JP2006177810A - Inspection device and inspection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inspection device and an inspection method capable of improving inspection accuracy of airtightness. <P>SOLUTION: This inspection device 100 for inspecting airtightness of a product is characterized by being equipped with a pressure source 10 for sending the air into the product inside an inspection object product 200; an airtight container 20 capable of storing the inspection object product 200, while keeping airtightness in the container; and a flow rate sensor 30 for measuring the air leak quantity from the inspection object product 200 by measuring the quantity of the air flowing in an exhaust passage 21 connected to the airtight container 20 at the pressure sending time of the air by the pressure source 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an inspection apparatus and an inspection method for inspecting airtightness of a product.

  In general, the airtightness inspection of products is performed using a differential pressure method. FIG. 5 is a schematic diagram of an airtight inspection apparatus according to a conventional example.

  As shown in FIG. 5, an airtight inspection apparatus according to a conventional example includes a pressure source 300 that pumps air of the same pressure to both a product to be inspected 400 and a master 500, and a shutoff valve 601 provided in the middle of each pumping path. , 602, a pressure gauge 401 that measures the pressure drop inside the inspection target product 400, and a pressure gauge 501 that measures the pressure drop inside the master 500. The master 500 has a volume equivalent to that of the inspection target product 400 and serves as a reference for comparison.

  Using the airtight inspection apparatus configured as described above, the inspection is performed as follows. That is, first, air of the same pressure is pumped to both the inspection target product 400 and the master 500 by the pressure source 300. Then, after the internal pressure of the product 400 to be inspected is stabilized, the shutoff valves 601 and 602 block off the pressure feeding paths. Thereby, both the inspection object product 400 and the master 500 are sealed separately. Then, the pressure drops of the inspection target product 400 and the master 500 are measured by the pressure gauges 401 and 501, respectively. In this way, the airtightness of the inspection target product 400 is evaluated from the comparison result of the pressure drop between the inspection target product 400 and the master 500 (inspection of whether there is a certain amount of air leakage).

  When the above-described differential pressure type inspection method is used, the outer frame (sealed container or the like) of the product to be inspected 400 is expanded by the internal pressure during pneumatic feeding, so that the differential pressure with the master 500 is increased by the amount of expansion. May occur, or a differential pressure may be generated between the master 500 due to the properties of the components of the product 400 to be inspected. In addition, because the inspection target product 400 itself is too large, the internal pressure may not be stable during pneumatic feeding. Furthermore, there is a problem that it is easily influenced by the environment such as atmospheric pressure, temperature, and humidity at the time of inspection.

  For these reasons, accurate measurement is not always possible, and the evaluation of airtightness may not be sufficient. Therefore, the accuracy of the inspection was not sufficient.

  An object of the present invention is to provide an inspection apparatus and an inspection method that improve the accuracy of airtightness inspection.

  The present invention employs the following means in order to solve the above problems.

That is, the inspection apparatus of the present invention is
In inspection equipment that inspects the airtightness of products,
A pressure-feeding means for sending gas into the product of the product to be inspected;
An airtight container capable of storing a product to be inspected while keeping the inside of the container airtight;
Measuring means for measuring the amount of gas leaking from the product to be inspected by measuring the amount of gas flowing through the exhaust passage connected to the hermetic container at the time of gas feeding by the pressure feeding means;
It is characterized by providing.

  According to the configuration of the present invention, the amount of gas leakage from the product to be inspected is directly measured. Therefore, as in the case of the differential pressure method, the measurement error is reduced as compared with the case where the airtightness is evaluated based on the comparison with the measured value of the master.

  Moreover, it is good to provide the valve which releases the pressure in the said airtight container for a predetermined period from the pumping start by the said pumping means.

  That is, when the product to be inspected expands due to the internal pressure, the internal pressure in the airtight container changes. Due to the change in internal pressure in the airtight container, it is difficult to determine whether the gas flowing in the exhaust passage is due to leakage from the product to be inspected while the gas is flowing in the exhaust passage. Cannot be inspected. In particular, when the change in the internal pressure in the hermetic container lasts for a long period of time, the time required to start accurate measurement becomes longer. Therefore, by releasing the pressure in the hermetic container for a predetermined period from the start of pumping by the above-described valve, it is possible to quickly suppress the gas from flowing into the exhaust passage due to the pressure change in the hermetic container. . Thereby, the measurement of the amount of gas leakage from the product to be inspected can be started early.

  Moreover, it is good to provide the adjustment means which adjusts the amount of pressurization when gas is pumped into the inside of a product by the said pumping means.

  By providing such an adjusting means, it is possible to prevent the internal pressure of the inspection target product from rapidly increasing, and it is possible to prevent breakage of various members constituting the inspection target product.

  Moreover, it is good to provide the test | inspection means which test | inspects the leak amount of the gas from the said airtight container itself.

  By providing such an inspection means, it is possible to suppress measurement errors in the amount of gas leakage from the product to be inspected due to gas leakage from the airtight container itself.

Detection means for detecting the atmospheric pressure in the airtight container;
When the atmospheric pressure detected by the detection means exceeds a predetermined value, a pressure release means for releasing the pressure in the airtight container may be provided.

  By configuring in this way, it is possible to prevent the air pressure exceeding a predetermined level from being applied to the inside of the airtight container, the exhaust passage, the measuring means and the like. Therefore, it is possible to prevent breakage caused by applying a large internal pressure to these.

Moreover, the inspection method of the present invention includes:
In the inspection method for inspecting the airtightness of products,
Storing the product to be inspected in an airtight container in an airtight state;
A process of sending gas into the product to be inspected,
Measuring the amount of gas leaked from the product to be inspected by measuring the amount of gas flowing through the exhaust passage connected to the airtight container while the gas is being sent into the product. It is characterized by that.

  According to the inspection method of the present invention, since the amount of gas leakage from the product to be inspected is directly measured, measurement errors can be suppressed.

  Moreover, it is good to have the process of releasing the pressure in the said airtight container for a predetermined period after it starts sending gas into the product inside the product to be inspected.

  Further, when the pressure in the airtight container exceeds a predetermined value during the inspection, the pressure in the airtight container may be released.

  In addition, said each structure can be employ | adopted combining as much as possible.

  As described above, according to the present invention, the accuracy of airtightness inspection can be increased.

  The best mode for carrying out the present invention will be exemplarily described in detail below based on the embodiments and examples with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described in these embodiments and examples limit the scope of the present invention only to those unless otherwise specified. It is not intended.

(Embodiment 1)
<Inspection device>
With reference to FIG. 1, an inspection apparatus according to Embodiment 1 of the present invention will be described. FIG. 1 is a schematic diagram of an inspection apparatus according to Embodiment 1 of the present invention. As shown in the figure, the inspection apparatus 100 according to the first embodiment of the present invention includes a pressure source 10 as a pressure feeding unit that sends gas into the product of the inspection target product 200, and the inspection target product while keeping the inside of the container airtight. The airtight container 20 which can accommodate 200 and the flow sensor 30 as a measurement means which measures the amount of gas leaks from the test object product 200 are provided. The gas pumped from the pressure source 10 is fed directly into the product of the inspection target product 200 through the pumping passage T1. Further, an exhaust passage T <b> 2 is connected to a through hole 21 provided in the airtight container 20. A flow rate sensor 30 is provided on the exhaust passage T2. For example, a flow meter such as a mass flow meter can be used as the flow sensor 30. In addition, examples of the inspection target product 200 to be inspected in the first embodiment include products in the field of water treatment such as pressure vessels and water purifier cartridges, automobile parts, and other general industrial equipment parts. Can do.

<Inspection method>
An inspection method for inspecting the airtightness of the inspection target product 200 using the inspection apparatus configured as described above will be described. First, the inspection target product 200 is set in the airtight container 20, and the inside of the container is airtight. Next, a gas (air or the like) is sent into the product 200 to be inspected by the pressure source 10. Then, the flow rate of the gas flowing through the exhaust passage T2 is measured by the flow rate sensor 30 while the amount of pressurization by the pressure source 10 is kept constant.

  Since the inspection target product 200 is stored in the airtight container 20 in an airtight state, when a gas leaks from the product when the gas is sent into the inspection target product 200, the corresponding amount. Only the gas flows through the exhaust passage T2. Thereby, the amount of gas leakage from the inspection target product 200 can be directly measured by the flow sensor 30.

  Accordingly, there is an advantage that the influence of the expansion of the inspection target product 200 is small. In other words, in the case of the differential pressure type that compares the pressure drop inside the product to be inspected and the master, when the gas is sent into the product to be inspected, the expansion of the product to be inspected then the pressure drop in the product to be inspected. Affects the behavior of Therefore, it is easy to cause a measurement error. Moreover, since the expansion of the product to be inspected varies from product to product, the inspection accuracy is lowered. According to the present embodiment, even if the product to be inspected expands, it only affects immediately after the expansion. And if the gas of the expansion | swelling volume is exhausted from the airtight container 20, it will become possible to measure only the leak amount with few errors.

  Further, according to the present embodiment, there is an advantage that there is little influence due to the properties of the constituent members of the product to be inspected. That is, in the case of the differential pressure type, the inside of the product to be inspected is stabilized at a predetermined pressure and the amount of leakage is estimated from the degree of pressure drop at the time of sealing thereafter. However, various members exist inside the product to be inspected, and a complicated flow path may be formed. For example, when the product to be inspected is a hollow fiber membrane cartridge, a bundle of hollow fiber membranes and an activated carbon layer are present inside the product, and a complicated and fine flow path is formed. In addition, the constituent members of the product to be inspected may include those that are deformed over time due to gas being pumped. For example, in the case of a hollow fiber membrane cartridge, the hollow fiber membrane, the case, the activated carbon layer, and the like are deformed over time depending on the material. From the above, it may take a considerable amount of time until the compressed gas that has been pumped uniformly reaches the entire interior of the product to be inspected (until the internal pressure is stabilized at a predetermined pressure). On the other hand, according to the present embodiment, although it is necessary to apply a pressure to the inside of the product 200 to be inspected, the presence or absence of leakage can be confirmed if a certain amount of pressure is applied to the inside of the product. Therefore, strictly speaking, there is no need to wait until the inside of the inspection target product 200 is stabilized at a uniform predetermined pressure.

  Further, according to the present embodiment, there is an advantage that there is little influence on the inspection accuracy and the inspection stability due to the size of the inspection target product 200 itself. That is, when the product to be inspected itself is large, in the differential pressure type, as described above, a considerable time is required until the internal pressure of the product to be inspected is stabilized. In addition, if the outer frame (case, etc.) of the inspection target product is large, the inspection target product itself expands when pressure is applied, so that the influence of the pressure drop behavior is increased during leakage measurement. Accordingly, the degree of decrease in inspection accuracy is increased. On the other hand, according to the present embodiment, even if the inspection target product 200 expands, the gas in the volume corresponding to the expansion is exhausted from the airtight container 20 until the pressure in the airtight container 20 is stabilized. The waiting time can be greatly shortened. The waiting time until the pressure stabilizes will be described in more detail. In the case of the differential pressure type, in order to detect the amount of leakage, detection with very high accuracy is required because of the necessity of comparing the difference in pressure drop behavior with the master. Therefore, it is necessary to start measurement after the internal pressure of the product to be inspected is completely stabilized. On the other hand, according to this Embodiment, the gas leaked in the airtight container 20 raises the internal pressure of the airtight container 20, and measures the exhaust amount of the gas accompanying this. In this case, even if the expansion of the inspection target product 200 occurs to a degree that cannot be ignored in the measurement of the exhaust amount, the exhaust flow rate measured at that time is not stable. The amount of leakage can be determined. That is, in the differential pressure type, the measurement of the change with time of the pressure must be started after the expansion (pressure) is completely stabilized. On the other hand, according to the present embodiment, the expansion is stable and relatively fast. The amount of leakage can be determined at each stage.

  Furthermore, according to the present embodiment, there is an advantage that the influence of the environment such as atmospheric pressure, temperature, and humidity is small. That is, if measurement is performed in an environment where the atmospheric pressure, the air temperature, etc. are likely to change, in the case of the differential pressure type, pressure fluctuations due to these are measured, and if the leak is very small, a measurement error will be caused. Further, regarding the humidity, when the constituent member of the product to be inspected is an adsorbent (for example, activated carbon provided in the hollow fiber membrane cartridge), moisture contained in the gas being pumped is adsorbed. Therefore, the pressure drop inside the product is overestimated, and in the case of the differential pressure type, it causes a measurement error. On the other hand, according to the present embodiment, there is no influence from the change in the atmospheric pressure, the temperature, and the humidity as described above.

  If a highly accurate sensor is used as the flow sensor 30, leakage can be detected with high accuracy. As described above, by using the inspection apparatus and the inspection method according to the first embodiment, it is possible to accurately inspect the airtightness of the inspection target product 200.

(Embodiment 2)
The above-described inspection apparatus according to the first embodiment shows the minimum basic configuration, but in practice, in order to perform an appropriate inspection, the inspection target product 200, the airtight container 20, and the flow rate Depending on the quality and performance of the sensor 30, various measures may be required. Therefore, in the present embodiment, an inspection apparatus 100a and an inspection method in which such measures are taken will be described. FIG. 2 is a schematic diagram of an inspection apparatus according to Embodiment 2 of the present invention. Since the basic configuration of the second embodiment is the same as that of the first embodiment, description of the basic configuration is omitted.

<Measures against expansion of products subject to inspection>
When the outer frame (case or the like) of the inspection target product 200 is made of a material having low rigidity such as resin, when the gas is pumped into the product of the inspection target product 200, the outer frame expands. Therefore, the internal pressure in the airtight container 20 (the pressure in the space in the space inside the airtight container 20 excluding the inspection target product 200) increases. That is, since the volume of the space inside the airtight container 20 excluding the inspection target product 200 decreases due to the expansion of the outer frame of the inspection target product 200, the internal pressure in the airtight container 20 increases.

  Thus, gas flows into the exhaust passage T2 by increasing the internal pressure in the airtight container 20. Therefore, while the outer frame of the inspection target product 200 is inflated, the internal pressure in the hermetic container 20 increases because the gas flow rate measured by the flow sensor 30 is due to leakage from the inspection target product 200. It is not possible to determine whether it is caused by doing. Therefore, in order to perform an accurate measurement, it is necessary to wait until the internal pressure in the airtight container 20 is stabilized. In particular, when a flow sensor 30 having a small orifice (throttle) such as a mass flow meter is used, the flow rate of the discharged gas is reduced, so that a considerable time is required until the internal pressure in the hermetic container 20 is stabilized. . Therefore, a countermeasure for such a problem will be described.

  By releasing the internal pressure in the hermetic container 20 for a predetermined period from the start of gas pumping, it is possible to quickly suppress the gas from flowing into the exhaust passage along with the change in the internal pressure in the hermetic container 20. be able to. Specifically, it is a predetermined period after the start of gas pumping (a period in which the internal pressure of the product 200 to be inspected is increased and a few seconds thereafter, the size of the product 200 to be inspected, The gas flows in the exhaust passage along with the change in the internal pressure in the airtight container 20 by releasing the pressure in the airtight container 20 by the relief valve for about 0 seconds to 30 seconds depending on the properties of the constituent members. This can be suppressed early. The relief valve may be directly attached to the main body of the airtight container 20 or may be attached in the middle of the exhaust passage.

  In the present embodiment, an exhaust passage T22 branched from the middle of the exhaust passage T21 reaching the flow sensor 30 is provided, and a relief valve 40 is provided on the exhaust passage T22. Then, the pressure source 10 is controlled to release the pressure in the hermetic container 20 by opening the valve of the relief valve 40 for a predetermined period after the start of gas feeding. FIG. 3 is a timing chart for the operation of the pressure source and the operation of the relief valve. As shown in the figure, simultaneously with turning on the power source of the pressure source 10, the relief valve 40 is turned on to open the relief valve 40. Then, after a predetermined period of time has elapsed, the relief valve 40 is turned off and the relief valve 40 is closed. Thereafter, measurement of the leakage amount is started by the flow sensor 30. Here, during a certain period in which the relief valve 40 is turned on (a certain period in which the valve of the relief valve 40 is opened), as shown in FIG. 3, the pressure inside the product 200 to be inspected is stabilized at a predetermined inspection pressure. After that, it is set so that the period in which the internal pressure of the product 200 to be inspected is rising and the period after the next several seconds have elapsed have elapsed.

As described above, by releasing the pressure in the airtight container 20 by the relief valve 40 for a predetermined period after the start of gas pressure feeding, the gas flows into the exhaust passage along with the pressure change in the airtight container 20. Can be prevented at an early stage. Therefore, the measurement of the amount of gas leakage from the inspection target product 200 can be started early.

<Countermeasures against impact received when gas is sent into the product to be inspected>
When gas is sent into the product of the inspection target product 200 by the pressure source 10, if the pressurized amount of the gas to be pumped is large, depending on the strength of the constituent members of the inspection target product 200, it can withstand the impact of the sent gas. It is thought that it will be damaged without being done. For example, in the case of a water purifier cartridge, a hollow fiber membrane with low strength may be broken without being able to withstand the impact of the gas being fed. Further, if the pressurized amount of the gas to be pumped is large, the expansion of the inspection target product 200 becomes excessively large at the beginning, so that it takes a long time for the expansion volume of the inspection target product 200 to be stabilized. There is also. Therefore, a countermeasure for such a problem will be described.

  When the gas is pumped into the inspection target product 200 by the pressure source 10, the internal pressure of the inspection target product 200 can be prevented from rapidly increasing by adjusting the pressurization amount of the gas to be pumped. . Specifically, the amount of pressurization can be adjusted by providing an electropneumatic regulator 50 as an adjusting means on the pressure feed passage T1. The electropneumatic regulator 50 is a pressure reducing valve that enables pressure adjustment by an electrical signal.

  In this way, when the electropneumatic regulator 50 is provided and the gas is pumped into the product of the inspection target product 200, the pressure applied to the component of the inspection target product 200 is suppressed by gradually increasing the pressure. Can do. Thereby, generation | occurrence | production of the failure | damage etc. of the structural member of the test object product 200 can be prevented. Further, rapid expansion of the inspection target product 200 can be suppressed, and the time until the expansion volume is stabilized can be shortened.

<Measures against measurement errors due to gas leakage from the airtight container itself>
When a gas leak occurs from the airtight container 20 itself, the flow rate sensor 30 cannot accurately measure the gas leak amount from the inspection target product 200. Therefore, it is possible to suppress a measurement error of the amount of gas leakage from the inspection target product 200 by checking whether or not gas leakage has occurred from the airtight container 20 itself in a timely manner.

  Specifically, a three-way valve 60 is provided on the exhaust passage T21. A flow rate sensor 30 is provided on one downstream side of the three-way valve 60 with respect to the airtight container 20, and a differential pressure type airtight inspection machine as an inspection means is provided on the other downstream side through a leak inspection dedicated passage T3 of the airtight container 20. 70 is provided. As the differential pressure type air tightness inspection machine 70, a differential pressure type leak tester or the like can be used.

  With the above-described configuration, when performing the airtightness inspection of the product 200 to be inspected, in the three-way valve 60, the valve on the differential pressure type airtightness inspection machine 70 side is closed and the valve on the flow rate sensor 30 side is opened. When the airtightness inspection of the airtight container 20 itself is performed, in the three-way valve 60, the valve on the differential pressure type airtightness inspection machine 70 side is opened and the valve on the flow rate sensor 30 side is closed. Note that the airtightness inspection of the airtight container 20 itself may be performed in a timely manner according to the reliability of the airtight container 20. Of course, this airtightness inspection may be performed regularly or irregularly. The differential pressure type air tightness inspection machine 70 may use a known technique, and a small amount of leakage that cannot be detected by the differential pressure type air tightness inspection machine 70 usually hardly affects the measurement value by the flow sensor 30.

  As described above, the inspection object caused by the gas leakage from the airtight container 20 itself by inspecting whether the gas leakage from the airtight container 20 itself has occurred in a timely manner by the differential pressure type airtight inspection machine 70 Measurement errors in the amount of gas leakage from the product 200 can be suppressed.

<Countermeasures against impacts received by flow sensors when the amount of gas leakage from the product to be inspected is excessive>
In general, the flow rate sensor 30 used for inspecting leaks of airtight products has a purpose of measuring a minute flow rate, and therefore the measurement range is limited to a narrow range. Therefore, if an excessive flow rate of gas flows, the flow rate sensor 30 may be damaged. In addition, when the airtight container 20 is subjected to a large internal pressure, the seal portion for forming an airtight state may be damaged. Therefore, when the inspection target product 200 is a defective product and has no airtightness, the pressure sensor 30 and the airtight container 20 have a pressure substantially the same as the pressure of the gas fed into the inspection target product 200. It will take. Thereby, there exists a possibility that the seal | sticker part of the flow sensor 30 and the airtight container 20 may be damaged. Therefore, a countermeasure for such a problem will be described.

  The internal pressure of the hermetic container 20 is constantly monitored, and when the internal pressure exceeds a predetermined value, the pressure in the hermetic container 20 is released to prevent the flow sensor 30 and the seal portion of the hermetic container 20 from being damaged. . The predetermined value that is a criterion for releasing the pressure in the hermetic container 20 is set in advance based on the pressure resistance of the flow sensor 30 and the seal portion of the hermetic container 20 so that they are not damaged. can do.

  In the present embodiment, a pressure sensor 80 is provided as detection means for detecting the internal pressure (atmospheric pressure) in the hermetic container 20, and the internal pressure in the hermetic container 20 is constantly monitored. When the value detected by the pressure sensor 80 exceeds a predetermined value, the pressure in the airtight container 20 is released by immediately opening the airtight container 20. Here, as a method of opening the airtight container 20, the airtight container 20 is configured to be moved to a position where an airtight state is formed by an actuator and a position where the inside is opened, and a value detected by the pressure sensor 80 is determined. When the predetermined value is exceeded, the airtight container can be moved by this actuator to open the inside. Moreover, as a method of releasing the internal pressure of the airtight container 20, it is considered possible to provide a one-way valve in the airtight container 20 or the like that opens the valve only when a certain pressure or more is applied.

  By configuring as described above, it is possible to prevent the internal pressure of the airtight container 20 from exceeding a predetermined value. Therefore, it is possible to prevent the seal portion of the flow sensor 30 and the airtight container 20 from being damaged.

(Example)
A more specific embodiment will be described with reference to FIG. FIG. 4 is a schematic configuration diagram of the inspection apparatus according to the embodiment of the present invention. In the present embodiment, a case where the product to be inspected is a hollow fiber membrane cartridge 200a for a water purifier will be described as an example. The hollow fiber membrane cartridge 200a is configured to include a case (airtight case) having an inlet 201 (liquid inlet to be purified) and an outlet 202 (purified liquid outlet). The airtightness of the case is inspected by the inspection apparatus 100b according to the example.

  The airtight container according to the present embodiment includes a bottomed cylindrical container body 20a, a base portion 20b for closing the opening of the container body 20a, and a hollow fiber membrane cartridge 200a to be inspected, and a container A seal ring 22 for sealing between the main body 20a and the base portion 20b is provided.

The container body 20a is configured to move up and down as shown by an arrow X in the figure by an actuator (not shown). Further, joints 20c and 20d are provided on the base portion 20b. And the hollow fiber membrane cartridge 200a is installed in the base part 20b so that the inlet 201 and the outlet 202 may be connected to the joints 20c and 20d, respectively, while the container body 20a is moved upward. When the container body 20a moves to the lowest position, the space between the container body 20a and the base portion 20b is sealed by the seal ring 22, and the space between the inlet 201 and the joint 20c, and between the outlet 202 and the joint 20d are also sealed. The As described above, the hollow fiber membrane cartridge 200a is housed in an airtight container in an airtight state.

  Here, the joint 20c completely seals the inlet 201, whereas the joint 20d has a through hole provided at the center and is connected to the pressure feed passage T1. As a result, gas (air) is sent from the pressure source 10 through the pressure feed passage T1 and the joint 20d into the hollow fiber membrane cartridge 200a from the outlet 202. And since the case with which the hollow fiber membrane cartridge 200a is equipped is sealed by the joint 20c about the inlet 201, only the gas which leaks from the case itself is discharge | released in the airtight container of the test | inspection apparatus 100b. Since the inside of the airtight container is in an airtight state, only the same amount of gas as the amount of gas leaked from the case itself of the hollow fiber membrane cartridge 200a passes through the through hole 21 provided in the base portion 20b, and the exhaust passage T2 It flows to. And the flow volume of the gas which flows through the exhaust passage T2 is measured by the mass flow meter which is the flow sensor 30 provided on this exhaust passage T2. In this way, the amount of gas leakage from the hollow fiber membrane cartridge 200a can be directly measured, and the airtightness of the hollow fiber membrane cartridge 200a can be accurately inspected.

  In this example, various measures described in the second embodiment are provided. That is, as a countermeasure against the expansion of the case of the hollow fiber membrane cartridge 200a, a relief valve 40 for releasing the pressure in the hermetic container is provided for a predetermined period after the start of gas pumping. However, in the second embodiment, the configuration in which the relief valve 40 is provided on the exhaust passage T22 branched from the middle of the exhaust passage T21 in which the flow sensor 30 is provided has been described. However, in this embodiment, the flow sensor 30 is provided. A relief valve 40 is provided on the exhaust passage T2. By exhausting with the relief valve 40, the pressure in the airtight container can be released as in the second embodiment.

  In addition, an electropneumatic apparatus for gradually increasing the pressure of the gas to be fed so that the hollow fiber membrane is not cut by the pressure of the gas to be fed and the case of the hollow fiber membrane cartridge 200a is not rapidly expanded. The regulator 50 is provided on the pressure feed passage T1.

  Further, a differential pressure type air tightness inspection machine 70 for inspecting whether gas leaks from the airtight container itself is also provided. Accordingly, a three-way valve 60 for switching the gas flow is provided to switch between the airtightness inspection of the hollow fiber membrane cartridge 200a and the airtightness inspection of the airtight container itself.

FIG. 1 is a schematic diagram of an inspection apparatus according to Embodiment 1 of the present invention. FIG. 2 is a schematic diagram of an inspection apparatus according to Embodiment 2 of the present invention. FIG. 3 is a timing chart for the operation of the pressure source and the operation of the relief valve. FIG. 4 is a schematic configuration diagram of the inspection apparatus according to the embodiment of the present invention. FIG. 5 is a schematic diagram of an airtight inspection apparatus according to a conventional example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Pressure source 20 Airtight container 20a Container main body 20b Base part 20c, 20d Joint 21 Through-hole 22 Seal ring 30 Flow rate sensor 40 Relief valve 50 Electropneumatic regulator 60 Three-way valve 70 Differential pressure type airtight inspection machine 80 Pressure sensor 100, 100a, 100b Inspection device 200 Product to be inspected 200a Hollow fiber membrane cartridge 201 Inlet 202 Outlet T1 Pressure feed passage T2, T21, T22 Exhaust passage

Claims (8)

In inspection equipment that inspects the airtightness of products,
A pressure-feeding means for sending gas into the product of the product to be inspected;
An airtight container capable of storing a product to be inspected while keeping the inside of the container airtight;
Measuring means for measuring the amount of gas leaking from the product to be inspected by measuring the amount of gas flowing through the exhaust passage connected to the hermetic container when the gas is pumped by the pumping means. Inspection equipment.   2. The inspection apparatus according to claim 1, further comprising a valve that releases pressure in the airtight container for a predetermined period from the start of pumping by the pumping means.   The inspection apparatus according to claim 1, further comprising an adjusting unit that adjusts a pressurizing amount when the gas is pumped into the product by the pumping unit.   The inspection apparatus according to claim 1, 2 or 3, further comprising inspection means for inspecting the amount of gas leakage from the airtight container itself. Detecting means for detecting the atmospheric pressure in the airtight container;
The pressure release means for releasing the pressure in the airtight container when the atmospheric pressure detected by the detection means exceeds a predetermined value, the pressure release means is provided. The inspection device described. In the inspection method for inspecting the airtightness of products,
Storing the product to be inspected in an airtight container in an airtight state;
A process of sending gas into the product to be inspected,
Measuring the amount of gas leaked from the product to be inspected by measuring the amount of gas flowing through the exhaust passage connected to the airtight container while the gas is being sent into the product. Inspection method characterized by that.   The inspection method according to claim 6, further comprising a step of releasing the pressure in the hermetic container for a predetermined period from the start of feeding gas into the product to be inspected.   The inspection method according to claim 6 or 7, wherein when the pressure in the airtight container exceeds a predetermined value during the inspection, the pressure in the airtight container is released.

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