Gas sensor

Patent metadata

Field	Value
Publication number	US-10228338-B2
Application number	US-201715429443-A
Country	US
Kind code	B2
Filing date	Feb 10, 2017
Priority date	Feb 10, 2016
Publication date	Mar 12, 2019
Grant date	Mar 12, 2019

Abstract

A measuring device for determining a gas concentration includes a gas-sensitive element, a sensing device, a stimulation unit, and a processing unit. The gas-sensitive element is configured to absorb a gas. The sensing device is configured to determine a parameter of the gas-sensitive element in a predetermined time period, where the parameter depends on an absorbed quantity of the gas. The stimulation unit is configured to stimulate the gas-sensitive element and accelerate desorption of the gas out of the gas-sensitive element. The processing unit is configured to determine a rate of change of the parameter, to control the stimulation such that a concentration of the gas in the gas-sensitive element lies outside of an equilibrium state, and to determine the gas concentration based on the rate of change.

First claim

What is claimed is:

1. A method of determining a gas concentration, comprising:
using a gas-sensitive element to absorb a gas;
determining a rate of change within a predetermined time period of a parameter of the element that depends on a quantity of gas absorbed by the element;
stimulating the element to accelerate desorption of the gas out from the element, such that a concentration of the gas in the element lies outside of an equilibrium state; and
determining the gas concentration based on the rate of change.

2. The method of claim 1 , wherein the stimulating is performed periodically to keep the concentration of the gas in the element within a predetermined range.

3. The method of claim 2 , wherein the gas concentration is determined at least in part based on the rate of change immediately after the stimulating has concluded.

4. The method of claim 1 , wherein the gas concentration is determined with reference to a relationship defined by the equation:

K
=

A
·

(

dR
dt

)

B

where K is the gas concentration, R is the parameter, B is a constant value equal to about 2, and A is a constant value.

5. The method of claim 1 , further comprising determining the parameter electrically.

6. The method of claim 1 , wherein the stimulating includes a heating process.

7. The method of claim 1 , wherein the stimulating includes an irradiation process using a light having a predetermined wavelength.

8. The method of claim 1 , wherein the stimulating includes applying an electric field.

9. A measuring device for determining a gas concentration, comprising:
a gas-sensitive element configured to absorb a gas;
a sensing device configured to determine a parameter of the element, the parameter depending on a quantity of the gas absorbed by the gas-sensitive element;
a stimulation unit configured to stimulate the element in order to accelerate desorption of the gas out from the gas-sensitive element; and
a processing unit configured to:
determine a rate of change of the parameter in a predetermined time period;
control the stimulation unit such that a concentration of the gas in the gas-sensitive element lies outside of an equilibrium state; and
determine the gas concentration with reference to the rate of change.

10. The measuring device of claim 9 , wherein the gas-sensitive element includes a metal oxide.

Assignees

• Bosch Gmbh Robert

Inventors

• Petersen Andreas
• Krauss Andreas
• Badeja Michael

Classifications

• B01L5/00

  Gas handling apparatus (gas jars or cylinders B01L3/12; cold traps or cold baffles B01D8/00) · CPC title

• G01N2001/2244

  Exhaled gas, e.g. alcohol detecting · CPC title

• G01N27/125 Primary

  Composition of the body, e.g. the composition of its sensitive layer · CPC title

• Y02A50/247

  Cross-Sectional Technologies · mapped topic

• G01N2015/0026

  in gas, e.g. fog · CPC title