JP2002090252A - Leak tester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a leak tester whose operability can be improved and whose costs can be lowered by a method wherein a connecting tube can be connected to and removed from, the connection port of a specimen without a complicated operation, a connecting implement which connects the connection port of the specimen to the connecting tube can be coupled to, and pulled out from, the connection port when an expansion and contraction body is swollen or returned (contracted) to a normal state and the same connecting implement can be used for specimens having connection ports in different diameters so as to use the connecting implement in common. SOLUTION: The leak tester is provided with a chamber which houses the specimen M at the inside, a tracer-gas supply means which supplies a tracer gas to the specimen M, a tracer-gas detection means which detects the amount of the tracer gas inside the chamber and a connecting tube 40 by which the tracer-gas supply means and the connection port m of the specimen M housed inside the chamber are connected via the connecting implement 44. The connecting implement 44 is constituted to be provided with a stopper substrate 44a comprising a passage 44a1 used to make the inside of the connecting tube 40 communicate with the inside of the specimen M and the expansion and contraction body 44b which is assembled airtightly to the outer circumference of the stopper substrate 44a, in which a gas at a prescribed pressure is sealed at the inside, which can be pulled and inserted with reference to the connection port m in a normal state and which is expanded and coupled airtightly to the connection port m in a state that the circumference is set at a low pressure with reference to the inside.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a leak tester for examining the degree of leakage of an object to be inspected (a gas or liquid contained therein) using a tracer gas (gas for detecting leakage such as helium). About.

[0002]

2. Description of the Related Art As a leak tester of this type, a chamber accommodating an object to be inspected therein, a tracer gas supply means for supplying a tracer gas to the object to be inspected, and a tracer gas detecting an amount of the tracer gas in the chamber A detecting means, and a connection pipe for connecting a connection port of the test object housed in the chamber with the tracer gas supply means via a connector, or the test object is housed therein. A chamber, a tracer gas supply unit for supplying a tracer gas to the chamber, a tracer gas detection unit for detecting a tracer gas amount in the inspection object, and the tracer gas detection unit and the tracer gas contained in the chamber. Some include a connection pipe for connecting a connection port of an inspection object via a connection tool.

In these leak testers, when an object to be inspected is arranged at a predetermined position in a chamber, and a connection pipe is connected to the object to be inspected, for example, a connector provided with a toggle mechanism and having a sealing function is used. By operating the toggle mechanism, it is connected to the connection port of the inspection object.
Then, in the leak test performed thereafter, the inside of the inspection object and the inside of the chamber are evacuated to a predetermined pressure before the supply of the tracer gas, and thereafter, in the former leak tester, Tracer gas is supplied into the inspection object, and the amount of tracer gas leaked into the chamber is detected.
In the latter leak tester, a tracer gas is supplied into the chamber, and the amount of the tracer gas that has entered the inspection object is detected. Further, after the leak test is completed, after the inside of the inspection object and the inside of the chamber are opened to the atmosphere, the above-mentioned toggle mechanism is operated to remove the connection tool from the connection port of the inspection object, thereby connecting the connection pipe to the inspection object. It is designed to be removed from.

[0004]

However, in the above-described conventional leak tester, when connecting the connecting pipe to the object to be inspected and when removing the connecting pipe from the object to be inspected,
As described above, since it is necessary to operate the toggle mechanism to detach and attach the connecting device, there is a problem that workability is poor.
Further, when the diameter of the connection port of the object to be inspected is different, it is necessary to prepare various size fittings corresponding to the size of the diameter, and there is a problem that the cost increases accordingly.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to address the above-described problems, and has a chamber for accommodating an object to be inspected therein, and a tracer gas supply for supplying a tracer gas to the object to be inspected. Means, a tracer gas detection means for detecting a tracer gas amount in the chamber, and a connection pipe for connecting the tracer gas supply means and a connection port of the test object housed in the chamber via a connection tool. In a leak tester comprising: a plug base having a passage for communicating the inside of the connection pipe with the inside of the object to be inspected, the connecting tool is hermetically assembled to the outer periphery of the plug base, and a predetermined pressure is applied inside the plug base. A gas is sealed, and is normally (under atmospheric pressure) detachable from the connection port and hermetically sealed to the connection port by expansion in a state where the pressure is low with respect to the inside. Configuration and the providing the expansion and contraction body case (the invention according to claim 1) is characterized.

Further, the present invention provides a chamber for accommodating an object to be inspected therein, a tracer gas supply means for supplying a tracer gas to the chamber, and a tracer gas detecting means for detecting the amount of tracer gas in the object to be inspected. And a connection pipe connecting the connection port of the test object housed in the chamber via a connection tool, wherein the connection tool is connected to the inside of the connection pipe. A plug base having a passage for communicating the inside of the inspection object, and a gas of a predetermined pressure sealed in the outer periphery of the plug base in an airtight manner, and the connection port is normally (under atmospheric pressure) connected to the connection port. A configuration is provided in which an expansion / contraction body is provided which can be inserted / removed and which hermetically engages with the connection port by expansion in a state where the pressure is low with respect to the inside. It is characterized by bright).

In these cases, it is also possible to provide a supply / discharge passage for supplying / discharging gas into / from the expansion / contraction body in the stopper base (the invention according to claim 3).

[0008]

In the leak tester according to the present invention (the invention according to claims 1 and 2), a connecting tool for connecting the connection pipe to the connection port of the inspection object is provided inside the connection pipe and the inspection object. A plug base having a passage communicating the inside of the plug base, and a gas of a predetermined pressure is hermetically assembled to the outer periphery of the plug base, and a gas of a predetermined pressure is sealed therein. Since the configuration is provided with an expansion / contraction body which is airtightly engaged with the connection port by expansion while the surroundings are at a low pressure with respect to the inside, the test object is arranged in the chamber and the connection port of the test object is provided. When connecting the connecting pipe, if the connecting tool is arranged at a predetermined position of the connecting port, when the inside of the inspection object and the inside of the chamber are evacuated to a predetermined pressure (that is, the periphery of the expansion and contraction body is inside the inside). When the pressure is low). The pressure difference between the inside and outside of the contraction body becomes large, and the expansion and contraction body expands, and airtightly engages with the connection port of the inspection object, thereby connecting the connection pipe to the inspection object in an airtight manner. Can be. After the leak test is completed, when the inside of the test object and the inside of the chamber are opened to the atmosphere, the pressure difference between the inside and outside of the expansion / contraction body becomes small, and the expansion / contraction body returns (shrinks) to the normal state. The connection pipe can be inserted into and removed from the connection port of the object, whereby the connection pipe can be removed from the inspection object.

Therefore, in the leak tester according to the present invention, the connection pipe can be connected to the connection port of the object to be inspected and the connection pipe can be removed from the connection port of the object without requiring complicated operation. , Workability can be improved.

[0010] In the leak tester according to the present invention, a connection tool for connecting the connection port of the inspection object and the connection pipe includes:
As described above, since the expansion and contraction body can be engaged with the connection port and can be removed from the connection port by expansion and return (shrinkage) to the normal state, the same can be applied to an inspection object having a different diameter of the connection port. The connecting device can be used, and the connecting device can be used in common, whereby the cost can be reduced.

Further, when the supply / discharge passage for supplying / discharging gas into / from the expansion / contraction body is provided in the plug base for implementing the present invention (the invention according to claim 3), the connecting tool is provided at a predetermined position of the connection port. Since the gas can be supplied into the expansion / contraction body during the period from the arrangement to the time before the tracer gas is supplied into the inspection object or the chamber, the expansion / contraction body can be expanded. Can be expanded by the pressure difference between the inside and outside and the gas supply pressure, and the airtightness of the connection port and the connection tool can be improved as compared with the first and second aspects of the invention.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of a leak tester according to the present invention. The leak tester includes a chamber 10 for accommodating a test object M therein, and a test object M
Gas supply means 20 for supplying a tracer gas (helium gas for detection) to the apparatus, and a tracer gas detection means 30 for detecting the amount of tracer gas in the chamber 10
And a connection pipe 40 for connecting the tracer gas supply means 20 and the inspection object M.

The chamber 10 has a rectangular parallelepiped shape in which the inspection object M can be accommodated by opening a door (not shown) provided on the front surface, and has five connection ports 11 provided in the chamber 10. , 12, 13, 14, and 15 respectively include a tracer gas supply means 20, a tracer gas detection means 30, an atmosphere opening means 50 of the chamber 10, and a connecting pipe 4.
The vacuum evacuation means 60 of the chamber 10 and the vacuum evacuation means 70 of the chamber 10 are connected.

The tracer gas supply means 20 includes a connecting pipe 4
A tracer gas is supplied to the inspection object M through the nozzle 0, a tracer gas supply cylinder 21, an introduction pipe 22 connected to the cylinder 21 and connected to the connection port 11 of the chamber 10, and It has an interposed on-off valve V1. Further, a pipe 23 connected to the first vacuum pump 25 and a pipe 24 open to the atmosphere are provided at a portion of the introduction pipe 22 closer to the connection port 11 than the open / close valve V1.
Are respectively connected to the pipes 23 and 24, and open / close valves V2 and V3 are interposed in the pipes 23 and 24, respectively.

The tracer gas detecting means 30 includes a tracer gas detector 31 known per se, a pipe 32 connected to the detector 31 and connected to the connection port 12 of the chamber 10, and a pipe 32 interposed therebetween. Open / close valve V4
It has.

As shown in FIG. 2, the connection pipe 40 is a resin inner pipe 41 for introducing a tracer gas into the inspection object M.
And a resin outer tube 42 that covers the inner tube 41 with a predetermined cylindrical space S. One end of the inner tube 41 is connected to the connection port 11 of the chamber 10 in the chamber 10. The connection is made hermetically via a connection tool 43, and the other end is detachably and hermetically connected to a connection port m of the inspection object M via a connection tool 44.

The atmosphere opening means 50 of the chamber 10 is for opening the inside of the chamber 10 by communicating with the atmosphere. One end of the piping 51 is connected to the connection port 13 of the chamber 10, and the other end of the piping 51 is connected to the other end of the piping 51. An on-off valve V5 is provided.

The connecting tube 40 is evacuated by the inner tube 4.
A vacuum is evacuated to a predetermined pressure in the cylindrical space S between the first vacuum pump 1 and the outer pipe 42. The second vacuum pump 61 is connected to the second vacuum pump 61 and connected to the connection port 14 of the chamber 10.
And an on-off valve V6 interposed in the pipe 62.

The evacuation means 70 of the chamber 10 evacuates the interior of the chamber 10 to a predetermined pressure.
A vacuum pump 71 and a pipe 7 connected to the third vacuum pump 71 and connected to the connection port 15 of the chamber 10.
2 and an opening / closing valve V7 interposed in the pipe 72.

The leak tester of the first embodiment configured as described above maintains the vacuum pumps 25, 61, 71 in the operating state, and opens and closes the opening / closing valve V6 intermittently (or continuously). In a state where the cylindrical space S between the tube 41 and the outer tube 42 is evacuated, it is used by repeating the following procedures 1 to 5. With the open / close valves V1 to V7 closed, the chamber 1
0 is opened and the inspection object M is accommodated in the chamber 10,
After connecting the connecting tool 44 assembled to the tip of the connecting pipe 40 to the connecting port m of the inspection object M, the door of the chamber 10 is closed. After the open / close valves V2 and V7 are opened to evacuate the inside of the inspection object M and the chamber 10 to a predetermined pressure, the open / close valves V2 and V7 are closed. Open the open / close valve V1 and open the tracer gas supply cylinder 2
A tracer gas is supplied into the inspection object M from 1 and maintained at a predetermined pressure for a predetermined time. After the elapse of the predetermined time, the open / close valve V4 is opened, and a pass / fail judgment is made by comparing a detection value (leak rate value) detected by the tracer gas detector 31 with a predetermined threshold value. The on-off valves V1 and V4 are closed. The opening and closing valve V3 is opened to discharge the tracer gas in the inspection object M to open the inside of the inspection object M to the atmosphere, and the opening and closing valve V5 is opened to open the inside of the chamber 10 to the atmosphere. Open and take out the inspection object M.

By the way, in the first embodiment,
The connecting tool 44 assembled at the tip of the connecting pipe 40 is
As shown in FIG. 2, a plug base 44a made of metal and a rubber expansion / contraction body 44b hermetically fixed to the outer periphery of the plug base 44a are provided. The plug base 44a is
It has a cylindrical shape, and a passage 44a1 that connects the inside of the inner tube 41 of the connection tube 40 and the inside of the inspection object M is formed in the inside thereof. The expansion / contraction body 44b is provided as shown in FIG.
Are fixed to the plug base 44a at both upper and lower ends by bonding. Further, inside the expansion / contraction body 44b, another gas such as carbon dioxide gas is used in advance as a nitrogen gas of a predetermined pressure (approximately atmospheric pressure) (if it is inert and has low permeability to the expansion / contraction body 44b). The expansion and contraction body 44b can be inserted into and removed from the connection port m under normal conditions (at atmospheric pressure), and expanded and contracted into the connection port m with the surroundings at a low pressure. It is designed to engage airtightly.

For this reason, in the above procedure, the connecting device 4
By arranging 4 at a predetermined position of the connection port m of the inspection object M, when the inside of the inspection object M and the inside of the chamber 10 are evacuated to a predetermined pressure in the above procedure (that is, the expansion and contraction body 44b is closed). When the surroundings are at a low pressure relative to the inside), the pressure difference between the inside and outside of the expansion and contraction body 44b increases, and the expansion and contraction body 44b expands (see the phantom line in FIG. The connection pipe 40 can be connected to the inspection object M by airtight engagement with the opening m. Further, in the above procedure, when the inside of the inspection object M and the inside of the chamber 10 are opened to the atmosphere, the pressure difference between the inside and outside of the expansion / contraction body 44b becomes small, and the expansion / contraction body 44b returns (shrinks) to the normal state (FIG. 2), and can be inserted into and removed from the connection port m of the inspection object M, whereby the connection pipe 40 can be removed from the inspection object M.

Therefore, in the leak tester according to the first embodiment, the connection pipe 40 can be connected to the connection port m of the inspection object M without performing a complicated operation, and the connection port m of the inspection object M can be connected. The connection pipe 40 can be removed, and workability can be improved.

Further, in the leak tester according to the first embodiment, as described above, the connector 44 for connecting the connection port m of the inspection object M and the connection pipe 40 is used to expand and contract the expansion / contraction body 44b. Since it can be engaged with the connection port m and can be inserted / removed from the connection port m by the return (shrinkage), the same connection tool 44 can be used for a test object having a different diameter of the connection port. Can be shared, thereby reducing costs.

In the first embodiment, the connector 44
A gas such as nitrogen gas is previously sealed in the expansion / contraction body 44b, and the expansion / contraction body 44b expands / contracts due to a pressure difference between the inside and the outside of the expansion / contraction body 44b.
4 is connected to the connection port m and removed, but the connection tool may be configured and implemented as in the modified embodiment shown in FIG.

In the connector 144 of this modified embodiment, a supply / discharge passage 144a2 for supplying / discharging nitrogen gas into / from the expansion / contraction body 144b is provided in the plug base 144a. One end of the supply / discharge passage 144a2 opens toward the inside of the expansion / contraction body 144b, and the other end opens toward the inside of a resin gas supply / discharge pipe 145 attached to the plug base 144a. The gas supply / discharge pipe 145 is provided with an opening / closing valve (not shown) and connected to a nitrogen gas supply / discharge means (not shown). By opening and closing, the expansion / contraction body 14
4b while supplying nitrogen gas into the expansion and contraction body 14b.
Nitrogen gas is discharged from inside 4b. The gas supplied and discharged into the expansion / contraction body 114b is not limited to nitrogen gas, but may be, for example, carbon dioxide gas as long as it is inert and has low permeability to the gas supply / discharge pipe 145. good.

Therefore, in this modified embodiment, it is possible to expand the expansion / contraction body 144b by supplying nitrogen gas into the expansion / contraction body 144b. It can be expanded by pressure, and the airtightness of the connection port m and the connection tool 144 can be improved as compared with the first embodiment.

In the first embodiment and its modified embodiments, the present invention relates to a leak tester of the type in which a tracer gas is supplied to the inspection object M and the amount of the tracer gas leaking into the chamber 10 is detected. However, the present invention is applied to a leak tester of a type that supplies a tracer gas to the chamber 10 and detects the amount of tracer gas leaking into the inspection object M as in the second embodiment shown in FIG. Can also be implemented.

The leak tester of the second embodiment shown in FIG. 4 (an effective embodiment in which the tracer gas usage is small when the residual volume in the chamber 10 is smaller than the volume in the inspection object M) is used. A configuration in which the tracer gas detection means 30 is connected to the connection port 11 of the chamber 10 and the inspection object M and the tracer gas detection means 30 are connected by the connection pipe 40, and the tracer gas supply means 20 is provided in the connection port 12 of the chamber 10 Since the configuration is substantially the same as that of the first embodiment except for the configuration in which the tracer gas is supplied from the tracer gas supply means 20 into the chamber 10 from the connection, the same reference numerals are used for the same components. The detailed description is omitted. The pipes 23 and 24 are connected to a portion of the pipe 32 closer to the connection port 11 than the on-off valve V4.

By the way, also in the second embodiment,
Since the configuration of the connection tool 44 is the same as that of the first embodiment, the same operation and effect as those of the first embodiment can be obtained.

[Brief description of the drawings]

FIG. 1 is a front view schematically showing a first embodiment of a leak tester according to the present invention.

FIG. 2 is a longitudinal sectional front view schematically showing the connecting tool shown in FIG. 1;

FIG. 3 is a longitudinal sectional front view showing a modified embodiment of the connecting device shown in FIG. 2;

FIG. 4 is a front view schematically showing a second embodiment of a leak tester according to the present invention.

[Explanation of symbols]

10: chamber, 20: tracer gas supply means, 30
... tracer gas detecting means, 40 ... connecting pipe, 44 ... connector, 44a ... plug base, 44a2 ... supply / discharge passage, 44b ... expansion / contraction body, M ... test object, m ... connection port of test object.

Claims (3)

[Claims] A chamber accommodating an inspection object therein;
A tracer gas supply unit that supplies a tracer gas to the inspection object, a tracer gas detection unit that detects a tracer gas amount in the chamber, and the tracer gas supply unit and the inspection object housed in the chamber. In a leak tester provided with a connection pipe for connecting a connection port via a connection tool, a plug base having a passage for communicating the connection tool with the inside of the connection pipe and the inside of the object to be inspected; A gas of a predetermined pressure is sealed in the outer periphery and gas is sealed in the inside, and the gas is airtightly sealed to the connection port by expansion in a state where the gas can be pulled in and out of the connection port under normal conditions and the surroundings are at a low pressure with respect to the inside. A leak tester characterized by comprising an inflating / contracting body that engages with a leak tester. A chamber accommodating an object to be inspected therein;
A tracer gas supply unit that supplies a tracer gas to the chamber, a tracer gas detection unit that detects a tracer gas amount in the inspection object, and a tracer gas detection unit that detects the amount of the tracer gas in the inspection object. In a leak tester provided with a connection pipe for connecting a connection port via a connection tool, a plug base having a passage for communicating the connection tool with the inside of the connection pipe and the inside of the object to be inspected; A gas of a predetermined pressure is sealed in the outer periphery and gas is sealed in the inside, and the gas is airtightly sealed to the connection port by expansion in a state where the gas can be pulled in and out of the connection port under normal conditions and the surroundings are at a low pressure with respect to the inside. A leak tester characterized by comprising an inflating / contracting body that engages with a leak tester. 3. The leak tester according to claim 1, wherein a supply / discharge passage for supplying / discharging gas to / from the expansion / contraction body is provided in the plug base.