US3656114A - Electronic lock arrangement having parallel coded input - Google Patents

Electronic lock arrangement having parallel coded input Download PDF

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US3656114A
US3656114A US820921A US3656114DA US3656114A US 3656114 A US3656114 A US 3656114A US 820921 A US820921 A US 820921A US 3656114D A US3656114D A US 3656114DA US 3656114 A US3656114 A US 3656114A
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parallel
alarm
lock release
signal
code
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Tore Gottfrid Hesselgren
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    • GPHYSICS
    • G07CHECKING-DEVICES
    • G07CTIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
    • G07C9/00Individual registration on entry or exit
    • G07C9/00174Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys
    • G07C9/00658Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated by passive electrical keys
    • G07C9/00674Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated by passive electrical keys with switch-buttons
    • G07C9/0069Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated by passive electrical keys with switch-buttons actuated in a predetermined sequence

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  • One type uses electro-mechanical step selectors with step-wise feeding in accordance with a predetermined set code, but this means the presence of a number of movable parts, the operations of which can be acoustically localized, thus simplifying a forcing thereof. They are also rather lumbering and not very well suited for automized manufacturing.
  • Relay chains with mechanical relays have also been suggested for the same or similar purposes, where the relays are to be actuated in a certain order for obtaining the desired result.
  • a change of code setting will in this'case be rather complicated as will be a neutralizing of the whole arrangement in connection with wrong handling.
  • Still another type of electronic code locks is previously known in principle including a number of code steps, which are serially actuated one after the other according to a predetermined code and where the last step when activated generates the control voltage which actuates the lock circuit and releases the lock.
  • FIG. 1 illustrates the principle design of the invention
  • FIGS. 2a and 2b together show a detailed circuit arrangement.
  • FIG. 1 a a represent the code pulse inputs and p the alarm input.
  • Vl V4 are flip-flops actuated by incoming code pulsesand the actuation of V2 V4 is accomplished via AND- gates GV2 GV4. All AND-gates feed directly and AND-gate GL5, which thus requires signals at all inputs for function.
  • gates Ga Gd which are connected to an OR-circuit, which is activated and causes alarm when output signals are obtained from anyone of the gates Ga-Gd.
  • the inputs of gates Ga Gd are connected to the code inputs, the alarm input and to the outputs of certain flip-flops.
  • the lock is so designed that for proper function a code pulse must arrive via cross wire field and proper push button, the gate Ga then maintaining rest condition. Code pulse a also switches the flip-flop V1, the gate Ga then being brought out of function and the first condition for lock release is met simultaneously with the preparation of gate GV2 via code ulse a.
  • the condition for lock release is that all flip-flops Vl V4 have been switched in proper consecutive order.
  • Thelock function is controlled by the AND-circuit GL5, which sends an output signal when all flip-flops havebeen switched and set in actuated condition.
  • the AND-circuit GLa is controlled only by the flip flop V4, which cannot be switched until all preceeding flip-flops in the chain have been actuated in proper order.
  • the flip-flops V1 V4. can be bistable and a time constant for the whole system is then introduced with coordinated resetting.
  • the time constant can suitably be regulated by the alarm pulse p.
  • FIGS. 2a and 2b illustrate the detailed circuitry of a preferred embodiment of the invention and FIG. 2b should be placed below FIG. 2a in order to obtain a properly combined arrangement.
  • the drawings include further a large number of coupling elements as resistors, capacitors and diodes, the object of which is to give the various electronic relay circuits proper potential levels at proper times. Most of these elements constitute no part of the invention and such 1 elements have not been referenced and will not be specially mentioned in the following specification, which only refers to elements, active as well as passive, and functions being of importance for the understanding of the invention.
  • FIG. 2a illustrates a cross wire field with a number of horizontal wires and associated push button contacts 0 9, and a number of vertical wires a d, each vertical wire being connected to a predetermined horizontal wire, for example at the marked junctions.
  • the illustrated code is 3,0,6,7.
  • the code pulses are passed via the vertical wires to the flip-flops, here represented by the transistor pairs TlT2,T3T4,T5T6,T7T8 and transistor combinations T9T10,T11T12,T13Tl4,T15T16 in FIG. 2b representing the gates Ga Gd in FIG. 1.
  • the feeding of these gates is made partly via terminals W1 W4 and partly via terminals Y1 Y4, the latter corresponding to the alarm input p in FIG. 1.
  • the outputs Q1 Q4 from these gates are connected to transistor T17, which represents the OR-circuit GLa in FIG. 1 causing alarm when actuated.
  • the gate outputs are also connected to the gates T9T10 T15Tl6 via terminals X and Z for neutralization, when necessary, of applied alarm pulses and via terminals R to the lock circuit, which has AND- function and here is represented by transistors T18 T20.
  • Switching of the flip-flops is obtained by the presence of a capacitor C in the base circuit of one transistor in each pair. This capacitor is charged by the applied code pulse and the as sociated base electrode receives the proper potential first at discharge of said capacitor, which happens at the end of the code pulse.
  • Pulse a which is applied to the first code step including flip-flop TlT2 and through the terminal W1 to gate T9T10 thereby short-circuiting the base of transistor T9 to ground and inhibiting the alarm (alarm pulse arrives simultaneously via terminal Y1).
  • Pulse a actuates the first flip-flop T1T2 so that transistor T1 is made conducting at discharge of capacitor C resulting in a pulse at terminal XlZ2 and this condition is then maintained which means inhibiting function at gate T9Tl0, i.e. transistor T9 short-circuits the base of transistor T10 thus preventing output signal at the Q1 output of the gate.
  • Output signals at terminals 0 are always negative inthe selected example.
  • An electronic code lock device comprising: lock release means comprising a plurality of multi-stable serially connected elements each element having a parallel input and a parallel output, said lock release means only being responsive to the application of code pulses to said parallel input in a predetermined sequential manner to generate a signal on each of the parallel outputs, each signal defining the state of a respective multi-state element, and said plurality of signals defining a lock release signal; and alarm actuating means having a plurality of parallel monitoring inputs each respectively coupled to said parallel outputs of each multi-stable element and sensing the state thereof, said alarm actuating means generating an alarm signal only in response to states of said multi-state elements indicative of the application of code pulses to said multi-stable element parallel inputs in a manner other than in said predetermined manner.
  • the device of claim 1 further including a lock release mechanism, said lock release mechanism being coupled to each of said parallel outputs of said multi-stable element, said lock release mechanism being responsive to said lock release signal.
  • said alarm actuating means includes a plurality of sampling gates having inputs coupled to selected parallel outputs of said multi-stable elements, each sampling gate further being coupled to a common alarm interrogation input, the coexistence at any sampling gate of an alarm interrogation signal and a state of a multi-stable element parallel output indicative of code pulse application in a manner other than in said predetermined manner effecting actuation of said sampling gate and generation of said alarm signal.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Burglar Alarm Systems (AREA)
  • Lock And Its Accessories (AREA)
  • Emergency Alarm Devices (AREA)

Abstract

An electronic lock arrangement is disclosed, the arrangement comprising a plurality of consecutively disposed code step circuits. Each circuit, when actuated by an input code pulse train, generates a parallel output, which outputs define a lock release output signal when the input code pulse train is received in proper predetermined order.

Description

I United States Patent 051 3,656,114 Hesselgren [451 Apr. 11, 1972 1 ELECTRONIC LOCK ARRANGEMENT 3,080,547 3/1963 Cooper ..340/164 HAVING PARALLEL CODED INPUT 3,327,290 6/1967 Eglish ..340/164 x 2,855,588 10/1958 Allen ..340/164 UX [72] i f gg' Bmnsvagen 3,046,526 7/1962 Scantlin ..340/164 3,100,389 8/1963 Noregaard ..340/164 UX [22] Filed: May 1, 1969 3,175,191 3/1965 Cohn........,. .....340/l64 [211 App] No 820 921 3,380,024 4/1968 Watkinson ..340/164 Primary Examiner-Harold I. Pitts [30] Foreign Application Priority Data Attorney-Holman & Stem M 7,1968 S d ..611 68 ay we 3/ 57 ABSTRACT [52] Cl "340/164! 340/167 340/274 An electronic lock arrangement is disclosed, the arrangement [5]] lat. Cl. ..H04g 3/02 comprising a m m of consecutively disposed code t Fleld ofSearch cuits Each circuit when actuated an i p d pulse train, generates a parallel output, which outputs define a lock [56] Reerences C'ted release output signal when the input code pulse train is UNITED STATES PATENTS received in proper predetermined order.
3,024,452 3/1962 Leonard ..340/274 3 Claims, 3Drawing Figures w 76 0 o o o (T v1 v2 v3 l'/ v4 evz ova ev4 L3 l l 1 1 l r 1 7 1 Go Gb Gc Lorm SHEET 1 BF 3 umu INVENTOR 776-, flan-a (new ATTORNEYS W I a PATENTEDAPR 1 1 I972 oer ELECTRONIC LOCK ARRANGEMENT HAVING PARALLEL CODED INPUT DESCRIPTION OF INVENTION have all been rather complicated and in lack of the desired security. One type uses electro-mechanical step selectors with step-wise feeding in accordance with a predetermined set code, but this means the presence of a number of movable parts, the operations of which can be acoustically localized, thus simplifying a forcing thereof. They are also rather lumbering and not very well suited for automized manufacturing.
, Relay chains with mechanical relays have also been suggested for the same or similar purposes, where the relays are to be actuated in a certain order for obtaining the desired result. A change of code setting will in this'case be rather complicated as will be a neutralizing of the whole arrangement in connection with wrong handling.
Still another type of electronic code locks is previously known in principle including a number of code steps, which are serially actuated one after the other according to a predetermined code and where the last step when activated generates the control voltage which actuates the lock circuit and releases the lock.
The invention will now be more closely described in connection with the accompanying drawings, which illustrate a practical embodiment of the invention and where 1 FIG. 1 illustrates the principle design of the invention and FIGS. 2a and 2b together show a detailed circuit arrangement. A
In FIG. 1 a a represent the code pulse inputs and p the alarm input. Vl V4 are flip-flops actuated by incoming code pulsesand the actuation of V2 V4 is accomplished via AND- gates GV2 GV4. All AND-gates feed directly and AND-gate GL5, which thus requires signals at all inputs for function. There are also a number of gates Ga Gd which are connected to an OR-circuit, which is activated and causes alarm when output signals are obtained from anyone of the gates Ga-Gd. The inputs of gates Ga Gd are connected to the code inputs, the alarm input and to the outputs of certain flip-flops.
The lock is so designed that for proper function a code pulse must arrive via cross wire field and proper push button, the gate Ga then maintaining rest condition. Code pulse a also switches the flip-flop V1, the gate Ga then being brought out of function and the first condition for lock release is met simultaneously with the preparation of gate GV2 via code ulse a.
p As flip-flop V1 is in actuated condition and gate GV2 prepared the gate will pass the succeeding code pulse b to flipflop V2, which then is switched. Code pulse b thus can inhibit the alarm pulse in the gate Gb simultaneously with its arrival to gate GV3 then being prepared. The function course is then repeated for consecutive pulses c and d. However, if a new pulse should appear at a after the receipt of pulse balarm is released via gate Gc, wherein no neutralizing of the alarm pulse is obtained in the absence of code pulse c.
Thus, the condition for lock release is that all flip-flops Vl V4 have been switched in proper consecutive order. Thelock function is controlled by the AND-circuit GL5, which sends an output signal when all flip-flops havebeen switched and set in actuated condition. Alternatively the AND-circuit GLa is controlled only by the flip flop V4, which cannot be switched until all preceeding flip-flops in the chain have been actuated in proper order.
The flip-flops V1 V4.can be bistable and a time constant for the whole system is then introduced with coordinated resetting. The time constant can suitably be regulated by the alarm pulse p.
FIGS. 2a and 2b illustrate the detailed circuitry of a preferred embodiment of the invention and FIG. 2b should be placed below FIG. 2a in order to obtain a properly combined arrangement. In order not to overload the drawings unnecessarily with connection wires terminals are shown in both Figures, the principle being that terminals with identical references are interconnected. The drawings include further a large number of coupling elements as resistors, capacitors and diodes, the object of which is to give the various electronic relay circuits proper potential levels at proper times. Most of these elements constitute no part of the invention and such 1 elements have not been referenced and will not be specially mentioned in the following specification, which only refers to elements, active as well as passive, and functions being of importance for the understanding of the invention.
FIG. 2a illustrates a cross wire field with a number of horizontal wires and associated push button contacts 0 9, and a number of vertical wires a d, each vertical wire being connected to a predetermined horizontal wire, for example at the marked junctions. As the lock can be released only by a consecutive pulse order a,b,c,d this means that the illustrated code is 3,0,6,7. This code can of course be easily changed by selecting other junctions. The code pulses are passed via the vertical wires to the flip-flops, here represented by the transistor pairs TlT2,T3T4,T5T6,T7T8 and transistor combinations T9T10,T11T12,T13Tl4,T15T16 in FIG. 2b representing the gates Ga Gd in FIG. 1. The feeding of these gates is made partly via terminals W1 W4 and partly via terminals Y1 Y4, the latter corresponding to the alarm input p in FIG. 1. The outputs Q1 Q4 from these gates are connected to transistor T17, which represents the OR-circuit GLa in FIG. 1 causing alarm when actuated. The gate outputs are also connected to the gates T9T10 T15Tl6 via terminals X and Z for neutralization, when necessary, of applied alarm pulses and via terminals R to the lock circuit, which has AND- function and here is represented by transistors T18 T20.
The previously mentioned switching of flip-flops T1T2 T7T8 will now be described more in detail in connection with FIG. 2a where it should be noted that switching occurs first at the termination of the applied code pulse.
Switching of the flip-flops is obtained by the presence of a capacitor C in the base circuit of one transistor in each pair. This capacitor is charged by the applied code pulse and the as sociated base electrode receives the proper potential first at discharge of said capacitor, which happens at the end of the code pulse.
Take for example .pulse a which is applied to the first code step including flip-flop TlT2 and through the terminal W1 to gate T9T10 thereby short-circuiting the base of transistor T9 to ground and inhibiting the alarm (alarm pulse arrives simultaneously via terminal Y1). Pulse a actuates the first flip-flop T1T2 so that transistor T1 is made conducting at discharge of capacitor C resulting in a pulse at terminal XlZ2 and this condition is then maintained which means inhibiting function at gate T9Tl0, i.e. transistor T9 short-circuits the base of transistor T10 thus preventing output signal at the Q1 output of the gate. Output signals at terminals 0 are always negative inthe selected example.
At arrival of code pulse a the base of transistor T1 goes negative thus making Tl conducting and as a result thereof also making T2 conducting. A special potential condition is then established by aid of resistors r which constitute a potential divider andcorrespond to the AND-gates GV2 GV4 in FIG. 1. This established potential condition makes then the proper function possible at arrival of the next code pulse b.
When code pulse b is applied to next. flip-flop the condition thereof will be influenced first at the termination of the pulse when a discharge occurs via the lower resistor r and transistor tial on terminals Q1 O4 is obtained when one or more of transistors Tl0,T12, T14 or T16 are made conducting and this happens only in connection with improper handling of the lock, i.e. wrong order between the input code pulses.
lclaim: 1. An electronic code lock device comprising: lock release means comprising a plurality of multi-stable serially connected elements each element having a parallel input and a parallel output, said lock release means only being responsive to the application of code pulses to said parallel input in a predetermined sequential manner to generate a signal on each of the parallel outputs, each signal defining the state of a respective multi-state element, and said plurality of signals defining a lock release signal; and alarm actuating means having a plurality of parallel monitoring inputs each respectively coupled to said parallel outputs of each multi-stable element and sensing the state thereof, said alarm actuating means generating an alarm signal only in response to states of said multi-state elements indicative of the application of code pulses to said multi-stable element parallel inputs in a manner other than in said predetermined manner.
2. The device of claim 1, further including a lock release mechanism, said lock release mechanism being coupled to each of said parallel outputs of said multi-stable element, said lock release mechanism being responsive to said lock release signal.
3. The device of claim 1, wherein said alarm actuating means includes a plurality of sampling gates having inputs coupled to selected parallel outputs of said multi-stable elements, each sampling gate further being coupled to a common alarm interrogation input, the coexistence at any sampling gate of an alarm interrogation signal and a state of a multi-stable element parallel output indicative of code pulse application in a manner other than in said predetermined manner effecting actuation of said sampling gate and generation of said alarm signal.
April 11, 1972 Patent No 3 656 11-14 I Dated Tore Gottfrid Hesselgren Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:
In the grant (only) insert the attached sheet:
Signed and sealed this 6th day of March 1973.
(SEAL) Attest;
EDWARD MJ LIYICIIER ,.IR. ROBERT GOTTSCHALK Attest'ing Officer Commissioner of Patents FORM PC1-1050 (10-69 USCOMM-DC 60315-1 69 i U Sv GOVERNMENT PRINYING OFFICE (969 0-365-334.

Claims (3)

1. An electronic code lock device comprising: lock release means comprising a plurality of multi-stable serially connected elements each element having a parallel input and a parallel output, said lock release means only being responsive to the application of code pulses to said parallel input in a predetermined sequential manner to generate a signal on each of the parallel outputs, each signal defining the state of a respective multi-state element, and said plurality of signals defining a lock release signal; and alarm actuating means having a plurality of parallel monitoring inputs each respectively coupled to said parallel outputs of each multi-stable element and sensing the state thereof, said alarm actuating means generating an alarm signal only in response to states of said multi-state elements indicative of the application of code pulses to said multi-stable element parallel inputs in a manner other than in said predetermined manner.
2. The device of claim 1, further including a lock release mechanism, said lock release mechanism being coupled to each of said parallel outputs of said multi-stable element, said lock release mechanism being responsive to said lock release signal.
3. The device of claim 1, wherein said alarm actuating means includes a plurality of sampling gates having inputs coupled to selected parallel outputs of said multi-stable elements, each sampling gate further being coupled to a common alarm interrogation input, the coexistence at any sampling gate of an alarm interrogation signal and a state of a multi-stable element parallel output indicative of code pulse application in a manner other than in said predetermined manner effecting actuation of said sampling gate and generation of said alarm signal.
US820921A 1968-05-07 1969-05-01 Electronic lock arrangement having parallel coded input Expired - Lifetime US3656114A (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3735381A (en) * 1971-06-01 1973-05-22 E Zadig Testing apparatus for selectively enabling controlled equipment
US3805246A (en) * 1972-05-08 1974-04-16 Univ Notra Dame Du Lac Coded access device
FR2396465A1 (en) * 1977-06-27 1979-01-26 Wulf Francis De Coded electronic lock switch - uses electronic logic circuits and six digit code from possible twelve digits
US4494114A (en) * 1983-12-05 1985-01-15 International Electronic Technology Corp. Security arrangement for and method of rendering microprocessor-controlled electronic equipment inoperative after occurrence of disabling event
TWI403634B (en) * 2010-06-18 2013-08-01 Mao Jung Fu Structure and Method of Password Lock for Combination of Photoelectric Switch and Silicon Control Rectifier and Logic Gate
TWI412651B (en) * 2010-06-18 2013-10-21 Mao Jung Fu The key to trigger the structure and method of the code lock of silicon - controlled rectifier and logic gate

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2855588A (en) * 1954-09-15 1958-10-07 Harry W Allen Combination lock and burglar alarm
US3024452A (en) * 1958-08-22 1962-03-06 Itt Multi-digit electrical door lock
US3046526A (en) * 1957-09-30 1962-07-24 scantlin
US3080547A (en) * 1958-11-03 1963-03-05 Motorola Inc Selective calling apparatus
US3100389A (en) * 1960-06-30 1963-08-13 Card Key System Inc Security booth
US3175191A (en) * 1960-01-14 1965-03-23 Motorola Inc Binary code signalling system having a binary counter at the receiver responsive to a selected code
US3327290A (en) * 1963-03-25 1967-06-20 Amp Inc Dial sequence detector
US3380024A (en) * 1964-04-16 1968-04-23 Northern Electric Co Multi-digit electrical combination lock

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2855588A (en) * 1954-09-15 1958-10-07 Harry W Allen Combination lock and burglar alarm
US3046526A (en) * 1957-09-30 1962-07-24 scantlin
US3024452A (en) * 1958-08-22 1962-03-06 Itt Multi-digit electrical door lock
US3080547A (en) * 1958-11-03 1963-03-05 Motorola Inc Selective calling apparatus
US3175191A (en) * 1960-01-14 1965-03-23 Motorola Inc Binary code signalling system having a binary counter at the receiver responsive to a selected code
US3100389A (en) * 1960-06-30 1963-08-13 Card Key System Inc Security booth
US3327290A (en) * 1963-03-25 1967-06-20 Amp Inc Dial sequence detector
US3380024A (en) * 1964-04-16 1968-04-23 Northern Electric Co Multi-digit electrical combination lock

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3735381A (en) * 1971-06-01 1973-05-22 E Zadig Testing apparatus for selectively enabling controlled equipment
US3805246A (en) * 1972-05-08 1974-04-16 Univ Notra Dame Du Lac Coded access device
FR2396465A1 (en) * 1977-06-27 1979-01-26 Wulf Francis De Coded electronic lock switch - uses electronic logic circuits and six digit code from possible twelve digits
US4494114A (en) * 1983-12-05 1985-01-15 International Electronic Technology Corp. Security arrangement for and method of rendering microprocessor-controlled electronic equipment inoperative after occurrence of disabling event
TWI403634B (en) * 2010-06-18 2013-08-01 Mao Jung Fu Structure and Method of Password Lock for Combination of Photoelectric Switch and Silicon Control Rectifier and Logic Gate
TWI412651B (en) * 2010-06-18 2013-10-21 Mao Jung Fu The key to trigger the structure and method of the code lock of silicon - controlled rectifier and logic gate

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DE1924875A1 (en) 1969-12-11
GB1269365A (en) 1972-04-06
JPS522359B1 (en) 1977-01-21
SE309924B (en) 1969-04-08

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