US 7,536,920 B2
	Seat occupancy detector
Yves Decoster, Ethe (Belgium)
Assigned to IEE International Electronics & Engineering S.A., (Luxembourg)
Appl. No. 10/579,527 PCT Filed Nov. 12, 2004, PCT No. PCT/EP2004/052950 § 371(c)(1), (2), (4) Date May 15, 2006, PCT Pub. No. WO2005/047067, PCT Pub. Date May 26, 2005.
Claims priority of application No. 03104207 (EP), filed on Nov. 14, 2003.
Prior Publication US 2007/0125586 A1, Jun. 07, 2007
Int. Cl. G01B 7/16 (2006.01); G08B 23/00 (2006.01)

U.S. Cl. 73—781  [340/573.1]

7 Claims

5. Seat occupancy sensor, comprising at least one pressure detection device associated with a surface of a seat and a control unit for communicating with the pressure detection device, wherein said pressure detection device comprises a surface acoustic wave device including at least one surface acoustic wave resonator and an antenna and wherein said control unit comprises an RF antenna for remotely interrogating and communicating with said surface acoustic wave device, wherein said pressure detection device further comprises a dedicated pressure sensor, said dedicated pressure sensor being electrically connected to said surface acoustic wave device so as to activate said surface acoustic wave device when said dedicated pressure sensor is triggered, wherein said dedicated pressure sensor comprises a pressure sensitive switching device, said pressure sensing switching device being electrically connected to said surface acoustic wave device so as to activate said surface acoustic wave device when said pressure sensitive switching device is triggered, and wherein said pressure sensitive switching device is connected in series between the surface acoustic wave resonator and the antenna.