JP2013019867A - Gas type leakage inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To determine whether or not there is a leakage point in a workpiece in a short time and with high accuracy.SOLUTION: Inspection gas is introduced to a hollow chamber 24 after gas is exhausted from the hollow chamber 24 of a case member 18 (workpiece). Gas in a monitor space 69 is agitated preferably under operation of a first fan 94 and a second fan 110 and then sent to a circulating piping 116. When the gas reaches a detector 122, a display value of the detector 122 represents a value according to concentration (amount) of leakage gas. If there is a leakage point in the case member 18, the inspection gas is leaked to a chamber 16 and mixed with the gas in the monitor space 69. The mixed gas is partially sent to the detector 122 through the circulating piping 116 and a sampling line 121. Meanwhile, the rest of the mixed gas is returned to the monitor space 69 through the circulating piping 116.

Description

  The present invention relates to a gas-type leak inspection apparatus for inspecting whether or not there is a leak location where airtightness cannot be ensured in a wall portion of a workpiece.

  For example, some casting products and forging products are used as a storage container for storing a liquid such as oil or a pressure container for storing a fluid having a pressure higher than atmospheric pressure. In such an application, it is necessary that the content does not leak, in other words, it is excellent in airtightness.

  However, there may be a leaked portion in the cast product or the forged product. For example, in a cast product, there is a possibility that a leakage point may be formed due to a casting defect. For this reason, it is widely performed to check whether or not there is a leaked part for a cast product or a forged product. As an inspection apparatus for performing such confirmation, a gas leak inspection apparatus is well known.

  In this case, first, a work (a cast product or a forged product) is accommodated in a chamber, and the inside of the chamber and a hollow portion of the work are evacuated to a vacuum state. Next, the inspection gas is introduced into the hollow portion of the workpiece. After that, if a predetermined amount or more of the inspection gas does not leak into the chamber when a certain time has elapsed, it is considered as a passing product with sufficient airtightness secured, and the inspection gas of a predetermined amount or more If it leaks inside, it is considered as a rejected product with insufficient airtightness.

  The type of inspection gas used varies depending on the inspection content (application), but helium is mainly used. In this case, it is possible to detect that there is a leak even when the leak amount is very small. That is, there is an advantage that the leakage inspection result can be obtained with high accuracy.

  In this type of gas leakage inspection apparatus, an exhaust unit for evacuating the chamber and an exhaust unit for evacuating the hollow portion of the work are necessary, and the exhaust system becomes large. Moreover, the sealing property of the measuring device for measuring the leakage amount is also important, so that the device configuration becomes complicated and the initial capital investment becomes high. In addition, problems such as not easy maintenance, low availability, and high running costs are becoming apparent.

  From this point of view, Patent Documents 1 and 2 propose that a leakage inspection is performed with the inside of the chamber at atmospheric pressure while the hollow portion of the workpiece is evacuated to a vacuum state. According to Patent Documents 1 and 2, the configuration of the apparatus can be simplified to the extent that an exhaust means for evacuating the chamber is unnecessary.

JP-A-6-221950 JP-A-6-347362

  In the gas leakage inspection method described in Patent Document 1, a preliminary inspection (differential pressure leakage inspection) is performed on a workpiece, and then the main inspection using helium gas is performed. That is, a two-stage inspection is performed. In addition, when the gas leakage inspection method described in Patent Literatures 1 and 2 is implemented, it is possible to determine whether or not the leakage occurs only within the detection accuracy range of the sensor that detects the inspection gas in any of the inspection methods. .

  Further, the gas leakage inspection methods described in Patent Documents 1 and 2 have a problem that it takes a long time to obtain a reliable inspection result.

  The present invention has been made to solve the above-described problem, and it is possible to judge the leakage state accurately and quantitatively the scale of the leakage, and in addition, the gas type leakage inspection having excellent versatility. An object is to provide an apparatus.

In order to achieve the above object, the present invention is a gas leakage inspection apparatus for inspecting whether there is leakage from a wall portion of a workpiece,
The base,
A mounting table provided on the base for positioning and fixing the workpiece;
A clamping board for clamping the workpiece together with the mounting table;
A sandwiching plate displacement mechanism that is supported by the base and displaces the sandwiching plate toward or away from the workpiece;
A partition member that forms a chamber that approaches or separates from the mounting table and surrounds the workpiece when contacting the mounting table;
A partition member displacement mechanism supported by the base for displacing the partition member in a direction approaching or separating from the mounting table;
Exhaust means for exhausting air from a hollow chamber formed by the wall portion of the workpiece;
Inspection gas supply means for supplying inspection gas to the hollow chamber;
Sampling gas discharged from a monitor space defined between the holding plate that is in contact with the workpiece in the chamber and the partition member that is in contact with the mounting table and forms the chamber is the monitor space. A circulation flow path to return to
Inspection gas detection means for supplying the sampling gas via the circulation flow path;
With
When the sampling gas contains the inspection gas, the inspection gas detection means detects the inspection gas.

  That is, in the present invention, when the leak inspection is performed, the gas discharged from the monitor space is returned to the monitor space via the circulation passage.

  When the sampling gas discharged from the chamber is guided to the detection means as in the prior art and then the sampling gas is exhausted out of the system as it is, the degree of leakage of the inspection gas from the hollow chamber of the workpiece to the chamber is reduced. If it is small, the amount of leaky inspection gas present in the chamber is also small. Therefore, the amount of leakage inspection gas contained in the sampling gas is extremely small. It is difficult to accurately evaluate the amount of leakage inspection gas using such a sampling gas.

  On the other hand, in this invention, the gas discharged | emitted from the monitor space is returned to the monitor space via the circulation flow path. That is, the gas is circulated. For this reason, since the leakage inspection gas is sequentially accumulated in the monitor space, the sampling gas containing the leakage inspection gas having a concentration corresponding to the leakage amount is sent to the inspection gas detection means. Therefore, it is possible to measure the amount of leakage inspection gas with high accuracy.

  Moreover, even if the amount of leakage is very small, the measurement result can be obtained quickly. In other words, the amount of leakage can be measured in real time.

  As described above, according to the present invention, it is possible to evaluate the amount of leakage inspection gas in a short time and with high accuracy.

  When the work has a through-hole formed on the side thereof, a closing member for closing the through-hole may be provided. The blocking member may be attached to and detached from the through hole manually by the operator, but may be automatically attachable and detachable. In the latter case, the clamping plate may be provided with closing member displacing means for displacing the closing member in a direction to seal or open the through hole.

  Here, for example, when it is found that there is a leaking part in the workpiece, it may be investigated where the leaking part is. In this investigation, it is necessary to raise the partition member to open the chamber and expose the workpiece.

  If the partition member is provided with the closure member displacement means, the work piece is exposed by raising the partition member unless the closure member displacement means is urged to remove the closure member from the side through-hole. I can't. In this case, since the exposed through hole of the exposed work is open to the atmosphere, a large amount of inspection gas is led to the atmosphere through the through hole. Under such circumstances, it is difficult to identify the leak location.

  On the other hand, when the closing member displacing means is provided on the sandwiching plate, the partition wall member can be lifted while being sandwiched between the mounting table and the sandwiching plate and the side through-hole is closed by the closing member. That is, the work in a state where the inspection gas is introduced into the hollow chamber is exposed. Therefore, it is possible to identify the leakage location by investigating where the inspection gas is leaking from this work.

  In addition, it is preferable to provide a sealing member in the site | part which contact | abuts the said workpiece | work of at least any one of the mounting base or the said clamping board. Since the seal member seals between the workpiece and the mounting table or the sandwiching plate, it is possible to prevent the inspection gas from leaking into the monitor space from between the workpiece and the mounting table or the sandwiching plate. Therefore, since it is possible to prevent the inspection gas from leaking to the monitor space from other than the leaked portion, whether or not there is the test gas leaked to the monitor space through the leaked portion, and if so, to what extent Can be evaluated with higher accuracy.

  In addition, it is preferable to further provide a plurality of support members whose height direction dimensions are the same as the height direction dimensions of the workpiece. In this case, when the workpiece is clamped between the mounting table and the clamping board, the support member supports the clamping board. For this reason, the reaction force acting on the sandwiching plate is dispersed, and as a result, it is avoided that the sandwiching plate warps and a gap is formed between the sandwiching plate and the workpiece. The seal between is maintained.

  When a light gas such as helium is used as the inspection gas, when the inspection gas leaks into the monitor space due to the presence of a leak in the workpiece, the leaked inspection gas stays near the ceiling of the monitor space It is easy to (localize). When such a situation occurs, the concentration of the leakage inspection gas varies depending on the sampling location. Therefore, it is not easy to accurately evaluate the concentration and thus the amount of the leakage inspection gas.

  Therefore, it is preferable to provide a plurality of stirring means for stirring the gas in the monitor space. Along with this stirring, a flow occurs in the gas in the monitor space. As a result, it is avoided that the leakage inspection gas is localized and diffuses almost uniformly in the monitor space. Therefore, the concentration of the leakage inspection gas is substantially the same regardless of the position in the monitor space. For this reason, it is possible to evaluate the amount of the leakage inspection gas with high accuracy regardless of the sampling location.

  At least one of the stirring means can be provided, for example, on the holding plate. In this case, a flow along the vertical direction is formed in the gas in the monitor space.

  Alternatively, at least one of the stirring means may be provided on the side wall of the chamber to form a flow along the horizontal direction in the gas in the monitor space. Of course, in addition to this flow, a flow along the vertical direction described above may be formed.

  Moreover, it is preferable to arrange | position a core in a hollow chamber. This core reduces the space volume of the hollow chamber. Accordingly, the amount of gas exhausted from the hollow chamber and the amount of inspection gas introduced into the hollow chamber are reduced, so that the tact time of the leakage inspection can be shortened accordingly.

  Furthermore, it is preferable to curve the inner corner of the partition member. As described above, when a light gas is used as the inspection gas, the leaky inspection gas is likely to be localized near the ceiling portion of the monitor space, but this tendency becomes remarkable when the corner is angular. However, when the corner portion is a curved portion, the gas easily flows along the curved portion. This also contributes to preventing the leakage inspection gas from being localized in the monitor space.

  In any case, it is preferable that a mounting table displacement means for displacing the mounting table is provided on the base. In this case, the workpiece can be placed on the mounting table in a state where the mounting table is pulled out. In other words, it is possible to perform the mounting operation at a position separated from the partition member, the partition member displacement means, the sandwiching board, the sandwiching board displacement means, and the like. Therefore, these members and means do not get in the way. In particular, when the placement operation is performed by a robot, the robot arm is prevented from interfering with these members and means, thereby facilitating teaching.

  According to the present invention, when performing a leakage inspection, only a part of the gas sampled from the monitor space is used for the inspection in order to inspect whether or not the workpiece has a leakage, and the remaining part is passed through the circulation flow passage. To return to the monitor space. For this reason, the leaked inspection gas is sequentially accumulated in the monitor space, and becomes a high concentration and is sent to the inspection gas detection means. Accordingly, it is possible to evaluate the amount of the leakage inspection gas with high accuracy in a short time.

1 is an overall schematic front view schematically showing a gas leakage inspection apparatus according to an embodiment of the present invention. It is a principal part schematic side view of the gas type leak test | inspection apparatus of FIG. It is a top view of the mounting base which comprises the gas type leak test | inspection apparatus of FIG. It is a principal part enlarged view of FIG. It is a top view from the lower part of the sealing member which comprises the clamping board with which the gas-type leak test | inspection apparatus of FIG. 1 comprises.

  Hereinafter, preferred embodiments of the gas type leak inspection apparatus according to the present invention will be described in detail with reference to the accompanying drawings. In the present embodiment, it is assumed that leakage inspection is performed on a case member before being assembled as a mission component.

  FIG. 1 is an overall schematic front view schematically showing a gas leakage inspection apparatus 10 according to the present embodiment. This gas leakage inspection apparatus 10 has a chamber 16 formed by a mounting table 12 and a partition member 14, and a case member 18 as a workpiece is accommodated in the chamber 16.

  Here, as is well known, the mission component is configured by connecting a plurality of case members to each other, and has an internal space for accommodating a transmission and lubricating oil. On the bottom wall of the case member 18, for example, an opening 20 for connecting another case member is formed. Further, as described in JP-A-2005-181207, the bottom wall, the side wall, and the ceiling wall are provided with a lubricating oil pressure detection hole, a driven pulley oil pressure detection hole, a reverse brake oil pressure detection hole, and a forward clutch oil pressure detection. A hole, a drive pulley hydraulic pressure detection hole and the like are formed through. Hereinafter, these holes are not particularly distinguished, and the through hole formed in the bottom wall, the through hole formed in the side wall, and the through hole formed in the ceiling wall are respectively referred to as “bottom wall through hole” and “side wall through”. The reference numerals of the side wall through hole and the ceiling wall through hole are designated as 21 and 22, respectively. The bottom wall through hole is not shown.

  The case member 18 has a hollow chamber 24 for forming the internal space when assembled as a mission component. The gas-type leak inspection apparatus 10 detects when a test gas leaks from the hollow chamber 24 of the case member 18 through the bottom wall, side wall, or ceiling wall.

  As shown in FIG. 2, the gas leak inspection apparatus 10 has a base 26 installed on the floor of a work station. The base 26 includes a first support base 28, a second support base 30, and a third support base 32 (see FIG. 1), and the first support base 28 includes a first support base 28 as a mounting base displacement means. One cylinder 34 (see FIG. 2) is supported. The first rod 36 constituting the first cylinder 34 is connected via a connecting bracket 38 to the lower end surface of the mounting table 12 provided on the second support table 30 so as to be displaceable.

  As schematically shown in FIG. 2, two guide rails 40 a and 40 b are provided on the upper end surface of the second support base 30 so as to extend in parallel with each other. A slider 42 is slidably engaged with each of the guide rails 40 a and 40 b, and the mounting table 12 is bridged by the slider 42. Therefore, the mounting table 12 is displaced along the extending direction of the guide rails 40a and 40b together with the slider 42 as the first rod 36 moves forward or backward.

  A first annular groove 44 having a shape corresponding to the shape of the opening 20 formed in the bottom wall of the case member 18 is formed on the upper end surface of the mounting table 12 as shown in FIG. . The first annular groove 44 accommodates a first seal member 46 for preventing the inspection gas introduced into the hollow chamber 24 from leaking from the opening 20. In addition, a plurality of plugs 48 for closing the bottom wall through-hole are provided on the upper end surface of the mounting table 12, and a plurality of stoppers 50 for damming and fixing the case member 18 can be removed. Is provided. Accordingly, the case member 18 is positioned and fixed by blocking the side wall of the case member 18 by the stopper 50.

  As shown in FIG. 4 which is a schematic diagram of the main part of FIG. (See FIG. 1). When the case member 18 is positioned and fixed on the mounting table 12, the hollow chamber 24 of the case member 18 is in a position communicating with the exhaust hole 52, the inspection gas introduction hole 54, and the inspection gas recovery hole 55.

  A core 56 is accommodated in the hollow chamber 24. The presence of the core 56 reduces the space volume of the hollow chamber 24. Therefore, the amount of gas to be exhausted from the hollow chamber 24 and the amount of inspection gas introduced into the hollow chamber 24 can be reduced.

  The core 56 has a size that can be accommodated in the hollow chamber 24, and is not particularly limited as long as it is an object that does not absorb or absorb the inspection gas, but a bulk body such as an iron lump is preferable. An example.

  A first exhaust pipe 60 to which a first clean pump 58 is connected is inserted into the exhaust hole 52. Further, a test gas introduction pipe 62 and a test gas recovery pipe 63, which are individually connected to a test gas supply means (not shown), are inserted into the test gas introduction hole 54 and the test gas recovery hole 55, respectively.

  As the inspection gas, helium, hydrogen, argon, etc. that are generally used in gas type leak inspection may be adopted. However, when it is required to detect a very small amount of leakage, in other words, high Helium is preferable for detection with high accuracy. Argon has a large diameter, and it is not easy to leak from a fine crack (ie, it is not easy to detect the presence of a fine crack), whereas helium has a small diameter, so it is difficult to leak. This is because it is possible to detect the presence of the crack. Moreover, as will be described later, helium used for the inspection can be recovered and reused. An example of a means that can supply helium is a cylinder.

  A reference gas introduction hole 64 is also formed through the mounting table 12 along the thickness direction. The reference gas introduction hole 64 is formed at a position that does not communicate with the hollow chamber 24 of the case member 18 but communicates with the chamber 16. A reference gas supply means (not shown) is connected to one end of the reference gas introduction pipe 66 inserted into the reference gas introduction hole 64, and a leak master 68 is connected to the remaining one end facing the hollow chamber 24. The leak master 68 is disposed above the mounting table 12 and is accommodated in the chamber 16 together with the case member 18.

  The leak master 68 is adjusted so that the reference gas is discharged into the chamber 16 with a predetermined leak amount.

  The reference gas supply means is for supplying a reference gas to a monitor space 69 (described later) via a reference gas introduction pipe 66 and a chamber 16, and a specific example thereof is a cylinder. The reference gas is the same gas as the inspection gas. That is, when helium is used as the inspection gas, the reference gas is also helium.

  A second exhaust pipe 70 is branched from the reference gas introduction pipe 66. The second exhaust pipe 70 joins the first exhaust pipe 60 and is connected to the first clean pump 58. A pressure sensor 71 is provided in this connection line.

  In the above configuration, the first exhaust pipe 60, the inspection gas introduction pipe 62, the reference gas introduction pipe 66, and the second exhaust pipe 70 include the first valve 72, the second valve 74, the third valve 76, and the like. Each of the fourth valves 78 is interposed. Similarly, a fifth valve 79 is provided in the inspection gas recovery pipe 63.

  Four support columns 80 a to 80 d (support members) are further provided on the upper end surface of the mounting table 12 so as to surround the case member 18.

  As the support columns 80a to 80d, those having different height direction dimensions are prepared in advance, and one having the same dimension as the height direction dimension of the case member 18 to be inspected for leakage is placed on the mounting table 12. It is attached. That is, after performing a leak test on an arbitrary case member 18, when performing a leak test on another case member having a height dimension different from that of the case member 18, the columns 80 a to 80 d are placed on the mounting table 12. After being removed from the mounting column 12, the columns 80 a to 80 d having the same dimensions as the height of the other case member are attached to the mounting table 12.

  The case member 18 is sandwiched between the mounting table 12 configured as described above and the sandwiching plate 82 in the chamber 16. The sandwiching plate 82 includes a sealing member 84 that comes into contact with the case member 18, and a support plate 86 that has the sealing member 84 attached to the lower end surface and that is wider than the sealing member 84.

  Among these, the lower end surface of the sealing member 84 facing the case member 18 corresponds to the shape of the relatively large-diameter ceiling wall through hole 22 formed in the ceiling wall of the case member 18 as shown in FIG. A second annular groove 88 having a shape is formed. The second annular groove 88 accommodates a second seal member 90 for preventing the inspection gas from leaking from the ceiling wall through hole 22. In addition, a plurality of plugs 92 for closing the small-diameter ceiling wall through hole 22 are provided on this end surface.

  As shown in FIG. 1, first fans 94 (stirring means) are respectively provided at the corners in the width direction of one support plate 86. These first fans 94 are for agitating the gas in the chamber 16, particularly in the monitor space 69. Each first fan 94 faces in the vertical direction, and therefore the first fan 94 causes convection along the vertical direction to the gas in the monitor space 69. That is, the gas in the monitor space 69 repeatedly rises and falls in the monitor space 69 under the action of the first fan 94.

  The support board 86 is provided with a plurality of brackets 96 at positions different from the first fan 94. Each bracket 96 supports a second cylinder 98 (closing member displacing means).

  A closing member 102 is provided at a position corresponding to the position of the side wall through hole 21 of the case member 18 at the tip of the second rod 100 constituting the second cylinder 98. Of course, the closing member 102 enters the side wall through hole 21 when the second rod 100 moves forward, closes the side wall through hole 21, and leaves the side wall through hole 21 when the second rod 100 moves backward.

  A third rod 106 constituting a third cylinder 104 (clamping disk displacement mechanism) is connected to the upper end surface of the support board 86. The third rod 106 is moved forward (down) or moved backward (lifted), and the holding plate 82 is displaced in a direction approaching or separating from the case member 18.

  A third seal member 108 is attached to the bottom surface of the partition member 14 constituting the chamber 16. The third seal member 108 seals between the mounting table 12 and the partition member 14.

  The gas present in the space defined between the support plate 86 and the ceiling wall of the partition wall member 14 is led out of the chamber 16 as a sampling gas. The monitor space 69 refers to the space where the sampling gas is obtained, and the same applies to the following.

  Further, a second fan 110 serving as a stirring unit is provided above the left side surface and below the right side surface of the partition member 14. Each second fan 110 faces in the horizontal direction, and therefore the second fan 110 causes convection along the horizontal direction to the gas in the monitor space 69. In other words, in the monitor space 69, a flow that repeatedly rises and falls occurs under the action of the first fan 94, while the flow moves from the left to the right or in the opposite direction under the action of the second fan 110. Occurs.

  A first circulation hole 112 and a second circulation hole 114 are formed above the left side surface of the partition wall member 14, and each of the first circulation hole 112 and the second circulation hole 114 is shown in FIG. As described above, the forward piping 118 and the backward piping 120 that constitute the circulation piping 116 (circulation flow passage) are inserted. In the present embodiment, the path from the first circulation hole 112 to the sampling line 121 is defined as the forward piping 118 and the path from the sampling line 121 to the second circulation hole 114 is defined as the return piping 120. Here, the sampling line 121 is provided so as to branch from the circulation pipe 116.

  The sampling line 121 is connected to the inlet connection joint of the detector 122 as a leakage inspection gas detection means. In addition, an intake pump 123 and a first electromagnetic valve 124 are interposed in the forward piping 118, and either the forward piping 118 or the probe piping 126 is associated with the switching of the first electromagnetic valve 124 therein. It is selectively opened or closed. As a result, either the gas in the forward piping 118 or the gas in the probe piping 126 is selectively guided to the detector 122.

  A sampling gas discharge pipe 129 is connected to the outlet connection joint of the detector 122.

  On the other hand, a second solenoid valve 130 is interposed in the return pipe 120. As the second electromagnetic valve 130 is switched, either the return pipe 120 or the line cleaning pipe 132 is selectively opened or closed. As a result, the gas in the return pipe 120 is selectively guided to either the monitor space 69 or the second clean pump 134 connected to the line cleaning pipe 132.

  Further, a cleaning hole 136 is formed through the right side surface of the partition wall member 14 so as to penetrate therethrough. The cleaning hole 136 is connected to a chamber cleaning pipe 140 in which a two-way valve 138 is interposed. The chamber cleaning pipe 140 and the outlet pipe 142 connected to the first clean pump 58 are connected to the second clean pump 134. That is, to the second clean pump 134, a line cleaning pipe 132, a chamber cleaning pipe 140, and an outlet pipe 142 are connected.

  A curved portion 144 is formed at the boundary between the side wall and the ceiling wall of the partition wall member 14. In other words, the inner corner of the partition member 14 is curved.

  Further, an insertion hole 146 is formed through the ceiling wall of the partition wall member 14. The third rod 106 is connected to the upper end surface of the support board 86 through the insertion hole 146. Of course, the space between the inner wall of the insertion hole 146 and the side wall of the third rod 106 is sealed by a seal member (not shown).

  A fourth rod 150 constituting a fourth cylinder 148 (partition member displacement mechanism) is coupled to the outer upper end surface of the ceiling wall. The partition member 14 is displaced in a direction in which the fourth rod 150 moves forward (down) or backward (up) and approaches or separates from the mounting table 12. Of course, the fourth rods 150 are lowered or raised in synchronization with each other.

  In the above configuration, the third cylinder 104 and the fourth cylinder 148 are supported by the third support base 32 of the base 26 (see FIG. 2). Further, the pressure sensor 71 and the detector 122 are electrically connected to the control circuit 156 via signal lines 152 and 154, respectively.

  The gas-type leak inspection apparatus 10 according to the present embodiment is basically configured as described above, and next, its operation and effect will be described in relation to the calibration method and the leak inspection method.

  First, a pre-calibrated leak master 68 is attached. That is, for example, when the leak master 68 is set to derive the inspection gas at 0.5 cc / min, it is possible to derive the inspection gas at 0.5 cc / min almost accurately.

  Further, the detector 122 is also calibrated. For this purpose, for example, a pipe (not shown) branched from the reference gas introduction pipe 66 and connected to the detector 122 may be provided to introduce the reference gas into the detector 122.

  And the 1st cylinder 34 is urged | biased and the 1st rod 36 is advanced. Following this, the mounting table 12 connected to the first rod 36 via the connecting bracket 38 is pulled out of the second support table 30 and protrudes while being guided by the guide rails 40a and 40b. Of course, in this case, the slider 42 slides on the guide rails 40a and 40b.

  Next, the core 56 is mounted on the mounting table 12. The core 56 is not particularly required to be positioned and fixed, but it is needless to say that the core 56 may be positioned and fixed.

  Thereafter, the case member 18 that has been confirmed in advance to prevent leakage is placed on the mounting table 12. Along with this placement, the core 56 placed in advance on the placement table 12 is accommodated in the hollow chamber 24 of the case member 18.

  Since the mounting table 12 is pulled out in front of the second support table 30, the case member 18 is prevented from interfering with the partition wall member 14, the base 26, and the like, so that the case member 18 can be easily attached to the mounting table 12. Can be placed. In particular, when the case member 18 is mounted on the mounting table 12 by a robot, the robot arm is prevented from interfering with the partition wall member 14 or the base 26. For this reason, teaching to the robot becomes easy.

  When the case member 18 is placed on the mounting table 12, the first seal member 46 (see FIG. 3) contacts the bottom wall near the opening 20 formed in the case member 18, and the case member 18 penetrates the bottom wall. Plug 48 enters the hole. The bottom wall through hole is finally closed by the plug 48. In combination with this, the side wall of the case member 18 is blocked by the stopper 50, and the case member 18 is positioned and fixed to the mounting table 12.

  Next, the first cylinder 34 (see FIG. 2) is re-biased, and the first rod 36 is moved backward. As a result, the mounting table 12 returns to the second support table 30 while being guided by the guide rails 40 a and 40 b and is stored in the base table 26. As a result, the case member 18 is positioned to face the partition wall member 14.

  Next, the third cylinder 104 is energized and the third rod 106 is lowered. Accordingly, the sealing member 84 of the sandwiching plate 82 lowered is seated on the ceiling wall of the case member 18 and the upper end surfaces of the four columns 80a to 80d. Since the height direction dimensions of the support columns 80a to 80d are the same as the height direction dimension of the case member 18, the sealing member 84 is provided on the ceiling wall of the case member 18 and the upper end surfaces of the four support columns 80a to 80d. It abuts at the same time.

  By this contact, the support member constituting the sandwiching plate 82 is supported from the columns 80a to 80d. For this reason, the reaction force acting on the sandwiching plate 82 is dispersed, so that the sandwiching plate 82 is prevented from warping. As a result, the formation of a gap between the ceiling wall of the case member 18 and the sealing member 84 is avoided, and the seal between the two members is maintained.

  When the sealing member 84 is seated on the case member 18, the second sealing member 90 (see FIG. 5) contacts the ceiling wall near the large-diameter ceiling wall through hole 22 formed in the case member 18, and the case member 18 The plug 92 enters the small-diameter ceiling wall through hole 22. That is, the small-diameter ceiling wall through hole 22 is closed by the plug 92.

  Next, the second cylinder 98 supported by the support board 86 is urged to move the second rod 100 forward toward the case member 18. As a result, the closing member 102 provided at the tip of the second rod 100 enters the side wall through hole 21 of the case member 18 and closes the side wall through hole 21.

  As a result, all the openings 20 and through-holes of the case member 18 are sealed, and the hollow chamber 24 is cut off from the atmosphere to be airtight.

  Next, the fourth cylinder 148 is energized synchronously, and the fourth rod 150 is lowered simultaneously. Following this, the partition member 14 descends, and finally the bottom wall is seated on the upper end surface of the mounting table 12. Thereby, the chamber 16 is formed. The space between the bottom wall of the partition wall member 14 and the upper end surface of the mounting table 12 is sealed by the third seal member 108.

  Next, the gas leakage inspection apparatus 10 is calibrated. Specifically, the first fan 94 and the second fan 110 are energized, and the gas in the monitor space 69 moves from the left to the right or vice versa, and from above to below or vice versa. Creates a moving flow. In this state, the third valve 76 is opened and the reference gas is supplied from the reference gas supply means (such as a cylinder). Thereafter, the reference gas passes through the reference gas introduction pipe 66, is led out from the leak master 68 into the chamber 16, and further rises in the chamber 16 to reach the monitor space 69.

  The flow rate of the reference gas derived from the leak master 68 to the chamber 16 and thus to the monitor space 69 is constant at a predetermined flow rate set in advance. It should be noted that the derived amount or derived flow rate of the reference gas into the chamber 16 is preferably set to the same value as the derived amount or derived flow rate of the inspection gas into the hollow chamber 24 at the time of a leak test described later.

  The reference gas is mixed with the gas existing in the monitor space 69, that is, the atmosphere.

  When the reference gas is helium, helium is lighter than air, and therefore tends to stay near the ceiling wall in the monitor space 69. In particular, when the corner of the monitor space 69 is angular, a light gas such as helium easily stays in the corner and localizes. For this reason, it is not easy for the reference gas to reach the detector 122 via the forward piping 118 and the sampling line 121. Therefore, it is not easy to evaluate the exact amount of the reference gas in the monitor space 69.

  However, in this embodiment, the gas in the monitor space 69 is agitated under the action of the first fan 94 and the second fan 110. In addition, since the curved portion 144 is formed at the corner portion of the partition wall member 14, the gas easily flows along the curved portion 144. For these reasons, even when a light gas such as helium is used as the reference gas, the reference gas is prevented from being localized in the monitor space 69.

  While the reference gas is derived from the leak master 68, the gas in the monitor space 69 defined between the support plate 86 and the ceiling wall of the partition wall member 14 is sucked under the action of the intake pump 123, and the forward path It is sent to the detector 122 via the pipe 118 and the sampling line 121. That is, the gas present in the monitor space 69 is a sampling gas extracted for inspection by the detector 122.

  In the present embodiment, the reference gas is prevented from being localized in the monitor space 69 for the reasons described above. Accordingly, the sampling gas contains the reference gas in a substantially constant amount.

  A part of the sampling gas guided to the outward piping 118 is sent to the detector 122 via the outward piping 118 and the sampling line 121. In addition, since the remainder of the sampling gas is returned to the monitor space 69 via the return pipe 120, the sampling gas containing a stable amount of the reference gas is introduced into the detector 122 during calibration. For this reason, it is possible to calibrate the gas leakage inspection apparatus 10 with high accuracy in accordance with the amount of reference gas introduced into the monitor space 69.

  The detector 122 detects the reference gas derived from the leak master 68. Here, when the reference gas is helium, the detector 122 calculates a value as a sum of the amount of helium contained in the gas (that is, the atmosphere) in the monitor space 69 and the amount of helium as the reference gas. This value is transmitted as information to the control circuit 156 via the signal line 152. The control circuit 156 recognizes the detected amount at this time as a “reference value”. Note that the atmosphere generally contains about 5 ppm of helium.

  As described above, when calibrating the gas leakage inspection apparatus 10, the case member 18 and the core 56 are set on the mounting table 12, and the sandwiching plate 82, as in the case of performing the leakage inspection. It is preferable to press the case member 18. This is because the conditions for calibration and the conditions for leakage inspection are the same.

  Of course, a case member 18 that does not leak is used. When leakage occurs from the case member 18, the gas leaked from the case member 18 is mixed into the gas in the monitor space 69, so that accurate calibration cannot be performed. This is to avoid this.

  After calibrating in this way, preparations are made to perform a leak test.

  That is, the reference gas is introduced into the chamber 16 including the monitor space 69. If the partition member 14 and the sandwiching plate 82 are raised in this state, the reference gas may remain in the vicinity of the mounting table 12. In this case, when the value indicated by the detector 122 in the leak test exceeds the reference value, it is caused by the test gas leaking from the hollow chamber 24 to the chamber 16 and reaching the monitor space 69, or the residual reference gas. It is difficult to determine whether it is caused. Therefore, the gas existing in the monitor space 69 is exhausted. Note that a specific exhaust method is the same as that at the time of a leak test described later, and is omitted here.

  After the exhaust is finished, the partition wall member 14 and the sandwiching plate 82 are raised. Further, the first cylinder 34 is urged to advance the first rod 36, whereby the mounting table 12 is pulled out to the front of the second support table 30, and then the case member 18 is replaced with one that performs a leak test. To do.

  Thereafter, in the same manner as described above, the first cylinder 34 is re-biased to retract the first rod 36, and then the third cylinder 104 is urged to lower the third rod 106. Furthermore, the second cylinder 98 is urged to advance the second rod 100. As a result, as already described in detail, all the openings 20 and through-holes of the case member 18 are sealed, and the hollow chamber 24 is shut off from the atmosphere and becomes airtight. At the same time, the fourth rod 150 of the fourth cylinder 148 is lowered and the bottom wall of the partition member 14 is seated on the upper end surface of the mounting table 12 to form the chamber 16.

  After making the above preparations, conduct a leak inspection.

  First, the first fan 94 and the second fan 110 are energized, and the gas in the monitor space 69 moves from the left to the right or vice versa, and from the upper to the lower or vice versa. And give rise to

  Next, the first clean pump 58 and the second clean pump 134 are energized, and the first valve 72 is opened. Thereby, gas is exhausted from the hollow chamber 24 of the case member 18. Since the core 56 is accommodated in the hollow chamber 24, the amount of gas to be exhausted is relatively small. For this reason, the time required to exhaust the hollow chamber 24 is shortened.

  At this time, the internal pressure of the hollow chamber 24 is measured by the pressure sensor 71. The measurement result is sent to the control circuit 156 via the signal line 154.

  The actual lowering speed of the internal pressure is compared with a set lowering speed preset in the control circuit 156 based on the measurement result using the case member 18 that is a qualified product. It should be noted that the internal pressure (actual final internal pressure) that has become substantially constant with the passage of a predetermined time is compared with the set final internal pressure that is preset in the control circuit 156 based on the measurement result using the case member 18 that is an acceptable product. You may make it do.

  When the actual lowering speed is less than the set lowering speed, there is a leakage portion in the case member 18 or the seal between the case member 18 and the mounting table 12 or the sandwiching plate 82 is insufficient. There is a possibility. Therefore, in this case, the partition member 14 is raised to expose the case member 18, and the case member 18 is once removed from the mounting table 12.

  Next, whether the first seal member 46, the second seal member 90, the third seal member 108, the plugs 48, 92, the closing member 102, and the like are flawed or not misaligned. Investigate whether there is so-called turning. If there is a cause for such a decrease in the sealing function, these may be exchanged or reattached in a normal position at a normal position.

  When it is determined that there is no cause for lowering the sealing function, the leakage portion of the case member 18 is specified, and those that can be repaired are repaired at the repair station. Then, each above-mentioned process is carried out again.

  Instead of removing the case member 18 from the mounting table 12, the inspection gas may be introduced into the hollow chamber 24 as described later, and the leakage location may be specified by the probe 128.

  On the other hand, when the actual descent speed is equal to or higher than the set descent speed, or when the actual final internal pressure is equal to or lower than the set final internal pressure, there is a low possibility that the case member 18 has a leakage portion, and the case member 18 and the mounting table 12 or the sandwiching plate It can be determined that a seal with 82 is sufficient. In this case, the case member 18 is determined to be a pre-accepted product, and the subsequent steps are performed.

  That is, next, after closing the first valve 72, the second valve 74 is opened, and the inspection gas is supplied from the inspection gas supply means (cylinder or the like) to the hollow chamber 24 through the inspection gas introduction pipe 62. The inspection gas is introduced into the hollow chamber 24 at a constant flow rate until a predetermined pressure set in advance is reached. Since the core 56 is accommodated in the hollow chamber 24, the amount of inspection gas to be introduced is relatively small. For this reason, the time required for the hollow chamber 24 to be filled with the inspection gas is shortened.

  Thus, by accommodating the core 56 in the hollow chamber 24, the time required to exhaust the gas in the hollow chamber 24 and the time required to fill the hollow chamber 24 with the inspection gas are shortened. It becomes possible. Therefore, the tact time from the start to the end of the leak test can be shortened.

  Even after the hollow chamber 24 is filled with the inspection gas, the gas in the monitor space 69 is stirred under the action of the first fan 94 and the second fan 110 in the same manner as described above, and the curved portion at the corner of the partition wall member 14 is stirred. Easily flows along 144. Finally, the gas present in the monitor space 69 is led out to the forward piping 118 as a sampling gas, and a part thereof is led to the detector 122 via the sampling line 121. The remaining portion that has not been led to the detector 122 passes through the return pipe 120 and returns to the monitor space 69 in the same manner as described above. In other words, in the present embodiment, it is inspected whether or not there is a leak location in the case member 18 without exhausting the gas (atmosphere) in the monitor space 69.

  The detector 122 obtains the amount of the inspection gas contained in the sampling gas, and then sends the value to the control circuit 156 as information via the signal line 152. The control circuit 156 compares this information with the reference value.

  When the case member 18 has no leakage portion, the inspection gas in the hollow chamber 24 does not leak into the chamber 16. Although the detector 122 detects a gas of the same type as a reference gas (for example, helium) that is naturally contained in the gas (that is, the atmosphere) in the monitor space 69, the reference value is a natural value for the gas in the monitor space 69. Since the value is the sum of the amount of the same type of gas as the reference gas present in the gas and the amount of the reference gas (for example, helium) intentionally supplied from the leak master 68, the inspection gas in the hollow chamber 24 When not leaking into the chamber 16, the value measured by the detector 122 does not greatly exceed the reference value.

  In this case, the control circuit 156 determines that the case member 18 is “accepted product”. The case member 18 determined to be an acceptable product is taken out from the gas leakage inspection apparatus 10 and sent to a station that performs the next process.

  Here, an inspection gas for performing the above-described leakage inspection is introduced into the hollow chamber 24 of the case member 18. If the partition member 14 and the sandwiching plate 82 are raised in this state, there is a concern that the inspection gas at the time of the leakage inspection remains in the vicinity of the mounting table 12. In this case, when the value indicated by the detector 122 exceeds the reference value in the next leak test, it is determined whether it is caused by the test gas leaked from the hollow chamber 24 to the monitor space 69 or the residual test gas. It is difficult to judge.

  In order to avoid such an inconvenience, the gas existing in the hollow chamber 24 and the monitor space 69 is exhausted. That is, the second valve 74 and / or the third valve 76 are closed, and the first valve 72, the fourth valve 78, and / or the two-way valve 138 are opened. As a result, the inspection gas and the reference gas in the hollow chamber 24 and the reference gas introduction pipe 66 are sucked into the first clean pump 58 via the first exhaust pipe 60 and the second exhaust pipe 70, and 2 The exhaust gas is exhausted through the outlet pipe 142 under the action of the clean pump 134. The gas in the monitor space 69 is exhausted through the chamber cleaning pipe 140 under the action of the second clean pump 134.

  Prior to this exhaust, the second electromagnetic valve 130 is switched. As a result, the return pipe 120 is closed and the line cleaning pipe 132 is opened. As a result, the gas in the circulation pipe 116 is sucked into the second clean pump 134 via the line cleaning pipe 132. That is, the gas in the circulation pipe 116 is exhausted and cleaning is performed.

  The inspection gas existing in the hollow chamber 24 is recovered through the inspection gas recovery pipe 63 under the action of the recovery pump 158, and further subjected to a cleaning process to increase purity, and then returned to the inspection gas supply source. You may do it. At this time, the fifth valve 79 may be opened.

  Thereafter, the second cylinder 98 is urged to retract the second rod 100, and the closing member 102 is detached from the side wall through hole 21 of the case member 18.

  Next, the partition member 14 and the sandwiching plate 82 are raised by energizing the fourth cylinder 148 and the third cylinder 104 to raise the fourth rod 150 and the third rod 106. If necessary, air may be supplied into the monitor space 69 and the hollow chamber 24 prior to this rise. For this purpose, air introduction pipes for introducing air may be provided in the monitor space 69 and the hollow chamber 24, respectively, and air may be supplied from the air supply source to the air introduction pipe.

  By raising the partition member 14 and the sandwiching plate 82, the case member 18 released from the sandwiching is exposed. Next, the first cylinder 34 is urged to advance the first rod 36, thereby pulling the mounting table 12 forward of the second support 30. Thereafter, the case member 18 is removed from the mounting table 12 by an operator or a robot and is transported to another station. This completes a series of leakage inspections.

  Thereafter, a leak test is performed on the case member 18 that has been transported to the gas leak test apparatus 10 in the same manner as described above. At this time, since the inspection gas used in the previous leakage inspection is removed, it is possible to avoid a decrease in detection accuracy due to the inspection gas in the previous leakage inspection.

  On the other hand, when there is a leak location in the case member 18, the inspection gas introduced into the hollow chamber 24 passes through the leak location and leaks into the chamber 16. When the inspection gas is lighter than air such as helium, the leaked inspection gas (hereinafter also simply referred to as leakage gas) rises up to the monitor space 69 and gas (atmosphere) in the monitor space 69 To mix.

  In the present embodiment, the gas in the monitor space 69 is agitated under the action of the first fan 94 and the second fan 110. In addition, since the curved portion 144 is formed at the corner of the partition wall member 14, the leaked gas easily flows along the curved portion 144. For the above reasons, even when a light gas such as helium is used as the inspection gas, the inspection gas is prevented from being localized in the monitor space 69. That is, in this case, a gas in which a leak gas is added to the atmosphere is guided to the outward piping 118 as a sampling gas.

  Thereafter, in the same manner as described above, a part of the sampling gas passes through the forward piping 118 and the sampling line 121 and then reaches the detector 122, and the remaining portion passes through the return piping 120 and returns to the monitor space 69.

  In this process, the detector 122 indicates a value exceeding the reference value obtained by calibration. This is because the sampling gas introduced to the detector 122 contains leaking gas, and thus the detector 122 indicates the detected amount as the sum of the leaking gas. When the same kind of gas as the inspection gas (for example, helium) is contained in the atmosphere, the detector 122 naturally shows the detected amount including the inspection gas component in the atmosphere.

  The detector 122 transmits the value as information to the control circuit 156 via the signal line 152. Upon receiving this information, the control circuit 156 determines that the case member 18 is “a rejected product”.

  Here, when the diffusion of the leaked gas in the monitor space 69 is not uniform, the concentration (amount) of the leaked gas in the gas differs depending on the sampling location. Therefore, there is a concern that it is impossible to accurately evaluate the exact amount of leaked gas, and hence the size of the leaked portion.

  Further, when inspecting whether leakage occurs from the hollow chamber 24 while exhausting the gas in the monitor space 69, the gas that has leaked from the hollow chamber 24 into the chamber 16 and reached the monitor space 69 in a relatively short time. Will be exhausted. Therefore, when the amount of leaked gas is small, there is a concern that the entire amount of leaked gas is exhausted. Even if it is assumed that a part is exhausted and the remaining part can reach the detector 122, it is unclear how much the leaked gas has been exhausted, so it is difficult to accurately evaluate the amount of leaked gas. .

  Accordingly, it is necessary to wait for a certain amount of time after the introduction of the inspection gas, and to perform a leakage inspection when the amount of leakage gas becomes sufficient. For this reason, the leakage inspection takes a long time.

  Furthermore, even when the pressure in the chamber 16 is atmospheric pressure, for example, if the gas flowing through the exhaust line is a sampling gas, the concentration of the leakage gas in the sampling gas is small when the amount of the leakage gas is small. Even if the amount of leaked gas displayed on the detector 122 is slightly increased, it is difficult to determine whether the value is increased due to the leaked gas or within a measurement error range.

  In addition, when sampling gas is collected from the chamber 16 or the monitor space 69 and measurement is performed, the sampling gas is exhausted as it is, rather than leakage from the hollow chamber 24 of the case member 18. There is also a concern that leakage cannot be detected due to the large amount of exhaust.

  On the other hand, in the present embodiment, a gas flow is generated in the monitor space 69 to prevent the leakage gas from staying. For this reason, even if the leakage gas is extremely small, the leakage gas diffuses substantially evenly without being localized in the monitor space 69. Therefore, since the concentration of the leaked gas is substantially the same regardless of the location where the forward piping 118 is provided, in other words, the sampling location is set to any location, the leakage amount can be evaluated with high accuracy.

  Further, the gas in the monitor space 69 is taken out and a part thereof is supplied to the detector 122, while the remaining portion not supplied to the detector 122 is returned to the monitor space 69 (that is, the gas is circulated). Therefore, the leaked gas in the monitor space 69 is sequentially accumulated, and is sent to the detector 122 at a high concentration. For this reason, it is possible to evaluate the amount of leakage and thus the scale of leakage in real time and with high accuracy.

  That is, according to the present embodiment, it is possible to continuously check the presence or absence of leakage during measurement regardless of the level of leakage, and there is no need to wait for a certain period of time. Further, even when the capacity of the hollow chamber 24 of the case member 18 is large, the leakage can be easily detected even when the leakage amount is very small.

  It should be noted that if the derived amount or derived flow rate of the inspection gas into the hollow chamber 24 is matched with the derived amount or derived flow rate of the reference gas into the chamber 16, the amount of inspection gas leaked from the hollow chamber 24 is further increased. It can be evaluated with high accuracy.

  Further, when the leak inspection is performed while exhausting the gas in the chamber 16, the exhaust means such as a pump frequently fails. In the case of failure, leakage inspection cannot be performed until the repair of the exhaust means is completed, resulting in a time loss. However, in this embodiment, such inconvenience is not caused.

  In the present embodiment, the display value of the detector 122 when the reference gas is used is calibrated as the reference value, so the reference value is the same type of gas as the reference gas naturally present in the atmosphere (for example, helium). ). Therefore, even when the same type of gas as this gas is used as the reference gas and the inspection gas, the detector 122 displays a value based on the amount of leaked gas. That is, it is avoided that the detection accuracy of the leaked gas is lowered by the same kind of gas as the reference gas existing in the atmosphere.

  As described above, the leakage gas is detected by the detector 122, and the case member 18 in which the control circuit 156 determines that the leakage portion is present is then examined where the leakage portion is present. . In order to perform this investigation, after exhausting the gas in the chamber 16 under the action of the second clean pump 134, the fourth rod 150 is raised to raise the partition member 14. As a result, the case member 18 that is sandwiched between the mounting table 12 and the sandwiching plate 82 and in which the inspection gas is introduced into the hollow chamber 24 is exposed. Note that air may be supplied into the chamber 16 prior to the rise of the partition member 14.

  Next, the first solenoid valve 124 is switched. Along with this, the outward piping 118 is closed, while the probe piping 126 is opened. Therefore, the gas sucked by the probe 128 is guided to the detector 122.

  The operator grips the probe 128 and brings its tip close to the case member 18, and further scans the probe 128 along the case member 18. Since the leaked gas is not leaked at the portion that is not the leaked portion, the leaked gas is not sucked into the probe 128. Therefore, the display value of the detector 122 does not increase based on the leaked gas.

  On the other hand, at the leak location, leak gas is sucked by the probe 128. Since the concentration of the leaked gas is high in the vicinity of the leak location, the display value of the detector 122 rises in a relatively short time. Thereby, it is possible to roughly determine where the leakage point exists.

  When the second cylinder 98 is provided on the partition member 14, the partition member 14 can be raised unless the second rod 100 is retracted and the closing member 102 is separated from the side wall through hole 21 of the case member 18. Can not. Therefore, in this case, when the partition member 14 is raised, the case member 18 is exposed in a state where the hollow chamber 24 communicates with the atmosphere. That is, since the inspection gas in the hollow chamber 24 is led out from the side wall through-hole 21, it is impossible to determine where the leakage point is as described above.

  On the other hand, in the present embodiment, since the second cylinder 98 is provided on the sandwiching plate 82, the partition member 14 does not interfere with the second cylinder 98. Therefore, the fourth rod 150 and the partition member 14 can be raised without retracting the second rod 100, in other words, with the closing member 102 inserted into the side wall through hole 21 of the case member 18. it can. That is, since the case member 18 in the state in which the inspection gas is sealed in the hollow chamber 24 can be exposed, the approximate position of the leaked portion can be determined by the probe 128.

  After specifying the approximate leak location, the test gas present in the hollow chamber 24 is exhausted under the action of the first clean pump 58. The inspection gas is exhausted under the action of the second clean pump 134 after passing through the outlet pipe 142.

  At this time, when the size of the leaked portion (such as a casting defect) is small, the exhaust speed is relatively large and the degree of vacuum is relatively large. Thus, when the scale of leakage is extremely small and there is no practical problem, the case member 18 is determined to be “accepted product”.

  Thereafter, the second cylinder 98 is urged to retract the second rod 100, and thereby the closing member 102 is detached from the side wall through hole 21 of the case member 18. Further, the third cylinder 104 is energized to raise the third rod 106 and raise the sandwiching plate 82. As a result, the case member 18 is released from clamping. If necessary, air may be supplied into the hollow chamber 24 prior to the removal of the blocking member 102 from the side wall through hole 21 and the raising of the sandwiching plate 82.

  Next, the first cylinder 34 is urged to advance the first rod 36, thereby pulling the mounting table 12 forward of the second support 30. Thereafter, the case member 18 is removed from the mounting table 12 by an operator or a robot, and is transported to a station where the next process is to be performed.

  On the other hand, when the size of the leak location is large, the exhaust speed is small. Also, the degree of vacuum reached is small. This is because air is sucked into the hollow chamber 24 from the leaked portion.

  In this case, leakage that cannot be ignored occurs from the leakage point. Such a case member 18 is determined to be “a rejected product”.

  When the above-described leakage test is performed on the case member 18 having a different shape and height direction dimension, the mounting table 12, the columns 80a to 80d, the stopper 50, and the sealing member 84 correspond to the case member 18. What is necessary is just to exchange for the thing of a shape thru | or a size. As can be understood from this, the gas-type leak inspection apparatus 10 according to the present embodiment has versatility that can correspond to a wide variety of case members 18.

  The present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the present invention.

  For example, leakage inspection may be performed using an object other than the case member 18 as a workpiece.

  Further, the inspection gas is not limited to helium, and may be hydrogen or the like. Of course, the same kind of gas is used as the reference gas and the inspection gas. When using hydrogen, it is preferable to adopt an explosion-proof structure.

DESCRIPTION OF SYMBOLS 10 ... Gas-type leak inspection apparatus 12 ... Mounting stand 14 ... Partition member 16 ... Chamber 18 ... Case member 20 ... Opening 21 ... Side wall through-hole 22 ... Ceiling wall through-hole 24 ... Hollow chamber 26 ... Base 34 ... 1st cylinder 36 ... first rod 44 ... first annular groove 46 ... first seal members 48, 92 ... plug 50 ... stopper 56 ... core 58 ... first clean pump 60 ... first exhaust pipe 62 ... inspection gas introduction pipe 63 ... Pipe for inspection gas recovery 66 ... Reference gas introduction pipe 68 ... Leak master 69 ... Monitor space 70 ... Second exhaust pipe 71 ... Pressure sensors 80a to 80d ... Strut 82 ... Nipping plate 88 ... Second annular groove 90 ... Second Seal member 94 ... first fan 98 ... second cylinder 100 ... second rod 102 ... blocking member 104 ... third cylinder 106 ... third rod 108 ... third seal member 110 ... first 2 fan 116 ... circulation pipe 118 ... forward pipe 120 ... return pipe 121 ... sampling line 122 ... detector 124 ... first solenoid valve 126 ... probe pipe 128 ... probe 130 ... second solenoid valve 132 ... line cleaning pipe 134 ... Second clean pump 136 ... Cleaning hole 138 ... Two-way valve 140 ... Chamber cleaning pipe 142 ... Outlet pipe 144 ... Bending portion 148 ... Fourth cylinder 150 ... Fourth rod 152, 154 ... Signal line 156 ... Control circuit

Claims (9)

A gas leakage inspection device for inspecting whether there is leakage from the wall of the workpiece,
The base,
A mounting table provided on the base for positioning and fixing the workpiece;
A clamping board for clamping the workpiece together with the mounting table;
A sandwiching plate displacement mechanism that is supported by the base and displaces the sandwiching plate toward or away from the workpiece;
A partition member that forms a chamber that approaches or separates from the mounting table and surrounds the workpiece when contacting the mounting table;
A partition member displacement mechanism supported by the base for displacing the partition member in a direction approaching or separating from the mounting table;
Exhaust means for exhausting air from a hollow chamber formed by the wall portion of the workpiece;
Inspection gas supply means for supplying inspection gas to the hollow chamber;
Sampling gas discharged from a monitor space defined between the holding plate that is in contact with the workpiece in the chamber and the partition member that is in contact with the mounting table and forms the chamber is the monitor space. A circulation flow path to return to
Inspection gas detection means for supplying the sampling gas via the circulation flow path;
With
When the sampling gas contains the inspection gas, the inspection gas detection means detects the inspection gas, and a gas type leak inspection apparatus characterized by the above.   The gas leakage inspection apparatus according to claim 1, wherein a seal member is provided at a portion that contacts the workpiece of at least one of the mounting table and the clamping board.   3. The apparatus according to claim 1, further comprising a plurality of support members having a height direction dimension equal to a height direction dimension of the workpiece, wherein the support member includes the mounting table and the sandwiching plate. A gas type leakage inspection apparatus that supports the clamping board when the workpiece is clamped.   The gas leakage inspection apparatus according to any one of claims 1 to 3, further comprising a plurality of stirring means for stirring the gas in the monitor space.   The apparatus according to any one of claims 1 to 4, wherein at least one of the stirring means is provided on the sandwiching plate, and forms a flow along a vertical direction in the gas in the monitor space. Gas leak inspection device.   6. The gas leakage inspection apparatus according to claim 5, wherein at least one of the stirring means is provided on a side wall of the chamber and forms a flow along a horizontal direction in the gas in the monitor space.   7. The gas leakage inspection apparatus according to claim 5, further comprising a core disposed in the hollow chamber to reduce a space volume of the hollow chamber.   The gas leakage inspection apparatus according to any one of claims 1 to 7, wherein an inner corner of the partition member is curved.   9. The gas leakage inspection apparatus according to claim 1, wherein mounting base displacement means for displacing the mounting base is provided on the base.

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