Vending machines with field-programmable electronic locks

• US 7,495,543 B2
• Filed: 11/24/2004
• Issued: 02/24/2009
• Est. Priority Date: 12/27/2001
• Status: Active Grant

• Current Assignee: Micro Enhanced Technology Incorporated
• Original Assignee: Micro Enhanced Technology Incorporated
• Inventors: Brownfield, Lawrence D., Denison, William D., Silvers, Bradley S.
• Primary Examiner(s): Zimmerman; Brian A
• Assistant Examiner(s): Brown; Vernal U
• Application Number:
  US10/997,500
• Publication Number:
  US 20050088279A1
• Time in Patent Office: 1,553 Days
• Field of Search: 340/5.23, 340/5.9, 340/5.91, 340/5.92, 340/5.6, 340/5.61, 340/5.64, 340/5.63, 340/5.65, 340/5.1, 340/5.2, 340/5.22, 700/237, 705/16, 705/17, 705/18
• US Class Current: 340/5.23
• CPC Class Codes: G07C 2009/00388 code verification carried out according to the challenge/response method
• CPC Class Codes: G07C 2009/00412 the transmitted data signal being encrypted
• CPC Class Codes: G07C 2009/005 whereby the code is a random code
• CPC Class Codes: G07C 2009/00793 by Hertzian waves
• CPC Class Codes: G07C 2009/00849 programming by learning
• CPC Class Codes: G07C 2209/04 Access control involving a hierarchy in access rights
• CPC Class Codes: G07C 9/00309 operated with bidirectional data transmission between data carrier and locks
• CPC Class Codes: G07C 9/00571 operated by interacting with a central unit
• CPC Class Codes: G07C 9/00817 where the code of the lock can be programmed
• CPC Class Codes: G07C 9/00896 specially adapted for particular uses
• CPC Class Codes: G07F 11/62 in which the articles are stored in compartments in fixed receptacles
• CPC Class Codes: G07F 5/26 Interlocks, e.g. for locking the doors of compartments other than that to be used
• CPC Class Codes: G07F 9/001 Interfacing with vending machines using mobile or wearable devices
• CPC Class Codes: G07F 9/002 Vending machines being part of a centrally controlled network of vending machines
• CPC Class Codes: G07F 9/026 for alarm, monitoring and auditing in vending machines or means for indication, e.g. when empty
• CPC Class Codes: H04L 2209/56 Financial cryptography, e.g. electronic payment or e-cash
• CPC Class Codes: H04L 2209/80 Wireless network architectures or network communication protocols for wireless network security H04W12/00
• CPC Class Codes: H04L 9/3226 using a predetermined code, e.g. password, passphrase or PIN network architectures or network communication protocols for supporting authentication of entities using passwords in a packet data network H04L63/083
• CPC Class Codes: H04L 9/3271 using challenge-response
• CPC Class Codes: Y10T 70/7079 Key rotated [e.g., Eurocylinder]

Abstract

A vending machine uses a field-programmable electronic lock that learns a key code from a corresponding electronic key. The electronic lock has a learning process activation device that is accessible when the door of the vending machine is in the open position. Using the learning process activation device, a service person activates the electronic lock to perform a key code learning operation, in which the electronic lock receives a key code transmitted from an electronic key and stores the key code in a non-volatile memory for future access control of the vending machine. Data encryption is employed in the communications between the key and the lock to ensure the security of the communications. A communication device installed in the vending machine for communicating with a home base computer allows the operation of the electronic lock to be remotely controlled for access control and auditing purposes.

Claims

1. A vending machine comprising:

a door openable to access contents of the vending machine;

an electronic lock for unlocking the door of the vending machine, the electronic lock comprising a control circuit including a microcomputer, a non-volatile memory containing computer-executable instructions for performing a decryption operation based on an encryption code, a communication interface for receiving communications, and a learning mode activation device, the microcomputer being programmed to perform steps of receiving a learning mode activation signal from the learning mode activation device and, in response to the learning mode activation signal, receiving a first key code in an encrypted form via the communication interface, performing the decryption operation to decrypt the first key code, and storing the decrypted first key code in the non-volatile memory, wherein the vending machine further includes an electrical switch operable by a mechanical lock operable by an associated mechanical key, wherein the microcomputer of the electronic lock is further programmed to receive a trigger signal from the electrical switch when the microcomputer is set in a learning mode using the learning mode activation device and, in response to the trigger signal, enter an operation mode in which the microcomputer unlocks the door of the vending machine upon receiving a subsequent trigger signal generated by the electrical switch.

2. A vending machine as in claim 1, wherein the data received from the electronic lock include access event data regarding access attempts directed to the electronic lock of the vending machine.

3. An electronic key comprising:

a clock;

a microcomputer;

a wireless communication interface for transmitting and receiving communications over a wireless band;

a non-volatile memory having stored therein a key code, and computer executable instructions for performing an encryption operation based on an encryption code; and

an activation device connected to the microcomputer and operable for generating an activation signal for triggering the microcomputer to initiate a key code transmission operation in which the microprocessor performs the encryption operation to encrypt the key code stored in the non-volatile memory, and the wireless communication interface is used to transmit the encrypted key code;

wherein the microcomputer is programmed to perform a bi-directional challenge-response process during a key transmission operation with an electronic lock on a vending machine using encrypted communications through the wireless communication interface, wherein the key contains a clock data back-up buffer, and wherein the microcomputer is further programmed to read clock data from the clock in response to receiving an activation signal from the activation device, and store the clock data into the clock data backup buffer in the non-volatile memory, and to reset the clock using the clock data stored in the clock data backup buffer when the electronic key is powered up by insertion of a battery.

4. A method of determining accessibility of an electronic lock of a vending machine using an electronic key, comprising:

encrypting, by the electronic key, a first key code together with a timestamp and a random number to form a first encrypted message, the first key code being stored in a memory of the electronic key;

transmitting, by the electronic key, the first encrypted message to the electronic lock;

decrypting, by the electronic lock, the first encrypted message received from the electronic key to extract the first key code;

comparing, by the electronic lock, the extracted first key code with a second key code stored in a memory of the electronic lock;

when the first key code matches the second key code, forming by the electronic lock a second encrypted message by encrypting the first key code together with a lock ID and the random number;

transmitting, by the electronic lock, the second encrypted message to the electronic key;

decrypting, by the electronic key, the second encrypted message to extract the first key code and the lock ID;

encrypting by the electronic key the lock ID with the random number to form a third encrypted message;

transmitting by the electronic key the third encrypted message to the electronic lock;

decrypting by the electronic lock the third encrypted message to extract the lock ID; and

unlocking, by the electronic lock, a door of the vending machine when the lock ID extracted from the third encrypted message is correct.

5. A method of determining accessibility of an electronic lock of a vending machine using an electronic key, comprising:

encrypting, by the electronic key, a first key code together with a timestamp and a random number to form a first encrypted message, the first key code being stored in a memory of the electronic key;

transmitting, by the electronic key, the first encrypted message to the electronic lock;

decrypting, by the electronic lock, the first encrypted message received from the electronic key to extract the first key code;

comparing, by the electronic lock, the extracted first key code with a second key code stored in a memory of the electronic lock;

when the first key code matches the second key code, forming by the electronic lock a second encrypted message by encrypting the first key code together with a lock ID and the random number;

transmitting, by the electronic lock, the second encrypted message to the electronic key;

decrypting, by the electronic key, the second encrypted message to extract the first key code and the lock ID;

comparing by the electronic key the lock ID extracted from the second encrypted message with a list of authorized lock ID'"'"'s stored in the memory of the electronic key;

if the lock ID matches one of the authorized lock ID'"'"'s, encrypting by the electronic key the lock ID and the random number to form a third encrypted message;

transmitting by the electronic key the third encrypted message to the electronic lock;

decrypting, by the electronic lock, the third encrypted message to extract the lock ID; and

unlocking, by the electronic lock, a door of the vending machine when the lock ID extracted from the third encrypted message is correct.

6. A method performed by an electronic key for initialization from power up, comprising:

reading a backup time and date stored in a non-volatile memory;

resetting a clock according to the backup time and date read from the non-volatile memory;

obtaining a reading of a power-up counter;

if the power-up counter reading has reached a pre-set limit, disabling the electronic key; and

if the power-up counter reading has not reached a pre-set limit, incrementing the power-up counter.