JP2908751B2 - Inspection method of sealed package - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for inspecting pinholes in a completely sealed package such as food or medical consumables.

[0002]

2. Description of the Related Art Hermetic packaging is now used for many products other than medical consumables such as food and physiological saline in order to maintain the sterility of the contents. However, because the contents of the package come into contact with the atmosphere and cause deterioration and decay, and in the case of medical consumables, for example, infusion bottles, they can cause contamination and deterioration. Very important. Conventionally, as this pinhole inspection method, in the case of foods, a metal pin is pierced into a completed package and this is used as one of the electrodes, and the package is brought into contact with the package because an electrode cannot be put in a sealed package. As a counter electrode of the external electrode, a pinhole was inspected by applying a high voltage between the two electrodes, and the pinhole was sealed in a separate process after the inspection, but the inspection process was complicated and the pinhole was closed. There was a drawback that required a process. In order to eliminate this drawback and perform a pinhole inspection without damaging the completed sealed package, for example, as shown in Japanese Patent Publication No. 50-6998, food is sandwiched between a pair of electrodes. A voltage is applied between both electrodes with a large difference in capacitance formed between each electrode and the food, and a pinhole is detected by detecting a current caused by a flash between one electrode and the food. There is something like that.

[0003]

As described above, when detecting the presence or absence of a pinhole by detecting the current caused by a flash, on the actual work surface, the presence or absence of the pinhole is determined by a change (large or small) in the detected current. I try to detect. In this case, it is determined that there is no pinhole due to an error in the current at the detection unit due to the influence of the humidity and temperature of the outer periphery of the test object, which forms the atmosphere at the time of inspection, and fine dust floating. It was inevitable that malfunctions would occur.

[0004] The present invention has been made in view of the above points, and a sealed package in which contents such as a fluid, a powder, or food having conductivity are covered with an electrically insulating film is provided as a pair. When pinhole inspection is performed by sandwiching between electrodes and applying a high voltage,
An object of the present invention is to provide a method for inspecting a sealed package in which occurrence of a malfunction due to an atmosphere during the inspection is completely prevented.

[0005] In this case, the sealed package to be inspected is mainly a food, mainly a cylindrical package in which sausages are sealed and packaged one by one, as well as a flat bag made of a plastic film. Retort foods,
As medical consumables, the inspection target is to prevent contamination and alteration of the contents based on contact with the outside air due to pinholes. In addition to infusions such as physiological saline and Ringer's solution in thin plastic infusion bottles, as well as thin plastic Blood products such as blood transfusion and plasma in a bag are included. Furthermore, a sealed package in which a powdered conductive material such as iron powder, which is a solid material, is sealed in a thin plastic bag can also be inspected.

[0006]

In order to achieve the above object, in the method for inspecting a sealed package according to the present invention, a conductive fluid, powder, food or other content 1 is electrically insulated. 2 is placed on a supporting electrode 4 of a predetermined shape such as a grounded electrode plate or the like.
3 _{while 1} contacting the placing in, by applying a high DC voltage between the electrode 5 brought into close contact with or close face to the subject end 3a of the sealed package 3 and the support electrode 4, the test end When there is a pinhole in the portion, the contents 1 are charged through the pinhole, then the grounding of the support electrode 4 is released, and the electrode 5 contacted with the test end 3a is grounded,
A method of detecting a pinhole in the sealed package 3 by detecting a discharge current from the test end 3a is adopted.

As a result, the test end 3a of the sealed package 3
In the case where there is a pinhole, the test end 3a of the sealed package 3
The applied high DC voltage between the supporting electrode 4 in intimate or contact with the side surface portion 3 ₁ of the electrode 5 was allowed proximate facing sealing package 3, the the contents of the first sealing package through the pin holes, Via the electrically insulating film 2 in contact with the support electrode 4, positive (+) ions are generated and charged with respect to the negative (-) charge of the grounded support electrode. When the test end 3a and the electrode 5 face each other, the electrode 5
A flash due to a high DC voltage is generated between the terminal and the pinhole at the end of the test object, and the contents 1 of the sealed package are charged.

Next, the grounding of the support electrode 4 is released, and the electrode 5 contacted with the end 3a is detected.
(If the test end 3a and the electrode 5 are close to each other, they are brought into contact with each other.) Then, the electric charge charged in the contents 1 is discharged, and the discharge current is detected. The pinhole at 3a is detected.

At this time, irrespective of the atmosphere at the time of inspection, if there is no pinhole in the inspected portion, the contents 1 will not be charged at all,
Since the charging is performed when the pinhole is present, the presence or absence of the pinhole at the test end portion 3a (the location where the pinhole is most likely to occur) can be reliably detected without error.

The electrode 5 is closely attached to the end 3a to be inspected.
A conductive rubber formed to be attachable can be used. That is, when the test end portion 3a uses a mass-produced molded product or the like, the shape of the electrode 5 is maintained by using the elasticity of the conductive rubber because the shape is kept constant or almost constant. Can be easily attached closely to the surface of the test end portion to obtain conduction.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a plastic film or a thin plastic corresponding to the contents is used as an electrically insulating film 2 for covering the contents 1 of a sealed package 3 to be inspected. That is, when the content 1 is, for example, fish sausage, a bag made of a vinylidene chloride film is used, and after filling the fish meat sausage surimi, both ends are clipped with an aluminum wire, and retort sterilization is performed. In addition, even a retort food using a bag of a composite film (laminated film) containing no aluminum foil in the inner layer can be a target of a sealed package to be inspected. In this case, a bag of a composite film of nylon and polypropylene or polyester and polypropylene, or polyester and vinylidene chloride and polypropylene is used. On the other hand, in the case of infusion such as physiological saline and Ringer's solution, predetermined thin plastic infusion bottles are used. Furthermore, as the fluid having conductivity, solid fluid, for example, conductive powder such as iron powder can be used as the content 1.

The support electrode 4 on which the sealed package 3 is placed has:
A side surface portion 3 ₁ for placing the hermetically sealed package 3 on the supporting electrode 4 and making contact therewith.
Depending on the form, the support electrode 4 is a plate-like electrode, or an electrode in which a large number of small-diameter rollers are arranged adjacent to each other and the contact surface of the upper surface is arranged in a plane. However, an electrode having an arbitrary shape such as an arc-shaped electrode can be used. After charging the contents 1, the grounding of the support electrode 4 is released, or the sealed package 3 is supported by an insulator. A metal electrode can be used for the electrode 5 that is brought into close or close proximity to the test end portion 3a, and a conductive rubber (porous conductive rubber) or a conductive plastic formed so as to be in close contact is used. It is also possible. Furthermore, in detecting the discharge current from the test end 3a,
A current transformer (CT) of a type in which a detection unit is wound around a conductor through which a discharge current flows and a current detector in series with the conductor can also be used.

[0013]

【Example】

[Embodiment 1] FIG. 1 shows a case where the sealed package 3 is an infusion bottle for drip in which physiological saline is sealed. The transfusion bottle 3 has a cross section of a main body formed of a slightly thick film 2 of plastic.
A rectangular section with a radius of 65 mm x 90 mm and a radius of 240 mm has a height of 240 mm and a capacity of 1000 ml. The test end 3a where a pinhole is easily formed is an opening at the step end with an external shape of 28 mm and a thickness of 8 mm. A rubber plug portion 3b for inserting a drip needle is provided in the airtight portion, and a suspension ring portion is provided on the opposite side. In the test end portion 3a, a pinhole or a place where a gap corresponding to the pinhole is likely to be formed is a peripheral edge of a ring-shaped step portion holding the rubber plug portion 3b, and an opening of the step portion holding the rubber plug portion 3b. It is a boundary portion between the section and the rubber plug section 3b.

[0014] In order to pinhole inspection of the test end 3a of the transfusion bottle 3, first, an electrode 5 brought into close contact to said Kentan portion 3a, contacted placing the side surface portion 3 ₁ of the transfusion bottle 3 A high DC voltage is applied between the support electrode 4 and the support electrode 4. The electrode 5 to be allowed to close to said Kentan portion 3a, 2 two split portions 5 _1, 5 ₁ and the metal ring portion made of the rubber stopper portion 3b front and fitted into the ring portion having a predetermined cross-sectional shape a metal-made tablet portion 5 ₂ which predetermined cross-section formed as closely to,
This is used by closely contacting the side of the test end 3a from the front.

On the other hand, the support electrode 4 on which the infusion bottle 3 is placed is
Those of a flat predetermined size for supporting the side surface portion 3 ₁ entire transfusion bottle 3, negative DC high voltage power supply 6 with grounding the lower portion of the electrode 4 via a line - connects to side (). The electrode 5 closely contacted with the test end 3a is connected to the positive (+) side of the DC high-voltage power supply 6, and a predetermined DC high voltage (0.6 to 30 kV) is applied between the electrode 5 and the support electrode 4. ) Is applied.
As a result, the content 1 is charged only to the object end 3a having a pinhole or a gap corresponding to the pinhole.

Next, the supporting electrode 4 on which the sealed package 3 is placed
Is released 4 'or transferred to a support electrode 4' made of an insulating material. Then, the connection on the positive (+) side of the DC high-voltage power supply to the electrode 5 on the test end portion 3a side is released, and the conductor 8 from the electrode 5 is grounded. The conductor 8 is provided with a discharge current detector 7 including a current detector 7a surrounding the conductor 8 in order to detect a current flowing through the conductor 8. A predetermined current transformer (C
T: current transformer) is used, but a current detector in series between the electrode 5 and the ground may be used for current detection.

When a pinhole is present at the test end 3a, the discharge current flows through the conductor 8 because the contents 1 of the sealed package 3 are charged.
Is detected, but when there is no pinhole, the contents 1 are not charged and the discharge current does not flow through the conducting wire 8, so that the discharge current detecting device 7 does not detect this. Therefore, the presence or absence of a pinhole in the test end 3a can be easily known by displaying the current detection output on a suitable display means such as a meter, a warning buzzer, or a warning lamp.

[Embodiment 2] FIG. 2 shows a case where the test end 3a of the sealed package 3 is a binding portion of a bag in which the contents 1 are sealed with the electrically insulating film 2, and the test object is subjected to direct current. The case where a high voltage is applied is shown. In this case, pinholes generated in the electrically insulating film 2 are concentrated near the test end 3a. The contents 1 are, for example, fish meat sausages, and the electric insulating film 2 is made of a single film of vinylidene chloride which is transparent and has excellent shrinkage and barrier properties. ing. Support electrode 4 on which the sensor is placed
Is a metal plate having an arc-shaped inner surface corresponding to the object to be inspected, and the electrodes 5, 5 to be brought into close contact with the ends 3a, 3a at both ends which are the binding portions are each made of a porous conductive material. A concave portion made of rubber and capable of accommodating the test end portion 3a is provided on one side of the center, and when the test end portion 3a is pushed into the test end portion 3a, the test end portion 3a
It is formed in a cap shape so as to be in close contact. The support electrode 4 is grounded, and the negative (−) side of the DC high-voltage power supply 6 is connected to the support electrode 4. A pair of cap-shaped electrodes 5, 5 at both ends of the test object are connected to the positive (+) of the DC high-voltage power supply 6.
Side, and a high DC voltage of 0.6 Kv to 30 kv is applied between the supporting electrode 4 and the electrodes 5 and 5 over the test end 3a as in the first embodiment. As a result, when there is a pinhole at both ends 3a, 3a of the sealed package 3 to be tested, the contents 1 are charged, so that the grounding of the support electrode 4 is released as in the previous embodiment, The connection is transferred to a supporting electrode made of an insulating material, and the connection of the conducting wire 8 from the pair of electrodes 5 and 5 on the positive (+) side of the DC high-voltage power supply 6 is released to ground it. And
A discharge current flowing through the conductor 8 is detected by a discharge current detection device 7 such as a current transformer (CT) in the same manner as in the first embodiment,
The presence or absence of the pin current in the sealed package 3 can be detected based on the presence or absence of the discharge current.

[Embodiment 3] FIG. 3 shows a case of inspecting a hermetically sealed package 3 such as a retort food or the like whose end 3a is a heat seal portion of a plastic film bag. In these hermetically sealed packages, pinholes generated in the electrically insulating film concentrate near the test end portion 3a, which is a heat seal portion. The content 1 is a packaged food such as a retort food, and the electric insulating film 2 is the composite plastic film (laminate film) containing no aluminum foil in the inner layer. The plate is placed on a flat support electrode 4 corresponding to the size of the test object.
Is grounded via a conductor and connected to the negative (-) side of the DC high-voltage power supply 6. The electrode 5 to be brought into close contact with the test end 3a is provided with a slit of a predetermined shape capable of holding the test end 3a on one central surface made of porous conductive rubber.
Open both sides of the slit and insert it so as to sandwich the test end 3a. The test ends 3a, 3a, which are heat seal portions on both sides of the package 3 to be tested, are tightly held by the electrodes 5 and connected to the positive (+) side of the DC high-voltage power supply 6 to be connected to the support electrode 4 and the test target. A high DC voltage of 0.6 kv to 30 kv is applied between the electrodes 5 and 5 which are brought into close contact with the end 3a in the same manner as in the above embodiment. Thereafter, the grounding of the support electrode 4 is released, or the support electrode 4 is moved to a support electrode made of an insulating material, and the connection of the conductor 8 from the pair of electrodes 5 and 5 to the positive (+) side of the DC high-voltage power supply 6 is released. Is grounded, and the discharge current flowing through the grounded conductor 8 is detected by a discharge current detection device in the same manner as in the above embodiment. By detecting the discharge current, it is possible to detect the presence / absence of a pinhole near the heat-sealed portion of the hermetically sealed package 3 where the pinhole is most likely to occur.

As described above, the sealed package to be inspected is charged,
When inspecting by detecting the discharge current, charging is impossible unless there is a pinhole in the sealed package to be inspected. It is possible to completely prevent an inspection error due to an atmosphere at the time of the inspection without making a mistake as in the above. In the above embodiment, when a high DC voltage is applied to the test sealed package, the support electrode side is set to minus (-) and the electrode at the test end is set to plus (+). Depending on the contents of the package, the application directions of (+) and (−) can be reversed.

In addition to the above-described embodiment, the method for inspecting a sealed package according to the present invention can be similarly applied to ampoules of an injection solution or a swallow. For example, a main body of an ampule is placed on a support electrode having an arc-shaped inner surface, and an electrode is placed on the tip of the ampule including a neck portion where a pinhole is likely to occur, and a DC voltage is applied between the electrode and the support electrode. After applying a voltage, it can detect the discharge current from the ampoule and inspect pinholes, so it has a wide range of applications.

[0022]

According to the method for inspecting a sealed package according to the first aspect of the present invention, a sealed package in which a conductive fluid, a powder, or a food or the like is covered with an electrically insulating film. When inspecting the pinhole, the sealed package to be inspected is charged only when the inspected portion has the pinhole, and by detecting the discharge current, the pinhole is detected.
As in the past, when a high voltage is applied to the test object and the pin current is detected by the current flowing, the malfunction is completely prevented without being affected by the humidity or the atmosphere at the time of the test. The presence of the pinhole in the hermetically sealed package can be efficiently inspected together with the inspection of the test end portion at the site where the pinhole occurs. When a high voltage is applied to a large number of specimens for inspection, only charged specimens are detected as pinholes. Normally, only a small number of charged specimens are charged. Is small, so the risk of inspection is low and the safety is high.

According to the second aspect of the present invention, when the shape of the end of the hermetically sealed package where the pinhole is most generated is constant or almost constant in a mass-produced product, it is closely attached to the end to be inspected.
An electrode made of conductive rubber, which is formed as possible, can be closely attached to the test end portion by utilizing its elasticity, and the inspection of the sealed package can be easily performed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an inspection method of the present invention when a sealed package is an infusion bottle such as a physiological saline solution.

FIG. 2 is a configuration diagram showing a previous stage of the inspection method of the present invention when the sealed package is sausages whose ends are tied.

FIG. 3 is a configuration diagram showing a preceding stage of the inspection method of the present invention when the sealed package is a heat-sealed bagged food such as a retort food.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Contents, 2 ... Electric insulation film, 3 ... Sealed package, 3a ... Test end part, 4 ... Support electrode, 5 ... Electrode.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) G01N 27/00-27/24 G01N 27/92 G01M 3/40

Claims (2)

(57) [Claims] 1. A sealed package 3 in which a content 1 such as a fluid, powder or food having conductivity is covered with an electrically insulating film 2.
And while placed in contact with the side surface portion 3 ₁ of the sealed package 3 on the support electrode 4 having a predetermined shape of the electrode plate or the like which is grounded, close or close to the subject end 3a of the sealed package 3 A high DC voltage is applied between the facing electrode 5 and the support electrode 4 to charge the contents 1 through the pinhole when the pin end is present at the test end. The grounding is released, and the electrode 5 contacted with the test end 3a is grounded, and the discharge current from the test end 3a is detected to detect the pinhole of the sealed package 3. Inspection method of sealed package. 2. An electrode according to claim 1, wherein said electrode is a conductive rubber formed so as to be able to be closely attached to said end portion to be inspected.
Inspection method of the sealed package described.