Leak-Detection Device, Program, and Control Method

• US 20150211953A1
• Filed: 09/06/2013
• Published: 07/30/2015
• Est. Priority Date: 09/28/2012
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Shinoda, Shigeki, Yoshinari, Tetsuya, Yamamoto, Hiromi, Takahashi, Masatake, Sasaki, Yasuhiro, Kinoshita, Shohei
• Granted Patent: US 9,739,684 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01M 3/16 using electric detection means G01M3/045, G01M3/06, G01M3/12, G01M3/20, G01M3/24, G01M3/26 take precedence
• CPC Class Codes: G01M 3/243 for pipes

Abstract

A signal acquisition unit (2020) acquires a signal. From the signal acquired by the signal acquisition unit (2020), a detection signal extraction unit (2060) extracts, as a detection signal, a signal of any frequency band among a plurality of partial detection frequency bands into which the frequency band that is the subject of detection has been divided. A determination unit (2070) determines, in order, for each detection signal corresponding to each of the different partial detection frequency bands, whether the detection signal shows any leakage, and if at least a prescribed number of the detection signals are not showing any leakage, determines that leakage is not taking place.

Claims

1. A leak inspection device comprising:

signal acquisition unit that acquires a signal;

inspection signal extraction unit that extracts, as an inspection signal, a signal in any of a plurality of partial inspection frequency bands obtained by dividing a frequency band as an inspection target, from the signal acquired by the signal acquisition unit; and

determination for unit that sequentially determines whether the inspection signals corresponding to the partial inspection frequency bands which are different from one another indicate a leak or not and, when predetermined number or more of the inspection signals do not indicate a leak, determining that there is no leak.

2. The leak inspection device according to claim 1, wherein the determination unit includes:

partial determination unit that determines whether the inspection signal corresponding to one partial inspection frequency band indicates a leak or not; and

overall determination unit that performs an overall determination process of sequentially selecting one of the plurality of partial inspection frequency bands and sequentially making the partial determination unit operate in correspondence with the selected partial inspection frequency band until the partial determination unit determines that the predetermined number or more of the inspection signals do not indicate a leak.

3. The leak inspection device according to claim 2, wherein the overall determination unit supplies the partial inspection frequency bands to the partial determination unit in ascending order of frequencies included in the partial inspection frequency bands.

4. The leak inspection device according to claim 2, wherein the overall determination unit repetitively performs the overall determination process predetermined number of times at predetermined cycles and, when all of inspection results of the overall determination process indicate presence of a leak, determines presence of a leak as an inspection result of the overall determination unit.

5. The leak inspection device according to claim 4, wherein the overall determination unit repeats the overall determination process while shortening the predetermined cycle.

6. The leak inspection device according to claim 1, wherein the inspection signal extraction unit acquires from the signal acquisition unit a signal of time which is shorter the higher a frequency included in the partial inspection frequency band as an extraction target is.

7. The leak inspection device according to claim 1, wherein the signal acquisition unit includes analog signal acquisition unit for acquiring an analog signal and digital conversion unit for converting the analog signal acquired from the analog signal acquisition unit to a digital signal, and

the digital conversion unit acquires the partial inspection frequency band from the inspection signal extraction unit and converts the analog signal to the digital signal at a sampling frequency which is higher the higher a frequency included in the partial inspection frequency band acquired is.

8. The leak inspection device according to claim 1, further comprising inspection result transmission unit that transmits an inspection result of the determination unit by radio.

9. The leak inspection device according to claim 1, further comprising power supply unit, when the determination unit determines the presence/absence of a leak as an inspection result, that stops power supply to one or more of the units.

10. The leak inspection device according to claim 9, wherein when the signal acquisition unit finishes a process, the power supply unit stops power supply to the signal acquisition unit.

11. The leak inspection device according to claim 9, further comprising inspection result transmission unit for transmitting the inspection result determined by the determination unit by radio, wherein

when the inspection result transmission unit finishes transmission of an inspection result, the power supply unit stops power supply to the inspection result transmission unit.

12. A non-transitory computer-readable storage medium storing a program causing a computer to have a function of operating as a leak inspection device, and causing the computer to have:

a signal acquisition function of acquiring a signal;

an inspection signal extraction function of extracting, as an inspection signal, a signal in any of a plurality of partial inspection frequency bands obtained by dividing a frequency band as an inspection target from the signal acquired by the signal acquisition function; and

a determination function of sequentially determining whether the inspection signals corresponding to the partial inspection frequency bands which are different from one another indicate a leak or not and, when predetermined number or more of the inspection signals do not indicate a leak, determining that there is no leak.

13. A control method executed by a computer operating as a leak inspection device, comprising:

acquiring a signal;

extracting, as an inspection signal, a signal in any of a plurality of partial inspection frequency bands obtained by dividing a frequency band as an inspection target, from the signal acquired in the signal acquisition; and

determining sequentially whether the inspection signals corresponding to the partial inspection frequency bands which are different from one another indicate a leak or not and, when predetermined number or more of the inspection signals do not indicate a leak, determining that there is no leak.