System, method, and sensors for sensing physical properties
December 6, 2019. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3338100 3656132 Implantable pressure transducer Electrostatically deformable thin silicon membranes Implantable calibration means and calibration method for an implantable body transducer Digital pressure transducer Pressure detector comprising a cylindrical cavity resonator having a front surface made as a diaphragm Telemetric differential pressure sensing system and method therefore Vibrating accelerometer-multisensor Resonant sensor and method of making same InventorsAssigneeApplicationNo. 454748 filed on 12/06/1999US Classes:340/870.16, Condition responsive73/774, Specified sensor structure324/655, Including a tuned or resonant circuit331/66, Temperature or light responsive340/10.1, Interrogation response340/447, Radio wave340/449, Temperature340/451, Fluid pressure340/521, Plural diverse conditions340/584, Thermal340/665, Force or stress340/870.17, Temperature340/870.28, Via radiant energy beam (via particular energy)340/870.31, Inductive transmitter374/120, In spaced noncontact relationship to specimen374/183, By current modifying sensor374/184, Reactive element (e.g., capacitive)422/82.02Resistance or conductivityExaminersPrimary: Lee, Benjamin C.Attorney, Agent or FirmInternational ClassG08B 021/00AbstractSeveral sensors are provided for determining one of a number of physical roperties including pressure, temperature, chemical species, and other physical conditions. In general, the sensors feature a resonant circuit with an inductor coil which is electromagnetically coupled to a transmitting antenna. When an excitation signal is applied to the antenna, a current is induced in the sensor circuit. This current oscillates at the resonant frequency of the sensor circuit. The resonant frequency and bandwidth of the sensor circuit is determined using an impedance analyzer, a transmitting and receiving antenna system, or a chirp interrogation system. The resonant frequency may further be determined using a simple analog circuit with a transmitter. The sensors are constructed so that either the resonant frequency or bandwidth of the sensor circuit, or both, are made to depend upon the physical properties such as pressure, temperature, presence of a chemical species, or other condition of a specific environment. The physical properties are calculated from the resonant frequency and bandwidth determined.Field of SearchCondition responsiveTemperature Inductive transmitter Insulation Tire deflation or inflation Temperature Fluid pressure Thermal Force or stress Plural diverse conditions With particular coupling link Interrogation response Via radiant energy beam (via particular energy) In spaced noncontact relationship to specimen By current modifying sensor Reactive element (e.g., capacitive) Resistance or conductivity Temperature or light responsive Including a tuned or resonant circuit Specified sensor structure | |
