Arithmetic device, arithmetic method, and gas detection system

Patent metadata

Field	Value
Publication number	US-12066416-B2
Application number	US-202017605543-A
Country	US
Kind code	B2
Filing date	Apr 17, 2020
Priority date	Apr 22, 2019
Publication date	Aug 20, 2024
Grant date	Aug 20, 2024

Abstract

[Object] To provide an arithmetic device, an arithmetic method, and a gas detection system that are capable of easily correcting deterioration over time of a detection element.[Solving Means] The arithmetic device includes a calculation unit. The calculation unit calculates a correction coefficient from a detection element that causes a resonant frequency change by adsorption of gas on the basis of a resonant frequency change amount associated with a humidity change of the detection element in a degraded state and a resonant frequency change amount associated with a humidity change of the detection element in an initial state that was acquired in advance, and corrects the resonant frequency change amount of the detection element in the degraded state by using the correction coefficient.

First claim

The invention claimed is:

1. A gas detection system comprising:
a gas sensor including a detection element that causes a resonant frequency change by adsorption of target gas; and
an arithmetic device including a calculator that calculates a correction coefficient on a basis of a resonant frequency change amount associated with a humidity change of the detection element in a degraded state and a resonant frequency change amount associated with a humidity change of the detection element in an initial state that was acquired in advance, and
corrects the resonant frequency change amount associated with the humidity change of the detection element in the degraded state by using the correction coefficient,
wherein the resonant frequency change amount associated with the humidity change of the detection element in the initial state that was acquired in advance is a resonant frequency change amount associated with the humidity change of the detection element in the initial state that is calculated in advance on the basis of a first resonant frequency detected when a first gas that has been dehumidified and deodorized from the target gas arrives at the detection element in the initial state, a second resonant frequency detected when a second gas that has been deodorized without being dehumidified from the target gas arrives at the detection element in the initial state, and humidity information on the target gas detected by a humidity sensor.

2. The gas detection system according to claim 1 , wherein
the arithmetic device includes a storage that stores the resonant frequency change amount associated with the humidity change of the detection element in the initial state.

3. The gas detection system according to claim 2 , wherein
the storage stores the correction coefficient.

4. The gas detection system according to claim 2 ,
wherein the detection element is provided in a plurality,
wherein each of the plurality of detection elements includes an oscillator, and an adsorption film that is provided on the oscillator and adsorbs the target gas, the respective adsorption films of the plurality of detection elements being of mutually different types, and
wherein the storage stores the resonant frequency change amount associated with the humidity change of each of the plurality of detection elements in the initial state.

5. The gas detection system according to claim 1 , wherein
the arithmetic device includes a determiner that determines a lifetime of the detection element on a basis of a difference between a resonant frequency detected from the detection element in the degraded state to which the first gas has arrived, and a resonant frequency that was detected from the detection element in the initial state to which the first gas has arrived and that was acquired in advance.

6. The gas detection system according to claim 1 , wherein
the gas sensor includes:
a first flow path that includes a dehumidification and deodorization filter disposed therein and that guides the target gas having passed through the dehumidification and deodorization filter to the detection element,
a second flow path that includes a deodorization filter disposed therein and that guides the target gas having passed through the deodorization filter to the detection element, and
a third flow path that directly guides the target gas to the detection element.

7. An arithmetic method executed by a gas detection system, the gas detection system including a gas sensor including a detection element that causes a resonant frequency change by adsorption of target gas and an arithmetic device connected to the gas sensor, the method comprising:
calculating a resonant frequency change amount associated with a humidity change of the detection element in a degraded state;
calculating a correction coefficient on a basis of the resonant frequency change amount associated with the humidity change of the detection element in the degraded state and a resonant frequency change amount associated with a humidity change of the detection element in an initial state that was acquired in advance; and
correcting the resonant frequency change amount associated with the humidity change of the detection element in the degraded state by using the correction coefficient,
wherein the resonant frequency change amount associated with the humidity change of the detection element in the initial state that was acquired in advance is a resonant frequency change amount associated with the humidity change of the detection element in the initial state that is calculated in advance on the basis of a first resonant frequency detected when a first gas that has been dehumidified and deodorized from the target gas arrives at the detection element in the initial state, a second resonant frequency detected when a second gas that has been deodorized without being dehumidified from the target gas arrives at the detection element in the initial state, and humidity information on the target gas detected by a humidity sensor.

8. The arithmetic method according to claim 7 , further comprising determining a lifetime of the detection element on a basis of a difference between the resonant frequency detected from the detection element in the degraded state to which the first gas has arrived, and the resonant frequency detected from the detection element in the initial state to which the first gas has arrived that was acquired in advance.

Assignees

• Taiyo Yuden Kk

Inventors

• Hattori Masashi
• Shimomai Kenichi
• Onda Yosuke

Classifications

• G01N5/02

  by absorbing or adsorbing components of a material and determining change of weight of the adsorbent, e.g. determining moisture content {(absorption bulbs B01D53/00)} · CPC title

• G01N2291/106

  one or more transducer arrays · CPC title

• G01N2291/0256

  Adsorption, desorption, surface mass change, e.g. on biosensors · CPC title

• G01N2291/0215

  Mixtures of three or more gases, e.g. air · CPC title

• G01N29/222

  Constructional or flow details for analysing fluids (optoacoustic fluid cells G01N29/2425) · CPC title