DOOR/WINDOW SENSOR

• US 20190206206A1
• Filed: 01/03/2018
• Published: 07/04/2019
• Est. Priority Date: 01/03/2018
• Status: Active Grant

• Current Assignee: Ademco Inc. (Resideo Technologies, Inc.)
• Original Assignee: Honeywell International Inc.
• Inventors: Smith, Richard Alan
• Granted Patent: US 10,643,440 B2
• Time in Patent Office: Days
• CPC Class Codes: G01R 33/0206 Three-component magnetometers
• CPC Class Codes: G01R 33/0286 comprising microelectromechanical systems [MEMS] MEMS devices in general B81B
• CPC Class Codes: G06K 19/07758 arrangements for adhering the record carrier to further objects or living beings, functioning as an identification tag
• CPC Class Codes: G08B 13/08 by opening, e.g. of door, of window, of drawer, of shutter, of curtain, of blind
• CPC Class Codes: G08B 21/18 Status alarms G08B21/02 takes precedence
• CPC Class Codes: G08B 29/046 prevention of tampering with detection circuits

Abstract

Systems and methods for a door or window contact sensor are provided. Some systems can include a three-dimensional (3D) microelectromechanical system (MEMS) magnetic sensor, a programmable processor, and executable control software stored on a non-transitory computer readable medium, wherein the 3D MEMS magnetic sensor can measure magnetic parameters of a magnetic field along three axes, and wherein the programmable processor and the executable control software can compare the magnetic parameters to reference values to determine whether the magnetic parameters indicate that a door or a window associated with the 3D MEMS magnetic sensor is open or closed.

Claims

1. A system comprising:

a three-dimensional (3D) microelectromechanical system (MEMS) magnetic sensor;

a programmable processor; and

executable control software stored on a non-transitory computer readable medium,

wherein the 3D MEMS magnetic sensor measures magnetic reference values responsive to a powering on event,

wherein the 3D MEMS magnetic sensor measures magnetic parameters of a magnetic field along three axes, and

wherein the programmable processor and the executable control software compare the magnetic parameters to the magnetic reference values to determine whether the magnetic parameters indicate that a door or a window associated with the 3D MEMS magnetic sensor is open or closed.

2. The system of claim 1 wherein the magnetic reference values include first reference values and second reference values.

3. The system of claim 2 wherein the programmable processor and the executable control software identify the first reference values of the magnetic field along the three axes for an open position of the door or the window, and wherein the programmable processor and the executable control software identify the second reference values of the magnetic field along the three axes for a closed position of the door or the window.

4. The system of claim 1 further comprising:

a reference magnet,

wherein the reference magnet generates the magnetic field.

5. The system of claim 4 wherein the reference magnet is mounted on a stationary portion of the door or the window, and wherein the 3D MEMS magnetic sensor is mounted on a moving portion of the door or the window.

6. The system of claim 4 wherein the reference magnet is mounted on a moving portion of the door or the window, and wherein the 3D MEMS magnetic sensor is mounted on a stationary portion of the door or the window.

7. The system of claim 1 wherein the magnetic parameters include magnetic field vectors and magnetic flux density.

8. The system of claim 1 further comprising status communication circuitry that reports an alarm status to a control panel of a security system protecting a secured area in which the door or the window is located.

9. A system comprising:

a three-dimensional (3D) microelectromechanical system (MEMS) magnetic sensor;

a programmable processor; and

executable control software stored on a non-transitory computer readable medium,

wherein the 3D MEMS magnetic sensor measures reference values responsive to a powering on event,

wherein the 3D MEMS magnetic sensor measures magnetic flux magnitudes of a magnetic field along three axes, and

wherein the programmable processor and the executable control software compare the magnetic flux magnitudes to the reference values to determine whether the magnetic flux magnitudes indicate an attempt to defeat.

10. The system of claim 9 wherein the programmable processor and the executable control software identify the reference values along the three axes.

11. The system of claim 9 further comprising:

a reference magnet,

wherein the reference magnet generates the magnetic field.

12. The system of claim 11 wherein the reference magnet is mounted on a stationary portion of a door or a window, and wherein the 3D MEMS magnetic sensor is mounted on a moving portion of the door or the window.

13. The system of claim 11 wherein the reference magnet is mounted on a moving portion of a door or a window, and wherein the 3D MEMS magnetic sensor is mounted on a stationary portion of the door or the window.

14. The system of claim 9 wherein the programmable processor and the executable control software detect the attempt to defeat when one or more of the magnetic flux magnitudes along one or more of the three axes differs from one or more of the reference values.

15. The system of claim 9 further comprising status communication circuitry that reports an alarm status to a control panel of a security system protecting a secured area in which the 3D MEMS magnetic sensor is located.

16. A method comprising:

three-dimensional (3D) microelectromechanical (MEMS) magnetic sensor measuring magnetic reference values of a magnetic field along three axes responsive to a powering on event;

the 3D MEMS magnetic sensor measuring magnetic parameters of the magnetic field along the three axes; and

a processor comparing the magnetic parameters to the magnetic reference values to determine whether the magnetic parameters indicate that a door or a window associated with the 3D MEMS magnetic sensor is open or closed.

17. The method of claim 16 wherein the magnetic reference values include first reference values and second reference values.

18. The method of claim 17 further comprising:

the processor identifying the first reference values of the magnetic field along the three axes for an open position of the door or the window; and

the processor identifying the second reference values of the magnetic field along the three axes for a closed position of the door or the window.

19. The method of claim 18 further comprising:

the 3D MEMS magnetic sensor measuring third reference values;

the 3D MEMS magnetic sensor measuring magnetic flux magnitudes of the magnetic field along the three axes; and

the processor comparing the magnetic flux magnitudes to the third reference values to determine whether the magnetic flux magnitudes indicate an attempt to defeat.

20. The method of claim 16 wherein the magnetic field is generated by a reference magnet.