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Publication numberUS3590992 A
Publication typeGrant
Publication dateJul 6, 1971
Filing dateJan 30, 1969
Priority dateJan 30, 1969
Publication numberUS 3590992 A, US 3590992A, US-A-3590992, US3590992 A, US3590992A
InventorsSoderstrom Karl Gunnar Rune
Original AssigneeSoderstrom Karl Gunnar Rune
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Method and apparatus for examining and identifying banknotes and the like
US 3590992 A
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Description  (OCR text may contain errors)

United States Patent [72] Inventor Karl Gunnar Rune Soderstrom Skebokvarnsvagen 151, Bandhagen, Sweden [2 I 1 Appl. No. 795,215

[22] Filed Jan. 30, 1969 Division of Ser. No. 529,644, Nov. 7. 1966. Pat. No. 3,448,855

[45] Patented July 6, I971 [32] Priority May 2, 1966 [33] Sweden [54] METHOD AND APPARATUS FOR EXAMINING AND IDENTIFYING BANKNOTES AND THE LIKE 6 Claims, 3 Drawing Figs.

[52] US. Cl 209/73, 209/88 [5 I] Int. Cl B07c 5/06 [50] Field of Search 73/159, 104, 105, I56; 209/73, 111.6, 111.7, 75, 88

[56] References Cited UNITED STATES PATENTS 2,941,187 6/1960 Simjian 209/(PMS) 2,950,799 8/1960 Timms 3,448,855 6/1969 Soderstrom 209/(PMS) 209/88 X ABSTRACT: The disclosure involves a method for checking banknotes or the like in a checking station which includes the step of gauging mechanical dimensions at at least one distinguishin g area of the banknote. The gauged values obtained are compared with standard signals and a comparison signal produced which is then utilized to distinguish between genuine banknotes and forged or damaged banknotes. The disclosure also involves an apparatus for checking banknotes or the like and for passing genuine notes to an item dispensing device. The apparatus includes a gauging means for gauging mechanical dimensions at least one distinguishing area of the banknote. A comparator means is used for comparing the gauged values with standard values so as to produce a comparison signal. Utilizing means are provided which are responsive to said comparison signal to differentiate between genuine and forged or damaged banknotes. Means are provided for passing the genuine notes to a collection station and for returning notes which are forged or damaged.

METHOD AND APPARATUS FOR EXAMINING AND EDENTHFYHNG BANKNOTES AND THE LIKE This application is a division of patent application Ser. No. 592,644 tiled Nov. 7, 1966, now U.S. Pat. No. 3,448,855 entitled A Method and Apparatus for Examining and ldentifying Banknotes or the Like, preferably used in conjunction with vending machines.

The present invention relates to a detecting device for examining and identifying bank notes or the like, preferably for use in combination with a vending machine which accepts banknotes.

Devices for separating genuine banknotes from forged ones are previously known in automatic machines of the aforementioned type. In practice, however, previously known detectors have shown to be encumbered with several deficiencies, the most serious of which is their unreliability in distinguishing between genuine banknotes and accurately made copies of such notes, for instance photocopied banknotes.

Devices have been designed, for instance, which are provided with a plurality of photoelectric measuring stations, at which the ability of a banknote inserted in said devices to reflect light or permit light to pass through the same can be compared with the same characteristics of a genuine banknote or with certain standard values. It has been proved that the application of solely these means to identify banknotes, etc., does not always give positive results, since the tolerance limits in photoelectrical apparatus utilized for this purpose must be set very close, in order to increase the reliability of the device to detect forged banknotes. Among other things a much too large number of genuine banknotes have beenrejected, for instance such notes which are genuine but which are old and somewhat dirty and crumpled. The object of the present invention is to provide a detecting device of the aforementioned type, which is distinguished by its practically one hundred percent reliability with respect to differentiating between genuine and forged banknotes. Another object of the invention is to provide for a very large number of different possible combinations concerning the examined areas on the notes.

In accordance therewith the invention more particularly relates to a method for checking banknotes or the like and for passing genuine notes to an apparatus for dispensing items, such as gasoline, change, etc., said method comprising the steps of placing a banknote in a checking station, gauging at least one distinguishing area of said banknote in said checking station, comparing the values obtained from the gauging operation with standard values, producing a comparison signal, and utilizing said comparison signal to differentiate between genuine and forged or damaged banknotes, etc., and for passing genuine notes to a place of collection and returning forged or damaged notes.

It is possible by means of the method according to the invention to utilize a previously unused varying magnitude of banknotes, giving a high degree of reliability in the case of well used banknotes, as well as with forgeries in the form of photocopies and the like, by means of which forgeries it is otherwise possible to escape detection in a purely photoelectric indicator. it is not only the thickness of the banknotes which is sued, this being in itself known and which on its own does not provide a great degree of reliability, but that the difference in thickness between various determined measuring points on the banknotes are also gauged, i.e., the nature of the surface of the note at these points is indicated, and by means of this method it is thus also possible to distinguish polished photographic paper, which is a usual type offorged banknote.

The invention also relates to an apparatus for checking notes or the like and for passing genuine notes to a device for dispensing items, such as gasoline, change, etc., said apparatus comprising a checking station, gauging means for gauging at least one distinguishing area of said banknote in said checking station, comparator means for comparing the values obtained from the gauging operation with standard values, signal producing means for producing a comparison signal, and means utilizing said comparison signal to differentiate between genuine and forged or damaged banknotes, etc., and means for passing genuine notes to a collection station and returning forged or damaged notes.

Further characterizing features can be read from the following and said features are also defined in the accompanying claims.

The apparatus and method according to the invention will now be more closely described in connection with accompanying drawings which illustrate a particular embodiment.

Thus, F 16. 1 shows in perspective an apparatus according to the invention with a certain portion of the casing removed.

FIG. 2 shows in perspective the comparison means in the apparatus according to FIG. 1, at two gauging positions.

FIG. 3 shows a simplified electric wiring diagram for the apparatus according to the invention.

The apparatus according to the invention, shown in perspective in FIG. 1, is built in a casing 37. The apparatus comprises a gauging table 9 provided at its rear end with an insertion slot 27 and at its front end with a feed out drum 38. Banknotes or other types of promissory notes to be examined in the apparatus are fed in through said slot 27 in the direction of the arrow 26 and passed through the unit by means of a driving means which includes drive rollers. Genuine banknotes are fed out in the direction of arrow 26 by means of said drum 38. The said driving means includes an upper driving roller 10 and a lower driving roller 35. The shaft 84 of the roller 10 is driven by an electric motor M via a gear unit 5.

Each of the rollers 10 and 35 extend through the gauging table through a slot, the slot for roller 35 being visible in FIG. 1 and indicated by the reference numeral 6.

A- gauging means 7, mounted on the gauging table, is adapted to sense certain surface portions of the inserted notes, the said surface portions being those suitable for different banknotes. A magnetic changeover switch Ms is arranged so that its sensing arm 73 lies within the path of movement of the banknote.

Further, mounted on the gauging table is a photoelectric measuring tube 11, provided with a source of light and intended for measuring the amount of light reflected from the notes, and a second measuring tube 19 provided with an opposing source of light and located on the opposite side of the note for measuring the amount of light which passes through the notes.

The right-hand portion of the casing 37 contains a contact disc 24 provided with contact curves 20. The contact curves are adapted to cooperate with microswitches Kl-KS as sociating with arms 44 acting as contact breakers. The contact disc 24 is provided with a shaft 70 driven by said roller 35.

The motor M together with associating gear unit 5, shaft 84 and driving roller 10 are secured to a lever 67, at the one end of which is pivotally connected a connecting rod 68, associating with a magnet Mg which when energized attempts to draw the rod 68 downwards against the action of a spring 69. The lever 67 is vertically pivotally mounted at its other end on a shaft 71, at the wall ofthe casing 37.

A microswitch Mk is adapted to cooperate with the lever 67, as described below.

The gauging means 7 is shown in detail in FIG. 2.

A gauging magnet Mmg is secured to the gauging table and provided with a connecting rod 12 securely connected to the core of the magnet, and the free end of which is actuated by a coil spring 14 the lower end of said spring resting against the left end (as seen in the Figure) of a lever 15. Said lever 15 can be rotated at 16 and its right end (as seen in the Figure) is provided with a pin 17 which passes through a hole in a second lever 18 arranged at right angles to the lever 15 and which thus can be pivoted around the pin 17 in a vertical plane, perpendicular to the vertical pivoting plane of the lever 15. The lever 18 is provided with rounded upper portions 23 against which a lever 28 and 29 rest respectively at each end of the lever, the point of rotation of said levers 28 and 29 being indicated by the reference numeral 30. The other arm of the lever 2b and 29 is actuated from underneath by a rod 36 and 39 of a plunger 3i and 34 respectively. The said rods pass through holes in a plate 4l7 of the gauging table and the plunger heads are adapted to rest, whilst the gauging sequence is carried out, on a banknote Zl inserted in the slot Ml. Each of the plungers are held raised by a spring 43, the free end of which engages a groove ll in the plunger. The right ends (as seen in the Figure) of the levers 28, 29 actuate respective levers 45, 46, which are pivotable at 79 and each of which supports a contact spring 6B and 62 respectively. The contact springs 61. and 62 are each secured to the respective levers by means of a screw ltl which is insulated from the spring by means of an insulating Washer 49. The springs are insulated from associating levers by means of insulating supports 50. The screws 13 are intended for adjusting respective contact springs 6ll, 62. The plunge-rs Ill and 3d are provided with contact surface areas of different magnitude, for example, circular with an area relationship of 1:10 or rectangular measuring, for instance, 1.5 l5 mm. and l l5 mm. respectively (not shown) and, depending on the degree of unevenness of the paper note at specific gauging stations, the plunger of smaller area sinks further down into the surface pattern of the banknote at its respective gauging points. A gauged difference in the case of a genuine banknote, new as well as used, should lie between certain limits at these, suitably selected, gauging positions. The difference disclosed in the case of a smooth photographic paper is all too small and the tender will be refused even though the optical variables agree with those of a genuine banknote. A note which is too rough, such as possibly a forged note, also gives a negative reading. Naturally it is possible to reduce further the plunger areas, as well as also to change the shape of the contact surfaces, but in principle the smaller plunger is lowered down at the measuring stations between the crests" of the paper while the larger plunger rests on several crests" and gives the larger dimension.

The free ends of the springs 61, 62 are provided with a number of contacts, namely 65 and 73 on the spring 611, and 76 and 77 on the spring 62. The double contact 76 cooperates with a stationary contact 63 and a stationary contact 86, and the spring 6ll cooperates with another stationary contact 85. The double contact 7'7 is arranged on a perpendicularly bent end 78 of the spring 62 and cooperates with the contact 65 and second contact '75, mounted on a forked portion 64 of the spring 61. Naturally all contacts and arms are insulated from the base 47.

The reference numerals Rll-Rd in FIG. 3, which shows diagrammatically the electrical means included in the apparatus according to the invention, indicate relays, TR a transformer for net supply, C a capacitor and GL an indicating lamp. Further, FIG. 3 shows the motor M, the microswitches l(ll K and Mk, the magnetic changeover switch Ms, the magnet Mg, the gauging magnet Mmg and the contacts 63, 65, 75, 76, 77, 85 and 86. Current is supplied from the terminals F-O via the transformer TR and via the rectifier bridge Li.

A brief explanation of the function of the apparatus according to the invention will be given below.

A banknote, the genuiness of which is to be ascertained or which is to constitute the means of payment for goods, is inserted into the insertion slot 27, in the direction of arrow 25, until the front edge of the banknote reaches the sensing arm 73. As can be seen from H0. 3, the normally open connection Mr is closed (to upper contact in FIG. 3) so that current flows to the winding of the magnet Mg. The connecting rod 68 is thus drawn (FIG. l) downwards, whereby the lever 67 is also swung downwards. The banknote is thus clamped fast between the rollers lit) and 35. Driving current to the motor M is closed over the upper contacts of Mk, controlled by Mg, and the feed mechanism is set into motion.

The contact disc 24 is driven via the motor M and the rollers 10 and 35 by the shaft "7'0. When the disc 24 begins to rotate, the microswitch K2 is switched over (to lower position) and the lamp GL is extinguished. The lamp shines when the apparatus is in a state of rest and thus indicates to a customer or operator that the apparatus is ready for use. The program mechanism is so programmed that when the object to be gauged is fed by the driving rollers into a gauging position suitable for the said object, the apparatus stops for the measuring process and restarts when the capacitor (C), which holds R4, is discharged and R6 falls (to the upper position). The microcontact K4 and the program mechanism is momentarily closed and broken immediately before the apparatus, subsequent to checking an accepted, gauged object, has returned to rest position. K4 then emits an impulse to the pertinent vending apparatus instructing it to deliver the goods paid for (not shown).

The microswitches K11 and K3 are actuated by the contact disc 24 and thus switch over when the banknote has reached the gauging position. The current to the magnet Mg is then broken over Kl (dotted position), the roller lltll being lifted out of engagement with the banknote and the roller 35, which stop. Mk returns to home position owing to the actuation of the lever 6'7 and the motor stops, disconnected by Mk, Mk thus connects up the gauging means and the gauging magnet Mmg. Mmg then adjusts the gauging means according to FIG. 2 for gauging and the plungers 31, 3d abut respective portions of the banknote. Mmg is disconnected by means of a contact K5, controlled by the disc 24. K3 has been switched over and the current to the capacitor C and the relay winding R4 is broken. The capacitor C holds Rd withdrawn for a length of time, necessary to allow the gauging means to carry out the gauging function. The relay R4 falls with a certain time delay. R41 closes a contact and R2 is withdrawn, a current path thus passing to the magnet Mg via R2. The contact on R3 is closed if the banknote is false. if the banknote is genuine no current flows to the winding on R3, nor yet to the winding on R1. Relay R1 remains fallen and the motor M rotates forward when it is then connected up by Mk which is actuated by Mg. If the banknote is a forgery contact is made over one or more of the contacts in the measuring means (63, 65, 7, 76, '77, 85, 86). The R3-winding is then energized and R3 lies withdrawn so that current flows to the winding on Rt which is then withdrawn an locked. When the current in the capacitor C has ceased and R4 falls, an impulse to the winding on R2 is obtained and R2 is switched over and locked over its own contacts and passes current to Mg which is then withdrawn and Mk switches over, the motor M restarting in a direction determined by the fact as to whether the banknote is genuine or false, depending on the mutual position of the contacts of the measuring means. At the same time as Rd is disconnected the current over Mk to the magnet Mmg is broken and the difference-gauging means (FIG. 2) returns to home position, the banknote being able to pass freely in either direction, depending on whether the said note is genuine or false.

The apparatus according to the invention examines the variations in height or thickness appearing on banknotes, and which in genuine notes reoccur from note to note, for instance, height differences caused by text, figure marks, water marks, stamps, and portraits etc.

As can be seen from FIG. 2, it is necessary in order to show a difference in height to gauge at least two positions, which means that at least two plungers 31, 34, suitably of different contact area must be used.

The system for amplifying the differences in height has been shown as a system of levers but it is obvious that gear systems, wheel systems, screw systems or optical amplifying systems can also be used. By utilizing such an amplifying system it is possible to register that minutest variation in height (in the order of O.5-2 hundredths of a millimeter), such as occurs in genuine banknotes, and amplify the same to magnitudes which can be registered practically.

The designer shape of the plunger-s 3H, 3% is suitably selected so that, for instance, a plunger 3d provided with a small head or measuring plate is used when measuring bottom heights or the thickness of the paper of a banknote, while a plunger 31 having a gauging plate of larger area and of suitable surface configuration is used to measure the height of, for instance, an image, an emblem, text or face or other convenient protuberances on a banknote. Depending on the position of the plungers against the banknote the levers 28, 29 and thus the springs 61, 62, lie positioned so that either the contacts 76, 77 rest in neutral position (genuine banknote) or are in contact with a countercontact (63, 86, 65, 75).

The aforementioned apparatus also provides for indication of the correct or wrong thickness of a banknote, i.e., the position of a plunger is compared with a reference which is equal to the position of a stationary contact.

The invention according to the aforegoing may be combined, for instance, with a photoelectric gauging mechanism for gauging the light-permeability and light-reflexion-ability of the banknote. Similar apparatus have been designed for identifying banknotes used in vending machines and machines for giving coins in exchange for banknotes, i.e., for the same field of use as the aforementioned invention. The object of this last-mentioned piece of equipment, which may serve as a valuable complement to the aforegoing apparatus, is also to return false or damaged banknotes and to pass genuine banknotes to a collecting station in the vending machine. Arranged in a special piece of similar photoelectric equipment, which may also be combined with the aforegoing apparatus, are at least two gauging means for gauging the ability of a note to reflect light and its permeability to light, along at least one line on the note and comparing means for comparing the gauged values with determined standard values.

It is also possible with the photoelectric indicating process to gauge banknotes, which are held stationary, as in the case of the dimension measuring process according to the aforegoing, and thereby firstly roughly sorting the notes and then finely sorting the same by gauging a certain dimension. The photoelectric gauging process should thus be carried out at wider tolerance limits.

A combination of this type hives a high degree of certainty in detecting false and damaged banknotes, and, furthermore, greater flexibility concerning the use of the apparatus with various types of banknotes or the like.

The wiring scheme shown in FIG. 3 includes, in addition to the components necessary for measuring thickness and difference in magnitude, also includes a simplified means for photoelectric gauging, comprising two measuring tubes M ll, F01 and M12, F02 respectively, two tongue element relays TEl, TEZ having associating windings 80, 81 and 82, 83 respectively, and potentiometers P1, P2 and a rectifier bridge The function of the arrangement is as follows:

At least one measuring tube measures the light-permeability or/and light-reflection on selected dark portions of the object to be measured (e.g., M11, Fcl) at least one tube measures, in the same way, selected light portions (e.g., M12, Fc2).

The current from L2 passesthrough for instance the photocell Fc]l-through the winding 80 of the tongue element TEl. At the same time the current passes from LZ-via the potentiometer Pl-to the winding 81 in T51. The windings 80 and iii are mutually counteracting. P1 is so adjusted that the windings, in the case of a genuine object, compensate each other, and consequently the contact of the tongue element T1 is broken. Corresponding adjustment occurs for TE2.

if the object to be measured is false or damaged, the current in the winding $0 or 82 increases or decreases in relation to the adjusted current through 81 and 83 respectively. The tongue element contacts are thus closed. lf any of the tongue ele' ments lie closed when R4 falls, R3 is withdrawn and passes current to the winding on R1, which is withdrawn and locked in the reverse position of the motor. The apparatus then operates in reverse and the banknote is returned through the insertion slot 27.

Since the gauging process by means oflight in apparatus according to the invention is of a secondary significance and merely constitutes a means supplementary to the measuring process of thickness and difference in magnitudes, it can be set at fairly wide limits, and consequently dirty and partly miscolored copies of the object to be measured may also be accepted.

The invention can be modified in various ways with respect to the described embodiment without departing from the scope of the inventive idea, thus it is conceivable that the gauging of the thickness can be efiected by means other than mechanical ones, such as free-blowing instruments, X-ray apparatus, laser rays, using said banknote as a capacity member in an electric circuit and by means of acoustic measurement, etc.

What I claim is:

1. A method for checking banknotes or the like and for passing genuine notes to an apparatus for dispensing items,

such as gasoline, change, etc., said method comprising the steps of placing a banknote or the like in a checking station placing said banknote in a mutually stationary position with gauge means having a limited measuring area in relation to the banknote area, positioning said gauge means at a characteristic portion of said banknote, gauging mechanical dimensions at one distinguishing portion of said banknote or the like in said checking station, comparing the values obtained from the gauging operation with standard values, producing a comparison signal, and utilizing said comparison signal to differentiate between genuine and forged or damaged banknotes or the like and for passing genuine banknotes or the like to a place of collection and returning forged or damaged banknotes or the like.

2. An apparatus for checking banknotes or the like and for passing genuine banknotes or the like to a device for dispensing items such as gasoline, change, etc. said apparatus comprising a checking station, means for gauging mechanical dimensions at one distinguishing area of said banknote or the like in said checking station, said means comprising measuring members having a limited measuring area in relation to the area of said banknote, said gauging means being operative when said gauging means and said banknote are in mutually stationary positions corresponding to a characteristic portion of said banknote, comparator means for comparing the values obtained from the gauging operation with standard values, signal producing means for producing a comparison signal, and means utilizing said comparison signal to differentiate between genuine and forged or damaged banknotes or the like, and means for passing genuine banknotes or the like to a collection station and returning forged or damaged banknotes or the like.

3. An apparatus for checking banknotes or the like and for passing genuine notes to a device for dispensing items, such as gasoline, change, etc., said apparatus comprising conveyor means to transfer a banknote or the like to a measuring table, gauging means for gauging mechanical dimensions at one distinguishing area of said banknote or the like at said measuring table, means for comparing the values obtained from the gauging operation with standard values, means for producing a comparison signal, and means for utilizing said comparison signal to difi'erentiate between genuine and forged or damaged banknotes or the like and for controlling said conveyor means to convey genuine notes or the like to a collection means and to return forged or damaged banknotes or the like to the customer.

4. A method for checking banknotes or the like and for passing genuine banknotes or the like to an apparatus for delivering items, such as gasoline, change, etc., said method comprising the steps of placing a banknote or the like in a checking station, gauging mechanical dimensions at at least one distinguishing portion of said banknote or the like in said checking station, gauging optic characteristics at at least one distinguishing portion of said banknote or the like in the same checking station, comparing the values from the gauging operation with standard values producing a first comparison signal, comparing the values from the optic measuring with standard values producing a second comparison signal and utilizing said comparison signals to differentiate between genuine and forged or damaged banknotes or the like and for passing genuine banknotes or the like to a place of collection and returning forged or damaged banknotes or the like.

5. A method for checking banknotes or the like as defined in claim ll comprising the further steps of gauging optic characteristics at at least one distinguishing portion of said banknote or the like in the same checking station, at least one optic characteristic being measured from light reflected against the note and at least one characteristic from light passed through the same note in the same checking station, and utilizing said comparison signal to differentiate between genuine and forged or damaged banknotes or the like, and for passing genuine banknotes or the like to a place of collection and returning forged or damaged banknotes or the like, and

determining whether or not the magnitudes or said signals' from the optic measurings lie within a pertinent predetermining range of values for the same purpose.

6. An apparatus for checking banknotes or the like and for delivering genuine banknotes or the like to a device for dispensing goods, such as gasoline, change, etc., said apparatus comprising a checking station, means for gauging mechanical dimensions at at least one distinguishing portion of said banknote or the like in said checking station, comparator means for comparing the value obtained from the gauging operation with at least one standard value, signal producing means for providing a comparison signal, optical measuring means for measuring optic characteristics of the same banknote or the like in said checking station at distinguishing portions of said banknote or the like, means for producing measuring signals representing said measured optic characteristics, and means utilizing said comparison and measuring signals to differentiate between genuine and forged or damaged banknotes or the like and means for passing genuine banknotes or the like to a collecting station and returning forged or damaged banknotes or the like.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2941187 *Dec 30, 1957Jun 14, 1960Luther G SimjianApparatus and method for determining the character of a document
US2950799 *Feb 7, 1952Aug 30, 1960Alan FosterApparatus for identifying paper money, or the like, as genuine, and for making change or the like
US3448855 *Nov 7, 1966Jun 10, 1969Soderstrom Karl Gunnar RuneMethod and apparatus for examining and identifying bank notes or the like,preferably used in conjunction with vending machines
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3930582 *May 17, 1974Jan 6, 1976Oesterreichische National BankSystem for testing paper money and the like
US4318484 *May 6, 1980Mar 9, 1982Datasaab AbDevice for sorting out individual articles which differ from the main quantity in a consecutive feedout
US4348656 *Oct 16, 1979Sep 7, 1982Ardac, Inc.Security validator
US4513439 *Jul 12, 1982Apr 23, 1985Ardac, Inc.Security validator
US6802760 *Mar 19, 2003Oct 12, 2004Steven G. GoldsteinDisk restoration service vending machine
US8464875 *Jun 6, 2007Jun 18, 2013De La Rue International LimitedApparatus for analysing a security document
US8472676Jun 6, 2007Jun 25, 2013De La Rue International LimitedApparatus and method for analysing a security document
US20100163466 *Jun 6, 2007Jul 1, 2010De La Rue International LimitedApparatus for analysing a security document
EP0028089A2 *Oct 13, 1980May 6, 1981Ardac, Inc.Security validator
WO1981001211A1 *Sep 18, 1980Apr 30, 1981Ardac IncSecurity validator
Classifications
U.S. Classification209/534, 209/555
International ClassificationG07F7/00, G07D7/00, G07F7/04
Cooperative ClassificationG07D7/00, G07F7/04
European ClassificationG07D7/00, G07F7/04