WO1995031792A1

WO1995031792A1 - Supplementary coding on inductive debit cards and reading process

Info

Publication number: WO1995031792A1
Application number: PCT/BR1995/000029
Authority: WO
Inventors: Enio Calcavara Junior; Antonio Massao Nishikawa
Original assignee: TELECOMUNICAÇõES BRASILEIRAS S/A - TELEBRÁS
Priority date: 1994-05-12
Filing date: 1995-05-11
Publication date: 1995-11-23
Also published as: CZ332696A3; JPH10503863A; CN1147874A; CA2188873A1; BR9401059A; GEP19991761B; US5984192A; KR970703020A; PL317196A1

Abstract

Supplementary coding on inductive debit cards and reading process refers to supplementary information regarding variables such as date of issue and country in which the card is valid, which are included without any change in the number of credits on the card by using the front and back handling strips (17, 18). Such an encoding comprises the division of said strips, in a number of segments or tracks (41, 42, ... 49) equal to the number of cell columns on the card, coinciding the center of said tracks with the axes (31, 32, ... 39) of said columns; the metallized tracks correspond to bit '1' and the non-metallized tracks to bit '0', the four tracks located at the corners of the card (41, 49, 41', 49') being always metallized. The reading of the information on the card is carried out during the insertion of the card (30) into the reading head by the row of sensors (64) the farthest away from the entrance slot (69). On detecting the presence of a pair of metallized tracks on the corner of the card, the bits contained in either strip are read and stored in a temporary register for a later interpretation.

Description

SUPPLEMENTARY CODING ON INDUCTIVE DEBIT CARDS AND READING PROCESS

- SPECIFICATION -

The present invention concerns the improvement of disposable inductive debit cards, such as the ones described in patent document BR 9201380-5 and BR

9304503-4 and, specifically, to the insertion of supplementary information on said cards, as well as to its reading using the existing reading devices as described in said patents.

Inductive debit cards based on concepts originally contained in patents BR 7804885, DE 3650959 and US 4029945 are well known and are widely used as credit elements in public telephone systems. Figure 1 exemplifies the main features of a known card, akin to the one in figure 1 of above mentioned document BR 9304503-4, containing a plurality of credit elements 12, arranged in 6 rows and 9 columns, totalling 50 usable credits since four of the cells at comers 13, 14, 15 and 16 are used as indexing elements. The card also has blank strips 17 and 18, located between said central area and front end edge 19 and back edge 21 which are made use of during insertion and withdrawal of the card from the reading head.

Even though the shown ca: s suitable for experimental use, or small scale applications, the commercial use on a large scale basis requires the inclusion of additional information, such as, for instance, the following:

* Card validation date * Code of the country issuing the card

* Manufacturer's identification code

The inclusion of this information in central area 11 would necessarily reduce the number of available credits on the card. On the ot ~ hand, including s -id information on strips 17 and 18 entails as a drawback the need to modify the reading head, since the existing ones do not have sensors positioned at said strips. In view of the large number of telephone sets of this kind are already in operation, such a solution would require the expenditure of large amounts of money, materials and labor, as all the installed reading heads would have to be substituted. From the foregoing, the main objective of the present invention is the provison of a way of including said supplementary information on cards while keeping the number of credits unchanged, and associating it to a reading process of this information which uses the already existing reading heads, eliminating the need of any structural change to the latter.

This and other objectives are achieved by the present invention by including metallized elements on the handling strips, having shapes and dimensions such that allow for the reading of data on a card in motion.

According to another aspect of the present invention, said reading is carried out during the time said strip is passing by the row of sensors placed the farthest away from the card inserting slot.

According to still another aspect of the present invention, said supplementary information is read off independently of the card's orientation in the reading head. According to another aspect of the invention, the card is provided with indexing elements which allow to detect, during the insertion of the card into the reading head, the existence of said metallized elements while passing by the row of sensing coils that read off the informations there contained.

The previously mentioned characteristics, as well as other aspects and advantages of the present invention, will become more evident from a detailed description of a preferred embodiment and of the attached figures where:

Figure 1 shows a known inductive debit card, such as described in document BR 9304503-4.

Figure 2 shows the placement of the information carrying elements in the handling strips of an inductive debit card, according to the principles of the present invention.

Figure 3 shows an example of information coding, as well as the reading direction of the information, according to the principles of the present invention. Figure 4 shows the different positions of the card relative to the reading head, during the several stages of its insertion, acording to the principles of the present invention.

Figure 5 shows, by means of a flowchart, the steps involved in the reading of supplementary information on a card, according to the principles of the present invention.

Figure 6 shows an alternative way of achieving the aims of the present invention with an increase in the number of data items inserted into the handling strips of a card. According to figure 2, the front handling strip 17 is divided, in the direction of the card width, in as many segments or tracks 41, 42, 49, as the cell columns on the card, said segments being aligned with the axes 31, 32, ... 39 of said columns. The rear handling strip 18 is divided in the same way in segments 41', 42' .... 49'. According to the principles of the present invention, the four segments 41,

49, 41', 49', located on the corners of the card, are always metallized; in the remaining segments, the presence or absence of metallization wil correspond to the data bit — 1 our 0, respectively — represented by each segment.

Still according to the principles of the present invention, the data bit sequences are identical on strips 17 and 18, which allows the reading of the information independently of the position the card was inserted into the reading head. Moreover, the use of the available bits will depend on the number of variables one wishes to represent, as well as on the range of possible values of each variable.

Figure 3 shows how two variables can be encoded on the card shown in figure 2 , such as, for instance, the issue date and the country issuing the card. From a total of 7 available bits, 4 bits from blocks 51 and 51' are made use of to encode the issue date of the card and 3 bits from block 52 and 52' to codify the country issuing the card. Considering, for instance, that it is wished to encode the quarter in which the card was isued and, then block 51 allows 2⁴ = 16 quaterly issuing periods, equivalent to 4 years, while block 52 allows to encode 2³ = 8 different countries. In the exemplificative encoding of figure 3, tracks 42 and 44 have no metallization, and segments 43 and 45 are metallized; the reading of the code, carried out in the direction 63 (left-hand border 61 to right-hand border 62 of the card) gives the binary coded number 0101, indicating that the card was issued on the 5th quarter counted from a standard reference date. In block 52, segments 46 and 47 are not metallized, while track 48 is metallized, indicating the binary number 001, corresponding, for instance, to cards issued in Brazil. In this way, cards having a different code in block 52, as for example, 002, 003, etc., would be rejected since these correspond to cards issued in other countries (for example, 002 = Uruguay, 003 = Argentina, etc.). As previously mentioned, the encoding by metallizing segments of strip 18 would be identical to the one of strip 17, thus tracks 43', 35' and 48 are metallized while the remaining ones are not, since reading directions 63' and 63 are the same in both strips 17 and 18.

The designation of the side edges is set by convention. In this case, "left- hand" is considered to be edge 61 of die card, adjacent to open-circuited indexing cells 13 and 16, "right-hand" edge 62 being adjacent to the short-circuited cells 14 and 15. For reading the supplementary data on a card, it makes no difference on which handling strip, 17 or 18, the reading is performed since both contain the same data. This detection employs the same principle used for the reading the credit cell coindition, i.e., a metallized segment will draw power from the sensing coil's circuit due to the induction, by magnetic coupling, of a current on said metallic film. On the absence of metallization, this loss does not take place and the voltage between the terminals of said coil will be significantly larger, as taught on page 13, lines 15 to 19 of patent document BR 9203968-5, among others.

As already mentioned, the existing reading heads comprise only sensors positioned coincidently with the credit cells occupying central region 11 of the card, thus making it necessary to perform the reading of the data on the handling strips before the card has reached its final position within the reading head, that is, while the card is being inserted into the reading head. According to the present invention, the reading is carried out by the row of sensing coils the farthest away from the insertion slot, while the handling strip is passing by said sensors. All that is necessary to carry out such a reading is to change the software of the reading head, avoiding the need for any hardware modification in the reading head.

Figure 4 illustrates several positions of the card along its insertion into the reading head, the corresponding reading process sequence being shown in figure 5.

Taking as the initial state of the telephone set the one in which the set is not in use, the circuit keeps monitoring repeatedly sensors 65-66 which have the function of detecting the presence of an inductive debit card. Figure 4-a shows the condition before the detection, in which card 30 began to be inserted through front slot 69 of the reading head, not having yet reached sensor row 64, the farthest away from said slot. In this figure, the sensors are indicated only by their cylindrical feπite nuclei; as mentioned, sensor row 64 is responsible for the reading of supplementary data on the card.

Figure 4-b shows the condition when the car's front edge 19 has just passed by row 64. In this figure, metallized tracks can be seen under both verifying sensors at positions 65 and 66. On detecting this condition, which is equivalent to "both cells are short-circuited" or "both coikls loaded" (steps 82 and 83 of figure 5), the reading of all sensors of said row 64 is triggered off, the resulting bits being stored in a temporary register for a later interpretation. Next, the reading process moves to step 84 in figure 5, monitoring the two sensor pairs 65-66 and 67-68, i.e., checking the existence of both an open-circuited cell and a short-circuited one in each of said pairs, step 85. This signals that the card has moved to the end of the insertion course within the reading head, as is taught in document

9201380-5. At this moment, it is possible to identify the position of the inserted card, that is, the "right- hand" border and the "left-hand" one since, in the case shown, "left-hand" border 61 is adjacent to the open circuited indexing cells 13 and 16 and the "right-hand" border is adjacent to short-circuited cells 14 and 15. Once this identification is completed, the circuit is able to read, in the correct direction, the bits previously stored, step 87. If this information corresponds to the one considered as valid (relative to the issuing date and issuing country), step 88, the card will be released for use by carrying out the routine already known of counting the available credits and collecting them, according to the number called and the duration of the call, step 89. In the case in which the data resulting from the interpretation of the stored bits is not valid, the card will be rejected, step 91.

Figure 6 shows a second embodiment of the invention in which each handling area is sub-divided into two strips, allowing the quantity of bits mere encoded to be doubled. In this case, on strip 17 there will be a first group of 7 bits, 42, 43 .... 48, and a second group of 7 bits, 42a, 43a .... 48a, separated by a non- metallized strip 72, which, when passing by sensors 65-66, signals the exit of the first group from the reading area and the entrance of the second group in the same reading area. Strip 18a is encoded akin to strip 18 so as to allow the reading of supplementary data independently from the position in which the card was inserted into the reading head.

Claims

C L A I M S

1. SUPPLEMENTARY CODING ON INDUCTIVE DEBIT CARDS allowing for the inclusion of additional information without ' hanging the quantity of credits contained in the card's central area (11), characterizeα by the fact that said information is contained in the handling strips (17, 18) located between said central area and the front edge (19) and rear edge (21) of said card.

2. SUPPLEMENTARY CODING ON INDUCTIVE DEBIT CARDS according to claim 1, characterized by the fact that said additional information is encoded by means of the presence or absence of metallized tracks or segments in said handling strip (17, 18), the presence of metallization (43, 43', 45, 45', 48, 48') corresponding to information bit "1" and the absence of metallization (42, 42', 44, 44', 46, 46', 47, 47') to information bit "0".

3. SUPPLEMENTARY CODING ON INDUCTIVE DEBIT CARDS according to claim 2, characterized by the fact that the number of tracks is the same as the number of cell columns on the card, coinciding the longitudinal axis of each track with the axis (31, 32, .... 39) of each cell column.

4. SUPPLEMENTARY CODING ON INDUCTIVE DEBIT CARDS according to claim 3, characterized by the fact that the four tracks located on the four comers (41, 41', 49, 49') of the card are always metallized.

5. SUPPLEMENTARY CODING ON INDUCTIVE DEBIT CARDS according to claim 3, characterized by the fact that the informations contained on both handling strips (17, 18) are always identical.

6. SUPPLEMENTARY CODING ON INDUCTIVE DEBIT CARDS according to any of the previous claims, characterized by the fact mat each track (41, 41', .... 49, 49') is subdivided into two parts in the card's longitudinal direction.

7. READING PROCESS of supplementarily encoding on inductive debit cards, said encoding being provided by tracks, metallized or not, aligned withthe credit cell columns of the card, characterized by the fact that the detection of d e presence or absence of said metallization be made by the row (64) of sensing coils located the farthest away from the insertion slot (69) through which the card slides into the reading head, during the time said card is being inserted into said head.

8. READING PROCESS according to claim 7, characterized by the fact that the reading of the information is triggered by the detection of the presence of an encoded handling strip (17, 18), at said sensor row (64), said detection taking place when one pair of metallised tracks (41-49), 41 '-49') located at the comers of die card passes by the card position verifying sensing coils (65, 66).

9. READING PROCESS according to the claim 8, characterized by the fact that it comprises the additional steps of:

- storing the bits in a temporary register (83);

- detecting the completion of card insertion (30) into the reading head (85);

- identifying the left-hand edge (61) and the right-hand edge (62) of the card insert¬ ed into the reading head; - interpretation of said temporarily stored bits (87);

- rejection (91) or release of the card for routine and normal credit counting and collecting (89).