FR2695751A1 - Partially modifiable memory card for card reader system - has series of fusible memory elements of known operating characteristics on printed circuit on support card, and access contacts for coupling to card terminals - Google Patents

Abstract

The card contains at least one modifiable memory element (1,2,..10), a printed circuit (12) and first and second access contacts (F1,F2,..,F10; M1,M2) electrically connected to terminals (1a,2a,..,10a; 1b,2b,..,10b) on the card. The data contained in the memory (1,2,..,10) can be electrically modified. Each memory element is a fuse inserted in the printed circuit. The characteristics of the fuses are chosen, so that the fuse is ruptured by a current having a predetermined intensity and duration, but without damaging the printed circuit. USE/ADVANTAGE - Suitable for various types of vending machine. Similar to bank card, telephone card etc. Simple and very cheap design, effective and robust.

Description

 The present invention relates to an information medium with modifiable memory, and more particularly an information medium with modifiable memory comprising a support card, at least one memory element carried by the card and comprising a first and a second terminal, a circuit printed on one face of the support card and comprising at least a first access contact electrically connected to at least a first terminal of a memory element, and at least a second access contact electrically connected to at least a second terminal of a memory element, the information contained by said memory element being able to be modified electrically.

 The present invention also relates to an information carrier reader suitable for using an information carrier according to the invention, as well as a system constituted by an information carrier according to the invention inserted in a reader according to the invention. invention for controlling the operation of a device to which said reader is connected.

 Cards of the aforementioned type are known, called smart cards, which comprise a semiconductor memory device, for example in the form of an array of diodes or pairs of diodes. Such cards are used, for example, as bank cards or as telephone cards.

 In the case of telephone cards, the memory is initially in a configuration which corresponds to a capital formed by a given number of telephone communication units: as the card is used, the memory of it records the number of units consumed, the user knowing the number of units still available on his card.

 Such cards have many advantages, and their use has grown considerably in recent years.

 However, these cards are relatively expensive, in particular because of the unit cost of the chip with which they are equipped.

 The use of these cards is therefore reserved for relatively complex and repetitive operations for which their price does not constitute an obstacle to their use.

 On the other hand, there are many simple operations, relatively inexpensive, which are carried out by simple machines which can be controlled, for example, by inserting a token or coins into a slot, for example the use of a vacuum cleaner. to clean the interior of a motor vehicle, or that of a vehicle washing machine, or that of a hot drink dispenser, for example coffee. In particular, it is necessary to collect the tokens at regular frequency to put them back into service. It is also very impractical to keep with you one or more tokens, heavy and bulky. The use of coins can lead to acts of vandalism.

 In particular, tokens or coins are very difficult to lend to commercial promotional operations with distribution, for example in mailboxes, of free coupons for a trial or a very small number of trials of such a transaction.

 There is therefore a need for a very simple, very inexpensive information carrier, usable for controlling operations of simple automata, particularly suitable, because of its very low price, for operations of commercial promotions of all kinds.

 The object of the present invention is to remedy the drawbacks of known cards, and to provide an information medium of the aforementioned type which is of extremely simple structure, of very low price, while being robust and reliable, and which makes it possible to easily use simple machines.

 According to the invention, the information medium with modifiable memory of the aforementioned type is characterized in that each memory element is a fuse element inserted in said printed circuit, the nature and the electrical characteristics of this fuse element being chosen for that this element is destroyed when a current is passed through it with a predetermined intensity and duration which does not damage the printed circuit.

 We know how to make fuses at very low prices. It is easy to destroy such elements and thus modify the information contained by such a memory element, for example to record a use of a particular automaton. Such fuse elements are also robust and reliable.

 The merit of the present invention is precisely to have thought of replacing the very elaborate chip of a chip card with very inexpensive rustic elements to meet needs to which a conventional chip card is not suitable due to its unit cost.

 According to an advantageous version of the invention, the information medium comprises at least one group of access contacts comprising at most sixteen contacts arranged in two lines to form a standardized multipoint connector for a smart card, and each fuse element is a resistant element produced by depositing a thin layer of a conductive material based on carbon powder or equivalent, conductive plastic film for example.

 The constituents of the support of the invention are therefore constituents available or achievable at low prices.

 According to a preferred version of the invention, the information medium also comprises two non-destructible elements belonging to said printed circuit and having predetermined electrical characteristics very different from those of the elements forming fuses and chosen so as to form an identification code , the first and second terminals of these non-destructible elements being connected respectively to a first and to a second access contact, and the printed circuit is covered with an insulating film which has an access opening in front of each of said contacts access and in front of each of the elements forming fuses.

 According to another aspect of the invention, the information carrier reader conforming thereto comprises connection means adapted to be connected to the access contacts of the printed circuit of said support, and means for passing said current through intensity and duration predetermined between the first and second access contact connected respectively to the first and to the second terminal of a fuse element in order to destroy said fuse element.

 The invention also relates to a system consisting of an information medium according to the invention inserted in an information medium reader according to the invention to trigger the operation of a device to which said reader is connected.

 Other features and advantages of the invention will become apparent from the detailed description below.

In the accompanying drawings, given solely by way of nonlimiting examples:
- Figure 1 is a top view of an information carrier card according to the invention;
- Figure 2 is an electrical diagram of the printed circuit made on the card of Figure 1;
- - Figure 3 is an enlarged view of a detail of Figure 1;
FIG. 4 is a top view of an embodiment of the printed circuit corresponding to the detail shown in FIG. 3.

 In the embodiment shown in the figures, the card 11, which for example has the standardized format of a bank card or a telephone card, is an information medium with modifiable memory.

 This card 11 comprises in known manner at least one memory element 1 carried by the card 11 and comprising a first and a second terminal la and lb, a circuit 12 printed on one face of the support card 11 and comprising at least a first contact access F1 electrically connected to at least a first terminal la of a memory element 1, and at least a second access contact M1 electrically connected to at least a second terminal lb of a memory element 1, l ' information contained by said memory element 1 which can be electrically modified.

In the example shown in detail in FIGS. 2 to 4, the card 11 comprises ten memory elements, numbered from 1 to 10, each comprising a first terminal 1a to 10a and a second terminal 1b to 10b. It also includes twelve first access contacts numbered F1 to
F10 and M1 and M2, and two second access contacts C1 and Ca.

 Each first access contact F1 to F10 is electrically connected to the first terminal 1a to 10a of the corresponding memory element having the same number 1 to 10. The second access contacts M1 and M2 are electrically connected by a common conductor 13 at the second terminal 1b to 10b of the various memory elements 1 to 10.

 The card 11 itself is made up of a support made of a common material such as cardboard, PVC or other suitable plastic material.

 On this support is deposited in a first operation, by screen printing or by any other means, a thin layer of silver or other highly conductive material to form the electrically conductive tracks and contacts of the printed circuit 12. After baking, these tracks should preferably have a resistivity such that the electrical resistance between two points distant from the circuit 12 is less than 2 ohms.

 The printed circuit 12 shown in Figures 2 and 4 includes ten first access contacts F1 to F10, two second access contacts M1, M2 and two other access contacts C1, C2 whose function will be seen below.

 These fourteen contacts are, in known manner, arranged in two lines to form a standardized multi-point connector for a smart card. This connector makes it possible, after insertion of the card 11 into an appropriate reader, to establish the appropriate electrical or electronic connections between the elements of the card 11 and an external management system, the function of which will be seen below. We know that such a standardized connector can include any number of contacts less than or equal to sixteen.

 According to the invention, each memory element 1 to 10 is a resistant element forming a fuse inserted in the printed circuit 12. The resistance and the nature of this resistant element forming a fuse 1 to 10 are chosen so that this element 1 to 10 is destroyed. when a current is passed through it of a predetermined intensity and duration which does not damage the printed circuit 12.

 The resistive elements 1 to 10 are, in a second operation, produced by deposition, by screen printing or by any other means, of micro-fuses constituted by a paste of a special mixture based on carbon powder or equivalent. These micro fuses have, for example and approximately, a length of 3 mm, a thickness of 7 microns, a width of 0.2 mm. After cooking, these micro-fuses have, for example, an ohmic resistance of approximately 10 ohms. Fuse values higher than zero ohm are used to avoid possible fraud by short circuit r deposit of solder or conductive adhesive.

 In a third operation, two non-destructible resistors R1 and R2 were deposited on the card 11, for example by screen printing, which do not fulfill the function of fuses. These non-destructible resistors R and R2 belong to the printed circuit 12 and each have a predetermined electrical resistance significantly different from that of the fuse resistant elements 1 to 10. These electrical resistors have respective specified values comprised for example between 100 ohms and 500 kiloohms and chosen so as to form an identification code for a specific use of each card. Such a resistance range makes it possible to easily constitute a very large number of pairs of two values distinct from each other and adapted to be easily recognized and identified to serve as codes. The first terminals Ria and R2a of the resistors R1, R2 are connected respectively to the first access contacts C1 and C2, and their second terminals Rlb and R2b are connected to the common conductor 13. Such a code makes it possible to avoid errors or fraud.

 In a fourth operation, an insulating film which protects the printed circuit 12 and is also used for decorating the card is deposited on the face of the card 11 carrying the printed circuit 12, and preferably on both sides. Such an operation is known in itself and can be carried out in any manner, for example by screen printing or by printing.

 This insulating film has an opening 14 in front of each of the access contacts F1 to F10, C1, C21 M1 and M2, to allow the electrical connection between said contacts and the corresponding feelers, known in themselves, of a standardized connector.

 The insulating film also has an opening acting as a chimney 15 in front of each of the fuses 1 to 10 to allow the evacuation of the particles which volatilize during the destruction of the corresponding fuse, and to avoid the recombination of these particles. This chimney also makes it possible to visually check whether the card still has intact fuses. It is not compulsory if the material constituting the fuses can volatilize in a confined space under the insulating film without risk of reconstitution of a conductive element.

To destroy each of fuses 1 to 10, which has a resistance of approximately 10 ohms, for example fuse 1, apply between terminals la, lb of this fuse 1, therefore between contact F1 and contacts M1, M2, a DC voltage of approximately 12 V for approximately 0.5 seconds. This results in a current of intensity 12/10 = 1.2
A approximately which causes the material of fuse 1 to volatilize immediately, so that the corresponding circuit has a resistance which goes from about 10 ohms to several megohms.

It can thus be seen that cards comprising two contacts C1 can be produced according to the above model,
C2, of identification code, at least one and up to twelve first access contacts each connected to a fuse, and one or two contacts M1, M2 for the common conductor 13, two contacts being necessary when there is several fuses to limit the resistance of the supply circuit of each fuse. The total number of contacts is at most equal to sixteen if you want to use the standardized smart card connector.

 Thus, a card comprising a single fuse has four contacts, and a card comprising twelve fuses comprises sixteen contacts, these cards and the cards comprising an intermediate number of fuses which can all be read by a standard connector with sixteen contacts.

 A reader adapted to use a card according to the present invention must thus include such a standardized connector with sixteen contacts, housed inside a standardized slot for introducing a card 11, as well as means for passing the aforementioned current of predetermined intensity and duration between the first and the second access contacts F1, F2, ... 1F10; M11 M2, connected respectively to the first and to the second terminals la, 2a, ..., 10a; lb, 2b, ..., 10b, of fuse 1, 2, # .., 10, in order to destroy said fuse 1, 2, ..., 10.

Such a reader preferably includes a microprocessor adapted to perform the following operations:
a) detect the presence of a card in the reader;
b) detect and recognize a possible defect;
c) recognize the application;
d) detecting the presence on the support of at least one intact fuse 1;
e) controlling, the passage between the first and the second access contact F1, M1 corresponding to the fuse 1, of the current of predetermined intensity and duration in order to destroy said fuse 1;
f) send a predetermined signal to the automatic device to which this reader is connected to control an operating operation of this device.

In detail, and provided that a card 11 still having at least one intact fuse 1 is inserted in the correct direction in the card reader, the microprocessor can perform the following conventional operations as soon as the card 11 is inserted into the reader:
- - detect the presence of a card via an electrical contact placed at the bottom of the reader slot;
- in the event of the presence of a card, direct the program to a "triggering of the test by a resistance card forming fuses" branch thereof;
- test the two contacts C1, C2 and measure the two resistors R1 and R2 anti-fraud and identification, in order to recognize the application intended for the card;
- in the event of fault detection (ohmic resistances out of tolerance), declare the faulty card, display the number "0" on a counting indicator and put the device on hold;
- if the first check is correct, test the fuses one by one, starting with the number 1. Check the presence of an intact fuse, and check the ohmic resistance, which must be between 4 and 15 ohms (average value 10 ohms ), of it;
- if the resistance measured is good, memorize the validity of the fuse checked, and go to the next fuse by making the same test, and so on until encountering a defective fuse or reaching the total number of fuses on the card. Count the fuses simultaneously.

- go back a notch back to the first access contact of the last intact fuse identified and stored, and send the electric discharge by applying a voltage of 12 volts for 0.5 seconds. Check the destruction of the fuse, otherwise make three destruction attempts;
- if the destruction tests are unsuccessful, declare the card 11 defective, display the number "0" and put the device on hold;
- if the fuse is destroyed, initiate the normal operating cycle of the device to which the reader is connected, and display the number of fuses still usable on the meter;
- at the end of a normal cycle, remove the card from the reader, and reinsert it again if you want to cause a new operating cycle.

 Because of its very low cost, the card according to the invention can also be used as a hidden support for a lottery number, to replace the cartons bearing a hidden number with a coating that is scratched to reveal said number and check whether this number is or is not a winning number.

 To this end, the card has a single fuse element, for example the resistor 1, several non-destructible elements, such as R1 and R2, constituting a first identification code for a well-defined use of the card, and several others non-destructible elements, located on the card in place of at least some of the resistors 2 to 10: these latter elements thus constitute a second identification code representing the number assigned to the card.

 The reader adapted to read such a card must then check the first identification code to check the correct use of the card, read the second identification code, compare this second code to the list of winning numbers and announce if the number is winner or loser, finally destroy the fuse to avoid any new fraudulent use of the same card.

 Of course, the invention is not limited to the embodiment which has just been described, and many changes and modifications can be made to it without departing from the scope of the invention.

 It is thus possible to arrange the contacts in a different way than that described, and not to use the dimensions and configurations of the cards, contacts and standardized readers.

 It is also possible to have several sets of contacts placed on different cards placed at different ends and on different faces of the card.

 The resistors can be replaced by other elements forming fuses, for example by microcapacitors capable of breaking and becoming conductive, and the non-destructible elements by elements other than resistors.

Claims (12)

 1. Information medium (11) with at least partially modifiable memory, comprising a support card (11), at least one modifiable memory element (1, 2, ... 10) carried by the card (11) and comprising first and second terminals (la, 2a, ..., 10a; lb, 2b,.,., 10b), a circuit (12) printed on one face of the support card (11) and comprising at least a first access contact (F1, F21 ..., F10) electrically connected to at least one first terminal (la, 2a, ... 10a) of an modifiable memory element (1, 2, ... 10), and at least one second access contact (M1, M2) electrically connected to at least one second terminal (lb, 2b, ..., 10b) of an modifiable memory element (1, 2, ..., 10 ), the information contained by said modifiable memory element being able to be electrically modified, characterized in that each modifiable memory element (1, 2, ..., 10) is a fuse element inserted in said printed circuit (12) , nature and characteristics electric elements of this fuse element (1, 2, ..., 10) being chosen so that this element is destroyed when a current is passed through it of a predetermined intensity and duration which does not not damage the printed circuit (12).  2. Information carrier according to claim 1, characterized in that it comprises at least one group of access contacts comprising at most sixteen contacts (F1, F2, .. rF10, C1, C2, M1, M2) arranged in two lines to form a standardized multi-point connector for a smart card.  3. Information carrier according to one of claims 1 or 2, characterized in that it further comprises at least one non-destructible memory element (R1, R2) belonging to said printed circuit (12) and having a predetermined resistance significantly different from that of the fuse-forming elements, the first and second terminals (R1a, Rlb; R2a, R2b) of said non-destructible element being connected respectively to a first (C1, C2) and a second (M1, M2) access contacts.  4. Information carrier according to claim 3, characterized in that it comprises at least two non-destructible elements (R1, R2) whose electrical characteristics are chosen so as to form an identification code.  5. Information carrier according to any one of claims 1 to 4, characterized in that it comprises at least one second access contact (M1, M2) connected to the second terminal (lb, 2b, .. ,, 10b; R1b, R2b) of the fuse-forming elements (1, 2, ..., 10) and where appropriate non-destructible elements (R1, R2).  6. Information carrier according to any one of claims 1 to 5, characterized in that the printed circuit (12) is covered with an insulating film, and in that said insulating film has an access opening ( 14) in front of each of said access contacts (F1, F2, ..., F10, C1, C2, M1, M2).  7. Information carrier according to claim 6, characterized in that the insulating film also has an access opening (15) in front of each of the fuse-forming elements (1, 2, ..., 10).  8. Information carrier according to any one of claims 1 to 7, characterized in that each fuse element (1, 2, ..., 10) is a resistant element produced by depositing a thin layer d '' a conductive material based on carbon powder or equivalent  9. Information carrier according to any one of claims 1 to 8, characterized in that it comprises a single fuse element, several non-destructible elements constituting a first identification code of a use, and several others non-destructible elements constituting a second code scrutinized in said use. C2) of the printed circuit (12) of said support (11), and means for passing said current of predetermined intensity and duration between the first and the second access contact (F1, F2, ..., F10; M1, M2) connected respectively to the first and to the second terminal (la, 2a, ..., l0a; lb, 2b, ..., 10b) of a fuse-forming element (1, 2, ..., 10) in order to destroy said element (1, 2, ..., 10).  10. Information carrier reader adapted to use an information carrier (11) according to any one of claims 1 to 9, characterized in that it comprises connection means adapted to be connected to the contacts of access (F1, F2, ..., F10, M1, M2, C1,  11. Media reader according to claim 10, characterized in that it comprises a microprocessor suitable for carrying out the following operations:  a) detecting the presence of a support (11) in the reader;  b) detect and recognize a possible defect;  c) recognize the application;  d) detecting the presence on the support (11) of at least one element (1, 2, ..., 10) forming an intact fuse;  e) controlling the passage, between the first (F1, F2, ..., F10) and the second (M1, M2) access contacts corresponding to said element (1, 2, ..., 10) forming a fuse, from current of predetermined intensity and duration in order to destroy said element (1, 2, ..., 10);  f) send a predetermined signal.  12. System constituted by an information medium (11) according to any one of claims 1 to 9, and by an information medium reader according to one of claims 9 or 10 and adapted to receive said medium , to control the operation of a device to which said reader is connected.