Electronic wallet system

BACKGROUND OF THE INVENTION

Field of the Invention

0001The present invention relates to an an electronic wallet system using IC cards storing cash information and an IC card reader/writer for reading data from, and writing data into, the IC card.

Description of the Related Art

0002One example of a system using an IC card with a built-in microprocessor (CPU) and/or a memory is a system using IC cards for storing cash information, as described in an article of a newspaper of Japanese Economic and Industrial Newspaper Company (NIKKEI) issued on December 10, 1993, and in the publications of JP-A-3-92966, JP-A-6-503913, JP-A-5-266273, JP-A-5-94458, and JP-A-1-231451. With this system, shopping and money transfer are possible without having a check or credit card. In buying a thing, an IC card is inserted into a reader/processor terminal at a retail shop so that a remaining money value left in the IC card is displayed. When a password (ID) is entered, the money value used for buying the thing is transferred to the terminal. The retail shop inserts its own IC card into the terminal to transfer a sales money value and deposits it on the account of a bank through an automated-teller machine (ATM). Such settlements may be performed over a telephone.

0003If data necessary for settlements and transactions is recorded in an IC card, data can be distributedly managed among IC cardholders and a cost effective off-line system can be realized. For example, the transactions per day are stored in the IC card of a retail shop, and a sales money value is deposited on a bank account through ATM. In this manner, retail shops and banks are not required to be interconnected on line. Bank POS service interconnecting retail shops and banks 24 hours a day is expensive. If traffic of the on-line process is concentrated during the same time period, a response may often be delayed. Some nations have high line cost and bad line conditions. Large merits can be enjoyed by off-line of IC cards.

0004As different from magnetic cards, it is not easy to copy and forge IC cards. However, an IC card system dealing with cash information is concerned about the following issues. IC card may be stolen from a register of a POS system, or data may be illegally stolen from IC cards.

0005If one register of an IC card POS system is used by a plurality of register clerks, a register clerk may illegally transfer cash information, from an IC card storing cash information of a sales money value at a retail shop, into an IC card of the register clerk. Presently, in a system in which cash is dealt and a plurality of register clerks share one register at a department or gasoline stand, robbery of cash is becoming a serious problem.

0006Damages by robbery of cash at stores open 24 hours a day are increasing.

0007Document WO-A-91 10 971 shows a handling system for information carriers such as credit cards including information storing means such as chip circuits. The essential feature of WO-A-91 10 971 is that a credit card, when not used, is unserviceable. To activate a credit card to a serviceable condition one or more states of authority are introduced in the chip circuit, which are adapted to be read by a transceiver device included in a press copying machine for credit cards. The authority information received is arranged to be indicated at the press copying machine. The press coping operation is also arranged to control the transceiver device such that a signal is transferred to the chip circuit to extinguish the state therein, that is, to deactivate the credit card after authority indication.

0008Document US-A-4 305 059 shows a system for transferring funds in lieu of cash comprising modules for storing electronic money information. The modules each comprise a memory for storing an account balance, a keyboard for manually entering the amount of a transaction and an external connector for interconnecting pairs of modules for funds data transfer. The account balance stored in each module as well as transaction amount is displayed prior to completion of each transaction. Upon approval of the transaction, the account balance stored in the memory of the customer module is debited and funds data are transferred to credit the account balance stored in the memory of the vendor module.

SUMMARY OF THE INVENTION

0009It is an object of the present invention to provide an electronic wallet system easy to use having high security, capable of automatically locking an IC card when it is unloaded from an IC card reader/writer, and automatically unlocking an IC card when loaded.

0010In order to achieve the above objects, the invention provides an electronic wallet system as defined by the independent claims 1, 6, 7, 10.

0011Other objects, features and advantages of the present invention will become apparent from the following detailed description of the embodiments of the invention taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

0012<ul id="ul0001" list-style="none" compact="compact"><li>Fig. 1 shows in block form an embodiment of an electronic wallet system (with an IC card reader/writer having a function of locking an IC card), according to the invention.</li><li>Fig. 2 is a block diagram showing an embodiment of IC card unlock for the electronic wallet system shown in Fig. 1.</li><li>Fig. 3 is a block diagram showing another embodiment of IC card unlock for the electronic wallet system shown in Fig. 1.</li><li>Fig. 4 is a block diagram showing a further embodiment of IC card unlock for the electronic wallet system shown in Fig. 1.</li><li>Fig. 5 shows in block form an embodiment of an electronic wallet system (with a function of locking an IC card), according to the invention.</li><li>Figs. 6A to 6D are timing charts illustrating the operation of the electronic wallet system shown in Fig. 5.</li><li>Fig. 7 shows in block form an embodiment of an electronic wallet system with a non-contact type IC card, according to the invention.</li><li>Fig. 8 shows in block form an embodiment of an electronic wallet system, according to the invention.</li><li>Figs. 9 to 13 show in block form other embodiments of an electronic wallet system, according to the invention.</li><li>Fig. 14 shows in block form an embodiment of an electronic wallet system corresponding to the embodiment shown in Fig. 13, according to the invention.</li><li>Fig. 15 shows in block form an embodiment of an electronic wallet system, according to the invention.</li><li>Fig. 16 shows in block form an embodiment of an electronic wallet system corresponding to the embodiment shown in Fig. 15, according to the invention.</li><li>Fig. 17 shows in block form an embodiment of an electronic wallet system, according to the invention.</li><li>Fig. 18 shows in block form an embodiment of an electronic wallet system corresponding to the embodiment shown in Fig. 17, according to the invention.</li></ul>

DESCRIPTION OF THE PREFERRED EMBODIMENTS

0013Embodiments of the present invention will be described with reference to the accompanying drawings.

0014In this invention, when an IC card is pulled out of an IC card reader/writer, an IC card is automatically locked, and when the IC card is inserted into an IC card reader/writer, the IC card is automatically unlocked.

0015Various embodiments will be described with reference to Figs. 1 to 6 in which an IC card reader/writer is provided with an IC card lock/unlock means.

0016Fig. 1 shows an embodiment of the invention in block form. In this embodiment, when an IC card 2 is pulled out of an IC card reader/writer 1, a control signal for locking the IC card 2 is generated by the IC card reader/writer 1 to automatically lock the IC card 2.

0017Figs. 2 to 4 show other embodiments of the invention. In these embodiments, when an IC card 2 is inserted into an IC card reader/writer 1, a control signal for unlocking the IC card 2 is generated by the IC card reader/writer 1 to automatically unlock the IC card 2.

0018Referring to Fig. 1, reference numeral 1 represents an IC card reader/writer, reference numeral 2 represents an IC card, reference numeral 3 represents a network, reference numeral 4 represents a host computer, reference numeral 11 represents a controller, reference numeral 12 represents a screen of a display unit such as a monitor, reference numeral 13 represents an input unit such as a keyboard and a bar code reader, and reference numeral 14 represents a memory unit. An interface unit 15 includes terminals 151 for supplying a power to an IC card, terminals 152 for supplying control signals such as clocks and a reset signal to the IC card, and terminals 153 for data transfer between the IC card and the IC card reader/writer. A terminal equipment 16 may be any one of a personal computer, a POS terminal, an ATM, a handy terminal, a telephone terminal, a gate terminal, an automatic dispenser terminal, and the like. Reference numeral 17 represents an IC card lock controller, reference numeral 18 represents an IC card unload switch, reference numeral 19 represents an IC card load controller, reference numeral 110 represents an IC card loader, reference numeral 111 represents an AC/DC converter, reference numeral 112 represents a power detector, and reference numeral 113 represents a data save signal generator.

0019In operation, the controller 11 controls the blocks 12, 13, 14, 15, and 16 of the IC card reader/writer 1. Data from the terminal equipment 16 is supplied via the network 3 to the host computer 4 and processed by the computer 4. The IC card is placed on the loader 110 such as an IC card tray or slot of the IC card reader/writer 1. When the user pushes the IC card unload switch 18 to pull the IC card out of the reader/writer 1, the IC card lock controller 17 generates an IC card lock control signal which is supplied via the controller 11 and the data input/output unit 153 of the interface unit 15, to the IC card 2 to lock it. At the same time, the IC card load controller 19 operates to allow the user to pull the IC card out of the IC card loader 110.

0020Even if power interruption occurs, similar to the depression of the IC card unload switch, it is possible to lock the IC card 2 and unload it from the IC card reader/writer 1. Specifically, although the in-circuit power sources for the display unit 11 and input unit 13 lower as the power supply lowers, the in-circuit power sources for the controller 11, memory unit 14, interface unit 15, and other necessary blocks have auxiliary batteries or large capacitors so that even if the power supply is interrupted, the in-circuit power sources lower gently. The AC/DC converter 111 converts an a.c. voltage into a d.c. voltage. The power detector detects whether a predetermined voltage is being supplied.

0021When the predetermined voltage cannot be obtained, the data save signal generator 113 supplies a signal to the controller 11 to save the data in the IC card 2 and IC card reader/writer 1 for preventing destruction of the data. The IC card lock controller 17 generates an IC card control signal which is supplied via the controller 11 and the data input/output unit 153 of the interface unit 15 to the IC card 2 to lock it. The IC card load controller 19 controls to permit unloading the IC card 2 from the IC card loader 110. As described earlier, although the in-circuit power sources for the display unit 11 and input unit 13 lower as the power supply lowers, the in-circuit power sources for the controller 11, memory unit 14, interface unit 15, IC card loader 110, and other necessary blocks have auxiliary batteries or large capacitors so that even if the power supply is interrupted, the in-circuit power sources lower gently. Therefore, it is possible to save data, lock the IC card 2, and unload the IC card 2 from the IC card loader 110.

0022A method of automatically unlocking the IC card will be described, this method being used in combination with the IC card locking method described above and making the IC card reader/writer easy to use.

0023Fig. 2 shows another embodiment of the invention in block form. In this embodiment, when an IC card 2 is loaded into an IC card reader/writer 1, a control signal for unlocking the IC card 2 is generated by the IC card reader/writer 1 to automatically unlock the IC card 2. A mechanical switch 115 is mounted on the IC card loader 110. When the IC card 2 is correctly loaded, the switch 115 turns on so that the IC card unlock controller 117 generates a control signal for unlocking the IC card 2. This control signal is supplied via the controller 11 and the data input/output unit 153 of the interface unit 15 to the IC card to automatically unlock it.

0024Fig. 3 shows another embodiment of the invention in block form. In this embodiment, when an IC card 2 is loaded into an IC card reader/writer 1, a control signal for unlocking the IC card 2 is generated by the IC card reader/writer 1 to automatically unlock the IC card 2. A current detector 116 is connected to the power supply terminals 151 of the interface unit 15, the current detector 116 detects the amplitude of current supplied to the IC card 1. When the IC card 2 is correctly loaded into the IC card loader 110, power is supplied to the IC card 2 from the power supply unit 151 to flow a predetermined quantity of current. As the current detector 116 detects this predetermined quantity of current, the IC card unlock controller 117 generates a control signal for unlocking the IC card 2. This control signal is supplied via the controller 11 and the data input/output unit 153 of the interface unit 15 to the IC card 2 to automatically unlock it.

0025Fig. 4 shows another embodiment of the invention in block form. In this embodiment, when an IC card 2 is loaded into an IC card reader/writer 1, a control signal for unlocking the IC card 2 is generated by the IC card reader/writer 1 to automatically unlock the IC card 2. A reset signal detector 118 is connected to the terminals 152 of the interface unit 15, the terminals 152 being used for inputting clocks, a reset signal, and the like. When the IC card 2 is correctly loaded into the IC card loader 110, power is supplied to the IC card 2 from the power supply unit 151 and the reset signal is supplied from the control signal input unit 152. When the reset signal is inputted, all the operations of the IC card 2 except clock oscillation are temporarily stopped so as not to operate the IC card 2 under an unstable condition of in-circuits of the IC card 2. Input of the reset signal also provides a function of setting initial values to the circuits used by a microcomputer in the IC card 1 (the microcomputer (CPU) of the IC card 2 will be later described with reference to Fig. 5). After the voltage detector 119 recognizes that the in-circuits of the IC card 1 have been stabilized and the reset signal detector 118 detects that the reset signal has been input to the IC card 2, the IC card unlock controller 117 generates a control signal for unlocking the IC card 2. This control signal is supplied via the controller 11 and the data input/output unit 153 of the interface unit 15 to the IC card 2 to automatically unlock it.

0026Another embodiment will be described in which an IC card is provided with an IC card lock/unlock means.

0027Fig. 5 shows an embodiment of the invention in block form. In this embodiment, when an IC card 2 is pulled out of an IC card reader/writer 1, a control signal for locking the IC card 2 is generated by the IC card 2 to automatically lock the IC card 2. Conversely, when an IC card 2 is loaded into the IC card reader/writer 1, a control signal for unlocking the IC card 2 is generated by the IC card 2 to automatically unlock the IC card 2. The IC card 2 includes a ROM unit 21, a CPU (central processing unit) 22, a memory unit 23, and an interface unit 24. Data in the memory unit 23 is transferred to and from the interface unit 15 of the IC card reader/writer 1 via the interface unit 24 and CPU 11.

0028Figs. 6A to 6D show simplified timing charts. Fig. 6A shows a power supply voltage 241 supplied from the IC card reader/writer 1. Fig. 6B shows an in-circuit power source voltage 244 used by the in-circuits of the IC card 2. Fig. 6C shows a detected voltage of a reset signal 245. Fig. 6D shows a signal generated by an IC card lock/unlock controller 26.

0029In a reset circuit for generating the reset signal 245, a reset input 242 gently rises with a time constant determined by a capacitor C1 and a resistor R after power-on. After several seconds after the power-on, CPU 22 judges that the reset input is high level and starts executing a program stored in the ROM unit 21. Upon power-off, charges in the capacitor C1 are discharged quickly through a diode D1.

0030As shown in the timing charts of Figs. 6A to 6D, the low level of the reset 1 signal 245 is generally detected at a voltage of about 0.2 VR (VR in Fig. 6C). As in the case of instantaneous power interruption, if the in-circuit power source voltage of the IC card 2 becomes lower than the rated operation voltage and immediately thereafter the power supply is recovered, then the reset signal cannot be input as indicated by a broken line in Fig. 5C and CPU 22 runs out of order. To solve this, the in-circuit power source voltage 244 is made slower in lowering its voltage than the power supply voltage 241 to the IC card, by using the capacitor C2 and diode D2.

0031The power source voltage detector 25 detects the level of the power supply 241 to the IC card. When Vcc shown in Fig. 6A becomes equal to or lower than a predetermined voltage detection level at (2) shown in Fig. 6D, the reset signal is set to the low level and the IC card lock/unlock controller 26 turns on the lock control signal to lock the IC card 2. When Vcc shown in Fig. 6A becomes larger than the predetermined voltage detection level at (3) and when it is recognized that the reset signal has been inputted (changed from the low level to the high level) at (4), the lock control signal is turned off to release the lock of the IC card 2.

0032Another embodiment of a lock/unlock controller of an IC card will be described in which data transfer between the IC card reader/writer and the IC card is performed in a non-contact way.

0033Fig. 7 shows an embodiment of the invention in block form. This embodiment provides a lock/unlock method for an IC card of the type (non-contact type) that data is transferred in a non-contact way between an IC card reader/writer and the IC card while power is supplied externally to the IC card. If the IC card 2 is at a position remote from the IC card reader/writer 1 by a predetermined distance, a signal for locking the IC card 1 is supplied to automatically lock it. Conversely, if an IC card 2 is at a position nearer to the IC card reader/writer 1 within the predetermined distance, a signal for unlocking the IC card 1 is supplied to automatically unlock it.

0034First, a lock method for an IC card of a non-contact type will be described. Data can be transmitted in a non-contact way through electromagnetic coupling, electromagnetic induction, microwave communications, optical communications, and the like. In transmitting data from the IC card, a CPU 22 controls a modulator unit 29 by using a ROM 21, and the modulated signal is transmitted via a transmitter unit 27 to the IC card reader/writer 1. Data and other signals transmitted from the IC card reader/writer 1 are received by a receiver unit 28 and demodulated by a data demodulator 210. Power externally supplied to the IC card of the non-contact type can be received through electromagnetic induction or other means. A power supply unit 211 generates an in-circuit power source for the IC card 2, a power source voltage detector 25 detects whether a predetermined power source voltage is obtained. If not, a data save signal 214 is supplied to CPU 22 and an instruction of raising transmission power is supplied to CPU 11 from a transmission power-up unit 215. A notice of a lowered power source voltage is displayed on a display unit 216, or may be given by voices. A data transfer end check unit 212 is provided for checking whether a data transfer has been completed, and a data transfer end notice can be displayed on the display unit 216. After it is confirmed that the in-circuit power source voltage of the IC card 2 has been lowered and that the data transfer end check unit 212 indicates a data transfer end, an IC card lock/unlock controller 26 locks the IC card 2.

0035Next, an unlock method for the IC card of a non-contact type will be described. A data transfer start check unit 218 detects a signal representative of a data transfer start (this signal may be replaced by the reset signal) and the power source voltage detector 25 recognizes that the voltage is higher than the predetermined power source voltage. Thereafter, the IC card lock/unlock unit 26 unlocks the IC card. A data transfer notice is displayed on the display unit 216.

0036Next, another embodiment will be described in which the IC card unlock method is improved in security.

0037Fig. 8 shows an embodiment of the invention in block form. In this embodiment, in order to ensure security, three IDs of a user, an IC card reader/writer, and an IC card are verified to unlock the IC card. After the three IDs are verified, the IC card is unlocked. The user is permitted to use only the IC card reader/writer assigned to the user. In locking the IC card, as described with Fig. 1, the IC card 2 is unloaded from the IC card reader/writer 1, and the IC card reader/writer 1 generates an IC card lock control signal to automatically lock the IC card 2.

0038An unlock method illustrated in Fig. 9 will be described. When an IC card 2 is loaded into an IC card reader/writer 1 and a user ID 131 is input from an input unit 13, a verification unit 330 compares, via a controller 11, this user ID with an ID stored in the memory unit 23 of the IC card 2. Verification units 330 and 331 verify an ID 141 of the IC card reader/writer 1 stored in a memory unit 14 of the IC card reader/writer 1, and an ID 231 of the IC card 2 stored in the memory unit 23 of the IC card. If the verification units verify that both the IDs are correct or verifiable, an IC card lock controller 26 unlocks the IC card 2 via CPU 22.

0039Figs. 9 to 11 show an embodiment of this invention in block form. In the embodiment shown in Fig. 8, the user can use only the IC card reader/writer assigned to the user. In the embodiment shown in Figs. 9 to 11, the user can use the IC card at a plurality of IC card readers/writers allowed by a manager. This embodiment makes a manager easy to use the IC card reader/writer.

0040When a manager ID is input from the input unit 13 of the IC card reader/writer 1, a manager ID verification unit 120 verifies whether the manager has a high priority order. If a high priority order manager ID, CPU 22 of the IC card 1 is notified of the high priority order manager ID. A verification unit 333 verifies whether a high priority order manager ID 232 stored in the memory unit 23 matches the high priority order manager ID 132 entered from the input unit 13. If verifiable, the IC card unlock controller 26 unlocks the IC card.

0041In this embodiment, both the IC card reader/writer and the IC card store the manager ID, and are provided with the manager ID verification unit. As an alternative embodiment, only the IC card reader/writer may store the manager ID and be provided with the manager ID verification unit. Also in this case, if the manager ID is verified, the IC card is unlocked.

0042Similarly, only the IC card may store the manager ID and be provided with the manager ID verification unit.

0043Fig. 12 shows another embodiment of the invention in block form. In this embodiment, as shown in Fig. 1, when an IC card 2 is pulled out of an IC card reader/writer 1, a control signal for locking the IC card 2 is generated by the IC card reader/writer 1 to automatically lock the IC card 2. Conversely, as shown in Fig. 2, when an IC card 2 is inserted into an IC card reader/writer 1, a control signal for unlocking the IC card 2 is generated by the IC card reader/writer 1 to automatically unlock the IC card 2.

0044In the embodiment shown in Fig. 12, in order to ensure security, two IDs of the user and IC card reader/writer are verified before unlocking the IC card reader/writer 1. The user can use only the IC card reader/writer assigned to the user. When a user ID is entered from the input unit 13, a verification unit 121 verifies an ID of the IC card reader/writer 1 stored in the memory unit 14. If verifiable, an IC card reader/writer unlock controller 114 outputs an unlock control signal to the controller 11 to unlock the IC card reader/writer 1. After the IC card is unlocked, the user ID entered from the input unit 13 is stored in the memory unit 14 of the IC card reader/writer 1. Therefore, a history of users of the IC card reader/writer can be known.

0045Next, a system will be described in which the IC card lock/unlock method is improved in security. In this system, at the same time when the IC card is locked, a random number is generated to use it as an ID of the IC card.

0046Fig. 13 shows another embodiment of the invention in block form. When an IC card is unloaded from the IC card reader/writer 1, a random number is generated in the IC card 2 and a lock control signal is output to automatically lock the IC card. An unlock method is illustrated in Fig. 13. In order to enhance security, the IC card reader/writer 1 is unlocked after two IDs of the user and the IC card reader/writer 1 are verified. When the IC card reader/writer 1 is unlocked, it outputs an unlock control signal to the IC card 2 to also automatically unlock the IC card 2. A user (register clerk) can use only the IC card reader/writer 1 assigned to the user.

0047First, the lock method for the IC card 2 illustrated in Fig. 13 will be described. When the IC card 2 is unloaded from the IC card reader/writer 1, power supply from the power supply terminals 151 of the interface unit 15 to the IC card 2 is stopped. The IC card 2 is provided with an in-circuit power supply 711 which lowers an in-circuit power source voltage 244 slower than the power supply voltage at 241 of the IC card 2. Similar to the embodiment shown in Fig. 5, when the power source voltage detector 25 detects that the voltage becomes equal to or lower than a predetermined voltage, a random number generator 234 generates a random number. This random number is registered in the memory unit 23 as an ID 231 of the IC card 2. Thereafter, the IC card lock controller 26 outputs a lock control signal to CPU 22 to lock the IC card 2.

0048Fig. 14 illustrates an unlock method corresponding to the lock method illustrated in Fig. 14. An IC card 2 is loaded into the IC card reader/writer 1 and a user ID 131 is entered from the input unit 13. A verification unit 121 verifies the entered user ID 131 and an ID 141 of the IC card reader/writer 1 stored in the memory unit 14. If verifiable, an unlock controller 114 of the IC card reader/writer 1 outputs an unlock control signal to the controller 11 to unlock the IC card reader/writer 1. An unlock control signal for the IC card 1 is also supplied via the controller 11 and data input/output unit 153 to the IC card 2. The IC card unlock controller 26 automatically unlocks the IC card 2.

0049In this manner, the IC card cannot be unlocked if the IC card reader/writer is not assigned and allocated to the user. Even if the IC card is stolen and it is used at a different IC card reader/writer 1, data cannot be obtained from this different IC card reader/writer because ID of the IC card is generated by a random number.

0050Fig. 15 shows another embodiment of the invention in block form. In this embodiment, when an IC card 2 is tried to unload from an IC card reader/writer 1, a random number generator 122 of the IC card reader/writer 1 generates a random number which is supplied to the IC card 2 to use it as an ID of the IC card 2. At this time, an IC card lock signal generator 17 generates a lock control signal to automatically lock the IC card. An unlock method is illustrated in Fig. 15. The IC card reader/writer 1 is unlocked by the user ID, and an ID of the IC card generated previously is sent to the IC card. The IC card 2 then outputs an unlock control signal to automatically unlock the IC card 2. The user can use only the IC card reader/writer 1 assigned to the user.

0051First, the lock method for an IC card illustrated in Fig. 15 will be described. When the IC card 2 is tried to unload from the IC card reader/writer 1 by operating upon the IC card unload switch 18, the random number generator 122 generates a random number. This random number is stored in the memory unit 14 as an ID of the IC card 2. At the same time, the random number is stored as an ID of the IC card 2 in the memory unit 23 of the IC card 1, via the data input/output unit 153. Thereafter, the IC card lock signal generator 17 generates a lock control signal and supplies it via the controller 11 and data input/output unit 153 to CPU 22 to automatically lock the IC card 2.

0052Fig. 16 illustrates an unlock method correspending to the lock method illustrated in Fig. 15. An IC card 2 is loaded into an IC card reader/writer 1 and a user ID 131 is entered from the input unit 13. A verification unit 121 verifies an ID of the IC card reader/writer 1 stored in the memory unit 14. If verifiable, an IC card reader/writer unlock unit 114 outputs an unlock control signal to the controller 11 to unlock the IC card reader/writer 1. At the same time, an ID 143 of the IC card 2 is read from the memory unit 14 and supplied via the controller 11 and data input/output unit 153 to the IC card 2. A verification unit 335 compares an ID 231 of the IC card 2 stored in the memory unit 23 with the ID 143 of the IC card sent from the IC card reader/writer 1. If both the IDs coincide with each other, the IC card unlock controller 26 outputs an unlock control signal to CPU 22 to automatically unlock the IC card 2.

0053A method, by which vandalism by a user (register clerk) of an IC card reader/writer can be prevented and the IC card reader/writer is made easy to use, is illustrated in Figs. 17 and 18. An IC card has a plurality of keys (pass words), a first lock of the IC card is released by a password of a high priority order manager and a random number ID is discarded to allow a register clerk to use its own ID. A second lock is released by the ID of the register clerk to permit a use of the IC card. In this manner, security can be improved and the IC card reader/writer is made easy to use.

0054Fig. 17 illustrates an IC card lock method. When an IC card is unloaded from an IC card reader/writer, a random number is entered as an ID of the IC card to lock it (similar to Fig. 13). In addition to the random number ID, the IC card has a manager ID (highest priority order) and a user ID. These IDs have a higher priority order of a manager ID, a random number ID, and a user ID in this order recited.

0055Fig. 18 illustrates an IC card unlock method corresponding to the method illustrated in Fig. 18. A manager ID 131 is entered from the input unit 13 of an IC card reader/writer 1. If the manager ID is verifiable, a random number ID 231 of the IC card 2 is replaced by a user (register clerk) ID stored in the memory unit. The user (register clerk) can unlock the IC card by using its own ID. With this arrangement, security can be improved, and the IC card reader/writer can be made easy to use.

0056A vandalism preventing system capable of inhibiting a refundment of money larger than a credit money value paid for one transaction.

0057As described above, according to the above embodiments, an electronic wallet system easy to use having high security can be realized.

0058Since an IC card can be automatically locked when it is unloaded from an IC card reader/writer, it is possible to realize an electronic wallet with high security.

0059When an IC card is loaded into an IC card reader/writer, the IC card or IC card reader/writer generates an IC card unlock control signal to automatically unlock the IC card. It is therefore possible to realize an electronic wallet system easy to use.

0060In the embodiments used by an IC card POS system, a register clerk can use only the register assigned to the clerk. Therefore, vandalism of stealing cash information from an IC card can be presented. In an IC card having a plurality of IDs, a manager can use a plurality of registers and the electronic wallet system is made easy to use.

0061If an ID of an IC card is generated by a random number when the IC card is unloaded from a register, security can be improved. In this case, the IC card cannot be unlocked unless another register has the random number ID of the IC card. On the other hand, a manager can unlock the IC card with a random number ID by using an ID of the manager, so that the register can be made easy to use.