WIRELESS AND BATTERYLESS SENSOR

• US 20090165546A1
• Filed: 12/28/2007
• Published: 07/02/2009
• Est. Priority Date: 12/28/2007
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Qasimi, Mohammed A.J, Dixon, Daniel, Kumar, Sachin, Marsh, Brian J., Cook, James D.
• Granted Patent: US 7,730,772 B2
• Time in Patent Office: Days
• US Class Current: 73/146.500
• CPC Class Codes: B60C 23/0449 Passive transducers, e.g. using surface acoustic waves, backscatter technology or pressure sensitive resonators near field passive transducers B60C23/0428
• CPC Class Codes: B60C 23/0496 Valve stem attachments positioned outside of the tyre chamber

Abstract

A wireless and batteryless pressure sensor apparatus comprises of a SAW sensor and an antenna mounted on a printed circuit board. Optionally, and RFID tag in used in combination with the SAW sensor. A sensor antenna and a RFID antenna can be located on the printed circuit board such that the antennas communicate electrically with the sensor and the RFID device. The sensor can be interrogated utilizing a radio frequency, which is used to excite a SAW crystal inside the sensor. The interrogation signal causes the SAW to resonate wherein a resonant frequency changes with the pressure and temperature that is applied to the sensor. An interrogator can receive a return (echo) signal representing a change in SAW sensor properties (e.g., diaphragm change). A printed circuit board can be mounted on a stainless steel port and overpackaged with standard processes for hermetically sealing the sensor, or sensor and RFID device with at least one antenna.

Claims

1. A wireless and batteryless pressure sensor apparatus, comprising:

a SAW sensor for receiving an interrogating radio frequency (RF) signal wherein a resonant frequency changes with an applied pressure and temperature; and

an antenna connected to said SAW sensor such that said antenna communicates wirelessly with a remote transceiver; and

a sensor package adapted as a base for mounting and containing said SAW sensor package and said antenna.

2. The apparatus of claim 1 wherein said sensor package comprises a sensor diaphragm and a surface acoustic wave sensing element for use in measuring at least one of pressure and temperature.

3. The apparatus of claim 1 wherein said sensor package further comprises a shape that is adaptable for measuring use in at least one of pressure and temperature.

4. The apparatus of claim 1 wherein said package cover comprises a stainless steel port.

5. The apparatus of claim 1 further comprising a RFID tag provided in said sensor package and connected to said antenna, said RFID tag provided to improve transmission range of signals provided by said SAW sensor through said antenna.

6. The apparatus of claim 1 said at least one antenna comprises a flexible printed circuit antenna.

7. The apparatus of claim 1 wherein said sensor diaphragm further comprises an over-mold diaphragm that is located within said package cover.

8. The apparatus of claim 1 wherein said package base comprises a stainless steel port, a flush mount port and each formed from a stainless steel material.

9. The apparatus of claim 1 wherein said apparatus is integrated into a tire, wherein said surface acoustic wave sensor package measures at least one of air pressure and air temperature within a tire.

10. The apparatus of claim 1 wherein said printed circuit board interconnect is mounted in a strap configuration and is strapped on a rim of a tire.

13. The apparatus of claim 1 wherein said package cover comprises a shape that is adaptable for measuring use in at least one of pressure and temperature.

14. The apparatus of claim 1 wherein said package cover comprises a plastic material.

15. The apparatus of claim 1 said package further comprises a stainless steel port.

16. The apparatus of claim 1 said at least one antenna comprises a flexible printed circuit antenna.

11. A wireless and batteryless sensing apparatus, comprising:

a printed circuit board interconnect;

a SAW sensor package including and antennae an mounted on said printed circuit board for receiving an interrogating radio frequency (RF) signals wherein a resonant frequency changes with at least one of pressure and temperature;

an RFID device and antennae mounted on said printed circuit board with said saw sensor package;

at least one antenna respectively bonded to said SAW sensor package and said RFID device such that said at least one antenna communicates electrically with said SAW sensor package and said RFID device and permits wireless and batteryless interrogation by a remote transceiver;

a package base for mounting said printed circuit board interconnect; and

a package cover for hermetically sealing said SAW sensor package and said RFID device to provide pressure sensor data thereof.

12. The apparatus of claim 11 wherein said SAW sensor package further comprises a sensor diaphragm and a surface acoustic wave sensing element for use in measuring at least one of pressure and temperature.

17. A method for wirelessly sensing conditions, comprising:

providing a printed circuit board interconnect having a SAW sensor package for receiving an interrogating radio frequency (RF) signal wherein a resonant frequency changes with an applied pressure and temperature;

providing at least one antenna respectively bonded to said SAW sensor package such that said at least one antenna communicates electrically with said SAW sensor package and permits wireless and batteryless interrogation by a remote transceiver; and

providing a package base for mounting said printed circuit board interconnect and a package cover for hermetically sealing said SAW sensor package.

18. The method of claim 17, further comprising providing an RFID tag for use with said SAW sensor to provide a signal from said SAW sensor to an interrogator.

19. The method of claim 17 wherein said package base is used to sense temperature.

20. The method of claim 17 wherein said printed circuit board interconnect is mounted within the rim of a tire.