US4670405A — Sensor array for toxic gas detection

Claim 1

Independent Claim 157 words

A method for identifying at least one component in a gas sample, comprising the steps of: introducing a gas sample suspected of containing at least one component to an array of sensors for exposure of said component or a derivative thereof to said sensors, said array including plural sensors having differing electrical responses to said at least one component of said derivative thereof dependent on the chemical interaction of said at least one component or said derivative thereof with each of said sensors and also dependent on an operational condition of at least one of said plurality of sensors; changing said operational condition during the exposure of said sensors to the gas sample to provide a plurality of different responses from said at least one sensor, forming a response pattern from the responses of said sensors, and comparing the formed response pattern with a set of previously established response patterns to identify said at least one component.

Claim 2

Independent Claim 157 words

A method for identifying at least one component in a gas sample, comprising the steps of: introducing a gas sample suspected of containing at least one component to an array of sensors for exposure of said component or a derivative thereof to said sensors, said array including plural sensors having differing electrical responses to said at least one component of said derivative thereof dependent on the chemical interaction of said at least one component or said derivative thereof with each of said sensors and also dependent on an operational condition of at least one of said plurality of sensors; changing said operational condition during the exposure of said sensors to the gas sample to provide a plurality of different responses from said at least one sensor, forming a response pattern from the responses of said sensors, and comparing the formed response pattern with a set of previously established response patterns to identify said at least one component.

Claim 3

Dependent Claim 27 words

The method of claim 1 wherein the step of forming the response pattern includes the step of converting a first response pattern to a second response pattern.

Claim 4

Dependent Claim 81 words

The method of claim 1 wherein the step of comparing includes comparing the formed response pattern with a plurality of previously established response patterns, and further includes the step of first eliminating at least one of said plurality of previously established response patterns by comparing an insignificant response of said at least one sensor for one condition with said at least one previously established response pattern having a significant response for said at least one sensor for the same operational condition.

Claim 5

Dependent Claim 44 words

The method of claim 1, wherein the changing of the operational condition is carried out to provide a plurality of responses greater in number than the number of said sensors and not smaller than the number of components to be identified in said gas.

Claim 6

Dependent Claim 57 words

The method of claim 1 wherein the step of forming said response pattern results in at least one response pattern identifiable with a concentration of said at least one component and said step of comparing response patterns provides a comparison of said at least one response pattern with a previously established response pattern for determining said concentration.

Claim 7

Dependent Claim 37 words

The method of claim 1 including the step of providing a portable device including said array of sensors and wherein the formation and comparison of the response pattern are carried out with the device in the field.

Claim 8

Dependent Claim 32 words

The method of claim 1, wherein the total number of components that can be detected is greater than the product of the number of sensors times the number of different operational conditions.

Claim 9

Dependent Claim 184 words

An instrument for indeifying at least one hazardous component in a gas sample, comprising sensing means including an array of sensors, means for introducing to said sensing means a gas sample suspected of containing at least one hazardous component, said array including plural sensors having differing electrical responses to said at least one component or a derivative thereof dependent on the chemical interaction of asid at least one component or a derivative thereof with each of said sensors and also dependent on an operational condition of at least one of said plurality of sensors, means for changing said operational condition during the exposure of said sensors to the gas sample to provide a plurality of different responses from said at least one sensor, means for forming a response pattern from said sensing means upon exposure to said sample, means for providing a plurality of previously established response patterns including a previously established response pattern for identifying said at least one component, and means for comparing the formed response pattern with at least one previously established response pattern to identify said at least one component.

Claim 10

Dependent Claim 184 words

An instrument for indeifying at least one hazardous component in a gas sample, comprising sensing means including an array of sensors, means for introducing to said sensing means a gas sample suspected of containing at least one hazardous component, said array including plural sensors having differing electrical responses to said at least one component or a derivative thereof dependent on the chemical interaction of asid at least one component or a derivative thereof with each of said sensors and also dependent on an operational condition of at least one of said plurality of sensors, means for changing said operational condition during the exposure of said sensors to the gas sample to provide a plurality of different responses from said at least one sensor, means for forming a response pattern from said sensing means upon exposure to said sample, means for providing a plurality of previously established response patterns including a previously established response pattern for identifying said at least one component, and means for comparing the formed response pattern with at least one previously established response pattern to identify said at least one component.

Claim 11

Dependent Claim 32 words

The instrument of claim 8 wherein said array includes a heating filament in addition to said sensors, said heating filament being capable of forming a derivative of said at least one component.

Claim 12

Dependent Claim 29 words

The instrument of claim 8 wherein said array includes four sensors, each of said four sensors having electrical responses differing from those of the others of said four sensors.

Claim 13

Dependent Claim 17 words

The instrument of claim 8 having means for providing electrical power of up to about 2 watts.

Claim 14

Dependent Claim 19 words

The instrument of claim 8 wherein said sensing means includes two different heating filaments and four different electrochemical sensors.

Claim 15

Dependent Claim 28 words

The instrument of claim 8 wherein said forming means includes means for converting a first response pattern to a second response pattern prior to the comparison of patterns.

Claim 16

Dependent Claim 47 words

The instrument of claim 8 wherein said comparing means incudes means for comparing an insignificant response of said at least one sensor for one operational condition with a previously established response pattern having a significant response for said at least one sensor for the same operational condition.

Claim 17

Dependent Claim 20 words

The instrument of claim 8 wherein said changing means comprises means for diverting said sample past a chemically selective filter.

Claim 18

Dependent Claim 25 words

The instrument of claim 8 including programming means for selectively identifying an unknown component or monitoring the concentration of a known component of the gas.

Claim 19

Dependent Claim 22 words

The instrument of claim 16 wherein said programming means includes means for mathematically modifying the responses for sensor calibration and background noise.

Claim 20

Dependent Claim 37 words

The instrument of claim 8 including a carrying case including electrical power means, said array of sensors, said means for forming said response pattern, memory means for storing said previously established response patterns, and said comparison means.

Claim 21

Dependent Claim 15 words

The instrument of claim 18, wherein said power means includes at least one electrical battery.

Claim 22

Dependent Claim 21 words

The instrument of claim 8 wherein said changing means enables said at least one sensor to provide more than one response.

Claim 23

Dependent Claim 14 words

The instrument of claim 20 wherein said sensors include at least one semiconductor sensor.

Claim 24

Dependent Claim 22 words

The instrument of claim 20 wherein said changing means comprises at least one heating filament disposed upstream from said array of sensors.

Claim 25

Dependent Claim 22 words

The instrument of claim 22 wherein said array is arranged with the sensors having the higher responses downstream from the other sensors.

Claim 26

Dependent Claim 40 words

The instrument of claim 20 wherein said changing means enables each of a plurality of said sensors to provide more than one response with the number responses for said array of sensors being greater than the number of said sensors.

Claim 27

Dependent Claim 26 words

The instrument of claim 24 wherein said array of sensors is arranged in a space less than about 8 cm by 15 cm by 8 cm.

Claim 28

Dependent Claim 14 words

The instrument of claim 24 wherein said sensors include a plurality of electrochemical sensors.

Claim 29

Dependent Claim 165 words

An instrument for identifying and estimating the concentrations of a plurality of components in a gas sample, comprising: sensing means including an array of differently selective sensors, means for introducing to said sensing means a gas sample suspected of containing one or more components of a predetermined number of components that are detectable by said array, the number of said sensors being greater than one and fewer than said predetermined number of components, means for forming a multi-channel response pattern from said sensing means upon exposure to said sample, means fo comparing said formed pattern with a set of previously established patterns, said comparing means including means for eliminating those of said previously established response patterns which call for significant signals in those channels in which said formed pattern has no significant signal, and means for processing the remaining ones of said previously established response patterns so as to identify and estimate the concentration of each of said one or more components in said sample.

Claim 30

Dependent Claim 165 words

An instrument for identifying and estimating the concentrations of a plurality of components in a gas sample, comprising: sensing means including an array of differently selective sensors, means for introducing to said sensing means a gas sample suspected of containing one or more components of a predetermined number of components that are detectable by said array, the number of said sensors being greater than one and fewer than said predetermined number of components, means for forming a multi-channel response pattern from said sensing means upon exposure to said sample, means fo comparing said formed pattern with a set of previously established patterns, said comparing means including means for eliminating those of said previously established response patterns which call for significant signals in those channels in which said formed pattern has no significant signal, and means for processing the remaining ones of said previously established response patterns so as to identify and estimate the concentration of each of said one or more components in said sample.

Claim 31

Dependent Claim 51 words

The instrument of claim 27, and further including means for changing an operational condition of said array to provide a plurality of different responses from each of said sensors, said predetermined number of components being greater than the product of the number of sensors times the number of different operational conditions.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1990-06-01	1990-12-01	1991-06-02	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1994-06-01	1994-12-01	1995-06-02	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1998-06-01	1998-12-01	1999-06-02	$7700.00	Window Closed / Lapsed

Sensor array for toxic gas detection

Abstract

Inventors

Bibliographic Details

Claims Analysis

References Cited (Backward Citations)

USPTO Annuity & Maintenance Windows

Assigned Categories & Tags

Assign Category Tag