Wireless door lock power transfer system having communications capabilities

• US 9,673,868 B2
• Filed: 05/15/2014
• Issued: 06/06/2017
• Est. Priority Date: 05/16/2013
• Status: Active Grant

• Current Assignee: Microchip Technology Incorporated
• Original Assignee: Microchip Technology Incorporated
• Inventors: Curtis, Keith
• Primary Examiner(s): PELTON, NATHANIEL R
• Application Number:
  US14/278,420
• Publication Number:
  US 20140340032A1
• Time in Patent Office: 1,118 Days
• Field of Search: 320108
• CPC Class Codes: E05B 2047/0061 using induction
• CPC Class Codes: E05B 47/0001 with electric actuators; Constructional features thereof for vehicles E05B81/04
• CPC Class Codes: G07C 2009/00634 Power supply for the lock
• CPC Class Codes: G07C 2009/00777 by induction
• CPC Class Codes: G07C 2009/00809 with data transmission through the human body
• CPC Class Codes: G07C 9/00174 Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys mechanical locks with electric permutation E05B49/00; arrangements for sensing or reading record carriers G06K7/00; electronic switching H03K17/00
• CPC Class Codes: G07C 9/00309 operated with bidirectional data transmission between data carrier and locks
• CPC Class Codes: G07C 9/00944 Details of construction or manufacture
• CPC Class Codes: H01F 2038/146 in combination with capacitive coupling
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/05 using capacitive coupling
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

A door frame has a first electromagnetic coil and a door lock has a second electromagnetic coil with a door bolt electromagnetically coupling together the first and second electromagnetic coils, thereby forming a transformer. Power is transferred from the door frame to door lock through the transformer. Communications from the door frame to the door lock may be provided by modulating electromagnetic energy to the first electromagnetic coil and demodulating the modulated electromagnetic energy received at the second electromagnetic coil. Communications from the door lock to the door frame may be provided by varying a load on the second electromagnetic coil and detecting the load change at the first electromagnetic coil.

Claims

1. An apparatus for transferring power wirelessly to a door lock, comprising:

a first electric inductor shaped as a coil, adapted to receive a first portion of a door locking bolt and installed in a door frame;

a power transmitter having an alternating current (AC) output coupled to the first electric inductor and an input coupled to a first power source;

a second electric inductor shaped as a coil that surrounds the door locking bolt and is installed in a door;

a power receiver having an input coupled to the second electric inductor and an output for providing a second power source; and

a door frame transceiver and a door transceiver for communicating between the door frame and the door, wherein;

the door frame transceiver is coupled to the power transmitter and modulates the AC output thereof for reception by the door transceiver through the second inductor; and

the door transceiver is coupled to the power receiver, wherein the power receiver modulates a load on the second inductor that is detected by the door frame transceiver through the first inductor.

2. The apparatus according to claim 1, further comprising a power storage device coupled to the output of the power receiver.

3. The apparatus according to claim 2, wherein the power storage device is a rechargeable battery.

4. The apparatus according to claim 2, wherein the power storage device is a super capacitor.

5. The apparatus according to claim 1, wherein the door frame and door transceivers communicate with at least one wireless signal conveying data therebetween.

6. The apparatus according to claim 5, wherein the wireless signal is selected from the group consisting of Bluetooth®

, Wi-Fi®

, ZigBee®

, IRDA, InfraRed, and Ultrasonic.

7. The apparatus according to claim 5, wherein the wireless signal is formatted in accordance with at least one communications standard selected from the group consisting of Bluetooth®

, Wi-Fi®

, and Zigbee®

.

8. The apparatus according to claim 1, further comprising:

a door frame digital processor coupled to the door frame transceiver and the power transmitter, and

a door digital processor coupled to the door transceiver and the power receiver.

9. The apparatus according to claim 1, wherein the door locking bolt is selected from the group consisting of a magnetic metal, a plurality of magnetic metal plates insulated from one another, ferrite impregnated epoxy molded into a door bolt shape.

10. The apparatus according to claim 1, wherein the door locking bolt is a quartz crystal core surrounded by a metal sleeve that resonantly couples power from the first electric inductor to the second electric conductor.

11. The apparatus according to claim 1, wherein power is transferred through capacitive coupling between the door frame and the door.

12. The apparatus according to claim 1, wherein power is transferred from the first electric inductor to the second electric conductor acting as an air core transformer.

13. The apparatus according to claim 8, further comprising a coded unlocking device coupled to the door digital processor.

14. The apparatus according to claim 13, wherein the coded unlocking device is a key card and key card reader in the door.

15. The apparatus according to claim 13, wherein the coded unlocking device is a receiver:

configured to receive signals from a human-based transmitter;

coupled to a handle or knob of the door; and

adapted to receive a human-based transmitter signal when the handle or knob is touched by a person with the human-based transmitter having a corresponding access code for the door lock.

16. The apparatus according to claim 8, further comprising heat sensors on each side of the door, wherein the heat sensors are coupled to the door digital processor and provide surface temperatures of each side of the door.

17. The apparatus according to claim 16, wherein the door digital processor causes a door handle or knob to vibrate if the surface temperature on the opposite side of the door is above a certain temperature.

18. The apparatus according to claim 8, further comprising a door handle or knob position sensor coupled to the door digital processor for indicating positions of the door handle or knob.

19. The apparatus according to claim 18, wherein the door unlocks to open and then relocks upon closing when the door handle or knob is rotated in a first direction, and the door unlocks to open and remains unlocked upon closing when the door handle or knob is rotated in a second direction.

20. The apparatus according to claim 18, wherein the door unlocks when the door handle or knob is rotated in a correct sequential combination of positions and directions.

21. The apparatus according to claim 8, wherein the door frame and door digital processors are microcontrollers.

22. A wireless door lock power transfer system, said system comprising:

a first circuit arranged within a door frame and comprising;

a first coil,

a power driver coupled with the first coil operable to transmit power and to transmit and receive data via said first coil, and

a first microcontroller coupled with said power driver; and

a second circuit arranged within a door and comprising;

a bolt operable to engage with said door frame and further operable to be received within said first coil when engaging with said door frame,

a second coil surrounding said bolt on a door side,

a receiving unit coupled with said second coil operable to receive power and to receive and transmit data via said second coil, and

a second microcontroller coupled with said receiving unit, wherein the receiving unit provides a supply voltage to said second microcontroller when said second coil receives a carrier signal transmitted by said first coil via said bolt.

23. The system according to claim 22, wherein the second circuit further comprises a power voltage supply system controlled by said second microcontroller for providing a power supply voltage.

24. The system according to claim 23, wherein the second circuit further comprises a driving unit operable to move said bolt into and output of said door frame for locking and unlocking said door, wherein the driving unit is coupled with said power supply voltage system.

25. The system according to claim 24, further comprising a plurality of bolts at a plurality of locations around said door proximate to said door frame and operable to move said plurality of bolts.

26. The system according to claim 23, wherein the power voltage supply system is a switched mode power supply controlled by said second microcontroller.

27. The system according to claim 22, wherein the receiving unit modulates loading of said second coil for transmitting data from said second circuit to said first circuit.

28. The system according to claim 22, wherein the power driver modulates the transmitted power to said first coil for transmitting data from said first circuit to said second circuit.

29. A method for transferring power wirelessly to a door lock, said method comprising:

transmitting electromagnetic energy from a power transmitter proximate to a door frame through a door bolt to a power receiver in a door, wherein the power transmitter is coupled to a first electromagnetic coil surrounding a first portion of the door bolt and the power receiver is coupled to a second electromagnetic coil surrounding a second portion of the door bolt;

communicating between the door frame and door through the power transmitter and power receiver, including;

modulating the electromagnetic energy with the power transmitter;

demodulating the electromagnetic energy with the power receiver;

varying a load coupled to the second electromagnetic coil with the power receiver; and

detecting variations of the load coupled between the second and first electromagnetic coils with the power transmitter.