in turn providing current to the solenoid 26. The solenoid 26 is 
connected to the pneumatic system for operation to cause pneumatically 
controlled unlocking of the deadbolt. That is, the bolt is converted from 
the deadlock position into the unlock position. This in effect changes the 
operative condition of the bolt 15 from the deadlock position to the 
slamlock position. Once this is accomplished, the circuitry returns to its 
neutral state. The foregoing sequence is shown in the timing chart by the 
signal 30 which is input from the LBS 25 and which causes formation of the 
pulse 32 which is directed to the solenoid 26. The pulse is relatively 
short and need only be sustained for a short fraction of a second to 
assure that pneumatic operation is completed whereby the solenoid 26 is 
operated to provide the waveform 32 which is the unlock signal. 
DOOR CLOSURE AND RESULTANT SIGNALS 
Assume that the door 12 is properly closed. If so, the following signals 
occur. B+ is input from the DPS 16 and switches on the transistor T2 which 
provides the set signal for the time IC1. In addition, this input signal 
to the base of T2 is likewise supplied through the diode D6 and the 
switching transistor T10. This operates the circuit IC2 which forms an 
output at pin 3 to switch on the transistor T7, switching on the 
transistor T8 and supplying current to the solenoid 27. This brings the 
bolt 15 to the deadlock position. In addition, this movement operates the 
switch 25 to indicate operation of the bolt. This inputs the signal back 
through the resistor R12 in cooperation with the capacitor C5, timing in 
accomplished so that the timer IC2 clocks out or completes its timing 
cycle and switches off, removing power from the solenoid 27. This normally 
lasts one second in operation. 
In FIG. 3 of the drawings this sequence is shown and is initiated by the 
leading edge of the pulse at 34. When that occurs, the signal for the 
solenoid 27 becomes positive as shown at the leading edge of the signal. 
That signal runs for the duration determined by the timing of the RC 
circuit just mentioned; that signal is terminated by the trailing edge of 
the pulse 34 which coincides with the trailing edge of the pulse 36. Of 
course, feedback or verification is accomplished by the leading edge of 
the pulse 38; that signal continues so long as the bolt is in the locked 
status; however, the one second interval is accomplished between the 
leading edge of the pulse 38 and the trailing edge 40 of the pulse 36 
where the pulse 36 goes negative. Another sequence of operation is also 
shown utilizing the timing chart of FIG. 3. The timing chart of FIG. 3 
shows a change in the position of the door which is transmitted by the DPS 
16. This is the positive going signal 42. When this signal is present, it 
provides the enable pulse to the timer IC1 which forms the positive going 
pulse 44. This signal causes operation of the solenoid valve 27, and 
additionally holds that sufficiently long that it has time to complete 
deadbolt locking. The signal does not need to persist and to that end, it 
has a short duration, approximately one second which is determined by the 
RC time constant of the selected components connected to the timer IC2. 
An additional sequence of operation is illustrated in the timing chart 
where the remote control unit is operated by depressing a switch 48. It is 
depressed momentarily to provide B+ to the remote unlock input, and that 
is delivered to the anode of the diode D5. That is coupled directly to the 
output of the solenoid 26 for unlocking. The input signal identified at 50 
and the solenoid output signal occur at the same instant at 52. This 
achieves pneumatic alteration of the bolt from the deadlock position, and 
that is sensed by the switch 25 which provides verification as represented 
in the timing chart by the state change at 54. This permits the door to be 
opened; it can be opened or left closed, but its state is determined by 
the DPS 16 which provides the output signal at 56 which is indicative of 
opening or closing. 
In the foregoing operations, the timing chart shows the two patterns at 60 
and 62 which are associated with lamps at the remote station. One can be 
omitted and the other can be relied upon for an indication. However, it is 
preferable to use two lamps so that one positively indicates the state of 
affairs continuously. To this end, when one lamp is on, the other lamp is 
off as identified in the timing patterns at 60 and 62. 
Several of the components shown in FIG. 2 have functions which have not 
been specifically delineated. The transistor T1 along with the associated 
circuitry serves as a voltage regulator which regulates the voltage level 
on the line 64. That line is input to several of the components to provide 
a proper or selected operating voltage for the components. The transistor 
T2 primarily responds with a switching function dependent on an input 
signal through the DPS 16; thus, when it operates, it provides an input 
signal to the second pin of the timing circuit IC1. That in turn forms a 
signal at the output on pin 4 which is coupled through the transistor T5. 
In addition, an input B+ from the DPS 16 is also provided to the base of 
the transistor T4, providing a switch function, and that in turn switches 
on the transistor T9 and that in turn causes conduction through the relay 
RY. When the transistor T9 conducts, relay operation is provided. 
The diodes D2 and D3 provide a clipping function to avoid negative 
overshoot on switching for the solenoid drive currents. Solenoids are 
primarily inductive; when provided with a step function input, they may 
ring and these two diodes provide clipping to prevent ringing. 
The device of the present invention is a control circuit which enables 
control of the locked door either subject to the key switch 24 or the 
remote switch 48. It is particularly useful in providing a positive 
interlock in the DPS 16 control operation only when the door is properly 
aligned with the door frame 11. Moreover, the lock includes the deadlock 
switch 25 which provides assurance that the deadlocking position has been 
achieved, thereby yielding a feedback signal which enables completion of 
operation. It is a system which can operate either with a single double 
acting pneumatic cylinder or with two separate single acting pneumatic 
cylinders. Recall as mentioned earlier that the bolt has three positions 
which are fully retracted, fully extended in the deadlock position, or 
extended in the slamlock position. In the intermediate position, the bolt 
is free to slide so that it can slide over the striker plate 13. 
While the foregoing is directed to the preferred embodiment, the scope is 
determined by the claims which follow: