JP4128093B2 - Seal inspection device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an inspection apparatus for detecting leakage of a sealed body.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in various fields such as foods, medicines, and cosmetics, in order to prevent product deterioration and ensure safety, the product is sealed with a package to block it from the outside air. In such a sealed package, if there are pinholes or cracks, the sealing function is impaired, so the product is sealed and checked for leaks to ensure reliability. Secured. As an inspection apparatus used for this inspection, an air leak type and a gas analysis type are known. The measurement principle of the air leak type inspection device is that the product to be inspected is put in the chamber, the pressure in the chamber is reduced, the pressure fluctuation in the chamber is detected, and the pressure in the chamber is kept in equilibrium. The presence or absence of leakage of the hermetic package is determined. On the other hand, the measurement principle of the gas analysis type inspection apparatus is that a specific gas such as a small amount of helium gas is sealed in advance in the sealed package of the product, and the gas detection probe is brought close to the sealed package to detect the specific gas. If there is a leak, it is determined that there is a leak. Such a gas analysis type inspection apparatus is described in Patent Document 1, for example. The inspection apparatus described in Patent Document 1 discloses that the internal packaging gas is caused to flow out from a pinhole or the like by vibrating a sealed package from the outside, thereby increasing detection sensitivity.
[0003]
[Patent Document 1]
JP 2002-107261 A
[Problems to be solved by the invention]
Since the conventional gas analysis type inspection device cannot detect the leak unless the specific gas leaking from the sealed package reaches the gas detection probe, if the leak point such as a pinhole is away from the gas detection probe, The detection sensitivity tends to decrease. Moreover, although the structure which vibrates a sealed package body and makes internal gas flow out like patent document 1 is effective when there is much gas amount inside a sealed package body, the quantity of internal gas is If it is small, it is not effective.
[0005]
An object of the present invention is to detect leakage of a sealing body with high sensitivity even when the amount of gas inside the sealing body is small.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, in the present invention, when the sealing body is leaked, the internal gas is pushed out by pressing the sealing body with an elastic body. At this time, the sealed body is covered with a container, and the elastic body is disposed inside the container, so that the gas detection unit detects the pushed gas without escaping to the outside. Further, by using an air permeable material as the elastic body, the extruded gas can pass through the elastic body and reach the gas detection unit, and can be detected quickly.
[0007]
Specifically, it can be configured as follows. It is set as the structure which has the container for covering the sealing body which is a test object, and the gas analysis part for analyzing whether the gas of the internal space of a container contains specific gas. An elastic body for compressing the inspection object is arranged inside the container. An elastic body is used that has air permeability, and the gas pushed out from the detection target passes through the elastic body and reaches the gas analysis section.
[0008]
Moreover, it can comprise so that it may further have a conveyance part for conveying a test object, and the drive part which moves a container. In this case, a container having a downward opening is used, and the driving unit covers the inspection object from above and moves the inspection object to follow the movement of the inspection object by the transport unit.
[0009]
Moreover, it can be set as the structure which has arrange | positioned the pipe | tube which connects these between a gas analysis part and a container. In this case, the gas analysis unit is configured to suck and analyze the gas pushed out from the inspection object being conveyed by the conveyance unit from the container.
[0010]
Moreover, the above-mentioned conveyance part can be set as the structure containing the conveyor belt which mounts and carries a test object. In this case, the drive unit is configured to press the opening of the container placed on the inspection target against the conveyor belt, and the conveyor belt can be configured such that the region on which the inspection target is mounted has air permeability.
[0011]
A second container having an upward opening can be disposed below the conveyor belt. In this case, the gas analyzer is configured to analyze the gas in the internal space of the second container.
[0012]
In addition, a second elastic body can be disposed inside the second container. Thereby, the inspection object is sandwiched between the elastic body in the upper container and the second elastic body in the lower second container together with the conveyor belt, and the upper elastic body and the lower second elastic body. The elastic body can be compressed in conformity with the shape of the inspection object to compress the entire inspection object.
[0013]
Further, the upper elastic body and the lower second elastic body described above are released from the compressed state following the shape of the object to be inspected and expand to temporarily become a negative pressure inside the object to be inspected. It is also possible to adopt a configuration for sucking out the gas inside.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
A sealing body leakage inspection apparatus according to an embodiment of the present invention will be described with reference to the drawings.
[0015]
In this embodiment, the sealed body is a sealed package in which the product is sealed with a package, and the product itself has a sealed structure such as an air bag starter for an automobile, a tank, and a small sealed part. Including a sealing body.
[0016]
First, a leak inspection apparatus according to the first embodiment will be described with reference to FIG. As shown in FIG. 1, the leakage inspection apparatus includes a transport unit 10 that transports a sealing body 1 that is a detection target, a cover unit 20 that covers the sealing body 1 that is transported to the transport unit 10, and a cover unit 20. Is driven at the same speed as the transport speed of the transport section 10, a gas analysis section 40 that performs gas analysis by sucking the gas inside the cover section 20, and a control section 50.
[0017]
As shown in FIG. 1 and FIG. 2, which is a cross-sectional view taken along the line AA ′, the transport unit 10 includes a conveyor belt 11, a roller unit 12 that moves the conveyor belt 11, and a pair of rails 13. Yes. The rail 13 is disposed along a path along which the conveyor belt 11 conveys the sealing body 1, and supports the conveyor belt 11 on which the sealing body 1 is mounted in a movable manner. Moreover, the conveyor belt 11 is comprised so that the area | region 11a (refer FIG. 2) which mounts the sealing body 1 may have air permeability. Specifically, the region 11a of the conveyor belt 11 on which the sealing body 1 is mounted has a mesh structure provided with a large number of small holes, or is made of a material having air permeability. The sealing body 1 is supplied and conveyed on the conveyor belt 11 one by one by a supply unit (not shown). As the supply unit, for example, another belt conveyor disposed so as to be connected to the transport unit 10 or a structure in which the sealing body 1 is mounted on the conveyor belt 11 from above can be used.
[0018]
As shown in the perspective view and the cross-sectional view in FIGS. 3A and 3B, the cover portion 20 includes a container 21 having an opening at the entire bottom surface, and a breathable elasticity filled in the container 21. And a body 22. As the breathable elastic body 22, for example, a foam material such as urethane can be used. In the upper part of the container 21, an exhaust hole 23 is provided, and a suction pipe 41 of the gas analysis unit 40 is connected. Thereby, the gas inside the container 21 is sent from the exhaust hole 23 through the suction pipe 41 to the gas analysis unit 40. At this time, the air-permeable region 11a of the conveyor belt 11 acts as an intake hole. Therefore, when the container 21 is covered from the upper part of the sealing body 1, the air-permeable elastic body 22 and the conveyor belt 11 sandwich the sealing body 1, and the elastic body 22 presses this according to the outer shape of the sealing body 1. . As a result, when there is a defect such as a pinhole in the sealing body 1, the internal gas is pushed out, and the extruded gas passes through the breathable elastic body 22 without being exhausted to the outside of the container 21. It is sent from the hole 23 through the suction pipe 41 to the gas analyzer 40 and analyzed whether or not a specific gas is contained.
[0019]
Moreover, the connection part 24 is provided in the upper part of the container 21 of the cover part 20 like Fig.3 (a). As shown in FIG. 4, the drive unit 30 that drives the cover unit 20 includes four extendable shafts 32 connected to the connection unit 24, a cam 31 connected to each of the shafts 32, and a cam 2 that rotates the cam 31. The rotary shaft 33 of the book and the drive source 34 are included. The drive source 34 rotationally drives the two rotary shafts 33 and translates the rotary shaft 33 along the conveying direction of the conveyor belt 11. A spring 32 a is inserted around the extendable shaft 32.
[0020]
When the drive source 34 rotates the rotating shaft 33, the container 21 moves up and down as the cam 31 rotates. By this vertical movement, the container 21 can be covered from above the sealing body 1. Further, the container 21 is pressed against the conveyor belt 11 with a constant pressure by the action of the spring 32a. The drive source 34 rotates the rotating shaft 33 at the same speed as the moving speed of the conveyor belt 11 from the start point 60a to the end point 60b of the inspection section 60 set in the conveying section of the conveyor belt 11 while continuously rotating the rotating shaft 33. Is translated. When the container 21 reaches the end point 60b, the container 21 is moved in the reverse direction to the start point 60a. Thus, the container 21 moves along the locus shown in FIG. 5 by causing the drive source 34 to translate while rotating the rotary shaft 33 . That is, between the start point 60a and the end point 60b of the inspection section 60 (see FIG. 1) set in the transport section of the conveyor belt 11, the container 21 is in contact with the conveyor belt 11 and at the same speed in the same direction as the conveyor belt 11. Moving. When the end point 60b of the inspection section 60 is reached, the container 21 is lifted upward by the drive unit 30 by the movement of the cam 31 and is detached from the sealed body 1, and moves in the direction opposite to the moving direction of the conveyor belt 11. And return to the starting point 60a again. By moving the container 21 in this way, a leakage inspection can be performed while the sealing body 1 is being transported through the inspection section 60 by the conveyor belt 11.
[0021]
The gas analysis unit 40 includes a suction tube 41 communicating with the container 21, a suction unit that sucks gas from the suction tube 41, and an analysis unit that analyzes whether the gas sucked by the suction unit contains a specific gas species. Including. The suction pipe 41 is set to have a sufficient length so that the container 21 can follow the movement of the container 21 by the drive unit 30. The suction unit and the analysis unit are built in the gas analysis unit 40 and are not shown in FIG. In this embodiment, helium gas is used as the specific gas type.
[0022]
The control unit 50 controls the operation of the drive unit 30 and the operation of the transport unit 12 and receives an analysis result from the gas analysis unit 40. When helium gas which is a specific gas is detected, It is determined that there is a leak in the sealed body 1 that has passed through the inspection section 60.
[0023]
Next, the operation of each part when performing the inspection with the leakage inspection apparatus of the present embodiment will be described.
[0024]
As the sealed body 1 to be examined, a sealed body in which a small amount of helium gas is sealed at the time of sealing is used. On the conveyor belt 11 of the conveyance part 10, the sealing body 1 is supplied one by one by the supply part which is not illustrated. The control unit 50 operates the transport unit 10 to transport the sealing body 1 by the conveyor belt 11. Further, the control unit 50 operates the driving unit 30 to move the cover unit 20 so as to draw the trajectory of FIG. 5, and the cover unit 21 is moved from above the sealing body 1 that has reached the starting point 60 a of the inspection section 60. Cover. Thereby, as shown in FIG. 1 and FIG. 2, the sealing body 1 is in a state where the lower surface is supported by the conveyor belt 11 and the upper surface and side surfaces are completely covered by the container 21 of the cover portion 20. The sealing body 1 is conveyed in the inspection section 60 by the conveyor belt 11 in this state, and the cover unit 20 also moves in the inspection section 60 following this. While the sealing body 1 is being transported through the inspection section 60, the sealing body is inspected for leaks as follows. The sealing body 1 is pressed by the breathable elastic body 22 inside the cover portion 20 due to the covering of the cover portion 20, and when the sealing body 1 has a defect such as a pinhole, the sealing body 1 The gas inside 1 is extruded. At this time, the elastic body 22 is compressed according to the outer shape of the sealing body 1 and presses the sealing body 1, so that the gas inside the sealing body 1 can be pushed out efficiently. In addition, since the sealed body 1 is covered with the container 21 and the internal space of the container 21 is sucked by the gas analysis unit 40, the pushed-out gas does not spread outside the container 21, but spreads to the gas analysis unit 40. It is taken in and analyzed for the presence of helium gas. The analysis result is output to the control unit 50. When the sealing body 1 reaches the end point 60 b of the inspection section 60, the cover unit 20 is lifted by the movement of the cam 31 of the driving unit 30 and is removed from the sealing body 1. As the cover portion 20 is raised, the elastic body 22 is released from the state of being compressed by being pressed against the sealing body 1, and thus expands to the original shape. During the expansion, the inside of the elastic body 22 which is a porous body temporarily becomes a negative pressure, and an action of sucking out gas from the inside of the sealed body 1 is obtained. Thereafter, the raised cover portion 20 returns to the start point 60a of the inspection section 60 as shown in FIG. 5, and inspects the sealed body 1 to be transported next.
[0025]
When the control unit 50 receives the result that helium gas is detected from the gas analysis unit 40, the control unit 50 determines that the sealed body 1 has a leak. Then, the determination result is notified to the user, and if necessary, another conveying means (not shown) is operated to switch the conveying route, so that the conveying route of the leaky sealed body 1 is changed to the defective item conveying route. Controls such as switching.
[0026]
As described above, in the leakage inspection apparatus according to the present embodiment, since the sealing body 1 is pressed by the elastic body 22, when the amount of gas inside the sealing body 1 is small or the shape of the sealing body 1 is uneven. Even in some cases, the sealing body 1 can be pressed according to the shape of the sealing body 1. Thereby, internal gas can be rapidly and reliably extruded from defects, such as a pinhole of the sealing body 1. FIG. Further, since the sealed body 1 is covered with the container 21, the extruded gas can be taken into the gas analysis unit 40 without being diffused outside the container 21. Thereby, when there is a leak in the sealing body 1, it can be quickly detected with high sensitivity.
[0027]
Moreover, since the leak test | inspection apparatus of this Embodiment is a structure which moves the cover part 20 following the sealing body 1, it can perform a leak test in the middle of conveying the sealing body 1. FIG. Therefore, 100% inspection can be performed while maintaining manufacturing efficiency by incorporating the leak inspection apparatus of the present embodiment into the manufacturing line of the sealed body 1.
[0028]
In the above-described embodiment, the gas analysis unit 40 and the container 21 are connected by the suction pipe 41. However, the present invention is not limited to this configuration, and the gas analysis unit 40 is arranged above the container 21. Alternatively, it may be arranged inside and moved together with the container 21. In this case, the suction tube 41 is not necessary.
[0029]
Next, a leakage inspection apparatus according to the second embodiment will be described with reference to FIG. As shown in FIG. 6, the leak inspection apparatus according to the second embodiment has the same configuration as the leak inspection apparatus according to the first embodiment, but the lower cover portion 70 is disposed on the lower surface side of the conveyor belt 11. Is. The configuration other than the lower cover portion 70 is the same as that of the leak inspection apparatus of the first embodiment. The lower cover portion 70 includes a container 71 and an elastic body 72 disposed inside the container 71. The container 71 is fixed between the pair of rails 13 so as to face the container 21 of the cover unit 20 with the conveyor belt 11 interposed therebetween. Therefore, the lower cover part 70 does not move like the upper cover part 20. The opening of the container 71 is equivalent to the container 21 of the cover portion 20 in the width direction, but has a length that covers the entire region of the inspection section 60 in the longitudinal direction. An exhaust hole 73 is provided in the container 71 of the lower cover part 70, and the suction tube 42 connected to the suction part of the gas analysis unit 40 is connected to the exhaust hole 73. Thereby, the gas in the internal space of the container 71 is sent to the gas analysis unit 40.
[0030]
The operation of the leak inspection apparatus according to the second embodiment will be described. In the leak inspection apparatus of the second embodiment, the sealing body 1 is sandwiched between the elastic body 22 of the cover portion 20 and the elastic body 72 of the lower cover portion 70, and the elastic body 22 and the elastic body 72 are connected to the sealing body 1. The upper and lower shapes are respectively deformed, and the sealing body 1 is pressed from above and below. Thereby, the gas inside the sealing body 1 can be effectively pushed out from a pinhole or the like. The pushed-out gas is collected by the upper cover part 20 and the lower cover part 70, and is sucked by the gas analysis part 40 from the suction pipes 41 and 42 and analyzed. Therefore, even when the pinhole of the sealing body 1 exists on the side where the sealing body 1 comes into contact with the conveyor belt 11 and the extruded gas leaks downward from the air-permeable region 11a of the conveyor belt 11. The container 71 of the lower cover 70 can be reliably captured in the internal space and can be quickly sent to the gas analyzer 40. In this way, by pressing the sealing body 1 from above and below, gas can be quickly pushed out from a pinhole or the like, captured by the upper cover part 20 and the lower cover part 70, and sent to the gas analysis part 40 quickly. Sensitivity can be further increased. Further, as in the first embodiment, as the cover portion 20 is raised, the elastic bodies 22 and 72 are released from the state of being compressed by being pressed against the sealing body 1, so that the original shape When it expands to the inside, the inside temporarily becomes a negative pressure, and the action of sucking out gas from the inside of the sealing body 1 is also obtained.
[0031]
【The invention's effect】
As described above, according to the present invention, it is possible to detect leakage of the sealed body with high detection sensitivity even when the amount of gas inside the sealed body is small.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing an overall configuration of a leakage inspection apparatus according to an embodiment of the present invention.
2 is a cross-sectional view taken along the line AA ′ of the cover unit 20 and the transport unit 10 of the leak inspection apparatus of FIG. 1;
FIG. 3A is a perspective view of a cover portion 20 of the leakage inspection apparatus of FIG. (B) is BB 'sectional drawing of the cover part 20 of (a).
4 is a perspective view showing a configuration of a drive unit 30 of the leakage inspection apparatus of FIG. 1. FIG.
5 is an explanatory diagram showing a locus of a point A of the cover unit 20 driven by the driving unit 30 of FIG.
FIG. 6 is a cross-sectional view showing a configuration of a leak inspection apparatus according to a second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Sealing body, 10 ... Conveyance part, 11 ... Conveyor belt, 12 ... Roller part, 13 ... Rail, 20 ... Cover part, 21 ... Container, 22 ... Elastic body, 23 ... Exhaust hole, 24 ... Connection part, 30 ... Drive unit, 31 ... cam, 32 ... telescopic shaft, 33 ... rotating shaft, 34 ... drive source, 40 ... gas analysis unit, 41 ... suction tube, 42 ... suction tube, 50 ... control unit, 60 ... inspection section, 70 ... lower cover, 71 ... container, 72 ... elastic body.

Claims (7)

A container for covering the sealed body to be inspected, and a gas analyzer for analyzing whether or not the gas in the internal space of the container contains a specific gas,
An elastic body for compressing the inspection object is arranged inside the container, and the elastic body has air permeability between the inspection object and the inside of the container, and is pushed out of the detection object. The gas inspection apparatus according to claim 1, wherein the gas passes through the elastic body and reaches the gas analysis unit. The leak inspection apparatus according to claim 1, further comprising a transport unit for transporting the inspection object, and a drive unit for moving the container,
The container comprises a downward opening;
The drive unit covers the inspection object from above and moves the container to follow the movement of the inspection object by the transport unit. In the leak inspection apparatus according to claim 1 or 2, a pipe for communicating them is disposed between the gas analysis unit and the container.
The gas analyzer is configured to suck and analyze the gas inside the container from the container through the tube. The leak inspection apparatus according to claim 2, wherein the conveyance unit includes a conveyor belt that carries the inspection object and conveys the inspection object,
The drive unit is configured to press the opening of the container over the inspection object against the conveyor belt,
The leak inspection apparatus according to claim 1, wherein the conveyor belt has an air permeability in a region where the inspection object is mounted. The leak inspection apparatus according to claim 4, wherein a second container having an upward opening is disposed below the conveyor belt,
Between the gas analysis part and the second container, a second pipe is provided for communicating them, and the gas analysis part passes the gas in the internal space of the second container to the second pipe. Leakage inspection device characterized by being sucked through and analyzed. 6. The leak inspection apparatus according to claim 5, wherein a second elastic body is disposed inside the second container, and the inspection target includes the elastic body in the upper container together with the conveyor belt. It is sandwiched between the second elastic body in the second container on the lower side, and the elastic body and the second elastic body are compressed following the shape of the inspection object, and the entire inspection object is Leak inspection device characterized by being configured to press. The leak inspection apparatus according to claim 6, wherein the elastic body and the second elastic body are released from a compressed state following the shape of the inspection target and are expanded to temporarily have a negative pressure inside. And leaking the gas inside the inspection object.

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