WO1986000364A1 - Lock working with magnetic mechanisms and coded keycard adapted thereto - Google Patents

Lock working with magnetic mechanisms and coded keycard adapted thereto Download PDF

Info

Publication number
WO1986000364A1
WO1986000364A1 PCT/EP1985/000310 EP8500310W WO8600364A1 WO 1986000364 A1 WO1986000364 A1 WO 1986000364A1 EP 8500310 W EP8500310 W EP 8500310W WO 8600364 A1 WO8600364 A1 WO 8600364A1
Authority
WO
WIPO (PCT)
Prior art keywords
lock
holes
plate
key
coding
Prior art date
Application number
PCT/EP1985/000310
Other languages
German (de)
French (fr)
Inventor
Bernhard Hüster
Uwe Urban
Christian Kaiser
Original Assignee
Deutsche Gerätebau Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to DE19843423714 priority Critical patent/DE3423714C1/en
Priority to DEP3423714.3 priority
Priority to DE19843435030 priority patent/DE3435030A1/en
Priority to DEP3435030.6 priority
Application filed by Deutsche Gerätebau Gmbh filed Critical Deutsche Gerätebau Gmbh
Publication of WO1986000364A1 publication Critical patent/WO1986000364A1/en

Links

Classifications

    • 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 entry or exit registers
    • 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
    • G07C9/00722Electronically 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 magnetic components, e.g. magnets, magnetic strips, metallic inserts
    • G07C9/00738Electronically 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 magnetic components, e.g. magnets, magnetic strips, metallic inserts sensed by Hall effect devices
    • GPHYSICS
    • G06COMPUTING; CALCULATING; COUNTING
    • G06KRECOGNITION OF DATA; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K7/00Methods or arrangements for sensing record carriers, e.g. for reading patterns
    • G06K7/08Methods or arrangements for sensing record carriers, e.g. for reading patterns by means detecting the change of an electrostatic or magnetic field, e.g. by detecting change of capacitance between electrodes
    • G06K7/082Methods or arrangements for sensing record carriers, e.g. for reading patterns by means detecting the change of an electrostatic or magnetic field, e.g. by detecting change of capacitance between electrodes using inductive or magnetic sensors
    • G06K7/087Methods or arrangements for sensing record carriers, e.g. for reading patterns by means detecting the change of an electrostatic or magnetic field, e.g. by detecting change of capacitance between electrodes using inductive or magnetic sensors flux-sensitive, e.g. magnetic, detectors

Abstract

In order to make invisible from the outside the coding of a keycard having magnetically readable information points and to prevent copying or modifying without destruction, while authorizing the reading thereof without moving parts, there is provided a plate (3) covered on both sides with plates (1, 2) of non-magnetizable material in the introduction direction with a plurality of cut-out holes (4) interarranged according to a key system for the magnetic reading and identification. The plate is made either of magnetizable material or of non-magnetizable material, the holes being in this case filled with a ferromagnetic substance (3a) according to a predetermined coding. To enable the introduction of the right side of the keycard into the lock, the edges of both covering plates are secured to each other in the plane of one of the covering plates and form on a front side a mouthpiece (7) of special shape. To each row of holes there is adjoined a reading head comprising a permanent magnet (9) directed to the rows of holes, of which the magnetic field lines are modified according to the introduction position of the keycard into the lock by means of the change between the air and the metal. This results in sudden modifications of the magnetic induction which is transformed by a measurement value converter (6) like a field plate into electric control and count pulses before it is supplied to an evaluation circuit.

Description

operating with magnetic means lock with associated suitably coded key card

The invention relates to a working magnetic means lock with corresponding, suitably coded key card, in which the in the direction of insertion in rows extending coding is partially formed of a magnetizable metal, which is invisibly embedded on both sides from the outside, each information points row containing the lock side, a read head is assigned, which consists of the plug-in plane for the key card adjacent a perpendicular thereto aligned permanent magnet and a with this flußrichtungsbezogen arranged in series magnetically sensitive semiconductor whose transformed output signals with a lock side stored, fixed, predetermined reference value coding are comparable in electrical voltages and in accordance serve with the key-side coding for unlocking or release of the lock. Such characteristics key systems are used to prevent the use of particular technical devices or release a certain group of people using the characteristic key as identification means. Fields of application are therefore Warenabgabe- equipment, fluid dispensing devices, öffnungseinrich- refunds for doors and barriers or the operation of machinery and vehicles.

For such institutions varied passkey systems are known.

In addition to the conventional key systems where passkey of metal are used, which bring about a mechanical or electro-mechanical release because of their shape, passkey systems are known in which rectangular plug made of plastic or plastic-embedded metal foils are made, the inductively, capacitively, optically by light - or infrared beam sensors are sampled. A typical example is identification cards according to DE-B 29 20 012 in which the front and rear side is covered with foil.

From DE-A 23 09 658 and DE-A 33 15 204 magnetic media are known in the form of a check card with laminated or embedded magnetic strip and aufmodelliertem magnetic code that is read or recorded by a magnetic head. The magnetic strips of such magnetic cards are relatively thin, which over time has the gradual loss of the recorded information about the episode.

It is known from DE-B 19 31 536, on a support plate of identification cards with surface patterns sprayed ferromagnetic material with an opaque and electrically non-detectable material, or by mixing or overlap to make it invisible.

In one with a key-operated lock, it is known from DE-B 29 33 453, to provide a key body of rectangular cross section made of non-magnetic material having upper and lower Codierstücken from soft-magnetic material and to introduce for actuating the lock of the key body in a reading head , the two magnets of annular flux-conducting and, arranged in an air gap of the flux conducting pieces Hall generator consists. During insertion of the bowl body, an asymmetrical with respect to the Hall generator magnetic shunt is formed by the central of the flux-conducting and the magnetic Limited opening of the yoke, wherein the position of the respective shunt with respect to the Hall generator controls the direction of the magnetic flux therethrough and the respective defined code number of the associated information center. The Hall generator is in this case once passes through a direction, in the other in the opposite direction from the magnetic flux.

The preparation of this known lock / key system, is connected with considerable expenditure in both the design of the key body and in the evaluation circuit.

A card-shaped key, which consist of three layers, comprising the middle layer of the encoding serving holes and which is covered outwards by layers which can not be seen, the coding are known from GB-A 21 27 4.79 and DE-A 24 61 908.. In the former document for reading the coding infrared radiation is used. Accordingly, the middle layer is opaque to infrared radiation, and may for example be formed by a perforated metal foil. On both sides of the. Insertion slot each one are each

Row of holes associated infrared emitter and infrared receiver. The infrared receiver register the rows provided in the middle layer holes each on passage of a hole between the transmitter and receiver during the insertion of Schlüsseikarte in the lock.

In DE-A 24 61 908, the scanning of the coding after completion of insertion of the card key carried by a predetermined pattern of probes that correspond in size and position to the pattern of the metal points of the holes in the card, "serve as the sensor small, cylindrical, cup-shaped blocks made of ferrous material such as iron compounds existing pot cores each having windings which act as primary and secondary windings of an iron core transformer and produce varying degrees of output signals depending on the presence or absence of a metal point. Scanning is thus inductive and static.

The scanning of the coding of this known lock / key system requires an extremely high circuit complexity, since in this statically operating lock / key system, a separate iron core transformer must be assigned to an associated electrical sensing circuit each hole or each magnetically readable information center of the key card. This effort will increase to the extent that such information points are provided in number to the key card. A lock / key system of the type mentioned above is addressed in the US-A 38 96 292nd However, the lock / key system of this type known works also static, meaning it can Auslδseschaltung only queried and the lock will not be released in fits of established key card when the key card has taken its inserted position and thus a switch has been closed.

In this known lock / key system embedded in plastic inserts of magnetizable metal. In this case, no metallic insert is provided in a row, which is detected by one of two existing, responsive to the Hall effect magnetic sensitive semiconductor. This number represents the one of two logic states for the evaluated in the trigger circuit criterion whether the inserted into the lock key card is a fitting for the lock, or a counterfeit, for example, all of magnetizable metal existing key card.

The invention has for its object to provide a lock / key system according to the manner of a passkey system of the aforementioned type, which easily the advantages of high strength, an outside covered, not lost continuous even .if frequent use and will not be duplicated or variable coding at connects manufacturability by sheet metal working machines, with the advantage of a serial reading of the coding. This object is inventively achieved in that the encoding by punching of holes is produced in an existing of a magnetizable metal plate, that the hole pattern is designed so that during the insertion of the key card for enabling a serial reading of the encoding clock pulses can be derived, and that the magnetically sensitive semiconductor is formed as a field plate and each row of holes is associated with a reading head.

The key-side coding is determined here by the arrangement of the rows of holes extending in the key card itself. These holes are arranged in each row within a preferably consisting entirely of a magnetizable metal middle plate for a passkey system at specified intervals and certain number to each other. Compared to deposits of magnetizable metal according to the US-A 38 96 292 provides a known hole-matrix within a group consisting of a magnetizable metal plate having a large number of different combinations and therefore a high level of encryption.

In the magnetic reading out of the hole pattern, the metal between two respective holes forms a low magnetic resistance, whereas on insertion of the key card into the lock, the transition between the metal face and a hole causes a change in the magnetic field line profile and thus a sudden change of the magnetic induction, by Meßwertumformung can be evaluated as electric count signals in the penetrated by the magnetic field of the permanent magnet field plate. An intense Feldliniendurchfluß by the field plate is then obtained, if this is in the corresponding the N-pole of the permanent magnet pole piece disposed with the interposition of a support, for example, glued on.

Such field plates are subject to longitudinal Hall effect or Gaußeffekt. The continuous in such semiconductors, charge carriers are deflected laterally by the action of the transverse magnetic field, wherein the path of the carriers extend with increasing magnetic field and the electrical resistance in the field plate thereby increased. Thereby regenerated electric count signals of the evaluation circuit are then fed.

To insert the keycard page correctly into the lock, this has an asymmetric longitudinal cross section. For this purpose, one of the foraminous plate covering outer plates to a correspondingly abgebördelten the thickness of the middle plate edge which is fixedly connected to the edge of the other plate. Here, the edge abgebördelte z-shaped and connected to ebeπflächig trained edge of the other covering plate, between the metal plate picking up, firmly.

In a further embodiment of the invention, one of the rows of holes is fully occupied with arranged at equidistant intervals holes which form an additional clock track. Regardless of the speed and uniformity with which a user inserts the key card in the insertion of the castle, is scanned at each defined by the clock track time point the corresponding column of the row on information points during the insertion of the key card and the key-side coding in the lock side evaluation or identification circuit compared to the abgespeicher- th there fixed setpoint coding. If they match the codes in the key card and in the evaluation circuit, the device can be, should be created to access, open, or set in motion.

A variant consists in that the plate, the information centers containing consists of non-magnetizable material and disposed a plurality of rows, comprising holes obtained by punching, which are filled in accordance with the predetermined coding of ferromagnetic material connected to said arranged in the lock write head upon insertion of the key card into the lock magnetically cooperates.

Embedding flux-conducting ferromagnetic material in the key body of non-magnetizable material is known per se from DE-A 31 44 616th The distances between the individual information locations of an information track are equal in this known key body. The quality of the individual information points is represented by different magnetic flux-conducting resistance or flux deflectors are used with modulating ehern magnetic resistance and assigned them Flußleitbleche forming a magnetic shunt. The production of the insertable in a recess of the key code elements is very complicated in this known type, because the different code values ​​embodying flux deflectors and Flußleitbleche milled, have to be stamped and glued. In code elements coding for a high-order code a sandwich-like composition is required.

When using flux-conducting each with a different magnetic resistance difference Liehe accordingly can be used ferromagnetic materials, to mold and process, in order to obtain the desired coding. This brings a high manufacturing effort.

In the description of the embodiments explained in more detail with a key card to be operated lock according to the invention are shown in the drawings. Show it

Figure 1 shows a cross section through the key card along line II in Figure 3;

Figure 2 shows the lock side opening for inserting the key card;

Forming a plan view of the key card;

Figure 4 a cross section through the inserted into the lock key card with a row of holes associated read head during passage of the magnetic field through the metal plate of the Schlüsseikarte between two holes;

Figure 5 a cross-section corresponding to Figure 4 during the passage of the magnetic field through one of the holes in the key card. Figure 6 a cross section through the key card in an enlarged scale along the line II in Figure 3 according to a second embodiment;

Figure 7 a cross-section corresponding to another embodiment.

As the pictures 1 and 3 show, there is a key card consists essentially of a plate 3 made of metal having a plurality of extending in the insertion direction of the card key rows of each other according to a key system-level holes 4. By the number of the holes and the distances between the holes of each row of holes set the encoding of the key card in relation to the predetermined lock side coding.

In the design variant according BIId 6, the plate 3 of non-magnetizable material, the holes provided in said plate are filled with a ferromagnetic material. In Figure 6 punched circular metal discs are inserted into the holes. As Figure 7 shows, the holes may be additionally filled in with 4 iron powder 3a, it being expedient to cover the holes on both sides with magnetically permeable binder.

On both sides of the plate 3 of disks 1 and 2 is covered from non-magnetizable material, whereby the hole pattern is invisible out to the outside. A covering panel 1 has a corresponding to the thickness of the plate 3 abgebördelten, z-shaped edge which forms with the planar edge of the plate 2 has a frame 5 and is fixedly connected by inserting the plate 3 to the edge of the plate. 2 This results in longitudinal cross section of an asymmetric profile of the key card, which matches the profile of the lock-side insertion. 8 In order to correct side introduction into the lock, the key card at one end face is provided with a mouthpiece 7, wherein the inserting of the key card marked into the lock through a side facing the mouthpiece 7 arrow.

Each row of holes is associated with a reading head, consisting of a permanent magnet 9, and a transducer. 6 The permanent magnet 9 is oriented so that its emerging from the one pole shoe the magnetic field penetrates a portion of the slot behind the lock-side insertion opening 8 before it re-enters at the other pole piece.

When transducer 6, a pole piece to the one applied so-called field plate is used, which is a magnetically-controllable resistor, the ability to influence based on the Hall effect or longitudinal Gaußeffekt. The passing through the semiconductor charge carriers are deflected laterally by the action of the transverse magnetic field, wherein the path of the carriers extend with increasing magnetic field. Upon insertion of the key card in the lock side opening 8 passes alternately a hole, ie air, and located between two holes of the metal plate 3 in the leakage flux of the permanent magnet. As soon as and as long as metal is moved past the field plate, a signal is generated by deflection of the bias field by means of the passing metal area between two holes, as indicating Figure 4 symbolically. Here, the exiting stray flux is amplified and the field plate resistance increases. However, once the field plate is crossed by a hole 4 of the plate 3, the exiting flux leakage is reduced and softened, as indicated in Figure 5, adjacent to the to the hole

Metal areas with the consequence that the field plate resistance decreases.

Each exchange between air and metal has an abrupt change of the magnetic flux through the effective as a transducer 6 field plate result, whereby a current surge is generated, which is fed as counting pulse via lines R a not shown in the drawing evaluation circuit.

The logic of the evaluation circuit is chosen so that irrespective of the speed and the uniformity with which the card key is inserted into the lock, always a correlation is also provided between the individual rows of holes. Suppose it is in the key card with the hole pattern as shown in Figure 3 to a matching to the corresponding lock key card, the coding of the lock side, fixed predetermined coding matches if during insertion of the key card in the lock last all four transducers holes in See Figure 3 on the section line II following line. When inserting the key card, the points at which no holes are provided, information gaps that manifest themselves by failure of one count form. The left row of holes in the plan view of the key card in accordance with Figure 3 is completely interspersed with holes be. These holes generate clock signals which are to be generated depending on the position of the key card in the lock one, two or three counts in the other three rows.

Clock and counts can be stored in the evaluating circuit, to the key card has been fully inserted into the lock side opening. 8 The then made comparison with the lock-side coding then leads to an actuation of the lock, for example, open to one or starting up the device when coincidence of the codes has been found ..

The invention is not limited to the illustrated embodiment. Thus embodiments are conceivable in which not a rod-shaped, but a ring-shaped permanent magnet is provided, which has a width of the insertion slot corresponding air gap. The magnetic field concentrates on the cross-section of the air gap. Instead of holes, the metal plate may be provided with narrow, transverse to the insertion slots, whereby a very precise response of the transducer can be achieved, since rectilinear edges between metal and air are present, at which abruptly changes during the movement of the key card, the magnetic flux of force ,

Claims

Ü patent claims CHE
operating with magnetic means lock with corresponding, suitably coded key card, in which the rows extending in the insertion direction coding is partially formed of a magnetizable metal, which is invisibly embedded on both sides from the outside, each information points is assigned row containing the lock side, a reading head at the plug-in plane for the key card is adjacent a perpendicular thereto aligned permanent magnet and a with this flußrichtungsbezogen arranged in series magnetically sensitive semiconductor whose transformed output signals with a lock side stored, fixed, predetermined reference value coding are comparable in electrical voltages and in accordance with the key-side coding for unlocking serve or release of the lock, characterized in that the encoding by punching of holes (4) in an existing of a magnetizable metal plate (3 is generated) that the hole pattern is designed so that during the insertion of the key card for enabling a serial reading of the encoding clock pulses can be derived, and that the magnetically sensitive semiconductor is formed as a field plate (6) and each row of holes is associated with a reading head.
2. operating with magnetic means lock with corresponding, suitably coded key card, in which the rows extending in the insertion direction coding is partially formed of a magnetizable metal, which is invisibly embedded on both sides from the outside, each information points is assigned row containing the lock side, a read head, the consists of the plug-in plane for the key card adjacent a perpendicular thereto aligned permanent magnet and a with this flußrichtungsbezogen arranged in series magnetically sensitive semiconductor whose transformed output signals with a lock side stored, fixed, predetermined reference value coding are comparable in electrical voltages and in accordance with the schlusselseitigen coding serve for unlocking or release of the lock, characterized in that the plate bodies containing the information (3) consists of non-magnetizable material and a e arranged plurality of rows, obtained by punching out holes (4) which are filled in accordance with the predetermined coding with a ferromagnetic material which interacts magnetically with the lock arranged in the read head during the insertion of the key card in the lock.
3. lock / key system according to claim 1, ABy in that the holes (4) having plate
(3) in its thickness made entirely of a magnetizable metal.
4. lock / key system according to claim 3, characterized in that the holes (4) having plate
(3) external covering panels (1, 2) consist of non-magnetizable material and one of these plates (1 or 2) a corresponding to the thickness of the holes
(4) has possessing plate (3) abgebördelten edge which is fixedly connected to the edge of the other plate (2 or 1).
5. lock / key system according to claim 4, characterized in that the abgebördelte edge is formed z-shaped and has a frame with the planar edge of the other covering plate (5), in having the said holes (4) plate ( 3) can be inserted.
is 6. lock / key system according to claim 1 or 2, characterized in that the field plate (6) to the corresponding to the N-pole of pole piece of the permanent magnet (9) with the interposition of a support disposed, for example glued.
7. lock / key system according to claim 1 or 2, characterized in that one of the rows of holes is fully occupied with arranged at equidistant intervals holes as additional clock track.
8. lock / key system according to claim 2, characterized in that the holes (4) are filled with punched, circular metal discs.
9 are lock / key system according to claim 2, characterized in that the holes (4) filled with iron powder and covered on both sides with a magnetically permeable binder.
PCT/EP1985/000310 1984-06-27 1985-06-26 Lock working with magnetic mechanisms and coded keycard adapted thereto WO1986000364A1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
DE19843423714 DE3423714C1 (en) 1984-06-27 1984-06-27 Lock working by magnetic means and having an associated suitably coded key card
DEP3423714.3 1984-06-27
DE19843435030 DE3435030A1 (en) 1984-09-24 1984-09-24 Lock working with magnetic means and having an associated fitting key card
DEP3435030.6 1984-09-24

Publications (1)

Publication Number Publication Date
WO1986000364A1 true WO1986000364A1 (en) 1986-01-16

Family

ID=25822453

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1985/000310 WO1986000364A1 (en) 1984-06-27 1985-06-26 Lock working with magnetic mechanisms and coded keycard adapted thereto

Country Status (2)

Country Link
EP (1) EP0188476A1 (en)
WO (1) WO1986000364A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0569816A2 (en) * 1992-05-11 1993-11-18 Nobuyuki Ainoya Aggregation system for sales of immaterials in the form of signals
DE102016013283A1 (en) * 2016-11-08 2018-05-09 Liebherr-Hausgeräte Lienz Gmbh The refrigerator and / or freezer

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1471893A (en) * 1965-03-24 1967-03-03 Siemens Ag Carrier information exploration galvanomagnetic comprising a scanning member
DE2154114A1 (en) * 1971-10-29 1973-05-10 Ddm Hopt Schuler Fa Data recovery system
US3852572A (en) * 1972-01-03 1974-12-03 Sodeco Compteurs De Geneve Identity card reader
US3896292A (en) * 1973-06-18 1975-07-22 Michael May Hall effect position coded card detector

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1471893A (en) * 1965-03-24 1967-03-03 Siemens Ag Carrier information exploration galvanomagnetic comprising a scanning member
DE2154114A1 (en) * 1971-10-29 1973-05-10 Ddm Hopt Schuler Fa Data recovery system
US3852572A (en) * 1972-01-03 1974-12-03 Sodeco Compteurs De Geneve Identity card reader
US3896292A (en) * 1973-06-18 1975-07-22 Michael May Hall effect position coded card detector

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0569816A2 (en) * 1992-05-11 1993-11-18 Nobuyuki Ainoya Aggregation system for sales of immaterials in the form of signals
EP0569816A3 (en) * 1992-05-11 1995-02-08 Nobuyuki Ainoya Aggregation system for sales of immaterials in the form of signals.
DE102016013283A1 (en) * 2016-11-08 2018-05-09 Liebherr-Hausgeräte Lienz Gmbh The refrigerator and / or freezer

Also Published As

Publication number Publication date
EP0188476A1 (en) 1986-07-30

Similar Documents

Publication Publication Date Title
US3221304A (en) Electronic identification system employing a data bearing identification card
US3419710A (en) Magnetic card reader having sequential indicia sensing means
US6481623B1 (en) Card reader for transmission of data by sound
AU715989B2 (en) Article inventory tracking and control system
EP0656607B1 (en) Object to be checked for authenticity and a method for manufacturing the same
DE19719905B9 (en) Electronic vernier caliper with an inductive low-power position transducer
US3733862A (en) Combined mechanical and photoelectric lock
US8686869B2 (en) Alignment-related operation and position sensing of electronic and other locks and other objects
US20060054699A1 (en) Method and system for a static magnetic read/write head
US20090159701A1 (en) Payment cards and devices with enhanced magnetic emulators
US5159181A (en) Capacitive code reader with interelectrode shielding
US4967185A (en) Multi-directionally responsive, dual-status, magnetic article surveillance marker having continuous keeper
US5204526A (en) Magnetic marker and reading and identifying apparatus therefor
US5442865A (en) Passive magnetic position sensor
US5545885A (en) Method and apparatus for detecting and identifying coded magnetic patterns on genuine articles such as bank notes
US4665387A (en) Method and apparatus for target deactivation and reactivation in article surveillance systems
US3938125A (en) Antipilferage system and marker therefor
EP0777907B1 (en) Electromechanical switching device and arrangement with several such devices
USRE31211E (en) Magnetically coded identification card
AU723490B2 (en) Magnetic detector for security document
US4425511A (en) Planar coil apparatus employing a stationary and a movable board
US3676644A (en) Coded document and system for automatically reading same
US3243692A (en) Travelx-responsive s sensingx d device, particularly for control of fabricating machinery
KR100386062B1 (en) Cri menteol the speed sensor and / or the position
US5668533A (en) High security balanced-type, magnetically-actuated proximity switch system

Legal Events

Date Code Title Description
AK Designated states

Designated state(s): JP SU US

AL Designated countries for regional patents

Designated state(s): AT BE CH DE FR GB IT LU NL SE

WWE Wipo information: entry into national phase

Ref document number: 1985903262

Country of ref document: EP

WWP Wipo information: published in national office

Ref document number: 1985903262

Country of ref document: EP

WWR Wipo information: refused in national office

Ref document number: 1985903262

Country of ref document: EP

WWW Wipo information: withdrawn in national office

Ref document number: 1985903262

Country of ref document: EP