# US 2014/0371619 A1 · Gas sensor with heater > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0371619 A1 - Document ID: US20140371619A1 - Status: Published application - Kind: A1 - Application number: 14/304,359 - Filed: 2014-06-13 - Published: 2014-12-18 - Earliest claimed: 2013-06-13 - Assignees: GM Nameplate, Inc. - Inventors: Steven A. Rodriguez - Web page: https://patentgrep.com/patent/US20140371619A1 ## CPC - A61B 5/082: {Evaluation by breath analysis, e.g. determination of the chemical composition of exhaled breath (A61B5/083, A61B5/091 take precedence)} - A61B 2560/0266: for monitoring or limiting apparatus function - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A first embodiment of a disclosed breath analyzer detects a particular breath component in a breath sample. The analyzer includes a housing defining an interior cavity and having an inlet aperture for receiving the breath sample and an outlet aperture. A sensor is disposed within the cavity for sensing the component of the breath sample. An anemometer circuit is associated with the sensor and measures a rate of flow of the breath sample within the housing. The analyzer further includes a controller operatively connected to the sensor to receive breath component information sensed by the sensor. ## Claims ### Claim 1 A breath analyzer for detecting a component in a breath sample, the analyzer comprising: (a) a housing defining an interior cavity, the housing comprising an inlet aperture for receiving the breath sample and an outlet aperture; (b) a sensor disposed within the cavity for sensing the component of the breath sample; (c) an anemometer circuit associated with the sensor, the anemometer circuit measuring a rate of flow of the breath sample within the housing; and (d) a controller operatively connected to the sensor to receive breath component information sensed by the sensor. ### Claim 2 (depends on 1) The breath analyzer of claim 1, wherein the anemometer circuit comprises a temperature control system integrally formed with the sensor, the temperature control comprising a resistive temperature device configured to heat the sensor to a predetermined temperature and to sense the temperature of the sensor ### Claim 3 (depends on 2) The breath analyzer of claim 2, wherein the sensor comprises a metal oxide deposited on a substrate. ### Claim 4 (depends on 3) The breath analyzer of claim 3, wherein the metal oxide comprises tungsten trioxide. ### Claim 5 (depends on 3) The breath analyzer of claim 3, wherein the substrate comprises aluminum oxide. ### Claim 6 (depends on 3) The breath analyzer of claim 3, wherein the temperature control system comprises a platinum metallization deposited on the substrate. ### Claim 7 (depends on 6) The breath analyzer of claim 6, wherein the metal oxide is deposited on a first side of the substrate and the platinum metallization is deposited on a second side of the substrate. ### Claim 8 (depends on 2) The breath analyzer of claim 2, wherein the temperature control system comprises a closed-loop control circuit selectively controlling the resistive temperature device. ### Claim 9 (depends on 8) The breath analyzer of claim 8, wherein the control circuit comprises a bridge circuit operably connected to an operational amplifier. ### Claim 10 (depends on 9) The breath analyzer of claim 9, wherein the bridge circuit comprises four resistors, the resistive temperature device acting as one of the resistors. ### Claim 11 (depends on 8) The breath analyzer of claim 8, wherein the control circuit comprises a processor controlling a resistive divider, resistive divider comprising the resistive temperature device connected in series with a shunt resistor. ### Claim 12 (depends on 11) The breath analyzer of claim 11, wherein the processor controls the voltage provided to the resistive divider according to a voltage drop across the resistive divider. ### Claim 13 A breath analyzer for detecting a component in a breath sample, the analyzer comprising: (a) a housing defining an interior cavity, the housing comprising an inlet aperture for receiving the breath sample and an outlet aperture; (b) a metal oxide sensor disposed within the cavity for sensing the component of the breath sample; (c) a temperature control system integrally formed with the sensor, the temperature control system comprising a metal resistor having a positive temperature coefficient, the metal resistor being configured to heat the sensor to a predetermined temperature and to sense the temperature of the sensor, wherein a closed-loop control circuit selectively controls the metal resistor, the metal resistor being integrally formed with the closed-loop control circuit, the closed-loop control circuit being configured to measure a rate of flow of the breath sample within the housing; and (d) a controller operatively connected to the sensor to receive breath component information sensed by the sensor. ### Claim 14 (depends on 13) The breath analyzer of claim 13, wherein the control circuit comprises a bridge circuit operably connected to an operational amplifier. ### Claim 15 (depends on 14) The breath analyzer of claim 14, wherein the bridge circuit comprises four resistors, the metal resistor acting as one of the resistors. ### Claim 16 (depends on 13) The breath analyzer of claim 13, wherein the control circuit comprises a processor controlling a resistive divider, resistive divider comprising the metal resistor connected in series with a shunt resistor. ### Claim 17 (depends on 16) The breath analyzer of claim 16, wherein the processor controls the voltage provided to the resistive divider according to a voltage drop across the resistive divider.