JP2001311678A - Method for judging presence/absence of air leak of sealed container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for judging the presence or absence of an air leak in a sealed container wherein a judgment accuracy can be maintained by reducing misjudgments even when the measurement environment changes or a measuring apparatus changes with time. SOLUTION: A CPU 30 included in a judging body part 20 measures pressure for judging a leak. Every time sealed container is judged as a good product without any air leak, an average-calculating part 42 calculates a moving average value of a predetermined number of measured pressure values including the latest data. A judging value-calculating part 44 adds a judgment allowance value to the moving average value and calculates an updated judging value. While sequentially updating the updated judging value, the CPU 30 judges a leak on the basis of the judging value which follows the change with time of the measurement environment and the measuring apparatus.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for judging the presence or absence of air leaks in a closed container, and more particularly to the method for judging the presence or absence of air leaks in a closed container. It relates to the improvement of the presence / absence determination method.

[0002]

2. Description of the Related Art For example, a sealed relay or the like which is a microelectronic component has a movable contact and an exciting coil housed in a plastic container, and by sealing this container, a sealed small and small power relay element can be obtained. . By sealing such a sealed relay, air or inert gas sealed in the container keeps the movable parts and other internal parts of the relay in a stable state, and the internal parts are affected by dust and the like. As a result, the stable operation characteristics of the microelectronic component can be maintained for a long period of time. Of course, the sealed container can be applied not only to the microelectronic component as described above, but also to medical, food, and other wide fields, and can stabilize and protect objects in the sealed container.

[0003] Such a hermetically sealed container may not be able to maintain a completely sealed state due to poor sealing at the time of manufacture, breakage of the container itself, or the presence of through holes or the like. Such a hermetically sealed container whose airtightness has been impaired must be reliably removed as a defective product having an air leak.
In order to make this determination, several methods for determining the presence or absence of air leak have been proposed.

For example, in a determination method called a differential pressure type,
Two sealed tanks connected to each other with a pressure balance detector interposed therebetween are prepared. One sealed tank stores a sealed container to be measured, and the other sealed tank stores a reference sealed container without air leak.
In this state, each closed tank is depressurized or pressurized to form the same constant pressure space. If a leak exists in the measured closed container, the internal space of the measured closed container is assimilated with the internal space of the closed tank, and the pressure balance between the two closed tanks is lost. By detecting the collapse, it is possible to determine whether or not there is a leak. However, in the case of this method, a sufficient equilibration time is required to stabilize the pressure in the two closed tanks, and the inspection time cannot be reduced, or in order to stabilize the internal pressure of the closed tank, There is a disadvantage that a sufficiently large pressurizing source or depressurizing source is required, and the apparatus becomes large. In addition, in the case of non-complete leaks that gradually leak air after the pressure in the sealed tank is stabilized, so-called small leaks and medium leaks, the imbalance in pressure can be detected. However, complete leaks (large leaks due to large holes etc. If there is a leak, the internal space of the container to be measured is already assimilated with the internal space of the closed vessel at the start of pressurization or depressurization, so there is a possibility that a complete leak cannot be detected accurately.

On the other hand, there is a determination method called a direct pressure type. In this method, first, a sealed container to be measured, which is a leak detection target, is charged into a measurement tank having a predetermined volume, and the measurement tank is sealed to have a predetermined initial tank pressure. Thereafter, the initial tank pressure is changed by a predetermined amount. The change in the predetermined amount of the pressure may be performed by changing the volume of the measurement tank from the predetermined volume in a closed state, or may be performed by some means while maintaining the volume of the measurement tank in the closed state at the predetermined volume. It may be carried out under pressure or reduced pressure. Then, the pressure change after the start of the change of the predetermined amount in the measuring tank is measured. At this time, if an air leak exists in the measured closed container, the pressure change is different from the case where no air leak exists. According to this method, when an air leak exists in the closed container to be measured, the internal space of the closed container to be measured is assimilated with the internal space of the measuring tank, and the substantial internal volume increases (the volume of the measuring tank is reduced). Even when the pressure is changed by a predetermined amount by changing the pressure, the pressure further changes with respect to the changed volume), and the pressure during measurement rises (when the measurement tank is depressurized) or falls with respect to the case where there is no air leak. (When the measuring tank is pressurized). The presence or absence of an air leak is determined based on this pressure change. At this time, since it is not necessary to stabilize the pressure balance in preparation for measurement, it is possible to make a quick determination with a simple configuration in which the pressure in the measurement tank is only changed by a predetermined amount. In addition, since the determination is made based on the change in the pressure of the measurement tank, any of the large leak, the medium leak, and the small leak can be determined.

[0006]

According to the above-described direct pressure type determination method, small, medium, and large leaks can be determined quickly and easily with a simple configuration.
The pressure in the measurement tank, which serves as a criterion for determination, is greatly affected by changes in the measurement environment. In particular, when performing a small leak determination that performs a leak determination based on a slight pressure change, even if the measured pressure difference fluctuates slightly due to a change in the absolute humidity or the like, it deviates from the set determination value. Conventionally, since a fixed value is used as the determination value, for example, a measured closed container that should be originally determined to be a good product may be determined to be a defective product. Conversely, a defective product may be determined as a non-defective product. If the determination is made in a strictly controlled measurement room or the like, the above-described erroneous determination can be reduced, but it is very difficult to strictly control the actual environment of the production line. Furthermore, in a measurement system including a measurement tank, a sealed state is formed by a seal member or the like. However, the sealed state may fluctuate due to aging, which may cause the same erroneous determination as described above. In addition, when the measurement pressure changes due to a change in the determination environment, the failure determination is often performed continuously, and the worker is forced to confirm the failure and check the measurement system each time, thereby increasing the worker load. There is also a problem of inviting.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and has as its object to reduce erroneous determination even when a change in the measurement environment or a change in the measuring device with time, that is, a change in the determination environment, is achieved. An object of the present invention is to provide a method for judging the presence or absence of air leak in a closed container which can maintain accuracy and reduce a load on an operator.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a method in which a sealed container to be measured is placed in a measuring tank having a predetermined initial tank pressure and a closed space having a predetermined volume. A method for determining the presence or absence of air leak in a sealed container to be measured based on a pressure change value of the pressure in the measurement tank when the initial pressure in the tank is changed by a predetermined amount. Calculating an average value of the pressure change values of the predetermined number of sealed containers to be measured determined to be absent, and adding an allowance margin value to the average value to calculate an update determination value; and Determining the sealed container to be measured, and including the pressure change value of the measured sealed container determined to have no air leak as the latest data for calculating the average value.

According to this configuration, the average value is constantly updated using the latest pressure change value determined as a non-defective product. Therefore, even if the measurement pressure changes due to a change in the measurement environment or a change with time in the measurement device. In addition, it is possible to obtain the updated determination value by adding the determination margin value to the average value in consideration of the variation, thereby preventing erroneous determination.

In order to achieve the above object, the present invention is characterized in that, in the above-mentioned configuration, the method includes a step of changing at least the number of calculation data of the average value or the setting of the judgment allowance value according to the measurement situation. And

According to this configuration, the determination accuracy can be easily adjusted.

[0012] In order to achieve the above object, the present invention is characterized in that, in the above configuration, a step of outputting an alarm when the update determination value is updated beyond an abnormal update value is provided. .

Here, the abnormal update value is a limit value of the update value of the determination, and is a value which is not exceeded by a change in the normal measurement environment, for example, a pressure change due to a change in humidity, temperature, or the like. That is, if the value exceeds the abnormal update value, there is a possibility that the sealing failure due to the deterioration of the measuring device with time or the pressure change due to the decrease in the sensor accuracy. According to this configuration, it is possible to easily find a failure of the measuring device while preventing erroneous determination, and it is possible to continuously and smoothly determine whether or not there is an air leak.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention (hereinafter referred to as embodiments) will be described below with reference to the drawings.

FIG. 1 is a schematic explanatory diagram for explaining the basic configuration concept of an air leak detection device 10 for realizing the air leak presence / absence determination method of the present embodiment. The air leak detection device 10 shown in FIG. 1 is a direct pressure type air leak detection device, which is of a type that depressurizes the measurement tank in order to change the pressure in the measurement tank by a predetermined amount. In other words, the air leak detection device 10 includes a measurement tank 14 for housing and inspecting a sealed container to be measured, for example, a seal relay (hereinafter, referred to as a work) 12 as a microelectronic component, and a plurality of switching valves (for In the embodiment, four switching valves Va, Vb, V
c, Vd), a pressure sensor 18 disposed near the measuring tank 14 and capable of detecting a pressure in the measuring tank 14, a depressurizing apparatus 16, and a pressure sensor 1.
8. It is composed of a determination main unit 20 and the like including a determination unit which performs control on the control of each switching valve Va, Vb, Vc, Vd, and the like, and performs a predetermined determination output.

The measuring tank 14 is, for example, an openable and closable case composed of an upper case 14a and a lower case 14b connected by a hinge or the like. The upper case 14a and the lower case 14b
A measurement chamber 22 for accommodating the work 12 is formed substantially at the center in a state in which are joined (closed state). For example, an O-ring 24 is arranged around the measurement chamber 22 as an airtight seal member in order to secure airtightness of the measurement chamber 22 in a closed state. Therefore, the measurement chamber 22 having a substantially closed space with a predetermined volume is formed by the upper housing 14a and the lower housing 14b.
Can be formed. Note that the entire upper housing 14a and lower housing 14b or the inner wall surface is formed of metal, hard resin, or the like so that the inner wall surface of the measurement chamber 22 is not deformed due to a pressure change or the like.

On the other hand, the pressure reducing device 16 is provided with the vacuum pump 1
The pressure reducing tank 16c includes a pressure reducing tank 16c having a pressure regulator 6a and a regulator 16b, so that the inside of the pressure reducing tank 16c can always be maintained at a predetermined pressure. Further, the switching valves Va, Vb,
Vd selectively opens and closes a flow path 26 that connects and connects the measurement tank 14 and the pressure reducing device 16. In particular, the switching valve Va
The space formed between the pressure chamber and the switching valve Vb defines a reference pressure chamber 28 capable of forming a different pressure state with respect to the measurement tank 14. The switching valve Vc is a valve for opening to the atmosphere, and is provided with the flow path 26 and the measurement chamber 2 of the measurement tank 14.
Opened when the pressure of 2 is released to the atmosphere.

On the other hand, the determination main unit 20 includes a control operation unit (C
PU) 30, the CPU 30 has a display 32 for displaying various information including determination progress, determination results, and other alarms, a memory 34 for storing various data in the determination progress, determination results, and the like, It includes a setting unit 36 for performing various settings, a control input / output unit 38 for mainly controlling the opening and closing of the switching valves Va, Vb, Vc, Vd, an A / D converter 40 for digitally converting the measured value of the pressure sensor 18 and the like. .

FIG. 2 shows a pressure change when the air leak detection device 10 performs a pressure measurement according to a procedure described later when the air leak of the work 12 is determined.
In addition, the pressure change shown in FIG. 2 is a pressure change when a measurement is performed on a good product.

When the air leak of the work 12 is determined,
First, as preparation for determination, the work 12 to be determined is put into the measurement chamber 22 of the measurement tank 14. At this time, the judgment body 20
Opens only the switching valves Va and Vb, and connects the measuring tank 14 with the reference pressure chamber 28 defined by the switching valves Va and Vb. Subsequently, the upper housing 14a and the lower housing 1 of the measurement tank 14
4b is brought into close contact (lid closing operation) to bring the measuring tank 14 into a substantially sealed state. Since the internal pressure of the space including the measurement chamber 22 increases due to the lid closing operation,
Opens the switching valve Vc following the switching valves Va and Vb, and sets the pressure in the measurement chamber 22 and the reference pressure chamber 28 to the atmospheric pressure (P0 = 1013 × 10 ² Pa). Next, the switching valves Va and Vc are closed, and the switching valve Vd is opened. By this operation, the space including the reference pressure chamber 28 is
And is controlled by the decompression device 16. At this time, in the pressure reducing device 16, for example, PV = 0.4 kgf / cm
² (392 × 10 ² Pa). In this state, the switching valves Vb and Vd are closed. That is, all the switching valves are closed, and the reference pressure state value P1 (from atmospheric pressure to 392 ×
The reference pressure chamber 28 having a predetermined volume of (10 ² Pa reduced pressure) is formed, and the determination main unit 20 completes the measurement preparation.

When a measurement start signal is given to the judgment main body 20, only the switching valve Va is opened, and the measuring tank 14 (measuring chamber 22) and the reference pressure chamber 22 are communicated.
The internal pressure of the (measurement chamber 22) is changed (reduced pressure) (FIG. 2).
Elapsed time A).

The determination main unit 20 controls the pressure sensor 18 in a state where only the switching valve Va is opened, and
And the pressure in the measurement chamber 22 at the time point C. Subsequently, the determination main unit 20 opens the switching valves Va, Vb, and Vd for a predetermined time (for example, between elapsed times CD) and sets the measurement chamber 2
2 is reduced to the initial reference pressure state value P1 of the reference pressure chamber 28, the switching valve Va is closed, and after a lapse of a predetermined time (elapsed time E), the pressure (PXd) of the measurement chamber 22 is measured. At this time, if there is no air leak in the work 12, the measurement value of the pressure sensor 18 in the measurement chamber 22 becomes PXd = PV. Further, the determination body 20 determines the pressure (PXc) of the measurement chamber 22 after a predetermined time (elapsed time F, for example, 2 seconds) after the measurement of PXd.
Is measured, and the pressure measurement for air leak determination is completed.

As described above, the air leak of the work 12 includes a large leak, a medium leak, and a small leak. The detection of each leak can be performed by comparing the pressure ratio based on each measured value with the reference pressure ratio, and the reference pressure change of the non-defective product (reference product) as shown in FIG. Can also be performed by comparing For example, when there is a large leak (a large hole is formed in the work 12 and leaks at the same time as the communication with the reference pressure chamber 22), the pressure change value between the elapsed times A and C in FIG. Slide in the direction. Further, in the case of a medium leak (not a large hole but a remarkable leak), the pressure change gradient in the short time between the elapsed times B and C becomes larger than the reference pressure change. Further, in the case of a small leak (a minute hole, and the leak occurs slowly), the pressure change gradient over a relatively long time between the elapsed times EF becomes larger than the reference pressure change.

As described above, a good product (without air leak) and a defective product (with air leak) can be determined by comparing measured pressures. Therefore, in consideration of the variation in the shape of the work 12, etc., a judgment value in which a predetermined judgment allowance value is added to the reference pressure is set, and the judgment value is compared with the measured value to judge whether or not there is an air leak. Accuracy.

The pressure changes due to fluctuations in the measurement environment such as humidity and temperature, aging of the measurement device, and the like. The influence of the pressure change based on the change of the determination environment greatly affects the small leak determination in which a slight pressure change is observed for a relatively long time. In other words, when the measured pressure value increases or decreases due to a change in the determination environment, the work 12 that has fallen within the allowable range based on the fixed determination value is determined to be a defective product having a leak, or conversely, a defective product. Is determined to have no leak.

Therefore, in the present embodiment, a judgment value in consideration of a change in the judgment environment is adopted. In order to consider a change in the determination environment in the determination value, in the present embodiment,
Each time a non-defective item is determined, the determined value is updated using the pressure measurement value at that time. Specifically, an average value of a predetermined number of pressure measurement values including the latest pressure measurement value is obtained, and a judgment margin value is added to the average value to calculate a judgment value. Therefore, the CPU 30 of the determination main unit 20 illustrated in FIG. 1 includes an average value calculation unit 42 and a determination value calculation unit 44.

FIG. 3 shows a specific procedure for calculating a judgment value (update judgment value) performed by the judgment main unit 20. FIG. 4 is an explanatory diagram illustrating generation of an update determination value and a concept of determination based on the generation.

First, a reference product is measured in preparation for calculating an update determination value (S100). This reference product is the work 12 for which it has been confirmed that there is no air leak at all, and is performed in an environment where a normal determination is made in the above-described procedure. Then, a measured pressure value (pressure change amount) P0 (see FIG. 4) in the small leak detection period (elapsed time EF in FIG. 2) is calculated (S101). Subsequently, an initial determination value J0 is determined based on the calculated measurement value (S102). The initial judgment value J0 is a judgment value that is valid until the update judgment value can be calculated, and a predetermined judgment margin value (a management width in consideration of the measurement value variation due to the shape variation of the work 12, etc.) is added to the measurement value P0. Is added. This initial judgment value J
0 is a fixed value set by the operator with the setting device 36 in FIG. 1 (the horizontal portion of the determination line L0 in FIG. 4).

Then, the judgment main unit 20 sets the initial judgment value J
The leak determination is performed for the work 12 until the non-defective data of a predetermined number of samples (for example, 50) set by the setting unit 36 based on 0 is accumulated, and only the measured values of the non-defective work 12 are sequentially determined. It is stored in the memory 34 (S1
03). In FIG. 4, the work 12 in which a pressure change amount higher than the determination line L0 (at this time, only the parallel portion) is detected is a defective product (x display).

On the other hand, an average value calculation section 42 included in the CPU 30 always reads data from the memory 34 and calculates an average value. Then, when data of a predetermined number of samples can be obtained, the initial average value is determined, the judgment margin value is added to the initial average value, and an update judgment value J1 is generated (S104). Is updated to the update determination value J1 (S105). As described above, until the update determination value J1 is generated, the leak determination is performed based on the fixed initial determination value J0. The amount of pressure change calculated at this time depends on the current determination environment (current humidity And the environment based on the temperature and the state of the measuring device), the update determination value J1 includes the determination environment.

When the CPU 30 obtains the update judgment value J1,
Leak determination is performed based on the updated determination value J1, and when it is determined to be non-defective (S106), data of a predetermined number of samples including the latest pressure measurement value (latest data) acquired at the time of performing the non-defective determination, that is, , 50 samples used
If the number is set as the number of data, the average value calculation unit 42 determines the moving average value (finally, FIG. 4) based on the 50 data including the second to 50th data acquired in (S103). Then, the judgment value calculation unit 44 calculates an update judgment value J2 to which the judgment margin value is added (S107). Then, the CPU 30 updates the update determination value J1 used as the determination criterion to the update determination value J2 (S1).
08).

Similarly, every time a non-defective item is determined based on the updated update determination value, the moving average value is updated by the average value calculation unit 42 and the update determination value (J3 ·・ ・) Is generated and updated. as a result,
Leak determination can be performed based on a determination value that follows the determination environment. Of course, at this time, for a defective product having a leak, only data is stored as necessary, and the data is not used for updating the determination value. Also, the transition data as shown in FIG. 4 may be displayed on the display 32 to monitor the determination state. By performing such a display, the operator can easily grasp the change in the determination environment and can easily perform the air leak determination management.

As described above, by sequentially generating the update determination value and repeating the update, it is possible to obtain the determination line L0 substantially following the change of the determination environment as shown in FIG. As a result, erroneous determination of the presence / absence of a leak due to a change in the determination environment is reduced as compared with the case where the determination is performed based on the fixed determination value, and the management load of the measurer can be reduced. Since the number of samples when calculating the moving average value can be changed by the setting unit 36, a stable and highly reliable update determination value can be obtained by increasing the number of samples while considering the balance with the operation load of the apparatus. It is also possible to obtain. In addition, the management width can be appropriately changed by the setting device 36, so that the determination accuracy can be easily adjusted.

As described above, when the generation of the update determination value is repeated based on the pressure measurement value, performance degradation due to a change with time on the air leak detection device 10 side, for example, poor sealing of the measurement tank 14, switching valve Va, etc. In the case where the operation failure of the pressure sensor 18 or the decrease in accuracy of the pressure sensor 18 occurs, the update determination value sequentially changes. For example, the determination lines L1, L2,
In some cases, it is indicated by L3 or the like. In such a case,
If the cause is an abnormality on the side of the air leak detection device 10, the reliability of the determination result decreases. Therefore, in order to detect such a suspicion of a device abnormality, the air leak detection device 10 of the present embodiment sets an abnormal update value to the update determination value. In the case of FIG. 4, the upper limit abnormal update value is indicated by a line S1, and the lower limit abnormal update value is indicated by a line S2.
When the update determination value is calculated beyond the lines S1 and S2, the determination body unit 20 determines that the determination is abnormal, and issues an alarm (a voice alarm such as a buzzer or a message, a screen display or a lamp) to prompt the user to stop the determination operation. (E.g., signal warning by lighting) or the like, and notifies the administrator of the air leak detection device 10. When the administrator confirms the alarm, the administrator, for example, checks the device. As a result, if an abnormality such as deterioration is present in the apparatus, the abnormal part is repaired, and then the setting from the initial determination value J0 is performed again according to the procedure shown in FIG. On the other hand, if no abnormality is observed on the device side, after confirming the measurement environment, if it can be determined that the change is caused by a change in the measurement environment, the lines S1 and S2 are corrected, and the determination is continued by the determination line L1 and the like I do. As described above, even when the determination value is automatically updated, it is possible to perform the maintenance and management of the apparatus performance and perform the leak determination with high reliability.

Although the present embodiment has been described with respect to the determination of a small leak that causes a slight pressure change in a relatively long time, the determination of a medium leak or a large leak is similarly performed while following the measurement environment. Is updated, the determination reliability can be improved as in the case of a small leak.

In this embodiment, as an example of a direct pressure type air leak detection device, the communication between the measurement tank and a reference pressure chamber capable of forming a different pressure state is switched,
The type in which the pressure of the measuring tank is changed by a predetermined amount while maintaining the volume of the measuring tank has been described as an example, but the pressure of the measuring tank is reduced or increased by changing the volume of the measuring tank from the predetermined volume. The same effect can be obtained by updating the determination value while following the measurement environment as described above at the time of air leak determination in the type of air leak detection device that changes a predetermined amount.

[0037]

According to the present invention, erroneous determination can be reduced even if the measurement environment changes or the measuring instrument changes over time, and the accuracy of leak determination for the sealed container to be measured can be maintained. . Further, the management burden on the worker can be reduced by reducing the erroneous determination.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating a configuration concept of an air leak detection device that realizes an air leak presence / absence determination method according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating an example of a pressure change when measurement is performed by an air leak detection device that realizes an air leak presence / absence determination method according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram illustrating a procedure for updating a determination value based on an air leak presence / absence determination method according to an embodiment of the present invention.

FIG. 4 is an explanatory diagram illustrating a transition of an update determination value based on an air leak presence / absence determination method according to the embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 10 air leak detection device, 12 work, 12a internal space, 14 measurement tank, 14a upper housing, 14b lower housing, 16 decompression device, 18 pressure sensor, 20 judgment main body, 22 measurement room, 22a residual space, 24 O
Ring, 26 flow paths, 28 reference pressure chambers, Va, Vb, V
c, Vd switching valve, 30 control operation unit (CPU), 3
2 display, 34 memory, 36 setting device, 38
Control input unit, 40 A / D converter, 42 average value calculation unit, 44 judgment value calculation unit.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hidekazu Yoshioka 10th Hanazono Todocho, Ukyo-ku, Kyoto, Kyoto Prefecture F-term in Omron Corporation (reference) 2G067 AA44 BB31 DD02 EE01

Claims (3)

[Claims] 1. A closed vessel to be measured is charged into a measuring tank having a predetermined initial tank pressure and having a closed space of a predetermined volume, and the inside of the measuring tank when the initial tank pressure is changed by a predetermined amount. A method for determining the presence or absence of air leak in a sealed container to be measured based on a pressure change value of a pressure, wherein the method is a method for determining the presence or absence of air leak in a sealed container. Calculating an update judgment value by adding a judgment allowance value to the average value, and judging a subsequent sealed container to be measured based on the update judgment value, and the measured sealed container determined to have no air leak. Including a step of including a pressure change value of the container as the latest data for calculating the average value. 2. The method according to claim 1, further comprising the step of changing at least the number of data calculated as an average value or the setting of a judgment allowance value according to a measurement situation. . 3. The method according to claim 1, wherein the update determination value is updated beyond an abnormal update value.
A method for determining the presence or absence of air leak in a closed container, comprising a step of outputting an alarm.