JP4086789B2 - Method and apparatus for leak inspection of packaging container with stopper - Google Patents

Description

  The present invention relates to a method and an apparatus for performing an air leakage inspection of a plug portion in a packaging container using a pressure resistant chamber.

  As shown in FIG. 3, when drinking water, for example, is enclosed in a wrapping bag 10 formed by two folded films 12 and 13, the wrapping bag 10 is equipped with an opening stopper 11 at the outlet portion of the drinking water. . As for the shape of the stopper 11, there is a statistic that the base 14 that is sandwiched between the folded films 12 and 13 and welded to the canoe type, that is, the ship shape, has the best sealing performance. A stopper 11 is used. However, structurally, there is a problem that a gap is easily generated between the both ends 15 of the boat-shaped pedestal portion 14 and the folded films 12 and 13.

  Conventionally, as a hermeticity inspection of this type of package, a method is used in which the package is housed in a pressure-resistant chamber, the pressure of the chamber is reduced, and air pressure leaking from the package to the chamber is detected. In other words, if there is a pinhole in the already-sealed portion, the pressure in the pressure-resistant chamber increases due to air leakage. Therefore, the leakage of the package is detected by measuring the change in pressure.

  The above inspection method will be described with reference to FIG. 6. Air is sucked into a pressure-resistant chamber that accommodates a completely sealed vacuum package, and the set time t when the pressure value P of the chamber reaches a complete vacuum value of 0 Mps. Measure the pressure in the chamber, and if there is an error in the ultimate pressure value P2, it is detected that there is a delay in the pressure drop like the virtual line P3 due to air leakage from the vacuum package. It can be done.

However, the error P2 is not always measurable as shown in the figure depending on the size of the pinhole, and the reduced pressure value P of the chamber is not completely measured at the set time t depending on the ambient temperature or the moisture ratio of air. Since the vacuum does not always reach 0 Mps, there was a problem that this measurement was somewhat incomplete.
JP 59-133445 A Japanese Patent Laid-Open No. 10-211901

  The main feature of the problem to be solved is that the change in the conditions in the chamber when pinholes exist in the sealed package, which is the inspection object, can be detected with high probability and efficiency.

  As a method for increasing the pinhole detection effect of a cap with a lid, the present invention concentrates on both ends of the boat's pedestal in the chamber so that the cap with a lid is surrounded by a pair of small chambers. The air in the chamber is forcibly aspirated while holding the air from the outside with a clamping body to prevent air leakage from the pinhole. Simultaneously with the opening of the bar, the sensor is used to detect a change in the condition in the chamber and to perform a leak test.

  It is configured to detect air leakage from the pinhole of the lid with a lid of the sealed package by changing the conditions in a small chamber surrounding the plug, and at the same time as opening a pair of clamping bars that seal the pinhole, Since the condition change of the small chamber with a small volume is detected, the condition change is conspicuous, and there are advantages that the inspection result is accurate and the inspection efficiency is improved.

  A small chamber can be measured if it has a minimum internal volume surrounding the cap with a lid and a movement space of the sandwiching body. Note that the stopper with a lid indicates a screw-type lid, a push-in lid, or a cut-type open lid.

  As shown in the side cross-section of FIG. 2, the figure shows a small chamber 20 formed by a pair of boxes 21 and 22 on both sides of a guide rod 23 arranged horizontally and slidably supported via a sleeve 24. The containers are sandwiched by the open surfaces of the boxes 21 and 22 so as to surround the stoppered cap 11 already installed on the upper edge of the container 10 described with reference to FIG. 22 can be opened and closed by the power in the direction of the arrow 26 acting on the pin 25.

  As shown in the plan view cross section of FIG. 1, sandwiching bodies 29 are fixed to the piston lots 28 of the fluid cylinders 27 individually provided in the two boxes 21 and 22, respectively. Both the sandwiching bodies 29 are made of an elastic material such as rubber attached to the base 30. At both ends of these elastic materials, the pressurizing knobs 31 project at the same intervals as the lengths of both ends of the boat-shaped base 14 already described. To form.

    A vacuum line 33 connected to the box 22 on the one side is connected to a vacuum pump 35 via a three-position / three-port switching control valve 34, and a transmission circuit 38 of a sensor 39 installed in the box is used as an inspection device. 40, while the control valve 34 is provided with a close position 36 at an intermediate position, and when the vacuum line 33 is connected to the close position 36, the air suction in the boxes 21 and 22 is completely stopped. is there.

  In FIG. 3, the holding range of the container 10 by the chamber is a region indicated by an imaginary line 41. As shown in FIG. 1, when the two boxes 21 and 22 of the chamber surround the stopper 14 of the container 10 from both sides, Both the cylinders 27 push out the clamping body 29, and the film constituting the container is clamped and adhered to both end portions of the boat-shaped pedestal 14 by the pressurizing ridges 31 at both ends, and air suction in the chamber 20 is immediately started by the vacuum pump 35. To do.

  As shown in FIG. 2, the container 10 has a relationship in which a boat-shaped pedestal 14 is interposed therein, and therefore there is a space where air exists in the container 10, and therefore, a differential pressure is generated simultaneously with air suction in the chamber 20. The container 10 is expanded and deformed as indicated by an imaginary line 42 in the chamber. In order to protect the container that may be ruptured by this deformation, as shown in FIG. 4, it is desirable to install a regulating member 43 that suppresses the expansion of the container 10 on the base 30 that supports both the sandwiching bodies 29 on the piston rod 28. .

  In this case, the pinching action of the bag mouth by the both holding bars 29 is an act of preventing air leakage from the pinhole that is likely to occur in the boat-shaped pedestal 14, and for example, the pressure of the residual air in the container 10 is accumulated by a timer. The control valve 34 is switched to the intermediate close position 36 at a timing when a predetermined pressure difference is generated between the value and the vacuum value in the chamber 20. If there is a pinhole at both ends of the pedestal 14, the residual air inside the container 10 is ejected from the pinhole into the chamber 20 due to the differential pressure, and as shown in FIG. The pressure P1 changes suddenly as P2, and this change is transmitted to the inspection device 40 by the sensor 39 using the vacuum gauge, so an alarm signal is transmitted from the inspection device. It is. Note that the above-mentioned alarm signal refers to displaying or notifying leakage such as voice and other electrical signals.

  In FIG. 5, the measurement of the pressure change P2 of the chamber is illustrated so as to be performed in an environment of a complete vacuum of 0 Mps on the gauge, but it is not always possible to catch the change in the condition even in such a high vacuum environment. The efficiency is improved by implementing it in an environment close to the limit.

  In order to bring the sharp end of the boat-shaped base 14 in FIG. 7 into close contact with the films 12 and 13, the opposing sandwiching body 50 was formed by a roller having surface lines with small intervals. When both the sandwiching bodies 50 are brought close to each other, both rollers roll on the slopes of the pedestal 14, and one of the convex portions on the surfaces of the both rollers presses the films 12 and 13 against the tip of the pedestal 14 and is expected to crush the pinhole. it can.

In FIG. 1, when the pressure in the chamber 20 is lowered, pressure leakage from the cylinder 27 occurs in the clearance between the slide surfaces of the piston rods 28 of both cylinders 27 and the boxes 21 and 22, which is used for pressure measurement. In the case of influence, the holding body 29 is supported on each of the two balloons arranged in the chamber 20, and compressed air is supplied into the balloons from outside to bring together a pair of opposing holding bodies 29. It is preferable that the pressure of both the balloons 29 is eliminated by releasing the compressed air of both the balloons at the same time that the vacuum is reached.

  Alternatively, the clamping body 29 can be operated using an electromagnetic machine such as a solenoid that does not use pneumatic power as power.

The sensor 39 other than the sensor that measures the pressure change as described above may be a sensor for fluorescence analysis, that is, a sensor that reacts air molecules or gas molecules with fluorescence to measure the residual gas concentration. .

  FIG. 8 shows a cap 11 with a lid that is transported in the direction of an arrow 50 while folding a strip-like film 12 and 13 along the longitudinal direction, and is inserted between the two folded films at equal intervals. , 13 are welded 51 to form a film into a tube, and a tube nozzle 52 disposed in the film is filled with an object to be packaged such as a liquid or powder in the tube film 53, while each is sealed with a cross sealer. This is a bag making apparatus for separating and forming a package, and in such an efficient apparatus, in order to enable a leak inspection efficiently, a simplified diagram is performed by simultaneously surrounding a large number of plugs 11 in a chamber indicated by a virtual line 55. It is.

  That is, as shown in a plan view in FIG. 9, four small chambers 20 are arranged in a column in the region indicated by the virtual line 55. Each of these chambers is shown in FIG. 10 and has already been described with reference to FIG. 1. Each of the chambers 29 is operated by a cylinder 27, a vacuum pump 35 is provided with a switching control valve 34 and a large-capacity tank 56. A sensor 39 for connecting the device 40 is disposed, and each chamber composed of a pair of boxes 21 and 22 surrounds the cap 11 with the lid and moves integrally with the films 12 and 13 and then surrounds each subsequent plug. Therefore, it is configured to retreat. In addition, the upper and lower boxes 21 and 22 may perform a rotary motion that rotates an elliptical orbit in addition to the reciprocating motion described above, and these are defined as circulation as a concept of terms.

  The definition of the term folded film includes an embodiment in which a tube is formed by two layers of films 12 and 13 as shown in FIG. This embodiment shows a case where a self-supporting bag provided with a cap 11 with a lid is formed, and is an example in which a folded base material 60 is interposed between folded films 12 and 13.

  The inspection object can be applied with a sensor to sense the conductivity of the filling liquid blown out from the pinhole of the package.

Plan view sectional view of a small chamber Cross section of side view of previous figure Perspective view of package with stopper Another embodiment showing a partial cross section of the lower region of the small chamber Pressure action diagram for leak inspection Pressure action diagram of leak test by conventional example Another embodiment of the clamp Explanatory drawing of 2nd Example Plan view of the previous figure Front view of the previous figure Other examples of tube formation

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Packaging 11 ... Lid 12, 13 ... Folded film 14 ... Boat-shaped base 20 ... Small chamber 21, 22 ... Box 29 ... Holding body 30 ... Base 33 ... Vacuum line 34 ... Switching control valve 35 ... Vacuum pump 39 ... Sensor 40. Inspection equipment

Claims (3)

A method for inspecting leakage of a packaging container with a cap formed by inserting a boat-shaped pedestal portion of a cap with a lid between two folded films and welding the two-folded film edge to the boat-shaped pedestal. The film edge is sandwiched between a pair of small chambers so as to surround the stopper, and both ends of the boat-shaped pedestal are concentrated in the chamber while being pinched by a sandwiching body from the outside of the film. A method in which, after forcibly sucking in the air, the air suction is stopped, and simultaneously with the opening of the clamping bar, a pressure change in the chamber is detected by a sensor. A device for inspecting leakage of a packaging container with a cap formed by inserting a boat-shaped pedestal portion of a cap with a lid between two folded films and welding the edge of the two folded films to the boat-shaped pedestal. A pair of small chambers hermetically surrounding the periphery of the stopper, a sandwiching body for squeezing and releasing the both ends of the boat-shaped base in the chamber from the outside of the film, and the sandwiching body Means for forcibly sucking the air in the chamber in accordance with the clamping action on the film by the sensor, a sensor for detecting the pressure change in the chamber in response to the stop of the air suction, and depending on the pressure change A device comprising means for issuing an alarm. While the film is folded in half and transported in the longitudinal direction, a plurality of lidded caps are supplied between the two folded films at equal intervals corresponding to the transporting operation of the film, and the folded film edge Is a leakage inspection device for a bag-making apparatus that continuously welds the caps to the boat-shaped bases of the caps with caps to continuously form the tubes with the caps. A plurality of small chambers, means for advancing and circulating each of the small chambers in accordance with the transporting operation of the film, and concentrating both ends of the boat-shaped pedestal in the chambers, from the outside of the film. Corresponding to the holding body for clamping and releasing, means for forcibly sucking the air in the chamber according to the clamping action to the film by the clamping body, and stopping the air suction A sensor for detecting serial pressure changes small chamber, respectively, and means for issuing an alarm in response to the pressure changes in the device.