Fine particle detector and exhaust gas purification apparatus

Patent metadata

Field	Value
Publication number	US-10850221-B2
Application number	US-201715642401-A
Country	US
Kind code	B2
Filing date	Jul 6, 2017
Priority date	Jul 8, 2016
Publication date	Dec 1, 2020
Grant date	Dec 1, 2020

Abstract

A fine particle detector includes: a casing part configured to accommodate an object to be heated; an electromagnetic wave generating part configured to generate electromagnetic waves of different frequencies; at least one power sensor configured to measure powers, from the casing part, of the electromagnetic waves that have entered into the casing part; and a fine particle detection controlling part configured to determine, based on the powers of the electromagnetic waves of the different frequencies measured by the at least one power sensor, whether an accumulated amount of fine particles accumulated in the object to be heated is greater than or equal to a predetermined accumulated amount.

First claim

What is claimed is:

1. A fine particle detector comprising:
a casing configured to accommodate an object to be heated;
an electromagnetic wave generator configured to generate electromagnetic waves of different frequencies;
at least one power sensor configured to measure powers, from the casing, of the electromagnetic waves that have entered into the casing; and
a fine particle detection controller that is electrically coupled to the at least one power sensor, the fine particle detection controller configured to determine, based on the powers of the electromagnetic waves of the different frequencies measured by the at least one power sensor, whether an accumulated amount of fine particles accumulated in the object to be heated is greater than or equal to a predetermined accumulated amount,
wherein the fine particle detection controller is configured to detect that the accumulated amount of the fine particles accumulated in the object to be heated is greater than or equal to the predetermined accumulated amount in response to detecting that a number of electromagnetic waves whose powers are less than or equal to a predetermined power detected by the at least one power sensor is less than or equal to a predetermined number.

2. The fine particle detector according to claim 1 , wherein the at least one power sensor is a reflection power sensor configured to measure powers of electromagnetic waves reflected in the casing among the electromagnetic waves emitted to the casing from the electromagnetic wave generator.

3. The fine particle detector according to claim 1 , wherein the at least one power sensor is a pass-through power sensor configured to measure powers of electromagnetic waves that have passed through the object to be heated among the electromagnetic waves emitted to the casing from the electromagnetic wave generator.

4. The fine particle detector according to claim 1 ,
wherein the at least one power sensor includes a first power sensor and a second power sensor,
wherein the first power sensor is a reflection power sensor configured to measure powers of electromagnetic waves reflected in the casing among the electromagnetic waves emitted to the casing from the electromagnetic wave generator, and
wherein the second power sensor is a pass-through power sensor configured to measure powers of electromagnetic waves that have passed through the object to be heated among the electromagnetic waves emitted to the casing from the electromagnetic wave generator.

5. The fine particle detector according to claim 1 ,
wherein the electromagnetic wave generator is configured to generate the electromagnetic waves of the different frequencies within a predetermined range.

6. A fine particle detector comprising:
a casing configured to accommodate an object to be heated;
an electromagnetic wave generator configured to generate electromagnetic waves of different frequencies;
at least one power sensor configured to measure powers, from the casing, of the electromagnetic waves that have entered into the casing; and
a fine particle detection controller that is electrically coupled to the at least one power sensor, the fine particle detection controller configured to determine, based on the powers of the electromagnetic waves of the different frequencies measured by the at least one power sensor, whether an accumulated amount of fine particles accumulated in the object to be heated is greater than or equal to a predetermined accumulated amount,
wherein the electromagnetic wave generator is configured to generate the electromagnetic waves of the different frequencies within a predetermined range, and
wherein the fine particle detection controller is configured to detect that the accumulated amount of the fine particles accumulated in the object to be heated is greater than or equal to the predetermined accumulated amount in response to detecting that electromagnetic waves whose powers are greater than or equal to a predetermined power detected by the at least one power sensor are absent.

7. A fine particle detector comprising:
a casing configured to accommodate an object to be heated;
an electromagnetic wave generator configured to generate electromagnetic waves of different frequencies;
at least one power sensor configured to measure powers, from the casing, of the electromagnetic waves that have entered into the casing; and
a fine particle detection controller that is electrically coupled to the at least one power sensor, the fine particle detection controller configured to determine, based on the powers of the electromagnetic waves of the different frequencies measured by the at least one power sensor, whether an accumulated amount of fine particles accumulated in the object to be heated is greater than or equal to a predetermined accumulated amount,
wherein the electromagnetic wave generator is configured to generate the electromagnetic waves of the different frequencies within a predetermined range, and
wherein the fine particle detection controller is configured to detect that the accumulated amount of the fine particles accumulated in the object to be heated is greater than or equal to the predetermined accumulated amount in response to detecting that an integral quantity obtained by frequency-integrating the powers detected by the at least one power sensor is less than or equal to a predetermined value.

8. A fine particle detector comprising:
a casing configured to accommodate an object to be heated;
an electromagnetic wave generator configured to generate electromagnetic waves of different frequencies;
at least one power sensor configured to measure powers, from the casing, of the electromagnetic waves that have entered into the casing; and
a fine particle detection controller that is electrically coupled to the at least one power sensor, the fine particle detection controller configured to determine, based on the powers of the electromagnetic waves of the different frequencies measured by the at least one power sensor, whether an accumulated amount of fine particles accumulated in the object to be heated is greater than or equal to a predetermined accumulated amount,
wherein the electromagnetic wave generator is configured to generate the electromagnetic waves of the different frequencies within a predetermined range, and
wherein the fine particle detection controller is configured to detect that the accumulated amount of the fine particles accumulated in the object to be heated is greater than or equal to the predetermined accumulated amount in response to detecting that an integral quantity obtained by frequency-integrating absolute values of frequency-differential values of the powers detected by the at least one power sensor is less than or equal to a predetermined value.

9. The fine particle detector according to claim 1 , wherein a temperature measure configured to measure a temperature of the casing is provided at the casing.

10. The fine particle detector according to claim 1 , wherein the frequencies of the electromagnetic waves generated in the electromagnetic wave generator are greater than or equal to a minimum resonant frequency in the casing.

11. An exhaust gas purification apparatus, comprising:
the fine particle detector according to claim 1 ; and
a fine particle collector configured to collect the fine particles included in exhaust gas,
wherein in a case where the accumulated amount of the fine particles accumulated in the fine particle collector has reached the predetermined accumulated amount, the fine particle collector is irradiated with a microwave generated in the electromagnetic wave generator.

12. The exhaust gas purification appara

Assignees

• Fujitsu Ltd

Inventors

• Imada Tadahiro
• Motoyoshi Katsusada

Classifications

• F01N11/007 Primary

  the diagnostic devices measuring oxygen or air concentration downstream of the exhaust apparatus · CPC title

• B01D46/84 Primary

  by heating only · CPC title

• B01D53/9495

  Controlling the catalytic process · CPC title

• B01D53/94

  by catalytic processes · CPC title

• B01D46/442

  by measuring the concentration of particles · CPC title