System and method for inductive power transfer to door
A system and method for a door is disclosed. The system includes a frame magnetic lock assembly mounted to a door frame, and a door magnetic lock assembly mounted to a door for receiving inductively transferred power from the frame magnetic lock assembly. The door system also includes a door electronics subsystem mounted to the door that includes a power management system that provides power to the door from the inductively transferred power, and charges an energy storage element at the door from the inductively transferred power. The power management system provides power to the door from the energy storage element when the inductively transferred power is not available at the door, such as when the door is open, and resumes providing power to the door from the inductively transferred power once the inductively transferred power is restored. Once restored, some of the inductive power recharges the energy storage element.
1. A system for providing power to a magnetic lock system for a door, the system comprising:
a frame magnetic lock assembly mounted to a door frame for the door, the frame magnetic lock assembly including a lock coil and an inductive power transmitter; and
a door magnetic lock assembly mounted to the door, the door magnetic lock assembly comprising an inductive power receiver for receiving inductively transferred power from the inductive power transmitter of the frame magnetic lock assembly, the door magnetic lock assembly including a ferromagnetic plate for locking the door when the lock coil is energized thereby generating a magnetic field to attract the ferromagnetic plate to the lock coil.
2. The system of claim 1 , further comprising a door electronics subsystem mounted to the door that includes:
a power management system that provides power to components of the door from the inductively transferred power;
a power bus that distributes the power from the power management system the components of the door; and
a door controller that is powered by the power bus.
3. The system of claim 2 , further comprising a WiFi transceiver that provides data communication for the door controller and is powered via the power bus.
4. The system of claim 2 , wherein the power management system comprises:
an energy storage element; and
a power conditioning circuit that converts an AC power signal transduced from the inductively transferred power into a door DC power signal and charges the energy storage element with the door DC power signal.
5. The system of claim 1 , wherein the door magnetic lock assembly includes a door position sensor that indicates an open and/or closed state of the door.
6. The system of claim 1 , wherein the frame magnetic lock assembly further comprises a frame communications antenna, connected to a frame communications transceiver, and the door magnetic lock assembly further comprises a door communications antenna, connected to a door communications transceiver, for enabling communications between the door and the door frame.
7. The system of claim 6 , wherein the frame communications transceiver and the door communications transceiver are near field communications (NFC) transceivers.
8. An access control system, comprising:
a door control module for controlling locking and unlocking of a door;
a frame magnetic lock assembly mounted to a door frame for the door, the frame magnetic lock assembly including a lock coil and an inductive power transmitter; and
a door magnetic lock assembly mounted to all the door, the door magnetic lock assembly comprising an inductive power receiver for receiving inductively transferred power from the inductive power transmitter of the frame magnetic lock assembly, the door magnetic lock assembly including a ferromagnetic plate for locking the door when the lock coil is energized thereby generating a magnetic field to attract the ferromagnetic plate to the lock coil.
9. A method for providing power to a magnetic lock system, the method comprising:
receiving, by an inductive power receiver of a door magnetic lock assembly mounted to a door, inductively transferred power from an inductive power transmitter of a frame magnetic lock assembly mounted to a door frame for the door, the door magnetic lock assembly including a. ferromagnetic plate for locking the door when a lock coil of the frame magnetic lock assembly is energized thereby generating a magnetic field to attract the ferromagnetic plate to the lock coil.
10. The method of claim 9 , further comprising providing, by a power management system mounted to the door, power to components of the door from the inductively transferred power.
11. The method of claim 10 , wherein providing power to the components of the door from the inductively transferred power comprises converting an AC power signal transduced from the inductively transferred power into a door DC power signal, and charging an energy storage element on the door with the door DC power signal.
12. The method of claim 11 , further comprising providing power to the components of the door from the energy storage element when the door is open.
13. The method of claim 11 , further comprising providing power to the components of the door from the energy storage element in response to a door control module at the door frame unlocking the door, the door control module unlocking the door by deactivating a DC power unit that supplies power to the frame magnetic lock assembly.
14. The method of claim 11 , further comprising providing power to the components of the door from the energy storage element when the inductively transferred power at the door is absent, and resuming providing power to the components of the door from the inductively transferred power when the inductively transferred power at the door is restored.
15. The method of claim 9 , further comprising a door position sensor sending an indication of an open and/or closed state of the door to a door controller at the door.
16. The method of claim 9 , further comprising enabling communications between the door and the door frame.
17. The system of claim 1 , wherein the frame magnetic lock assembly receives power from a door control module for controlling locking and unlocking of the door.
18. The system of claim 17 , wherein a DC power unit of the door control module provides a DC power signal to power both the lock coil and the inductive power transmitter.
19. The system of claim 18 , wherein the door control module locks the door by activating the DC power unit to enable the DC power signal, resulting in the inductive power transmitter inductively transmitting power to the door magnetic lock assembly via the inductive power receiver.
20. The system of claim 18 , wherein the door control module unlocks the door by deactivating the DC power unit to disable the DC power signal, resulting in neither the lock coil nor the inductive power transmitter receiving the DC power signal and preventing inductive power transfer by the inductive power transmitter when the door is unlocked and/or opened.