Lock control system, lock controller, and key device

• US 7,158,007 B2
• Filed: 06/30/2004
• Issued: 01/02/2007
• Est. Priority Date: 07/25/2003
• Status: Active Grant

• Current Assignee: OKI Electric Industry Company Limited
• Original Assignee: OKI Electric Industry Company Limited
• Inventors: Kawamoto, Yasutaka
• Primary Examiner(s): Zimmerman; Brian
• Assistant Examiner(s): BROWN, VERNAL U
• Application Number:
  US10/879,232
• Publication Number:
  US 20050017839A1
• Time in Patent Office: 916 Days
• Field of Search: 340/5.64, 340/5.1, 340/5.2, 340/5.6, 340/540, 340/541, 340/542, 340/825.69, 340/825.72, 340/10.1, 235/382
• US Class Current: 340/5.64
• CPC Class Codes: G07C 9/00182 operated with unidirectional data transmission between data carrier and locks

Abstract

A lock is operated by a lock controller that receives identifying signals transmitted from one or more wireless key devices. Weights are assigned to the identifying signals, and the lock is operated only if the weights of the received identifying signals satisfy a condition, such as a threshold condition applied to their sum. The weights are preferably assigned by counting the number of times each identifying signal is registered in the lock controller. The count may be kept in the lock controller or in the wireless key device itself.

Claims

1. A lock control system comprising:

a lock having a locked state and an unlocked state;

a plurality of key devices operable to transmit respective unique signals;

a receiver operable to receive the unique signal transmitted by each said key device;

a weight memory operable to register each received unique signal by storing a weight indicating the importance of each unique signal;

an authentication unit operable to read, from said weight memory, the weight of each received unique signal, operable to calculate a sum of the read weights, and operable to determine whether an authentication passes or fails based on the sum of the weights; and

a lock operating unit operable to change said lock from the locked state to the unlocked state, or from the unlocked state to the locked state, if said authentication unit determines that the authentication passes.

2. The lock control system of claim 1, wherein said authentication unit is operable to determine that the authentication fails if only one unique signal is received by said receiver.

3. The lock control system of claim 1, wherein the unique signal is registered by manual input.

4. The lock control system of claim 1, wherein the unique signal is registered automatically via a communication link.

5. The lock control system of claim 1, wherein:

at least one set of key devices in said plurality of key devices is assigned a cumulative weight and said authentication unit is operable to determine that the authentication passes if said receiver receives unique signals from all key devices in the set of keys, and that the authentication fails if said receiver receives unique signals only from a subset of the key devices in the set of key devices; and

another key device in said plurality of key devices is assigned a weight such that said another key device is still operable to pass authentication in the event of the absence of any key device in the set of key devices.

6. A lock control system comprising:

a lock having a locked state and an unlocked state;

at least one key device operable to transmit a unique signal;

a receiver operable to receive the unique signal transmitted by each said key device;

a weight memory operable to register each received unique signal by storing a weight indicating the importance of each unique signal;

a registration count memory operable to store a cumulative registration count corresponding to each unique signal so as to indicate the number of times each unique signal has been registered, wherein the weight stored in said weight memory for each unique signal corresponds to the registration count of each unique signal;

an authentication unit operable to read, from said weight memory, the weight of each received unique signal, operable to calculate a sum of the read weights, and operable to determine whether an authentication passes or fails based on the sum of the weights; and

a lock operating unit operable to change said lock from the locked state to the unlocked state, or from the unlocked state to the locked state, if said authentication unit determines that the authentication passes.

7. The lock control system of claim 6, further comprising a weight calculation unit operable to compare each cumulative registration count stored in said registration count memory with at least one threshold value so as to calculate the corresponding weight of each unique signal stored in said weight memory.

8. A lock control system comprising:

a lock having a locked state and an unlocked state;

at least one key device operable to transmit a unique signal;

a receiver operable to receive the unique signal transmitted by each said key device;

a weight memory operable to register each received unique signal by storing a weight indicating the importance of each unique signal;

an authentication unit operable to read, from said weight memory, the weight of each received unique signal, operable to calculate a sum of the read weights, and operable to determine whether an authentication passes or fails based on the sum of the weights of the unique signal, wherein said authentication unit is operable to determine that the authentication passes if the sum of the read weights of all the received unique signals is equal to or greater than a predetermined fraction of a sum of all the weights stored in said weight memory; and

a lock operating unit operable to change said lock from the locked state to the unlocked state, or from the unlocked state to the locked state, if said authentication unit determines that the authentication passes.

9. A lock control system comprising:

a lock having a locked state and an unlocked state;

at least one key device operable to transmit a unique signal;

a receiver operable to receive the unique signal transmitted by each said key device;

a weight memory operable to register each received unique signal by storing a weight indicating the importance of each unique signal, wherein the weight of each unique signal stored in said weight memory is updated each time the corresponding unique signal is registered so as to indicate the importance of each unique signal;

an authentication unit operable to read, from said weight memory, the weight of each received unique signal, operable to calculate a sum of the read weights, and operable to determine whether an authentication passes or fails based on the sum of the weights; and

a lock operating unit operable to change said lock from the locked state to the unlocked state, or from the unlocked state to the locked state, if said authentication unit determines that the authentication passes.

10. A lock controller for controlling the state of a lock according to a plurality of unique signals transmitted by respective key devices, the lock controller comprising:

a receiver operable to receive the plurality of unique signals;

a weight memory operable to register each received unique signal among the plurality of received unique signals by storing a weight indicating the importance of each unique signal;

an authentication unit operable to read, from said weight memory, the weight of each received unique signal, operable to calculate a sum of the read weights, and operable to determine whether an authentication passes or fails based on the sum of the weights; and

a lock operating unit operable to change the lock from the locked state to the unlocked state, or from the unlocked state to the locked state, if said authentication unit determines that the authentication passes.

11. The lock controller of claim 10, further comprising a registration count memory operable to store a cumulative registration count corresponding to each unique signal so as to indicate the number of times each unique signal has been registered, wherein the weight stored in said weight memory for each unique signal corresponds to the registration count of each unique signal.

12. The lock controller of claim 11, further comprising a weight calculation unit operable to compare each cumulative registration count stored in said registration count memory with at least one threshold value so as to calculate the corresponding weight of each unique signal stored in said weight memory.

13. The lock controller of claim 10, wherein said authentication unit is operable to determine that the authentication passes if a sum of the read weights of all received unique signals is equal to or greater than a predetermined fraction of a sum of all the weights stored in said weight memory.

14. The lock controller of claim 10, wherein said authentication unit is operable to determine that the authentication fails if only one unique signal is received by said receiver.

15. The lock controller of claim 10, wherein the unique signal is registered by manual input.

16. The lock controller of claim 10, wherein the unique signal is registered automatically via a communication link.

17. The lock controller of claim 10, wherein the weight of each unique signal stored in said weight memory is updated each time the corresponding unique signal is registered so as to indicate the importance of each unique signal.

18. The lock controller of claim 10, wherein:

at least one set of key devices in said plurality of key devices is assigned a cumulative weight and said authentication unit is operable to determine that the authentication passes if said receiver receives unique signals from all key devices in the set of keys, and that the authentication fails if said receiver receives unique signals only from a subset of the key devices in the set of key devices; and

another key device in said plurality of key devices is assigned a weight such that said another key device is still operable to pass authentication in the event of the absence of any one key device in the set of key devices.

19. A key device comprising:

a unique signal memory operable to store a signal unique to the key device;

a registration detector operable to detect whether the signal unique to the key device has been registered in a lock controller;

a counter operable to maintain a cumulative count indicating the number of times said registration detector detects that the signal unique to the key device has been registered;

a registration count memory operable to store the cumulative count maintained by said counter; and

a transmitter operable to transmit the signal stored in said unique signal memory and the cumulative count stored in said registration count memory to the lock controller.

20. The key device of claim 19, wherein the key device is operable to calculate a weight according to the cumulative count stored in said registration count memory, and said transmitter is operable to transmit the weight and the signal stored in said unique signal memory to the lock controller.