Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS3622998 A
Publication typeGrant
Publication date23 Nov 1971
Filing date2 Mar 1970
Priority date2 Mar 1970
Publication numberUS 3622998 A, US 3622998A, US-A-3622998, US3622998 A, US3622998A
InventorsKortman Joe M, Schulein Joseph
Original AssigneeDutton Hayward H, Kortman Joe M, Schulein Joseph, Schulein Margaret A
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Remote control system with verification capability
US 3622998 A
Abstract  available in
Images(3)
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

I United States Patent [1113 622 998 [72] Inventors Joe M. Kortman; 3,472,965 1 6/1969 Blossom ..L 340/147X Joseph schumn both Vancouver wash Primary ExaminerDonald J. Yusko [21] 154% Attorney-Kolisch & Hartwell [22] Filed Mar. 2, 1970 [45] Patented Nov. 23, 1971 1 Assignees Bum"! y Tm the ABSTRACT: A system for operating actuators, such as elec- Tnms trically operable door locks, at one or more remote stations by Tmma; means of a control unit at a central station. A lock signal of 1 9 schuldnaMeraam A'schukini predetermined frequency is generated upon operation of a vamvel" wflsh- P interest mead! lock button on the control unit. The lock signal is supplied to the remote station via a main communication channel to deenergize power units on the doors and permit the spring- [54] WITH loaded door locks to lock. An indicator lamp is provided at the central station to verify the proper locking of the doors upon 4 Claims 4 Drawing reception of a return signal from the remote station. To open [52] US. Cl 340/1171 R, the doors, an unlock signal of another predetermined frequen- 343/225 cy is supplied to the remote station via the main communica- [51] lnt.Cl H041 9/00, tion channel line to energize the power units and overcome G08b 5/00 the spring forces on the locks. The unlock signal is initiated [50] F leld of Search 340/ l 7 1 upon operation of an unlock button on the central station con- 147, 408, 226; 343/225, 228 trol unit or by operation of an unlock button on a second control unit at the remote station. A signal of a third predeter- Rdemms Cited mined frequency is supplied upon operation of a night control UNITED STATES PATENTS button on the central station control unit to open a designated 3,371,316 2/1968 Johnson 340/171 door at the remote station used for authorized night entry.

MA/A/ Ame aw)?" REMOTE CONTROL SYSTEM WITH VERIFICATION CAPABILITY BACKGROUND OF THE INVENTION The present invention concerns a system for operating and monitoring the condition of electrically energizable devices at one or more remote stations from a control unit at a central station. A preferred embodiment of the system is described in conjunction with controlling electrically actuatable door locks.

Systems have been proposed in the prior art for automatically operating devices at remote stations by means of controls at a central station. Generally, it is desirable that such systems be fail-safe in the sense that power failure or system failure leaves the controlled elements in a preferred or safe position. Furthermore, it is desirable to provide indicator means in such a system for an operator to verify the correct operation of the system. Finally, it is desirable to provide means for an operator at a remote station to carry out independently certain control operations without compromising the security afforded by central station control.

Generally, the remote-central station control systems known in the prior art have omitted one or more of the above features and have not been characterized by good reliability. Furthermore, prior art systems are usually complex and so expensive that the cost of their use in other than the most sophisticated applications is prohibitive.

OBJECTS OF THE INVENTION Accordingly, it is an object of the invention to provide an improved and simplified system for operating electrically energizable devices at one or more remote stations by means of a control unit located at a central station.

It is another object of the invention to provide such a system which afiords positive verification of the state or condition of a remotely controlled device.

It is a further object of the invention to provide a system of the type described wherein verification errors are minimized.

A preferred embodiment, as described herein, is used in conjunction with locking and unlocking remote door locks which are electrically actuatable. The locks are of a type which are fail-safe, in the sense that on the removal of energizing power, the locks automatically lock. Signalers are provided at a central station in the system which transmit signals for locking and unlocking one or more locks. A signaler at a remote station where controlled locks are located transmits a signal to a receiver at the central station to indicate when the locks are locked. Means are provided at the central station which prevents the occurrence of a locked-condition indication unless the remote locks have in fact locked.

BRIEF DESCRIPTION OF THE DRAWINGS These and other objects of the invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a block diagram of a central control station employing the invention;

FIG. 2 is a block diagram of a remote station employing the invention;

FIG. 3 is a table showing the instantaneous conditions of various elements of the remote and central stations during operation of the system; and

FIG. 4 is a block diagram of a system which includes two remote stations designed in accordance with the invention.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings, the preferred embodiment of the invention is used in conjunction with an electrical locking system which includes a central station as shown in FIG. I and one or more remote stations, each comprising elements arranged as shown in FIG. 2. For purposes of explanation, the elements of the central and remote stations are shown in their normally deenergized conditions.

A main communication channel 10 interconnects the central station and each of the remote stations of the system. While only a single remote station is shown in the preferred embodiment, as many additional remote stations as are desired can be added to the system. Generators 12, 14, and 16 of the central station are selectively isolated from the main line by a relay-controlled switch 18 including an actuating winding 19 and a normally open contact 20 in the main line. Control buttons 22, 24 and 26 are provided having first terminals connected, respectively, to generators 12, 14, and 16; and second tenninals connected to a DC power supply 28. A common power circuit is provided from the control buttons to switch 18 including lines 30 and diodes 31, 32, and 33 poled to permit current flow as shown. Operation of any of the control buttons 22, 24, 26 closes its contacts providing power to the generator associated therewith, and simultaneously providing power to winding 19 to close contact 20.

All the generators are of conventional design. Generator I2 selectively provides a 730 cycle AC signal; generator 14 selectively provides a 400 cycle AC signal; and generator 16 selectively provides a 960 cycle AC signal. In the embodiment illustrated, a signal from generator 12 is employed to lock all doors at the remote station; generator 14 to unlock one of these doors for authorized night-entry purposes; and generator 16 to unlock all such doors. The manner in which signals from these generators effect operation of the locks at the remote station is explained hereinafter.

Line 35 connects the main channel 10 to an input of preamplifier 36, and lines 38 connect the output of the preamplifier to input terminals of a receiver 40 and a receiver 42. Receiver 40 is a frequency-selective amplifier designed to produce a positive DC output in response to receiving at its input a 960 cycle AC signal, and to produce a zero output in response to all other inputs. Receiver 42 is also a frequency-selective amplifier, designed to produce a positive DC output in response to a 1300 cycle input signal, and to produce a zero output in response to all other inputs.

Line 44 connects the output of receiver 40 to the B input terminal of a dual input gate 46, and line 48 connects the output of receiver 42 to the A input terminal of a dual-input gate 50. The A input terminal of gate 46 is connected to the input side of generator 12 via line 34 and diode 47, and the output of gate 46 is connected to the B input terminal of gate 50 by line 51. Line 54 connects the output ofgate 50 to one terminal of an indicator lamp 55, which has another terminal grounded.

Gate 46 is a conventional unit designed to produce a positive level or ONE output on closing of the switch actuated by control button 22 and, simultaneously, the absence of a positive DC signal at the B input. Gate 46 produces a low level or ZERO output in the absence of a signal at the A input or in response to a positive DC inhibit pulse at the B input. Once the output of gate 46 is set to a ONE level it will remain in that state until a ONE or inhibit signal is applied to the B input terminal.

Gate 50 is a conventional-type dual-input gate which functions somewhat differently than gate 46. The output of the gate is placed in a ONE state on ONE state voltages being placed simultaneously on both inputs. The output of the gate remains in a ONE state thereafter so long as a ONE state remains on the B input. In the absence of a ONE state on the B input, the output is in a ZERO state regardless of the condition of the A input.

With the output of gate 50 in a ONE state, lamp 55 is energized.

Referring now to FIG. 2, main channel 10 is shown connected to an input terminal of an amplifier 60. Lines 61, 62 connect the output of amplifier 60 to input terminals of receivers 66, 68, and 70. Amplifier 60 is a conventional unit and receivers 66, 68, and 70 are conventional frequencyselective amplifiers similar in design to receivers 40 and 42. Receiver 66 produces a positive DC output signal in response to receiving a 960 cycle AC input. Likewise, receiver 68 produces a positive DC output signal in response to receiving a 730 cycle AC input; a receiver 70 produces a positive DC output signal in response to receiving a 400 cycle AC input. Line 72 connects the output of receiver 66 to the A input terminal of a gate 76 which is substantially the same as gate 46, and line 73 connects the output of receiver 68 to the B or inhibit input terminal of gate 76. Line 73 also connects the output of receiver 68 to an input terminal of a conventional timer 77.

Timer 77 is a unit designed to produce a DC output pulse of fixed duration, beginning on removal of a positive DC input signal on line 73 from receiver 68. Line 63 connects the output of the timer through normally closed contacts 83 to an input terminal of a 1300 cycle AC generator 64. Line 65 returns the output of generator 64 tomain channel 10.

Line 74 connects the output of gate 76 to an input terminal of relay 80, relay 82, and relay 84. Line 75 connects the output of receiver 70 to the input terminal of relay 84. A diode 86 is provided in line 74 between relays 82 and 84 to block the output of receiver 70 from relays 80 and 82.

As shown by the dotted lines, a set of normally open contacts 8l are associated with relay 80. Normally closed contacts 83 are associated with relay 82. And normally open contacts 85 are associated with relay 84. When relay 80 is energized contacts 81 close and voltage is supplied from a source, not shown, via line 87 to a plurality of power units 88, each associated with a main door look at the remote station. When energized, the power units have sufficient force to overcome the force of spring members on the door locks and unlock the doors. However, when the power units are deenergized with the doors in a closed position, the spring-loaded locks move into their locked positions.

In similar fashion, the energization of relay 84 closes contacts 85 whereby voltage is supplied from a source, not shown, via line 89 to a power unit 90 associated with a door designated for night use at the remote station. Energization of relay 82 opens contacts 83 and interrupts the circuit between timer 77 and generator 64.

Controlswitch 91 is part of an outside control unit hidden near the remote station. One contact of switch 91 is connected to a DC source not shown, and line 92 connects the other contact of the switch to the input terminal of a generator 94. Generator 94, when energized, provides a 960 cycle AC output signal. The output of the generator is returned to main channel 10 via line 96, for a purpose to be explained.

Various operations of the system will now be explained in conjunction with the table shown in FIG. 3. The table shows the instantaneous state of various elements of the system during the various cycles of operation of the system. To lock the main doors, button 22 at the central station is depressed, whereby generator 12 is energized and provides a 730 cycle AC lock signal. Winding I9 is energized by actuation of button 22, and contact 20 of switch 18 closes to supply the lock signal to the remote station via main channel 10.

Closing of the switch associated with button 22 also supplies a ONE input to the A terminal of gate 46. Since there is then a ZERO on the B input of gate 46, the output of the gate has a ONE on it. The output of gate 50 is in a ZERO state since its A input is in a ZERO state. Therefore, lamp 55 is not energized.

The 730 cycle lock signal on the main channel is detected at the remote station by receiver 68 which provides a ONE input to the B input terminal of gate 76. Accordingly, the output of gate 76 is at a ZERO level and relays 80 and 82 are deenergized. With relay 80 in a deenergized condition, contacts 81 assume their normally open states and the power units for the main door locks are deenergized. Consequently, the springloaded locks move to their locked position.

At the same time, the ONE output of receiver 68 is supplied to timer 77, setting the latter. On removal of this ONE output from the input terminal of the timer the timer 77 produces a DC output pulse of fixed duration. Since relay 82 is deenergized, contacts 83 reside in a normally closed position and the output of timer 77 is supplied to generator 64. Generator 64 is actuated by the timer pulse and produces a 1300 cycle AC verification signal during the l-to'2-second duration of the timer pulse. The output of generator 64 is returned to the main channel and the central station where it is detected by receiver 42. The time interval afforded by timer 77 ensures proper and complete reception of a lock signal, and operation of the door locks, before a lock-verification signal can be returned to the central station. This is important in minimizing the chances for an error in the operation of the system.

In particular. the time interval mentioned assures that a lock-verification signal is not transmitted to line, or main channel, 10 while a lock signal is still on the line. It thus positively prevents these two types of signals from overlapping in time, and from interfering with one another. As an important consequence, a single line 10) only is required to handle both signals, and this greatly simplifies and reduces the cost of an installation employing the invention. The duration of an output signal of the timer is selected to ensure proper reception of a verification signal at the central station.

In response to the 1300 cycle verification signal, receiver 42 produces a ONE output which is supplied to the A input terminal of gate 50. Since the B input terminal of gate 50 is also at a ONE level, gate 50 produces a positive DC or ONE output which lights lamp 55 as an indication that the doors have properly locked. So long as the relays controlling the door locks are deenergized, the lamp remains lit.

To unlock the doors, button 26 at the central station is depressed by the operator to actuate generator 16 and provide a 960 cycle AC unlocking signal to the main channel. The unlocking signal is detected at the remote station by receiver 66 which produces a positive DC or ONE output in response thereto. The ONE output of receiver 66 is supplied to the A input terminal of gate 76. In the absence of a 730 cycle signal, the B input of gate 76 is at a ZERO level. Consequently, a ONE output is produced by gate 76 at its output, and supplied via line 74 to energize relays 80, 82, and 84. Energization of relay 80 closes contacts 81 and provides voltage to power units 88 which unlocks the main doors. Energization of relay 84 closes contacts and supplies voltage to unlock the night door. Energization of relay 82 opens contacts 83.

The 960 cycle unlock signal is also detected by receiver 40 at the central station which provides a ONE input to the B terminal of gate 46. As a consequence, the outputs of gates 46, 50 are placed at a ZERO level, and lamp 55 is deenergized to indicate that the doors are unlocked.

Operation of switch 91 at the remote station also provides a 960 cycle AC unlocking signal to the main channel which serves to unlock the main doors and night door in the manner just explained.

Control switch 91 is preferably hidden outside the remote station in a location known only to authorized persons. Accordingly, the switch can be utilized to provide an unlock signal for all the doors at the remote station without compromising the security of the system.

It will be noted that if, subsequent to transmission of a lock signal from generator 12, and prior to reception by receiver 42 of a verification signal, an unlock signal is transmitted by either of generators 16 or 94, lamp 55 will not light up. This is because receiver 40 will place an inhibit signal on the B input of gate 46, resulting in the application of a ZERO state voltage to the B input of gate 50. In order for the lamp to light, a proper verification signal must be received in receiver 42 subsequent to transmission of a lock signal by generator 12, without an intervening unlock signal. Because of this type action, good reliability is assured.

Should it be desired to admit a watchman through the night door during a time when all the doors are locked, this may be accomplished by depression of button 24 at the central station, in response to a phone call or some other suitable authorization signal. When button 24 is operated generator 14 is energized to provide a 400 cycle AC night unlock signal to the main channel which is detected by receiver 70. As long as button 24 is depressed, the output of receiver 70 is at a positive DC level. The positive DC signal from receiver 70 energizes relay 84 whereby contacts 85 are closed and the night door is unlocked. Upon release of button 24 the night door is relocked.

Alternatively, means may be provided to automatically operate button 24 for a predetermined entry period in response to a coded authorization signal sent by the watchman, to the central station via a conventional telephone circuit or by a separate communications circuit.

If desired, the central station of the invention can be used to control more than one remote stations. Such an arrangement is shown schematically in FIG. 4. In the embodiment shown, each remote station (which is substantially the same in construction as the remote station shown in FIG. 2) is connected to the central station (which is substantially the same in construction as the central station shown in FIG. 1) by a separate communication channel l0, A switch is provided at the central station for selection, by the operator, of the remote station or stations to be controlled upon a given control cycle. It is also within the scope of the invention to provide plural remote stations, each of which is responsive to a different set of control frequencies from the central station.

The system described is fail-safe in the sense that failure of the power supply for the main door power units or failure of the control circuitry will result in the opening of contacts 81 and 85 whereby the doors are locked. Furthermore, the system is secure in that a night door may be independently unlocked at each remote station to permit entry of an authorized person, in response to a proper signal received at the central station from the remote station. Finally, a separate, hidden control switch is provided at the remote station which may be used by authorized persons to unlock the doors, without compromising the security of the system.

While a preferred embodiment has been described in conjunction with a locking system, the control system of the invention may be used to actuate a variety of other devices at one or more remote stations. Likewise the use of AC generators or predetermined output frequency is not mandatory. Pulse coded lock and unlock signals generated by suitable means could be used as well.

lt is claimed and desired to secure by Letters Patent:

1. A system for controlling and monitoring from one location the state of an electrically energizable device at a remote location comprising a pair of signalers with one at said one location and the other at said remote location, said other signaler being operatively connected to said device and switching automatically to a signal-producing state following placement of said device in one state, and returning automatically to a nonsignal producing state with placement of said device in another state,

a pair of receivers, each for receiving a signal from a different signaler, with one receiver at said other location for receiving a signal from said one signaler, and the other receiver at said one location for receiving a signal from said other signaler, said one receiver being operatively connected to said device for effecting placement thereof in its said one state on the receiver receiving a signal from said one signaler,

an indicator at said one location having indicating and nonindicating states, and

interconnecting means at said one location operatively interconnecting said one signaler, said other receiver and said indicator effective to place the latter in its said indicating state on reception by said other receiver of a signal from said other signaler following transmission to said one receiver of a signal from said one signaler.

2. The system of claim 1 which further comprises a third signaler at said one location, and a third receiver at said remote location for receiving a signal from said third signaler and operatively connected to said device, said third receiver on receiving a signal from said third signaler effecting placement of said device in its said other state.

3. The system of claim 2, wherein said interconnecting means is operatively connected to said third signaler and is effectlve to inhibit placement of said indicator in its said indicating state in a case where transmission of a signal from said third signaler occurs subsequent to transmission of a signal from said one signaler and prior to reception of a signal by said other receiver.

4; The system of claim 3, wherein said device comprises part of a door lock mechanism which further includes a lock having locked and unlocked states, and said device when in its said one state places said lock in its said locked state.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3371316 *21 Jun 196327 Feb 1968Johnson McvoyRadio control system
US3472965 *11 Apr 196614 Oct 1969Ped IncTime-tone data transmission system
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3787868 *25 Jun 197122 Jan 1974J CampRemotely actuated release apparatus for ski bindings
US7046126 *11 Dec 200216 May 2006Omega Patents, L.L.C.Vehicle window control system for a vehicle having a data communications bus and associated methods
US706815331 Mar 200527 Jun 2006Omega Patents, L.L.C.Vehicle window control system for a vehicle having a data communications bus and associated methods
US716708330 Sep 200223 Jan 2007International Business Machines CorporationRecording and indicating the state of an apparatus remotely
US20030141986 *11 Dec 200231 Jul 2003Omega Patents, L.L.C.Vehicle window control system for a vehicle having a data communications bus and associated methods
US20040061604 *30 Sep 20021 Apr 2004Ibm CorporationRecording and indicating the state of an apparatus remotely
EP0614791A1 *8 Mar 199414 Sep 1994Thomson-CsfAntitheft device for motor vehicle
Classifications
U.S. Classification340/3.7, 340/5.5, 340/5.33
International ClassificationG07C9/00, G08C19/12
Cooperative ClassificationG07C2009/00761, G07C9/00182, G07C9/00103, G08C19/12
European ClassificationG07C9/00B8, G07C9/00E2, G08C19/12