JP7286282B2 - Leak inspection system, program - Google Patents

Description

The present invention relates to a leak inspection system and its program for inspecting leaks in containers to be inspected.

When inspecting a container for leakage, gas such as air is pressurized and introduced into a container to be inspected and a reference container with no leakage, and then these are sealed. A common method is to determine whether or not there is a leak in the container to be inspected by observing the change in the differential pressure between . The basic idea is that if there is a leak in the container to be inspected, there will be a differential pressure, the magnitude of which is proportional to time.

However, the observed changes in differential pressure include changes in differential pressure due to temperature fluctuations in addition to leaks. In other words, even if the gas temperature in the inspection object container and the gas temperature in the reference container are different for some reason, a differential pressure is generated. Therefore, various techniques have been proposed to remove the effects of differential pressure caused by temperature from changes in differential pressure measured in leak inspections.

For example, in Patent Document 1 below, a workpiece, which is a container to be inspected, and a master, which is a leak-free reference container, are pressurized to the same high pressure and then left in a sealed state to measure changes in differential pressure for a predetermined period of time. perform a leak test. Furthermore, before and after this leakage inspection, a temperature compensating measuring step is performed for a predetermined period of time to measure the change in differential pressure between the work and the master when the work and the master are left sealed after being exposed to the atmosphere. Then, using the average value of the temperature compensation values (rate of change in differential pressure) obtained in the previous and subsequent temperature compensation measurement processes, the amount of change in differential pressure based on the temperature fluctuation at the time of leak inspection is estimated, and the leak inspection is performed. Temperature compensate the measurement results.

Further, in Patent Document 1, a first time period from when the temperature compensating measuring process before the leak inspection is performed to the time when the leak inspection is performed and a second time period until the temperature compensating measuring process after the leak inspection is performed are performed. Considering the case where there is a difference between the two hours, the temperature compensation value obtained in the temperature compensation measurement process before the leak test and the temperature compensation value obtained in the temperature compensation measurement process after the leak test are It is disclosed that the measurement result during the leak test is temperature-compensated with a weighted average value obtained by the inverse ratio of and the second time.

Patent No. 4994494

In Patent Document 1, temperature compensation is performed on the assumption that temperature compensation values obtained by temperature compensation measurements before and after a leak test change linearly. However, since the effect of temperature does not change linearly in practice, accurate temperature compensation is not achieved. Therefore, when the differential pressure change rate is finally detected, it is impossible to distinguish whether it is due to temperature noise that cannot be removed or due to leakage. Furthermore, it has not been possible to determine an appropriate measurement period to minimize the measurement period.

An object of the present invention is to solve the above-mentioned problems, and to provide a leak inspection system and program capable of reducing the measurement period and eliminating the influence of temperature to determine leaks with high accuracy. It is an object.

The gist of the present invention for achieving this object lies in the following inventions.

の演算で前記検査対象容器の漏れの程度を示す値としてＬを求める、もしくは前記演算で求めたＬの値と所定の許容値との比較から前記検査対象容器の漏れの有無を判断する漏れ判断ステップと、
を行うと共に、
前記リーク検査装置は、
漏れのない基準容器と、周囲と異なる温度であって漏れの無い検査対象容器とを、大気圧Ｐ_Ｅ開放から双方を封止した後、両容器の内圧の差圧の測定を一定時間行っては両容器を再び大気圧Ｐ_Ｅ開放とする工程を複数回連続的に繰り返す準備測定ステップを行って、該準備測定ステップで取得した測定データを前記情報処理装置へ出力し、
前記情報処理装置は、
前記リーク検査装置から取得した測定データ、もしくは前記測定データのうちの初めの所定回数分を除く測定データに基づいて、前記検査対象容器と前記基準容器とを大気圧Ｐ_Ｅ開放から封止した後の両容器の内圧の差圧の変化の時定数である大時定数を導出し、
前記リーク検査装置は、
前記情報処理装置が求めた前記大時定数を入力し、前記判断ステップでは、前記入力した大時定数を用いて前記Ｌの値を演算する
ことを特徴とするリーク検査システム。 [1] A leak inspection system having a leak inspection device and an information processing device,
The leak inspection device is
Repeatedly measure the differential pressure between the container to be inspected and the leak-free reference container after both are sealed from the atmospheric pressure _PE release for a predetermined period, and correspond each measured differential pressure with the measurement time. perform an atmospheric pressure sealing measurement step that is recorded with
After the end of the atmospheric pressure sealing measurement step, gas is introduced into the inspection object container and the reference container, and after pressurizing them to a predetermined test pressure _PT , both are sealed, and after sealing, Repeatedly measuring the differential pressure between the internal pressures of both containers over a predetermined period of time, performing a test pressure sealing measurement step of correlating and recording each measured differential pressure and the measurement time,
From the data recorded in the atmospheric pressure sealing measurement step, the measurement time T in the atmospheric pressure sealing measurement step of the differential pressure data when the rate of change of the differential pressure over time becomes less than a certain value a first gradient acquisition step of obtaining _a and the rate of change Q of the differential pressure at that time;
From the data measured in the test pressure seal measurement step, the measurement time T of the differential pressure data in the test pressure seal measurement step when the change rate of the differential pressure with the passage of time becomes less than a certain value a second gradient acquisition step of obtaining _b and the rate of change R of the differential pressure at that time;
Let _TS be the time difference when measuring continuously from the measurement time _Ta to the measurement time _Tb ,

L is obtained as a value indicating the degree of leakage of the container to be inspected by the above calculation, or the presence or absence of leakage from the container to be inspected is determined by comparing the value of L obtained by the above calculation with a predetermined allowable value. a decision step;
and
The leak inspection device is
After sealing both the leak-free reference container and the leak-free test container at a temperature different from the surroundings from the release of the atmospheric pressure _PE , measure the pressure difference between the two containers for a certain period of time. performs a preparatory measurement step of continuously repeating the process of opening both containers to the atmospheric pressure _PE again a plurality of times, and outputs the measurement data obtained in the preparatory measurement step to the information processing device;
The information processing device is
After the container to be inspected and the reference container are sealed from atmospheric pressure _PE release based on the measurement data acquired from the leak inspection device or the measurement data excluding the first predetermined number of times of the measurement data Derive the large time constant, which is the time constant of the change in the pressure difference between the internal pressures of both containers,
The leak inspection device is
A leak inspection system, wherein the large time constant obtained by the information processing device is input, and in the determination step, the value of L is calculated using the input large time constant.

である。よって、これをＲから減算することで漏れＬを求めることができる。大時定数の測定は、検査対象容器の１種類毎に１回行えば良い。リーク検査装置は大時定数を求めるための差圧の測定を行ってその測定データを情報処理装置へ出力し、情報処理装置はリーク検査装置から受けた測定データに基づいて大時定数を導出して出力し、リーク検査装置は情報処理装置が導出した大時定数を入力し、これを漏れ判定の演算に使用する。 There are two time constants, a large time constant and a small time constant, which govern the temperature-based change in the pressure difference between the internal pressures of both containers after the work and the master are released from the atmospheric pressure _PE and sealed. The change in differential pressure decays to a negligible size in a short period of time. In addition, regarding the change in the differential pressure related to the large time constant, the effect of the temperature change in the container that caused the change in the differential pressure based on the temperature obtained in the atmospheric pressure sealing measurement was almost the same even in the test pressure sealing measurement. presumably continuing. Therefore, when the change rate of the slope of the differential pressure curve of the atmospheric pressure measurement becomes less than a certain value (when the change related to the small time constant is attenuated to the extent that it can be ignored), the measurement time _Ta of the differential pressure data and the time Gradient (change rate of differential pressure) Q is obtained. In addition, when the rate of change of the slope of the differential pressure curve in the test pressure sealing measurement is below a certain level (when the change related to the small time constant is attenuated to the extent that it can be ignored), the measurement time _Tb of the differential pressure data and its Calculate the rate of change R of the differential pressure when R includes the change in differential pressure due to leakage and the change in differential pressure due to temperature. The amount of change in the differential pressure due to temperature included in R corresponds to the value when the slope Q at the measurement time T _a of the atmospheric pressure sealing measurement has passed to the measurement time T _b in accordance with the large time constant. That is, when the time from the measurement time _Ta to the measurement time _Tb is Ts and the pressure ratio is considered,

is. Therefore, the leakage L can be obtained by subtracting this from R. The measurement of the large time constant may be performed once for each type of container to be inspected. The leak inspection device measures the differential pressure to obtain the large time constant and outputs the measured data to the information processing device, and the information processing device derives the large time constant based on the measurement data received from the leak inspection device. , and the leak inspection device inputs the large time constant derived by the information processing device, and uses it for calculation of leak determination.

なる差分列を求める第１勾配取得ステップと、
前記試験圧封止測定ステップで記録したデータを封止時から時間Ｔ毎のグループ（グループ番号ｍ＝１、２、…Ｍ）に分け、グループ毎の差圧の平均値を時間Ｔで除した、Ｐ_ＤＤ、ｍ （ｍ＝１、２、…Ｍ） を求め、

なる差分列を求める第２勾配取得ステップと、
測定期間Ｔ_Ｍと圧縮空気導入時間Ｔ_Ｉの和をＴ_Ｓとし、

なる数列においてｍの増加に伴ってＬ_ｍの値が一定値に収束する場合にその収束値を前記検査対象容器の漏れの程度を示す値と判断する、もしくは、Ｌ_ｍの絶対値が所定の許容値以下となるｍが存在する場合に漏れ無しと判断する漏れ判断ステップと、
を行うと共に、
前記リーク検査装置は、
漏れのない基準容器と、周囲と異なる温度であって漏れの無い検査対象容器とを、大気圧Ｐ_Ｅ開放から双方を封止した後、両容器の内圧の差圧の測定を一定時間行っては両容器を再び大気圧Ｐ_Ｅ開放とする工程を複数回連続的に繰り返す準備測定ステップを行って、該準備測定ステップで取得した測定データを前記情報処理装置へ出力し、
前記情報処理装置は、
前記リーク検査装置から取得した測定データ、もしくは前記測定データのうちの初めの所定回数分を除く測定データに基づいて、前記検査対象容器と前記基準容器とを大気圧Ｐ_Ｅ開放から封止した後の両容器の内圧の差圧の変化の時定数である大時定数を導出し、
前記α_２は、

であり、
前記リーク検査装置は、
前記情報処理装置が求めた前記大時定数を入力し、該入力した大時定数に基づいて前記α_２を求め、
前記判断ステップでは、前記入力した大時定数および前記α_２を用いて前記Ｌ_ｍの値を演算する
ことを特徴とするリーク検査システム。 [2] A leak inspection system having a leak inspection device and an information processing device,
The leak inspection device is
After the container to be inspected and the reference container without leakage are sealed from the atmospheric pressure _PE release, the differential pressure between the internal pressures of both containers is repeatedly measured over the measurement period _TM , and each measured differential pressure is measured from the start of measurement. perform an atmospheric pressure sealing measurement step that is recorded together with the order of
After the end of the atmospheric pressure sealing measurement step, gas is introduced into the inspection object container and the reference container to pressurize to a predetermined test pressure _PT , and then, in the atmospheric pressure sealing measurement step After the compressed air introduction time _{TI has elapsed from the end of the measurement period TM ,} both are in a sealed state, and the differential pressure between the internal pressures of both containers after sealing is repeatedly measured over the measurement period _TM . performing a test pressure sealing measurement step of recording the pressure along with the order from the start of the measurement;
The data recorded in the atmospheric pressure sealing measurement step is divided into groups for each time T from the time of sealing (group number m = 1, 2, ... M), and the average value of the differential pressure for each group is divided by the time T , P _{ED, m} (m=1, 2, . . . M),

a first gradient obtaining step for obtaining a difference sequence of
The data recorded in the test pressure sealing measurement step is divided into groups for each time T from the time of sealing (group number m = 1, 2, ... M), and the average value of the differential pressure for each group is divided by the time T , P _{DD, m} (m=1, 2, . . . M),

a second gradient obtaining step for obtaining a difference sequence of
Let _TS be the sum of the measurement period _TM and the compressed air introduction time _TI ,

When the value of _Lm converges to a constant value as _m increases in the numerical sequence of a leakage judgment step of judging that there is no leakage when there is m that is equal to or less than the allowable value;
and
The leak inspection device is
After sealing both the leak-free reference container and the leak-free test container at a temperature different from the surroundings from the release of the atmospheric pressure _PE , measure the pressure difference between the two containers for a certain period of time. performs a preparatory measurement step of continuously repeating the process of opening both containers to the atmospheric pressure _PE again a plurality of times, and outputs the measurement data obtained in the preparatory measurement step to the information processing device;
The information processing device is
After the container to be inspected and the reference container are sealed from atmospheric pressure _PE release based on the measurement data acquired from the leak inspection device or the measurement data excluding the first predetermined number of times of the measurement data Derive the large time constant, which is the time constant of the change in the pressure difference between the internal pressures of both containers,
The α2 _is

and
The leak inspection device is
inputting the large time constant obtained by the information processing device, obtaining the _α2 based on the input large time constant,
The leak inspection system, wherein in the determination step, the value of _Lm is calculated using the input large time constant and _α2 .

In the above invention, leakage is determined by a simple calculation from the measured value of the differential pressure. That is, Q _m is a value corresponding to the slope of the differential pressure curve after time T×m from the start of atmospheric pressure seal measurement, and R _m is a value corresponding to time T×m after the start of test pressure seal measurement. It is a value corresponding to the slope of the differential pressure curve, and L _m represents the leakage after time T×m from the start of the test pressure sealing measurement. Averaging every time T removes measurement noise. When m is increased and _Lm converges to a constant value, it indicates that a transient change such as a change related to a small time constant has subsided, and the convergence value at this time indicates leakage (the convergence value is 0 no leaks).

なる数列を作成し、Ｄ_ｍが０に収束するときは、漏れがあると判断する
ことを特徴とする［２］に記載のリーク検査システム。 [3] The leak inspection device
In the leak determination step, if the absolute value of L _M-1 exceeds the allowable value,

and determining that there is a leak when _Dm converges to zero.

なる数列を作成し、Ｄ_ｍが０に収束するか否かによりその区別をつける。０に収束しなければ測定期間Ｔ_Ｍの不足であり、０に収束すればＬ_Ｍ－１で漏れを正しく判断できる。すなわち、漏れがある。 In the above invention, when the absolute value of L _M-1 exceeds the allowable value in leak judgment, it is impossible to distinguish whether there is a leak in the container to be inspected or whether the measurement time T _M is insufficient.

and make a distinction depending on whether _Dm converges to 0 or not. If it does not converge to 0, it means that the measurement period T _M is insufficient, and if it converges to 0, L _M−1 can correctly determine leakage. That is, there is leakage.

[4] The leak inspection system according to [3], wherein when _Dm does not converge to 0, the measurement period _TM is extended, and the measurement is repeated from the atmospheric pressure sealed measurement step.

[5] The leak inspection system according to any one of [2] to [4], wherein the measurement period _TM is set based on the minimum m at which _Lm converges.

In the above invention, if _Lm converges, it is possible to correctly determine whether or not there is a leak in the container to be inspected. Therefore, the measurement period _TM determined based on the minimum m when _Lm converges is the minimum measurement period that allows correct determination.

として、

の絶対値が所定の許容値以下になる最小のｍの値ｍ_ａを求める第１勾配取得ステップと、
前記試験圧封止測定ステップで記録したデータを封止時から時間Ｔ毎のグループ（グループ番号ｍ＝１、２、…Ｍ）に分け、グループ毎の差圧の平均値を時間Ｔで除した、Ｐ_ＤＤ、ｍ （ｍ＝１、２、…Ｍ） を求め、

として、

の絶対値が所定の許容値以下になる最小のｍの値ｍ_ｂを求め、ｍ_ａとｍ_ｂのうちの小さくない方の値をｋとして、Ｑ_ｋとＲ_ｋを求める第２勾配取得ステップと、
測定期間Ｔ_Ｍと圧縮空気導入時間Ｔ_Ｉの和をＴ_Ｓとし、

の演算で前記検査対象容器の漏れの程度を示す値としてＬを求める、もしくは前記演算で求めたＬの値と所定の許容値との比較から前記検査対象容器の漏れの有無を判断する漏れ判断ステップと、
を行うと共に、
前記リーク検査装置は、
漏れのない基準容器と、周囲と異なる温度であって漏れの無い検査対象容器とを、大気圧Ｐ_Ｅ開放から双方を封止した後、両容器の内圧の差圧の測定を一定時間行っては両容器を再び大気圧Ｐ_Ｅ開放とする工程を複数回連続的に繰り返す準備測定ステップを行って、該準備測定ステップで取得した測定データを前記情報処理装置へ出力し、
前記情報処理装置は、
前記リーク検査装置から取得した測定データ、もしくは前記測定データのうちの初めの所定回数分を除く測定データに基づいて、前記検査対象容器と前記基準容器とを大気圧Ｐ_Ｅ開放から封止した後の両容器の内圧の差圧の変化の時定数である大時定数を導出し、
前記α_２は、

であり、
前記リーク検査装置は、
前記情報処理装置が求めた前記大時定数を入力し、該入力した大時定数に基づいて前記α_２を求め、
前記判断ステップでは、前記入力した大時定数および前記α_２を用いて前記Ｌの値を演算する
ことを特徴とするリーク検査システム。 [6] A leak inspection system having a leak inspection device and an information processing device,
The leak inspection device is
After the container to be inspected and the reference container without leakage are sealed from the atmospheric pressure _PE release, the differential pressure between the internal pressures of both containers is repeatedly measured over the measurement period _TM , and each measured differential pressure is measured from the start of measurement. perform an atmospheric pressure sealing measurement step that is recorded together with the order of
After the end of the atmospheric pressure sealing measurement step, gas is introduced into the inspection object container and the reference container to pressurize to a predetermined test pressure _PT , and then, in the atmospheric pressure sealing measurement step After the end of the measurement period _TM and the passage of the compressed air introduction time _TI , both are in a sealed state, and the differential pressure between the internal pressures of both containers after sealing is repeatedly measured over a predetermined period, and each measured differential pressure is recorded along with the order from the start of measurement, performing a test pressure sealing measurement step,
The data recorded in the atmospheric pressure sealing measurement step is divided into groups for each time T from the time of sealing (group number k = 1, 2, ... M), and the average value of the differential pressure for each group is divided by the time T , P _{ED, m} (m=1, 2, . . . M),

As

a first gradient acquisition step of determining the minimum value of _m for which the absolute value of is less than or equal to a predetermined allowable value;
The data recorded in the test pressure sealing measurement step is divided into groups for each time T from the time of sealing (group number m = 1, 2, ... M), and the average value of the differential pressure for each group is divided by the time T , P _{DD, m} (m=1, 2, . . . M),

As

A second gradient obtaining step of obtaining the minimum m value m _b for which the absolute value of is equal to or less than a predetermined allowable value, and obtaining Q _k and R _k , where k is the larger value of m _a and m _b and,
Let _TS be the sum of the measurement period _TM and the compressed air introduction time _TI ,

L is obtained as a value indicating the degree of leakage of the container to be inspected by the above calculation, or the presence or absence of leakage from the container to be inspected is determined by comparing the value of L obtained by the above calculation with a predetermined allowable value. a decision step;
and
The leak inspection device is
After sealing both the leak-free reference container and the leak-free test container at a temperature different from the surroundings from the release of the atmospheric pressure _PE , measure the pressure difference between the two containers for a certain period of time. performs a preparatory measurement step of continuously repeating the process of opening both containers to the atmospheric pressure _PE again a plurality of times, and outputs the measurement data obtained in the preparatory measurement step to the information processing device;
The information processing device is
After the container to be inspected and the reference container are sealed from atmospheric pressure _PE release based on the measurement data acquired from the leak inspection device or the measurement data excluding the first predetermined number of times of the measurement data Derive the large time constant, which is the time constant of the change in the pressure difference between the internal pressures of both containers,
The α2 _is

and
The leak inspection device is
inputting the large time constant obtained by the information processing device, obtaining the _α2 based on the input large time constant,
The leak inspection system, wherein in the determination step, the value of L is calculated using the input large time constant and _α2 .

In the invention according to the above [2], the differential sequence L _m was created, but in the invention according to [6], the change related to the small time constant is converged (below the allowable value) at the stages of Q _{m and} R _m , Compute L using converged Q _k and R _k . It is the same as [2] except for the point of convergence at which stage.

[7] If _either ma or _mb cannot be determined, extend the measurement period _TM , and if k can be determined, set the subsequent measurement period _TM based on the value of k. The leak inspection system according to [6], characterized by:

In the above invention, when either m _a or m _b cannot be obtained, that is, when either Q _M-1 or R _M-1 does not fall below the allowable value (does not converge), the measurement period T _M is By extension, if k is obtained (both Q and R converge), the measurement period _TM is set based on that k.

を求める第１勾配取得ステップと、
前記試験圧封止測定ステップで記録したデータを封止時から時間Ｔ毎のグループ（グループ番号ｍ＝１、２、…Ｍ）に分け、グループ毎の差圧の平均値を時間Ｔで除した値を、Ｐ_ＤＤ、ｍ （ｍ＝１、２、…Ｍ）として、

を求める第２勾配取得ステップと、
測定期間Ｔ_Ｍと圧縮空気導入時間Ｔ_Ｉの和をＴ_Ｓとし、

の演算で前記検査対象容器の漏れの程度を示す値としてＬを求める、もしくは前記演算で求めたＬの値と所定の許容値との比較から前記検査対象容器の漏れの有無を判断する漏れ判断ステップと、
を行うと共に、
前記リーク検査装置は、
漏れのない基準容器と、周囲と異なる温度であって漏れの無い検査対象容器とを、大気圧Ｐ_Ｅ開放から双方を封止した後、両容器の内圧の差圧の測定を一定時間行っては両容器を再び大気圧Ｐ_Ｅ開放とする工程を複数回連続的に繰り返す準備測定ステップを行って、該準備測定ステップで取得した測定データを前記情報処理装置へ出力し、
前記情報処理装置は、
前記リーク検査装置から取得した測定データ、もしくは前記測定データのうちの初めの所定回数分を除く測定データに基づいて、前記検査対象容器と前記基準容器とを大気圧Ｐ_Ｅ開放から封止した後の両容器の内圧の差圧の変化の時定数である大時定数を導出し、
前記α_２は、

であり、
前記リーク検査装置は、
前記情報処理装置が求めた前記大時定数を入力し、該入力した大時定数に基づいて前記α_２を求め、
前記判断ステップでは、前記入力した大時定数および前記α_２を用いて前記Ｌの値を演算する
ことを特徴とするリーク検査システム。 [8] A leak inspection system having a leak inspection device and an information processing device,
The leak inspection device is
After the container to be inspected and the reference container without leakage are sealed from the atmospheric pressure _PE release, the differential pressure between the internal pressures of both containers is repeatedly measured over the measurement period _TM , and each measured differential pressure is measured from the start of measurement. perform an atmospheric pressure sealing measurement step that is recorded together with the order of
After the end of the atmospheric pressure sealing measurement step, gas is introduced into the inspection object container and the reference container to pressurize to a predetermined test pressure _PT , and then, in the atmospheric pressure sealing measurement step After the end of the measurement period _TM and the passage of the compressed air introduction time _TI , both are in a sealed state, and the differential pressure between the internal pressures of both containers after sealing is repeatedly measured over a predetermined period, and each measured differential pressure is recorded along with the order from the start of measurement, performing a test pressure sealing measurement step,
The data recorded in the atmospheric pressure sealing measurement step is divided into groups for each time T from the time of sealing (group number k = 1, 2, ... M), and the average value of the differential pressure for each group is divided by the time T Let the values be P _ED,m (m=1, 2, . . . M),

a first gradient acquisition step of determining
The data recorded in the test pressure sealing measurement step is divided into groups for each time T from the time of sealing (group number m = 1, 2, ... M), and the average value of the differential pressure for each group is divided by the time T Let the values be P _DD,m (m=1, 2, . . . M),

a second gradient acquisition step of determining
Let _TS be the sum of the measurement period _TM and the compressed air introduction time _TI ,

L is obtained as a value indicating the degree of leakage of the container to be inspected by the above calculation, or the presence or absence of leakage from the container to be inspected is determined by comparing the value of L obtained by the above calculation with a predetermined allowable value. a decision step;
and
The leak inspection device is
After sealing both the leak-free reference container and the leak-free test container at a temperature different from the surroundings from the release of the atmospheric pressure _PE , measure the pressure difference between the two containers for a certain period of time. performs a preparatory measurement step of continuously repeating the process of opening both containers to the atmospheric pressure _PE again a plurality of times, and outputs the measurement data obtained in the preparatory measurement step to the information processing device;
The information processing device is
After the container to be inspected and the reference container are sealed from atmospheric pressure _PE release based on the measurement data acquired from the leak inspection device or the measurement data excluding the first predetermined number of times of the measurement data Derive the large time constant, which is the time constant of the change in the pressure difference between the internal pressures of both containers,
The α2 _is

and
The leak inspection device is
inputting the large time constant obtained by the information processing device, obtaining the _α2 based on the input large time constant,
The leak inspection system, wherein in the determination step, the value of L is calculated using the input large time constant and _α2 .

The above invention shows the measurement method after the appropriate measurement period _TM is determined. The slopes Q _M-1 and R _M-1 of the differential pressure curve at the end of the measurement period T _M are obtained, and L is calculated from these.

[9] Sending and receiving information between the leak test device and the information processing device is performed by using one or more means of communication, recording media, and manual input operation [1] The leak inspection system according to any one of [8].

[10] Any one of [1] to [9], wherein the leak inspection device includes an operation panel, and the operation panel receives an input operation of the large time constant derived by the information processing device. 1. A leak test system as described in 1.

[11] The measurement period in the atmospheric pressure sealing measurement step is TM, and both the inspection object container and the reference container are tested in the test pressure sealing measurement step from the end of the measurement period in the atmospheric pressure sealing step. Let TI be the compressed air introduction time, which is the time it takes to pressurize to a sealed state,
The information processing device, instead of the large time constant,
β = exp (-(TM + TI) / large time constant)
and derive
The leak inspection system according to any one of [1] to [10], wherein the leak inspection device inputs the β derived by the information processing device and uses it for calculation.

[12] A program executed by an information processing device in the leak inspection system according to any one of [1] to [10],
inputting the measurement data from the leak test device;
Based on the measurement data, one of the two time constants governing the temperature-based change in the pressure difference between the internal pressures of the container to be inspected and the reference container after the containers are sealed from the atmospheric pressure _PE deriving the larger time constant, the large time constant;
an output step of outputting the derived large time constant;
A program with

[13] A program executed by an information processing device in the leak inspection system according to [11],
inputting the measurement data from the leak test device;
Based on the measurement data, one of the two time constants governing the temperature-based change in the pressure difference between the internal pressures of the container to be inspected and the reference container after the containers are sealed from the atmospheric pressure _PE obtaining the large time constant, which is the larger time constant, to derive the β;
an output step of outputting the derived β;
A program with

According to the leak inspection system and program according to the present invention, it is possible to eliminate the effect of temperature and determine leaks with high accuracy while reducing the measurement period.

1 is a diagram showing a system configuration of a leak inspection system according to an embodiment of the invention; FIG. 1 is a diagram showing a schematic configuration of a leak inspection device included in a leak inspection system according to an embodiment of the present invention; FIG. 4 is a graph showing, on a continuous time axis, a differential pressure curve based on measurement data obtained in an atmospheric pressure sealing measurement process and a differential pressure curve based on measurement data obtained in a test pressure sealing measurement process; FIG. 10 is a diagram showing a change in temperature difference between the work and the gas in the master from the atmospheric pressure sealing measurement process to the test pressure sealing measurement process; 4 is a flow chart showing processing performed by the leak inspection system 5 in a large time constant derivation step; FIG. 4 is a diagram showing a differential pressure measurement sequence in a preparatory measurement process; It is a figure which shows the relationship between average gradient _G0 , _G1 , _G2 ,... in the differential pressure measurement of each time measured by the preparation measurement process, and the start time of each time. It is a figure which shows an example of the measurement data which a leak test apparatus transmits to an information processing apparatus. 9 is a diagram showing intermediate data derived by the information processing device based on the data of FIG. 8; FIG. FIG. 10 is a diagram showing a least-squares straight line obtained based on the plotted points of the intermediate data in FIG. 9; 4 is a flow chart showing processing performed by the leak inspection system in a general leak inspection process;

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below based on the drawings.

FIG. 1 shows a schematic configuration of a leak inspection system 5 according to the present invention. The leak inspection system 5 is a device for inspecting leaks in a container to be inspected (for example, a heat exchanger or a hot water tank of a water heater). and a leak inspection device 10 that introduces gas into the master 3 that has been confirmed to be leak-free and measures the differential pressure therebetween, and an information processing device 60 that performs data processing. be done. Workpiece 2 and master 3 are different containers with the same mechanical and thermodynamic parameters. The leak test device 10 and the information processing device 60 are communicably connected to exchange data.

As shown in FIG. 2, the leak test device 10 includes a pressurization source connection port 11, a work connection port 12, a master connection port 13, and an exhaust port 14. has a first pipe 21 with one end connected to the pressurized source connection port 11, the first pipe 21 branches into two on the way to become a second pipe 22 and a third pipe 23, and the second pipe 22 The other end is connected to the work connection port 12, and the other end of the third pipe 23 is connected to the master connection port 13, respectively.

A first on-off valve 31 is inserted in the first pipe 21 . A second on-off valve 32 is inserted in the second pipe 22 . A third on-off valve 33 is inserted in the third pipe 23 . The second pipe 22 between the second on-off valve 32 and the work connection port 12 is branched on the way and connected to one connection port of the differential pressure gauge 37 . Similarly, the third pipe 23 between the third on-off valve 33 and the master connection port 13 is branched and connected to the other connection port of the differential pressure gauge 37 . The differential pressure gauge 37 measures the difference (differential pressure) between the pressure applied to one connection port and the pressure applied to the other connection port. A fourth pipeline 24 branches off from the third pipeline 23 at a predetermined location between the first on-off valve 31 and the third on-off valve 33, and the fourth on-off valve 34 is provided in the middle of the fourth pipeline 24. There is. The end of the fourth pipeline 24 is an exhaust port 14, and the exhaust port 14 is open to the atmosphere.

The leak test device 10 controls the opening and closing of the valve and the test flow, measures the differential pressure, records the measurement results, performs calculations for leak determination based on the recorded measurement results, and exchanges data with the information processing device 60. and the like. The inspection processing unit 40 includes a control unit 41 including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), etc., and a storage unit 42 connected to the control unit 41 through a bus. It is composed of an operation panel 43 , a valve control I/F 46 , a differential pressure gauge I/F 47 , a communication section 48 and a recording medium I/F 49 .

The CPU of the control unit 41 executes various processes in accordance with programs stored in the ROM, thereby performing inspection operations, calculations, determinations, and the like in the leak inspection apparatus 10 .

The storage unit 42 is composed of a RAM, a non-volatile memory, a hard disk device, etc., and stores set inspection conditions, measured data, and the like. The operation panel 43 has an operation input section 44 for receiving various setting operations from the user, and a display section 45 for displaying various operation screens, setting screens, screens showing operation status, and the like to the user. The display unit 45 is composed of a liquid crystal display or the like. The operation input unit 44 is composed of software switches by a touch screen provided on the display screen of the display unit 45 and other mechanical switches. The leak test apparatus 10 receives input operations of various set values from the user through the operation panel 43 .

The valve control I/F 46 outputs a control signal (a signal instructing opening/closing) to each of the first opening/closing valve 31 to the fourth opening/closing valve 34 . The differential pressure gauge I/F 47 functions to output a control signal to the differential pressure gauge 37 and input a detection signal output by the differential pressure gauge 37 . The communication unit 48 functions to exchange various data with the information processing device 60 and other external devices. Any communication method may be used, for example, LAN (Local Area Network), serial communication by RS-232C, USB, or the like. A recording medium I/F 49 reads/writes data from/to a storage medium such as a memory card, USB memory, or CD.

A pressure source, which is a supply source of pressurized gas, is connected to the pressurization source connection port 11 via an electropneumatic regulator (not shown) or the like.

A work 2 is connected to the work connection port 12 and a master 3 is connected to the master connection port 13 .

As shown in FIG. 1, the information processing device 60 is configured by connecting a storage unit 62, a communication unit 63, a user I/F 64, and a recording medium I/F 67 to a CPU 61 via a bus. The storage unit 62 is composed of a ROM, a RAM, a nonvolatile memory, a hard disk device, and the like. The communication unit 63 functions to exchange various data with the leak test device 10 and other external devices. Any communication method may be used as in the case of the communication unit 48 of the leak test apparatus 10 . The user I/F 64 is connected to an operation input unit 65 such as a keyboard, mouse, and touch screen for receiving user operations, and a display unit 66 such as a liquid crystal display for displaying various screens. The display unit 66 displays calculation results, leakage determination results, and the like. A recording medium I/F 67 reads/writes data from/to a storage medium such as a memory card, USB memory, or CD.

The information processing device 60 performs data transmission and reception of the leak test device 10 and data processing according to the present invention by the CPU 61 performing processing according to a program stored in the storage unit 62 . The information processing device 60 may be configured by installing software for performing data processing and the like according to the present invention on a general-purpose personal computer (PC).

Next, the outline of the present invention will be explained.

In the leak inspection by the leak inspection system 5 according to the present invention, the workpiece 2 and the master 3 are released from the atmospheric pressure _PE , and then sealed. Measurement is performed repeatedly over a period of time, and an atmospheric pressure sealing measurement step is performed in which each measured differential pressure is associated with a measurement time (in place of the measurement time, the measurement order may be used if the measurement time can be specified) and recorded. Next, after the end of the atmospheric pressure sealing measurement process, gas is introduced into the workpiece 2 and the master 3, and after pressurizing them to a predetermined test pressure _PT , both are sealed, and both containers after sealing are sealed. Repeatedly measure the differential pressure of the internal pressure over a predetermined period, and record each measured differential pressure in association with the measurement time (in place of the measurement time, the measurement order can be used if the measurement time can be specified). carry out the process.

Then, from the data recorded in the atmospheric pressure sealing measurement process, the difference (rate of change) in the gradient (rate of change in differential pressure) of the graph (differential pressure curve) showing the change in differential pressure over time is below a certain level. A first gradient acquisition step for obtaining the measurement time _Ta in the atmospheric pressure sealing measurement step of the differential pressure data when it becomes and the rate of change (gradient) Q of the differential pressure at that time, and test pressure sealing measurement From the data recorded in the process, test the differential pressure data when the difference (change rate) of the differential pressure gradient (change rate of differential pressure) with the passage of time becomes below a certain level. A second gradient obtaining step is performed to obtain the measurement time _Tb and the rate of change (gradient) R of the differential pressure at that time.

の演算で求める、もしくはＬの値に基づいてワーク２の漏れの有無を判断する漏れ判断工程を行う。 After that, the time difference in the case where the measurement time T _a to the measurement time T _b is continuously measured is T _S , and the leakage L of the workpiece 2 is

or based on the value of L.

FIG. 3 shows the change in differential pressure over time based on the measurement data obtained in the atmospheric pressure sealing measurement process and the differential pressure change over time based on the measurement data obtained in the test pressure sealing measurement process. 4 is a graph (differential pressure curve) represented on a continuous time axis from the start of the measurement process. The differential pressure change in the test pressure sealing measurement process is the sum of the differential pressure change due to leakage from the workpiece 2 and the differential pressure change based on the temperature. On the other hand, the differential pressure change in the atmospheric pressure sealed measurement process is considered to be only the differential pressure change based on the temperature.

However, the atmospheric pressure seal measurement process and the test pressure seal measurement process cannot be performed simultaneously on the same workpiece 2 . Therefore, in the present invention, from the slope Q (change rate of differential pressure) of the differential pressure curve obtained in the atmospheric pressure sealing measurement step performed immediately before the test pressure sealing measurement step, the temperature in the test pressure sealing measurement step By subtracting the value obtained by multiplying the ratio of the test pressure and the atmospheric pressure by the ratio of the test pressure to the atmospheric pressure from the slope R of the differential pressure curve obtained in the test pressure seal measurement process, the test pressure seal measurement Estimate the rate of change in differential pressure due to leakage in the process (leakage L).

FIG. 4 shows changes in the temperature difference between the gas temperature in the workpiece 2 and the gas temperature in the master 3 on the same time axis as in FIG. The gas temperature in the workpiece 2 changes as shown by the curve AB in the atmospheric pressure sealed measurement process, and if the pressure to the test pressure is not performed after the atmospheric pressure sealed measurement process, the change will continue as it is, It comes to be shown by the dashed line BC. In reality, the gas inside the container is adiabatically compressed by being pressurized to the test pressure, and the temperature rises, so it changes like a BDE (the graph is exaggerated).

However, since the heat capacity of the container is sufficiently large compared to air, and the heat generated by pressurization is almost the same for both the work 2 and the master 3, for example, even if the air in the container is adiabatically compressed to 1/6, , the difference in the gas temperature inside the workpiece 2 and the master 3 is almost the same as when no pressure is applied. That is, in reality, it becomes a curve that almost overlaps with ABC like ABD'C in FIG.

Since absolute temperature and pressure are proportional, the change in differential pressure due to temperature at the test pressure is similar to the change in temperature difference. That is, it is presumed that the change in the differential pressure due to the temperature in the atmospheric pressure sealing measurement process continues as it is in the subsequent test pressure sealing measurement by multiplying the sealing pressure ratio.

の演算で漏れＬを求めて、漏れの有無を判断する。なお、上記温度による差圧の変化を支配する２つの時定数の内の小さい方を小時定数とする。 Therefore, among the two time constants that govern the change in the pressure difference between the internal pressures of the two containers after the work 2 and the master 3, which have a temperature difference, are sealed from the release of the atmospheric pressure _PE (this is a change based on temperature), A large time constant, which is the larger time constant of , is obtained by measuring in advance. Then, in the leak determination step, the gradient Q is corrected by the elapsed time TS from the measurement time _Ta of the gradient Q to the measurement time _Tb of the gradient R and the large time constant, and the gradient R is measured at _{time Tb} . Estimate the rate of change of differential pressure with temperature when Also, the difference between the atmospheric pressure and the test pressure is corrected by P _T /P _E . i.e.

The leakage L is obtained by the calculation of , and the presence or absence of leakage is determined. The smaller one of the two time constants governing the change in differential pressure due to temperature is defined as the small time constant.

In the first gradient acquisition process and the second gradient acquisition process, by acquiring the gradient (differential pressure change rate) after the gradient change rate of the differential pressure curve falls below a certain level, It waits until the differential pressure change or the like related to the constant is sufficiently attenuated to the extent that it can be ignored.

Next, a more detailed theoretical explanation of the invention will be given.

Here, we deal with the case where the ambient temperature change within the measurement time can be ignored. If the ambient temperature changes appreciably within the measurement time, another method should be considered. It occurs when the measurement time is long, or when ventilation is performed quickly. TECHNICAL FIELD The present invention relates to a leak test method in which measurement is completed in such a short period of time that changes in environmental temperature of a container or the like can be ignored.

The differential pressure used below is
Differential pressure P _D = (internal pressure of master) - (internal pressure of workpiece)
and

である。ただしＰ_Ｃを封止圧力とするとき

であって、Ｇは質量流量、Ｍ_Ｃは封止された空気質量である。この質量流量Ｇは、Ｐ_Ｅを環境圧力、Ｋ_Ｖをリークを生じさせている孔により定まる定数として

である。Ｃ_１及びＣ_２は温度の初期条件で決定するので、漏れ測定前に知ることはできない。 In FIG. 2, when the time when the second on-off valve 32 and the third on-off valve 33 are closed is t=0, the differential pressure generated when the ambient temperature does not change is

is. However, when _PC is the sealing pressure

where G is the mass flow rate and M _C is the sealed air mass. This mass flow rate G is defined by P _E being the ambient pressure and K _V being the constant determined by the leaking hole.

is. Since _C1 and _C2 are determined by initial conditions of temperature, they are not known prior to leak measurement.

Parameters that can be known prior to leak measurement are:
Gas constant: R
Parameters determined by the product (time constant of temperature change): T _1, T _2,
Known quantities determined by test conditions: P _C, P _E, M _C, μ _, θ _0,
μ is the air viscosity and θ ₀ is the air temperature. _T1 is a small time constant and _T2 is a large time constant.

Equation (1) holds true both when _PC is at atmospheric pressure and at test pressure. However, the parameters are all different and the origin of time is also different.

が成り立つものである。差圧の計測、記録は、測定期間である時間Ｔ_Ｍにわたって行う。Ｔ_Ｍの大きさの目安は、

である。なお、大気圧での時間Ｔ_Ｍにわたる差圧測定と次の試験圧での差圧測定の開始の間には加圧するためにインターバルＴ_Ｉが必要である。おおむね

程度のＴを選んで

とおく。これらは、差圧の時間的な変化の比較において使用する。 A container to which the present invention can be suitably applied is

is established. The measurement and recording of the differential pressure are performed over the time _TM , which is the measurement period. A guideline for the size of _TM is

is. Note that an interval _TI is required to pressurize between the differential pressure measurement over time _TM at atmospheric pressure and the start of the differential pressure measurement at the next test pressure. Generally

Choose a degree of T

far. These are used in comparison of temporal changes in differential pressure.

である。式(9)から式(1)のα_２倍を引くと、大時定数の指数関数を消去することができる。式(10)の左辺はリークを評価するための関数である。

<Approximate the state of pressure change with one exponential function>
Now, substituting t+T for t in equation (1), we get

is. Subtracting α2 _times Eq. (1) from Eq. (9) eliminates exponential functions with large time constants. The left side of Equation (10) is a function for evaluating leaks.

であるが、式(4)、(3)、(2)により、

である。これを式(10)に代入して、次式を得る

左辺の観測値をプロットすれば、それは定数と指数関数の和となる。式(13)の左辺を測定値から求め、その変化が微小になれば、測定を打ち切る。 First, consider the first measurement at atmospheric pressure.
If a differential pressure occurs after the container is filled with ambient pressure P _E (atmospheric pressure) and sealed, it is said that the differential pressure is caused by a change in the internal gas temperature. At this time, in formula (2)

However, by formulas (4), (3), and (2),

is. Substituting this into equation (10), we obtain the following equation

Plotting the observations on the left side gives the sum of a constant and an exponential function. The left side of equation (13) is obtained from the measured value, and the measurement is stopped when the change becomes minute.

程度とすれば、式(13)の右辺第２項が微小となり、温度により生じる圧力変化率が

と、求められる。これは、時定数Ｔ_２が非常に大きいことによる、見せ掛けの質量変化率（偽りの漏れ）である。 Equation (13) indicates that even if the temperature difference between the two containers (workpiece and master) becomes zero after a sufficient amount of time has passed, the differential pressure does not become zero. The time required for measurement is the time until the value of equation (13) converges to the extent that it can be regarded as constant. therefore

If the second term on the right side of equation (13) becomes minute, the rate of pressure change caused by temperature becomes

and asked. This is a spurious mass change rate (false leakage) due to the very large time constant _T2 .

としなければならない。初期値により定まる定数が前と異なるので、ここではＣ´_１、Ｃ´_２と記号を区別してある。大気圧による第１回目の測定と試験圧による第２回目の測定との時間的な関係は図２に示される。 A second measurement is then made with the test pressure _PT sealed in both vessels. Since the pressure changes, it cannot be said that C ₀ =0. Also, since the time origin is changed, the temperature initial value is changed. Therefore, instead of equation (13)

must be Since the constants determined by the initial values are different from the previous ones, the symbols C _{' 1} and C _{' 2} are distinguished here. The temporal relationship between the first measurement with atmospheric pressure and the second measurement with test pressure is shown in FIG.

When the test pressure is applied to the container, a leak will occur if there is a leak hole. On the other hand, regardless of the presence or absence of leakage, changes in gas pressure occur within the container due to changes in temperature. The observed differential pressure change is the sum of the differential pressure change due to leakage and the differential pressure change due to temperature. These separations require some inference, since it is not possible to make simultaneous measurements with and without pressure on the same vessel. Therefore, the differential pressure change due to temperature is estimated, and if a differential pressure different from the estimated value is observed, the difference is assumed to be a pressure change due to "leakage".

これに式(13)、(16)を代入して

First, find the following quantities:

Substituting equations (13) and (16) into this,

Now, regardless of the presence or absence of measurements, heat exchange between the container and the external environment continues. However, when the container is pressurized, the gas inside is compressed and heat is generated. This causes the temperature of the air to rise, and the heat transfer to the container also raises the temperature of the container. Since the amount of heat generated by pressurization is almost the same between the master and the work, the container temperature difference is approximated by a continuous change determined by the time constant _T2 , and the container temperature difference can be estimated under that condition. FIG. 4 illustrates the change in vessel temperature difference over two measurements.

A curve AB represents the temperature difference of the air inside the container when measuring with atmospheric pressure sealing. Without pressurization, this curve continues like the dashed line BD'C. This curve is an extension of AB and is mathematically determined by the progress up to AB. Since BD' is a pressurization process, the temperature difference is similar to BD, but since D' and D often overlap, such a case is considered here. After that, the temperature follows a changing process represented by the heat dissipation of the container like DE, but it can be assumed that the curve almost overlaps with D'C. There may be instances where this assumption does not hold, and application of the present invention to such instances will lead to inaccurate results.

と近似することができて、加圧後の時刻の原点はＴ_Ｍ＋Ｔ_Ｉだけ、加圧前の大気圧封止測定よりも後である。加圧後の時間、初期値など関係量は、大気圧封止の場合の記号にダッシュ（´）をつけて表す。しからば、ＢＣとＤＥがほとんど重なっているので、

であるが、Ｔ_２＞＞Ｔ_１であるから、通常は第２項は第１項に比べて微小である。 Now, the curve ABC is

and the origin of the time after pressurization is later than the atmospheric pressure seal measurement before pressurization by T _M +T _I . Relevant quantities such as the time after pressurization and the initial value are indicated by adding a dash (') to the symbol for sealing at atmospheric pressure. Since BC and DE almost overlap,

However, since T ₂ >>T ₁ , the second term is usually smaller than the first term.

と推定できる。それゆえ、漏れによる圧力変化率は

となる。この右辺第２項が減衰するのは、データを観測して待つべき時間を調査する。これはＬの経時特性から、減衰の時定数Ｔ_１を観測すれば、毎度調べる必要はない。式(23)式の右辺の第２項が減衰した後に残る右辺の第１項は漏れを表しているから、測定値から求まる式(17)の演算結果は、漏れを示すことになる。 therefore

can be estimated. Therefore, the rate of pressure change due to leakage is

becomes. The attenuation of the second term on the right side is investigated by observing the data and waiting time. This does not need to be checked every time if the time constant _T1 of attenuation is observed from the characteristics of L over time. Since the first term on the right side of Equation (23) that remains after the second term on the right side of Equation (23) attenuates represents leakage, the calculation result of Equation (17) obtained from the measured value indicates leakage.

The right side of Equation (17) obtained from the measured values contains noise. Also, to see the leak, it is necessary to wait for the decay of the exponential term on the left side (equation (23)). Noise is approximately eliminated by averaging L over time T. Even if this averaging is performed before the above data processing, the result is the same.

Leakage estimation is performed by calculating equation (17) from the data. This calculation requires prior knowledge of the large time constant _T2 . Once the differential pressure time curve is determined without heating the master but with the work piece, the value of _T2 can be known with sufficient accuracy.

Next, a description will be given of an inspection process for measuring the differential pressure and performing calculation corresponding to equation (17) to determine the presence or absence of leakage.

The leak inspection system 5 carries out a large time constant derivation step of obtaining a large time constant by performing a predetermined measurement, and then carries out a general leak inspection step of checking the presence or absence of leakage in the workpiece 2 . The measurement of the large time constant can be performed once for one type of measurement object, and the individual leak inspection can be performed by simply executing a general inspection process. First, the large time constant derivation step will be described.

<Measurement of large time constant (T ₂ )>
FIG. 5 is a flow chart showing the processing performed by the leak inspection system 5 in the large time constant derivation process. First, the leak test apparatus 10 performs a preparatory measurement step for measuring a large time constant (step S101). In the preparatory measurement process, a leak-free master is connected to the master connection port 13 of the leak tester 10, and a work whose temperature is different from the surroundings and is confirmed to be leak-free is connected to the work connection port 12. - 特許庁

Next, the workpiece and the master are released to the ambient air, sealed, and the differential pressure measurement is started. At time t=0, the valves (second on-off valve 32, third on-off valve ₃₃ ) are shut off to start differential pressure measurement. Perform the operation to return to zero (state of differential pressure 0 when open to the atmosphere). A short _TA is selected so that a differential pressure curve obtained by differential pressure measurement over a certain time _TA can be linearly approximated.

In the preparatory measurement step, such differential pressure measurement over a certain period of time _TA is repeated a plurality of times with an open-to-air period of _TB time intervening. That is, as shown in FIG. 6, the first differential pressure measurement (E ₀ ) over a certain period of time _TA is performed after opening to the atmosphere at t = 0, opening to the atmosphere for _TB time, and sealing again. 2nd differential pressure measurement (E ₁ ) over a certain period of time TA, release to the atmosphere for _TB time _, sealing again and 3rd differential pressure measurement (E ₂ ) over a certain period of time _TA , etc. and repeat the differential pressure measurement.

For example, in one differential pressure measurement, the fixed time _TA is set to 50 seconds, and the differential pressure is measured every 0.2 seconds over 50 seconds. The time _TB is around 10 seconds, and differential pressure measurement is repeated, for example, 20 times. At this time, the actual start time of each differential pressure measurement (StartTime: elapsed time from the start time of the first differential pressure measurement (t=0), ST ₁ , ST ₂ . . . ) is measured.

The leak test apparatus 10 obtains average gradients _{G 0 , G 1} , G ₂ , . FIG _. 7 shows the relationship between the average gradients G ₀ , G ₁ , G ₂ , . The horizontal axis of FIG. 7 is time, and the vertical axis is differential pressure. The leak test apparatus 10 creates data that associates the start time (StartTime: ST _n ) of each time with the average gradient G _n of that time, and outputs the data to the information processing device 60 ( FIG. 5 , step S102). FIG. 8 shows an example of measurement data that the leak test device 10 transmits to the information processing device 60 .

Leak test apparatus 10 transmits measurement data to information processing apparatus 60 by serial communication such as RS-232C, for example.

The information processing device 60 receives measurement data from the leak test device 10 (FIG. 5, step S201), and derives a large time constant by calculation based on the received measurement data (step S202). Derivation of the large time constant is performed as follows.

となっているから、両辺の対数を取った形

から、最小二乗法で１／Ｔ_２を求めれば良い。ｋ＝３くらいまでのデータは、もう一つの時定数の影響を受けることがあるので、削除してから、残りのデータを使ってＴ_２を求めるほうが、より真値に近くなる。 The differential pressure curve in each differential pressure measurement (E ₀ to E _n ) has a short T _A so that it can be regarded as almost a straight line. At this time,

Therefore, the logarithm of both sides is taken as

Therefore, 1/ _T2 can be obtained by the method of least squares. The data up to about k=3 may be affected by another time constant, so deleting it and then using the remaining data to calculate _T2 will bring it closer to the true value.

Specifically, the information processing device 60 obtains Log( _G1 / _G0 ), Log( _G2 / _G0 ), Log( _G3 / _G0 ), . . . based on the data in FIG. The data shown in FIG. 9 are created in correspondence with the StartTime (ST _n ) of each time. 9 are plotted _on coordinates as _{shown in} FIG. Find the least-squares straight line for . Then, the reciprocal of the slope of this least-squares straight line is derived as the large time constant.

The information processing device 60 outputs the derived large time constant to the leak test device 10 (FIG. 5, step S203), and the leak test device 10 inputs the large time constant output by the information processing device 60 (step S103), the large time constant derivation step ends.

Here, the information processing device 60 displays the large time constant on the display unit 66 of its own device, the user visually reads this, and the value is input to the leak test device using the operation input unit 44 of the operation panel 43. Enter 10 manually. It should be noted that the transfer of the large time constant from the information processing device 60 to the leak test device may be performed by communication instead of manual input, or may be performed via a recording medium.

Next, a general leak inspection process for measuring leaks in the work 2 will be described.

When the time used for leak measurement is one minute to several minutes, the differential pressure is measured and recorded at each time step s of about 0.1 second. Let T be n times this time step s (where n is an integer and is approximately 10 or more), and M times T (where M is an integer and approximately 4 or more) = _TM is the differential pressure recording time (measurement period _TM ). . The time from the completion of measurement recording over _TM at atmospheric pressure sealing to the start of the next differential pressure measurement at the test pressure is _TI , and _TI is set as short as possible. If the time used for leak measurement is long, s may be increased accordingly.

である。Ｔ、Ｔ_Ｍ、Ｔ_Ｉは試験者が任意に定めることができるが便宜上、Ｍを正整数としてＴ_ＭはＴのＭ倍に設定する。大時定数Ｔ_２は試験体（ワーク）によって定まる固有値により決定するもので、試験体によって定まる。Ｔ_２は製品が決まれば決定するので、前述のようにして、一度測定しておけば、その後の同じ製品に対して、その値を使い続けることができる。 <Determination of α and β>
To determine the presence or absence of leakage by performing the calculation corresponding to equation (17), it is necessary to specify the values of α and β included in equation (17). A pressure transient response is represented by a linear function and the sum of two first-order lag step responses. This is the time constant of the first-order lag step response.

is. T, _TM , and _TI can be arbitrarily determined by the tester, but for convenience, M is a positive integer and _TM is set to M times T. The large time constant _T2 is determined by the eigenvalue determined by the specimen (work), and is determined by the specimen. Since _T2 is determined once the product is determined, once it is measured as described above, that value can be used continuously for the same product thereafter.

<General leak inspection process>
FIG. 11 shows the flow of a general leak inspection process. First, the master 3 is connected to the master connection port 13 of the leak inspection device 10 with the first on-off valve 31 closed, and the work 2 to be inspected is connected to the work connection port 12 (FIG. 11, step S121).

Next, the leak test apparatus 10 performs an atmospheric pressure sealing measurement step (step S122). In the atmospheric pressure sealed measurement process, the leak test apparatus 10 opens the second on-off valve 32, the third on-off valve 33, and the fourth on-off valve 34 to release the atmospheric pressure _PE , and then closes the fourth on-off valve 34. Furthermore, the second on-off valve 32 and the third on-off valve 33 are closed at the same time to seal the workpiece 2 and the master 3 at atmospheric pressure. With the time when both are sealed as the start point of measurement, the differential pressure between the internal pressures of both containers is repeatedly measured every time s over the measurement period _TM , and each measured differential pressure is listed together with the order from the start of measurement (for example, sequentially). As described above, n times the time s is T, and an integer multiple (M times, eg, 10 times) of T is the measurement period _TM . Instead of the order of measurement, it may be recorded in association with the time of measurement.

After the measurement under atmospheric pressure is completed, a test pressure sealing measurement step is performed (FIG. 11, step S123). Specifically, the leak test apparatus 10 opens the first on-off valve 31 after opening the second on-off valve 32 and the third on-off valve 33 to introduce gas from the pressure source into both the workpiece 2 and the master 3. Pressurize to test pressure. After pressurizing to the test pressure, the first on-off valve 31 is closed, and the second on-off valve 32 and the third on-off valve 33 are closed at the same time to seal the work 2 and the master 3 at the test pressure.

With the time when both are sealed as the start point of measurement, the differential pressure between the internal pressures of both containers is repeatedly measured every time s over the measurement period _TM , and each measured differential pressure is listed together with the order from the start of measurement (for example, sequentially). The test shall proceed so that the time (charge time) from the end of measurement with atmospheric pressure sealing to the start of measurement with test pressure sealing equals the predetermined compressed air introduction time _TI .

Differential pressure measurements are performed and recorded as a set of two measurements, an atmospheric pressure sealing measurement followed by a test pressure sealing measurement. The large time constant _T2 of the workpiece to be inspected is obtained in advance in the large time constant derivation process described above and is input to the leak inspection apparatus 10. Further, α and β are obtained in advance using equations (26) and (27). Keep In a general leak inspection process, calculations are performed using the above large time constants α and β.

In the large time constant derivation step described above, the information processing device 60 derives the large time constant and inputs it to the leak test device 10. You may make it input to the inspection apparatus 10. FIG. In this case, in step S102 of FIG. 5, the time T _{S ,} that is, the value of (T _M +T _I ) is transmitted from the leak test device 10 to the information processing device 60, and the information processing device 60 obtains this value and its own device. β is obtained from the equation (27) from the large time constant _T2 . When the value of β is calculated by the information processing device 60 instead of the large time constant _T2 and is input to the leak test device 10, the leak test device 10 calculates the value of β based on the value of β received from the information processing device 60. Derive the value of α.

Next, the leak inspection apparatus 10 performs an arithmetic judgment step for judging whether or not there is a leak in the workpiece 2 based on the differential pressure data obtained by measuring in the atmospheric pressure sealing measurement step and the test pressure sealing measurement step. 11 (step S124 in FIG. 11) to end this process. When inspecting a plurality of workpieces 2, the process of FIG. 11 may be repeated. The calculation determination process includes the above-described first gradient acquisition process, second gradient acquisition process, and leakage determination process. In the calculation determination step of S124, the calculation described below is performed.

とする。これから、ｎ個(時間Ｔ)ごとの平均値を作って記録する。この処理は測定中に行って、その結果だけを記録してもよい。

これより次の数列をつくる。

Ｑ_ｍは項数がＭ－１の数列である。 [Calculation based on differential pressure data of atmospheric pressure sealing]
The recorded differential pressure is

and From this, an average value is created and recorded every n (time T). This process may be performed during the measurement and only the results recorded.

From this we create the following sequence:

Q _m is a sequence with M−1 terms.

これより

をつくる。Ｒ_ｍは項数がＭ－１の数列である。 [Calculation based on differential pressure data of test pressure sealing]
As in the case of atmospheric pressure sealing, the differential pressure is divided into n units, and the average value is created and recorded. This process may be performed during the measurement and only the results recorded.

Than this

create. R _m is a sequence with M−1 terms.

この数列は、漏れにより発生する差圧の変化率の近似値であって、ｍの増加にともない一定値に近づく。この収束値を用いて、漏れＵは次式で表される。

漏れの許容値Ｕ_Ｃが定めてあるときには、次式が成り立つ場合を漏れ検査合格とする。

[Calculation of leak determination based on Q _m and R _m ]
From Q _m and R _m make the following sequence.

This progression is an approximation of the rate of change in differential pressure caused by a leak, and approaches a constant value as m increases. Using this convergence value, the leakage U is expressed by the following equation.

When the allowable value of leakage _UC is specified, the leakage test is passed when the following equation holds.

Equation (35) may not hold in general measurements. At that time, a leak is suspected, but there are cases where it is not a leak. Therefore, the following processing is performed when the formula (35) does not hold.

をつくり、Ｄ_ｍが０に収束するときには、得られているＬ_Ｍ－１は漏れを表している。
このとき

ならば、差分列Ｄ_ｍは０に収束していない。Ｄ_ｍが０に収束していないならば、それは、温度の過渡現象が計測時間内に落ち着いていないことを表している。この場合には、得た結果を破棄し、単に再測定を行うか、Ｍの値を増やして再計測を行い、式(36)以下の判定を再度行う。これで測定終了となる。 [Processing when leakage is suspected]
If the value of LM _-1 is large, suspect a leak. At this time, the recorded sequence {L _M } is examined. That is, the difference sequence of L _M

and when D _m converges to 0, the resulting L _M−1 represents leakage.
At this time

, then the difference sequence D _m has not converged to 0. If _Dm does not converge to 0, it indicates that the temperature transient has not settled within the measurement time. In this case, the obtained result is discarded and the measurement is simply performed again, or the value of M is increased and the measurement is performed again, and the determination following equation (36) is performed again. This completes the measurement.

If _Dm does not converge to 0 at this stage, there is a suspicion that the instrument or measurement system is inappropriate, or that parameters have been entered incorrectly.

The following cautions are necessary for this re-measurement. When the transferred work is particularly hot or cold compared to the ambient temperature, the measurement time may be insufficient. In such a case, since the temperature approaches the ambient temperature by the first measurement, _LM-1 converges to 0 even if the measurement is repeated without extending the measurement time, and the equation (35 ) may come to hold. At this time, the second measured value is correct, and the first L _M-1 is a value that did not reach convergence because the initial temperature difference was excessive.

[shortest measurement period T _M ]
If L _m converges to a constant value with m less than or equal to M−1, measure the minimum m that converges to a constant value (or the value obtained by adding a small amount of margin (eg, 1 or 2)) as the new M A period _TM may be defined. Similarly, the minimum m that satisfies equation (35) (or a value obtained by adding a small margin amount (eg, 1 or 2) to this) may be used as a new _M to determine the measurement period TM. In this way a minimum measurement period _TM can be set. Subsequent tests on the same product may use this measurement period _TM .

の絶対値が所定の許容値以下になる最小のｍの値ｍ_ａを求める。また、式(32)の数列を求めた後、

の絶対値が所定の許容値以下になる最小のｍの値ｍ_ｂを求める。次にｍ_ａとｍ_ｂのうちの小さくない方の値をｋとして、Ｑ_ｋとＲ_ｋを求める。ここでは、ｒ_ｍについては、最初にｍ＝ｍ_ａでｒ_ｍを求め、その絶対値が所定の許容値以下ならばｍ_ａをｋとする。その絶対値が所定の許容値以下でなければ、ｍの値をｍ_ａから＋１ずつ増して行き、ｒ_ｍの絶対値が所定の許容値以下になる最小のｍの値をｋとする。 <Modified example of general leak inspection process>
In the modified example, convergence is confirmed at the stages of equations (30) and (32). That is, after obtaining the sequence of equation (30),

Find the minimum value of _m for which the absolute value of is less than or equal to a predetermined allowable value. Also, after obtaining the sequence of equation (32),

Find the minimum m value _mb for which the absolute value of is less than or equal to a predetermined allowable value. Next, Q _k and R _{k are determined by setting the larger value of ma and m b to} k. Here, as for _rm , _rm is first obtained by m= _ma , and if its absolute value is less than a predetermined allowable value, _ma is set to k. If the absolute value is not less than the predetermined allowable value, the value of m is increased by +1 from _ma , and the minimum value of m at which the absolute value of _rm is less than the predetermined allowable value is defined as k.

の演算で求めたＬの値に基づいてワークの漏れの有無を判断する。Ｌの絶対値が所定の許容値以下ならば漏れ無し(合格品)と判定し、Ｌの絶対値が許容値を超えるならば漏れあり（不合格品）と判定する。 and,

Based on the value of L obtained by the calculation of , the presence or absence of work leakage is determined. If the absolute value of L is equal to or less than a predetermined allowable value, it is determined that there is no leakage (accepted product), and if the absolute value of L exceeds the allowable value, it is determined that there is leakage (rejected product).

If either m _a or m _b cannot be obtained, that is, if the absolute values of q _m and r _m do not converge below the allowable value, the measurement period T _M is extended. On the other hand, if k can be determined, the subsequent measurement period _TM is set based on the value of k. For example, the value of k (or a value obtained by adding a small margin (1 or 2) to this value) may be used as a new M to determine the measurement period _TM . In this way a minimum measurement period can be set.

This measurement period _TM may be used in subsequent tests on other workpieces of the same product. Also, in the calculation, the final gradients Q _M-1 and R _M-1 are obtained, and leakage can be determined from L _M-1 .

As described above, according to the present invention, once a large time constant is determined, leakage can be determined by simple four arithmetic operations without using the least squares method or simultaneous equations. In addition, it is possible to set the shortest measurement period _TM by judging whether the measurement period _TM is excessive or insufficient. Also, the theoretical basis for determining no leakage is clear.

Although the embodiments of the present invention have been described above with reference to the drawings, the specific configurations are not limited to those shown in the embodiments, and modifications and additions may be made without departing from the scope of the present invention. is also included in the present invention.

In the embodiment, the gas introduced from the pressure source to the work 2 and the master 3 is air, but it may be other than air, and may be nitrogen. However, steam is not good.

The present invention includes not only a leak inspection system but also a program executed by an information processing device of the leak inspection system.

The leak inspection device 10 shown in the embodiment is merely an example, and is not limited to this, and any inspection device that can carry out test pressure sealing measurement following atmospheric pressure sealing measurement may be used.

In the embodiment, calculations other than the calculation for obtaining the large time constant are performed on the leak test device 10 side. The information processing device 60 may perform some or all of the calculations that were previously performed. For example, the measurement data obtained in the atmospheric pressure sealing measurement process, the measurement data obtained in the test pressure sealing measurement process, and the setting values of various measurement conditions are transferred from the leak inspection device 10 to the information processing device 60, and the information processing device 60 All or part of the computation determination step may be performed in , or the final leak determination result may be obtained and displayed by the information processing device 60 .

Data exchange between the information processing device 60 and the leak test device 10 may be performed via a recording medium, or may be manually input in addition to communication. In the embodiment, the large time constant and the value of β obtained by the information processing device 60 are manually input to the leak test device 10. can be

2 Workpiece 3 Master 5 Leak inspection system 10 Leak inspection device 11 Pressure source connection port 12 Work connection port 13 Master connection port 14 Exhaust port 21 First pipe 22 Second pipe 23 Second pipe 3 piping 24 fourth pipeline 31 first on-off valve 32 second on-off valve 33 third on-off valve 34 fourth on-off valve 37 differential pressure gauge 40 inspection processing unit 41 control unit 42 storage unit 43 Operation panel 44 Operation input unit 45 Display unit 46 Valve control I/F
47... Differential pressure gauge I/F
48... Communication unit 49... Recording medium I/F
60... Information processing device 61... CPU
62... Storage unit 63... Communication unit 64... User I/F
65 Operation input unit 66 Display unit 67 Recording medium I/F

Claims (13)

A leak inspection system having a leak inspection device and an information processing device,
The leak inspection device is
Repeatedly measure the differential pressure between the container to be inspected and the leak-free reference container after both are sealed from the atmospheric pressure _PE release for a predetermined period, and correspond each measured differential pressure with the measurement time. perform an atmospheric pressure sealing measurement step that is recorded with
After the end of the atmospheric pressure sealing measurement step, gas is introduced into the inspection object container and the reference container, and after pressurizing them to a predetermined test pressure _PT , both are sealed, and after sealing, Repeatedly measuring the differential pressure between the internal pressures of both containers over a predetermined period of time, performing a test pressure sealing measurement step of correlating and recording each measured differential pressure and the measurement time,
From the data recorded in the atmospheric pressure sealing measurement step, the measurement time T in the atmospheric pressure sealing measurement step of the differential pressure data when the rate of change of the differential pressure over time becomes less than a certain value a first gradient acquisition step of obtaining _a and the rate of change Q of the differential pressure at that time;
From the data measured in the test pressure seal measurement step, the measurement time T of the differential pressure data in the test pressure seal measurement step when the change rate of the differential pressure with the passage of time becomes less than a certain value a second gradient acquisition step of obtaining _b and the rate of change R of the differential pressure at that time;
Let _TS be the time difference when measuring continuously from the measurement time _Ta to the measurement time _Tb ,

L is obtained as a value indicating the degree of leakage of the container to be inspected by the above calculation, or the presence or absence of leakage from the container to be inspected is determined by comparing the value of L obtained by the above calculation with a predetermined allowable value. a decision step;
and
The leak inspection device is
After sealing both the leak-free reference container and the leak-free test container at a temperature different from the surroundings from the release of the atmospheric pressure _PE , measure the pressure difference between the two containers for a certain period of time. performs a preparatory measurement step of continuously repeating the process of opening both containers to the atmospheric pressure _PE again a plurality of times, and outputs the measurement data obtained in the preparatory measurement step to the information processing device;
The information processing device is
After the container to be inspected and the reference container are sealed from atmospheric pressure _PE release based on the measurement data acquired from the leak inspection device or the measurement data excluding the first predetermined number of times of the measurement data Derive the large time constant, which is the time constant of the change in the pressure difference between the internal pressures of both containers,
The leak inspection device is
A leak inspection system, wherein the large time constant obtained by the information processing device is input, and in the determination step, the value of L is calculated using the input large time constant. A leak inspection system having a leak inspection device and an information processing device,
The leak inspection device is
After the container to be inspected and the reference container without leakage are sealed from the atmospheric pressure _PE release, the differential pressure between the internal pressures of both containers is repeatedly measured over the measurement period _TM , and each measured differential pressure is measured from the start of measurement. perform an atmospheric pressure sealing measurement step that is recorded together with the order of
After the end of the atmospheric pressure sealing measurement step, gas is introduced into the inspection object container and the reference container to pressurize to a predetermined test pressure _PT , and then, in the atmospheric pressure sealing measurement step After the compressed air introduction time _{TI has elapsed from the end of the measurement period TM ,} both are in a sealed state, and the differential pressure between the internal pressures of both containers after sealing is repeatedly measured over the measurement period _TM . performing a test pressure sealing measurement step of recording the pressure along with the order from the start of the measurement;
The data recorded in the atmospheric pressure sealing measurement step is divided into groups for each time T from the time of sealing (group number m = 1, 2, ... M), and the average value of the differential pressure for each group is divided by the time T , P _{ED, m} (m=1, 2, . . . M),

a first gradient obtaining step for obtaining a difference sequence of
The data recorded in the test pressure sealing measurement step is divided into groups for each time T from the time of sealing (group number m = 1, 2, ... M), and the average value of the differential pressure for each group is divided by the time T , P _{DD, m} (m=1, 2, . . . M),

a second gradient obtaining step for obtaining a difference sequence of
Let _TS be the sum of the measurement period _TM and the compressed air introduction time _TI ,

When the value of _Lm converges to a constant value as _m increases in the numerical sequence of a leakage judgment step of judging that there is no leakage when there is m that is equal to or less than the allowable value;
and
The leak inspection device is
After sealing both the leak-free reference container and the leak-free test container at a temperature different from the surroundings from the release of the atmospheric pressure _PE , measure the pressure difference between the two containers for a certain period of time. performs a preparatory measurement step of continuously repeating the process of opening both containers to the atmospheric pressure _PE again a plurality of times, and outputs the measurement data obtained in the preparatory measurement step to the information processing device;
The information processing device is
After the container to be inspected and the reference container are sealed from atmospheric pressure _PE release based on the measurement data acquired from the leak inspection device or the measurement data excluding the first predetermined number of times of the measurement data Derive the large time constant, which is the time constant of the change in the pressure difference between the internal pressures of both containers,
The α2 _is

and
The leak inspection device is
inputting the large time constant obtained by the information processing device, obtaining the _α2 based on the input large time constant,
The leak inspection system, wherein in the determination step, the value of _Lm is calculated using the input large time constant and _α2 . The leak inspection device is
In the leak determination step, if the absolute value of L _M-1 exceeds the allowable value,

The leak inspection system according to claim 2, wherein when _Dm converges to 0, it is determined that there is a leak. The leak inspection system according to claim 3, wherein when _Dm does not converge to 0, the measurement period _TM is extended, and the measurement is repeated from the atmospheric pressure sealing step. The leak inspection system according to any one of claims 2 to 4, wherein the measurement period TM is set based on the minimum _m at which _Lm converges. A leak inspection system having a leak inspection device and an information processing device,
The leak inspection device is
After the container to be inspected and the reference container without leakage are sealed from the atmospheric pressure _PE release, the differential pressure between the internal pressures of both containers is repeatedly measured over the measurement period _TM , and each measured differential pressure is measured from the start of measurement. perform an atmospheric pressure sealing measurement step that is recorded together with the order of
After the end of the atmospheric pressure sealing measurement step, gas is introduced into the inspection object container and the reference container to pressurize to a predetermined test pressure _PT , and then, in the atmospheric pressure sealing measurement step After the end of the measurement period _TM and the passage of the compressed air introduction time _TI , both are in a sealed state, and the differential pressure between the internal pressures of both containers after sealing is repeatedly measured over a predetermined period, and each measured differential pressure is recorded along with the order from the start of measurement, performing a test pressure sealing measurement step,
The data recorded in the atmospheric pressure sealing measurement step is divided into groups for each time T from the time of sealing (group number k = 1, 2, ... M), and the average value of the differential pressure for each group is divided by the time T , P _{ED, m} (m=1, 2, . . . M),

As

a first gradient acquisition step of determining the minimum value of _m for which the absolute value of is less than or equal to a predetermined allowable value;
The data recorded in the test pressure sealing measurement step is divided into groups for each time T from the time of sealing (group number m = 1, 2, ... M), and the average value of the differential pressure for each group is divided by the time T , P _{DD, m} (m=1, 2, . . . M),

As

A second gradient obtaining step of obtaining the minimum m value m _b for which the absolute value of is equal to or less than a predetermined allowable value, and obtaining Q _k and R _k , where k is the larger value of m _a and m _b and,
Let _TS be the sum of the measurement period _TM and the compressed air introduction time _TI ,

L is obtained as a value indicating the degree of leakage of the container to be inspected by the above calculation, or the presence or absence of leakage from the container to be inspected is determined by comparing the value of L obtained by the above calculation with a predetermined allowable value. a decision step;
and
The leak inspection device is
After sealing both the leak-free reference container and the leak-free test container at a temperature different from the surroundings from the release of the atmospheric pressure _PE , measure the pressure difference between the two containers for a certain period of time. performs a preparatory measurement step of continuously repeating the process of opening both containers to the atmospheric pressure _PE again a plurality of times, and outputs the measurement data obtained in the preparatory measurement step to the information processing device;
The information processing device is
After the container to be inspected and the reference container are sealed from atmospheric pressure _PE release based on the measurement data acquired from the leak inspection device or the measurement data excluding the first predetermined number of times of the measurement data Derive the large time constant, which is the time constant of the change in the pressure difference between the internal pressures of both containers,
The α2 _is

and
The leak inspection device is
inputting the large time constant obtained by the information processing device, obtaining the _α2 based on the input large time constant,
The leak inspection system, wherein in the determination step, the value of L is calculated using the input large time constant and _α2 . If _either ma or _mb cannot be obtained, the measurement period _TM is extended, and if k can be determined, the subsequent measurement period _TM is set based on the value of k. The leak inspection system according to claim 6. A leak inspection system having a leak inspection device and an information processing device,
The leak inspection device is
After the container to be inspected and the reference container without leakage are sealed from the atmospheric pressure _PE release, the differential pressure between the internal pressures of both containers is repeatedly measured over the measurement period _TM , and each measured differential pressure is measured from the start of measurement. perform an atmospheric pressure sealing measurement step that is recorded together with the order of
After the end of the atmospheric pressure sealing measurement step, gas is introduced into the inspection object container and the reference container to pressurize to a predetermined test pressure _PT , and then, in the atmospheric pressure sealing measurement step After the end of the measurement period _TM and the passage of the compressed air introduction time _TI , both are in a sealed state, and the differential pressure between the internal pressures of both containers after sealing is repeatedly measured over a predetermined period, and each measured differential pressure is recorded along with the order from the start of measurement, performing a test pressure sealing measurement step,
The data recorded in the atmospheric pressure sealing measurement step is divided into groups for each time T from the time of sealing (group number k = 1, 2, ... M), and the average value of the differential pressure for each group is divided by the time T Let the values be P _ED,m (m=1, 2, . . . M),

a first gradient acquisition step of determining
The data recorded in the test pressure sealing measurement step is divided into groups for each time T from the time of sealing (group number m = 1, 2, ... M), and the average value of the differential pressure for each group is divided by the time T Let the values be P _DD,m (m=1, 2, . . . M),

a second gradient acquisition step of determining
Let _TS be the sum of the measurement period _TM and the compressed air introduction time _TI ,

L is obtained as a value indicating the degree of leakage of the container to be inspected by the above calculation, or the presence or absence of leakage from the container to be inspected is determined by comparing the value of L obtained by the above calculation with a predetermined allowable value. a decision step;
and
The leak inspection device is
After sealing both the leak-free reference container and the leak-free test container at a temperature different from the surroundings from the release of the atmospheric pressure _PE , measure the pressure difference between the two containers for a certain period of time. performs a preparatory measurement step of continuously repeating the process of opening both containers to the atmospheric pressure _PE again a plurality of times, and outputs the measurement data obtained in the preparatory measurement step to the information processing device;
The information processing device is
After the container to be inspected and the reference container are sealed from atmospheric pressure _PE release based on the measurement data acquired from the leak inspection device or the measurement data excluding the first predetermined number of times of the measurement data Derive the large time constant, which is the time constant of the change in the pressure difference between the internal pressures of both containers,
The α2 _is

and
The leak inspection device is
inputting the large time constant obtained by the information processing device, obtaining the _α2 based on the input large time constant,
The leak inspection system, wherein in the determination step, the value of L is calculated using the input large time constant and _α2 . 10. The method according to any one of claims 1 to 8, wherein information is exchanged between the leak inspection device and the information processing device by using one or more of communication, recording media, and manual input operation. A leak test system according to any one of the preceding claims. 10. The leak according to any one of claims 1 to 9, wherein the leak inspection device includes an operation panel, and the operation panel receives an input operation of the large time constant derived by the information processing device. inspection system. The measurement period in the atmospheric pressure sealing measurement step is TM, and both the inspection object container and the reference container are applied to the test pressure in the test pressure sealing measurement step from the end of the measurement period in the atmospheric pressure sealing step. Let TI be the compressed air introduction time, which is the time until it is compressed and sealed,
The information processing device, instead of the large time constant,
β = exp (-(TM + TI) / large time constant)
and derive
The leak inspection system according to any one of claims 1 to 10, wherein the leak inspection device inputs the β derived by the information processing device and uses it for calculation. A program executed by an information processing device in the leak inspection system according to any one of claims 1 to 10,
inputting the measurement data from the leak test device;
Based on the measurement data, one of the two time constants governing the temperature-based change in the pressure difference between the internal pressures of the container to be inspected and the reference container after the containers are sealed from the atmospheric pressure _PE deriving the larger time constant, the large time constant;
an output step of outputting the derived large time constant;
A program with A program executed by an information processing device in the leak inspection system according to claim 11,
inputting the measurement data from the leak test device;
Based on the measurement data, one of the two time constants governing the temperature-based change in the pressure difference between the internal pressures of the container to be inspected and the reference container after the containers are sealed from the atmospheric pressure _PE obtaining the large time constant, which is the larger time constant, to derive the β;
an output step of outputting the derived β;
A program with

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