JPS6026451B2 - Inspection method for pinholes in sealed packaging - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to vaporizable substances such as glucose injection, distilled water for injection, milk, and oil, and sublimable substances such as naphthalene (in this specification, these are referred to as vaporizable substances). It is called.

) in a sealed package made of synthetic resin, paper, metal, etc., for the presence or absence of pinholes (pinholes, cracks, etc.). Conventionally, there has been a vacuum pinhole presence test as a method for inspecting the presence of pinholes in sealed packages of this type. It has been mainly used.

In this vacuum pinhole presence test, the sealed package is placed in an airtight inspection chamber, and after the inspection chamber is evacuated to a predetermined vacuum state, vacuum suction is shut off or stopped.
After that, the pressure rise in the test chamber is measured, and if the pressure rise value is higher than a predetermined reference value, the contents of the package are vaporized from there because there is a pinhole in the sealed package (vaporization is not defined as "vaporization" in this specification). The vaporizable substance changes from a liquid state to vapor or gas, or sublimates from a solid state.

), and it was determined that there was a pinhole when the pressure increase occurred, and when the pressure increase value was 4 points lower than the reference value, it was determined that there was no pinhole. However, during the inspection, there is no means for effectively removing the substances that flowed into the inspection chamber from the pinholes of the package having pinholes, and the substances that remained in this way are During the next test, it vaporizes under vacuum again and acts as a disturbance (noise), causing pinholes in the sealed package during the next test. There is a drawback that it may be incorrectly determined that there is a pinhole, and when the standard value is set to a large value in order to avoid such a misjudgment, there is a possibility that a package with a pinhole will be incorrectly determined as having no pinhole due to dust. . Furthermore, apart from the fact that the substance that has flowed out from the pinhole remains attached to the inspection room, if the vaporized substance has adhered to the surface of the sealed package for some reason before the inspection, the vaporized substance will also be vaporized during the inspection. In this case as well, a sealed package without pinholes may be mistakenly determined to have a pinhole, and the substance that has flowed out from the surface of the sealed package may still remain in the inspection chamber and be used for the next inspection. It has the disadvantage that it sometimes acts as a disturbance. In addition, in order to sufficiently remove the volatile substances remaining in the examination room after a test in preparation for the next test, the examination room must be vacuumed for a long time, which makes the test inefficient. Ta.

An object of the present invention is to promptly collect vaporized substances adhering to the inspection chamber or the surface of a sealed package in the inspection chamber when inspecting for the presence of pinholes, and to detect the presence of pinholes under virtually no disturbance. An object of the present invention is to provide a method for inspecting the presence or absence of pinholes in a sealed package, which can accurately determine the presence or absence of pinholes in a sealed package.

In accordance with the above object, the present invention provides a method for inspecting the presence of pinholes in a sealed package in which a vaporizable substance is sealed, in which the sealed package is placed in a test chamber, the test chamber is made airtight, and the interior of the test chamber is sealed. A vaporizing vacuum suction device connected to the chamber is used to evacuate the vaporizable substance adhering to the inspection chamber and the surface of the sealed package, and the vaporized substance is transferred to a cooling heat installed in the inspection chamber. After substantially removing the vaporized substances adhering to the inspection chamber and the surface of the sealed package by cooling and collecting them in an exchanger, the inspection chamber is isolated from the cooling heat exchanger and the inspection chamber is removed. Create a predetermined vacuum state using the measurement preparation air suction device installed in the examination room.
After that, the vacuum suction in the examination chamber is shut off and the pressure increase due to vaporization in the examination chamber is measured. If the pressure increase value is above a predetermined standard pressure value, there is a pinhole, and if it is smaller than the standard pressure value, there is a pinhole. The step of determining that there is no hole and vaporizing the vaporizable substance adhering to the inspection chamber and the surface of the sealed package, and the step of measuring the pressure increase in the inspection chamber, at least the step of A method for inspecting the presence or absence of pinholes in a sealed package, characterized in that in the step of vaporizing the vaporizable substance adhering to the inspection chamber and the surface of the sealed package, the location of the sealed package is heated.

Such a method includes a device for inspecting the presence of pinholes in a sealed package in which a vaporizable substance is sealed, an inspection chamber equipped with an inlet and an outlet of the sealed package, a first diamond-shaped device capable of airtightly closing the inlet; a second lid device capable of airtightly closing the outlet;
a vaporizing vacuum suction device for vaporizing vaporizable substances in the examination chamber; and a cooling heat exchanger installed in the examination chamber so as to be shut off for cooling and recovering the vaporized substances in the examination chamber. a measurement vacuum suction device for evacuating the examination chamber to a predetermined vacuum state and then cutting off vacuum suction in the examination chamber; and a pressure measurement for measuring a pressure increase due to vaporization in the examination chamber after the vacuum suction is stopped. The present invention can be carried out by an apparatus for inspecting the presence or absence of pinholes in a sealed package, which is equipped with a device that can heat the location of the sealed package in the inspection room. In addition, in this specification, "cooling recovery" refers to freezing or liquefying a vaporizable substance and maintaining it in a frozen or liquid state. The above method also includes "an examination chamber having an inlet and an outlet of the sealed package, a first lid device capable of airtightly closing the inlet, and a second lid device capable of airtightly closing the outlet. A plurality of unit bodies are disposed at intervals around a rotationally interlockable support base, and a supply station for sealed packages to be inspected, a discharge station for defective sealed packages, and a station for discharging sealed packages to be inspected are provided in the movement path of the unit bodies. A station for discharging non-defective sealed packages is provided, and the inspection chamber of each front unit is equipped with a vacuum suction device for vaporization to vaporize the vaporizable substances in the inspection chamber, and a vacuum suction device is installed to vacuum the inspection chamber to a predetermined vacuum state. A measuring vacuum suction device for cutting off the vacuum suction in the examination room and a pressure measuring device for measuring the pressure increase due to vaporization in the examination room after the vacuum suction is cut off are connected, and A cooling heat exchanger for cooling and recovering vaporized substances is installed in the lotus system so as to be able to be shut off from the inspection room, and a device is further provided that can heat the portion of each knitted body where the sealed package is placed in the inspection room. The present invention can be carried out more efficiently by the "pinhole presence/absence inspection apparatus for sealed packages" characterized by the following.

The above and other objects, features and advantages of the present invention will become apparent from the following description of embodiments of the invention with reference to the accompanying drawings.

First, an explanation will be given of the example of the apparatus for carrying out the method of the present invention shown in FIGS. The outlet 12 is provided with a first lid device 13 that can be closed off, and a second lid device 14 that can be airtightly closed off.

The first lid device 13 is a lid 13 that is slidably provided with respect to the inlet 11 so as to open or airtightly close the inlet 11.
1 is a type that can be opened and closed by pneumatic means such as a cylinder operated by a solenoid valve (for example, a gate type pneumatic valve VAP type manufactured by Japan Vacuum Technology Co., Ltd.). Of course, other than this, various known automatic or manual devices can be used as the lid device. The second lid device 14 has the same structure as the device 13. A vacuum suction device 2 is connected to the examination chamber 1.

The vaporization vacuum suction device 2 includes a vacuum pump 21 connected to the examination chamber 1 through piping. Between the examination room 1 and the pump 21,
If necessary, a valve for maintenance and inspection (for example, manual valve 20) and a vacuum gauge 22 for checking the operating status of the vacuum suction device 2 can be connected as appropriate. A cold wrap or other cooling heat exchanger 23 can be connected. In the vacuum suction device 2, a plurality (two in the example of the device shown in FIG. 1) of cold traps 31 and 32 for freezing and recovering vaporized substances are arranged in parallel to the circuit of the device 2.

It is desirable that the traps 31 and 32 be placed as close to the examination room 1 as possible so that vaporized substances within the examination room can be efficiently frozen and recovered. The traps 31 and 32 may be replaced by a single trap, but two or more traps may be arranged in parallel as shown in the figure, and the traps may be placed at branch points depending on the capacity of the cold trap, the degree of dryness in the examination room, etc. Either one of the valves (three-way solenoid valve 33 in the case shown) provided
Alternatively, two or more traps can be used selectively or all traps can be used simultaneously at any time. The traps 31 and 32 are detachably arranged so that they can be replaced at any time in case the vaporized substance in the nuclear trap freezes excessively.

However, the traps 31, 32 may also be fixed in the device 2. In that case, a liquid receiver (not shown) or the like is arranged below the traps 31, 32, and when the vaporized substance freezes excessively, the frozen substance can be liquefied and taken out by the receiver. Furthermore, in order to speed up the liquefaction, an appropriate heating device can be attached to the trap. In FIG. 1, hand-held valves 34, 35, 36, and 37 are valves that are closed when replacing the trap.

It goes without saying that these valves and other valves can be automated as appropriate electromagnetic valves. Although the cold traps 31 and 32 are of a type that freezes vaporized substances, they may also be of a type that liquefies them.

However, the type that freezes is preferable. It goes without saying that other cooling heat exchangers having a similar function (a function of freezing or liquefying vaporized substances and cooling and recovering them) can be used in place of the cold trap described above.

Further connected to the examination chamber 1 are a measurement vacuum suction device 4 and a pressure measurement device 5. The vacuum suction device 4 includes a vacuum pump 41 pipe-connected to the examination room 1, an electromagnetic valve 42 connected between the examination room 1 and the pump 41, and a pressure switch 43 for operating the valve 42. When the examination chamber 1 is evacuated to a predetermined vacuum state by the pump 41, the pressure switch 43 is activated to close the valve 42, and the vacuum suction of the examination chamber 1 is stopped or cut off.
In addition, as means for stopping the vacuum suction in the examination room 1 when the examination room 1 reaches a predetermined vacuum state, an appropriate pressure gauge is used instead of the pressure switch 43, and a manual operation is used instead of the electromagnetic valve 42. Any other suitable means may be used, such as using a valve, monitoring the pressure gauge and closing a manual valve. Further, between the inspection chamber 1 and the pump 41, valves for maintenance and inspection, etc., and a vacuum gauge 44 for checking the operating status of the vacuum suction device 4 can be connected as appropriate. A cold trap or other cooling heat exchanger 45 for pump protection can be connected nearby. The pressure measuring device 5 includes a pressure sensor 51 that is connected to a pipe from the testing room between the vacuum suction stop valve 42 and the testing room 1, and detects a pressure increase in the room 1 and converts it into an electric current, and an amplifier 52 for amplifying the input of
It displays the input from the amplifier 52, stores a predetermined reference value for pinhole presence determination, and outputs a signal indicating whether the input from the amplifier is greater than or equal to the reference value. It is provided with a meter relay 53 and a display 54 that displays whether there is a pinhole or not according to the input from the meter relay 53.

Therefore, the presence or absence of a pinhole can be determined by monitoring the meter relay 53 by an operator who has memorized the reference value, or by simply checking the display 54. Note that the display 54 may be provided with a display section that receives a signal from the pressure switch 43 and indicates whether or not an inspection is being performed (in other words, indicates whether the solenoid valve 42 is opened or closed).

In addition, the display 54 automatically controls the solenoid valves appropriately installed in the vacuum suction device, the solenoid valves of the lid devices 13 and 14, etc. in response to the signal from the meter relay 53 or amplifier 52 and/or the signal from the pressure switch 43. By incorporating a controller, the inspection process can be automated. As the pressure measuring device, a simple pressure gauge or other appropriate means may be used instead of the structure of the device described above.

Note that valves 38 and 46 are provided to close the device 4 when the device 2 is in use, and to close the device 2 while the device 4 is in use.

The valves 38 and 46 can also be automated as electromagnetic valves. The inspection room 1 is further provided with a device 15 for heating the location B of the package A.

The heating device 15 may include an electric heating plate 151 (see FIG. 3) surrounding the region B, as well as a steam tube or an infrared heater (not shown). These electric heating plates 151 and steam pipes,
It is desirable that the infrared heater is surrounded on the outside by a heat insulating material 152 so as not to radiate unnecessary heat into the room 1. As the heating device, in addition to the above, a high frequency heating device as shown in FIG. 4 can also be used. In FIG. 4, 153 is a high frequency oscillator, 154 is a waveguide, and 155 is an applicator. Next, an example of the method of the present invention using the apparatus shown in FIG. 1 will be explained.

The exit 12 of the inspection chamber 1 is closed by the lid device 14, the inlet 11 is opened by the lid device 13, the sealed package A to be inspected is placed in the chamber 1 from this entrance, and then the entrance 11 is closed. Make room 1 airtight.

Further, the valve 38 of the vacuum suction device 2 is opened, and the valve 46 of the vacuum suction device 4 is closed. After that, the inside of the examination chamber 1 is evacuated using the vacuum suction device 2 for vaporization, and the vaporizable substances adhering to the surface of the package A (and the vaporizable substances adhering to the inside of the chamber 1) are vaporized. The collected substances are cooled and collected in cold traps 31 and 32 arranged in the apparatus 2, and the vaporizable substances on the surface of the package A (and the vaporizable substances if they are attached inside the room) are substantially removed. In the above step, the arrangement part B of the package A (therefore, the surface part of the package A, etc.) is heated by the heating device 15 to promote the vaporization of the vaporizable substance adhering to the surface of the package A, thereby Aim to streamline and speed up the entire inspection process.

In order to promote the above vaporization, it is sufficient to increase the degree of vacuum in the examination room 1, but when the degree of vacuum reaches a certain point, the package A
Volatile substances on surfaces, etc. remain in a frozen state unless heat is applied from the outside, and from then on, no matter how much the degree of vacuum is increased, the temperature of the frozen object will only decrease, and the equilibrium vapor pressure of the frozen object corresponding to that temperature will decrease. Only the sublimation pressure is maintained, and the qi○ phenomenon is virtually not observed.

Therefore, by heating the placement part of package A, this equilibrium state is broken and the difference between the temperature of the surface of part B or package A and the temperature of the cold trap is increased, and the driving force for vaporizing and eliminating the vaporizable substance is increased. This increases the For example, if distilled water in the package A flows out from a pinhole and adheres to the surface of the package A in this embodiment, unless the package A is heated, the attached water will be approximately 4.57 torr. It turns into ice at a vacuum level of , and virtually no water vapor is generated even if the vacuum level is increased thereafter.

Therefore, in order to promote the evaporation of attached water, when trying to maintain the inside of the examination room 1 at approximately 9.66 x 10-2 Torr (-40°C ice), the surface of the package A should be kept at a temperature higher than 0°C. If energy corresponding to the shaded area C in FIG. 5 (attached water-energy diagram) is added as latent heat so as to maintain the temperature, the evaporation and removal of the attached water will be promoted. The generated water vapor is captured in a cold trap where its heat is absorbed. Generally, when the deposit on the surface of the package is something like an injection liquid that has flowed out from the package through a pinhole, the surface of the package A is approximately zero.
It may be heated to maintain the temperature between ℃ or higher and around room temperature.

In any case, the material inside the package should not be heated to such an extent that the quality of the material is degraded. Next, the valve 38 is closed and the valve 46 is opened. After that, the measurement vacuum suction device 4 brings the inside of the examination chamber 1 into a predetermined vacuum state, and then the vacuum suction in the examination chamber 1 is stopped or cut off.

Thereafter, the pressure increase due to vaporization in the examination chamber 1 is measured by the pressure measuring device 5, and if the pressure increase value is greater than a preset reference value for determining the presence or absence of a pinhole, it is determined that there is a pinhole, and if it is small, it is determined that there is no pinhole. judge. After the above determination, the exit 12 of the inspection chamber 1 is opened to allow the package A after inspection to fall outside the room.

In order to measure the pressure increase due to vaporization of the substance inside the package through the pinhole of the sealed package A in the above-mentioned inspection room 1, in order to promote the vaporization, the package placement site in the inspection room 1 [
Therefore, the heating device 15 can also heat the package A] placed in the area.

Such heating is performed when the pinhole in package A is 4 poles.
It is therefore advantageous when it is desired to increase the degree of vacuum in the examination room. After the above inspection is completed, the outlet 12 is closed again to make the inspector 1 airtight, the valve 46 is closed, and the valve 38 is opened.
Vaporization vacuum suction device 2 and cold traps 31, 32
It is desirable to cool and recover the vaporized substances that flowed out from the pinholes of package A and remained inside the room during the above inspection in preparation for the next inspection.

In order to accelerate the vaporization of the residue in the second chamber, the heating device 15 can heat the portion of the package A where the residue mainly resides.

Of course, the vaporization and measurement vacuum suction devices may each use the other's vacuum suction circuit, vacuum pump, etc. as its own circuit, vacuum pump, etc.

However, for example, when a vacuum suction device for vaporization is used as a vacuum suction device for measurement, it is naturally desirable to connect the pressure measurement device at a position closer to the examination room than the cold trap disposed in the vacuum suction device for vaporization. Next, a description will be given of a device that can perform a pinhole presence inspection more efficiently than the above-mentioned method.

FIG. 2 schematically shows a plan view of a portion of this example device.

That is, a plurality of unit bodies 10 consisting of an examination chamber 1 having the same configuration as in the apparatus shown in FIG. 1 and first and second lid devices 13 and 14 are capable of intermittent rotational movement by a known intermittent rotation drive device (not shown). A feeding station 102 for package A, a defective sealed package discharging station 103 and a good sealed package discharging station 104 are arranged at intervals around the support base 101 of the unit body 10, and in the movement path of the unit body 10,
is provided.

In the examination chamber 1 of each unit body 10, a vacuum suction device 2 for vaporization similar to that in the device shown in FIG. (not shown in Figure 2). Furthermore, unit body 1
A measuring vacuum suction device 4 and a pressure measuring device 5 similar to those in the apparatus shown in FIG. 1 are connected to the inspection chamber 1 of No. 0 (not shown in FIG. 2). Further, the inspection room 1 is provided with a diamond plate 15 that can heat the area where the sealed package is placed. The vacuum suction device 2, 4 and the cold trap 31,
32 and the pressure measuring device 5, for example, the rotating support base 101.
placed on top.

Each of the above-mentioned vacuum suction rhombuses, each set of cold traps, and each pressure measuring device may be provided one by one in each unit body 10, but one or two or more may be provided in each unit body 101. However, it goes without saying that they may be connected so that they can be shared as appropriate.

Note that when it is desirable to discharge the package A having a clearly large pinhole at a stage before the station 103, the discharge station 105 for the package A having a large pinhole is placed between the supply station 102 and the discharge station 103. may be provided. A coupling device 106 connected to the production line L of the packaging body A is provided at the supply station 102 as needed.

The supply device 106 distributes and arranges the packages A sent in a line from the line L to the feeding end of a conveyor 1061 serving as a lot station in order to collect the packages A into a lot A' consisting of a plurality of packages A. A device 1062 and a stopper device 10 that stops the package A in the middle of the conveyor 1061 until a predetermined lot of packages is completed.
63, and lot A' that came out from the stopper device 1063.
A device 1064 is provided for pushing out the liquid to the entrance of the examination room of the unit body 10 disposed in the station 102. The sorting device 1062 includes a rotating arm 106 in which the package A has a passage 1062a, one end of which is rotatably attached to the delivery end of the line L, and the other end of which faces the conveyor 1061.
2A, and an appropriate driving means (not shown) for rotating this arm so as to sort the packages. The stopper device 1063 detects whether or not a predetermined number of packages A has reached the stopper 1063a that can be raised and lowered into the rod A' passage by a drive means (not shown) and this stopper, and raises the stopper when a predetermined number of packages A has arrived. for phototube switch,
It is equipped with appropriate means (not shown) such as a limit switch. The extrusion device 1064 includes a stopper wall 1064a provided at the end of the conveyor 1061, a pusher 1064b for pushing out the lot A' along the stopper wall, and appropriate means (not shown) such as a shear cylinder for driving the pusher. Adjacent to the stations 103, 104, and 105 are appropriate conveyors (not shown) that receive and transfer the lots A' dropped from the unit body 10.

Therefore, the lots A' are successively supplied to the unit bodies 10 arriving at the station 102.

When station 105 is not in use, unit body 1
0 arrives at station 102 from station 103 until it leaves there, the inspection is performed according to the above-mentioned procedure, and defective sealed package lot A' with pinholes is inspected at station 103.
Lot A' without pinholes is sent out at station 104. After the unit body 10 passes through the station 104 and before Rotuna A' is introduced into the inspection chamber, the inspection chamber 1 after the inspection is transferred to the apparatus 2 and the trap 3.
It is desirable to dry it at 1.32. When a package A having large pinholes is discharged at station 105, the presence or absence of pinholes is inspected according to the aforementioned procedure while the unit body 10 arrives from station 102 to station 105 and leaves there. Lot A' with pinholes is discharged at station 105, lot A' with small pinholes is discharged at station 103,
Lot A' without pinholes is delivered at station 104.

As described above, according to the present invention, before inspecting for the presence or absence of pinholes,
A simple pinhole for sealed packages that can quickly collect vaporized substances adhering to the inspection room or the surface of sealed packages in the inspection room and accurately determine the presence or absence of pinholes under virtually no disturbance. - It has the advantage of being able to provide a method for checking the presence of oil.

[Brief explanation of drawings]

The drawings show an example of an apparatus for carrying out the method of the present invention.
The figure is a schematic cutaway side view of a device example, FIG. 2 is a schematic plan view of a part of another device example, FIGS. It is an adhering water temperature-thermal energy diagram. A...Sealed package, B...Package placement site, 1...Inspection room, 11...Entrance,
12...Outlet, 13...First lid device, 1
4... Second lid device, 15... Heating device, 2...
... Vacuum suction device for vaporization, 31, 32 ... Cold trap (heat exchanger for cooling), 4 ... Vacuum suction device for measurement, 5 ... Pressure measurement device, 10...
...Unit body, 101...Support base, 102
・・・・・・Supply station, 103, 105...
...Discharge station, 104... Delivery station. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1. A method for inspecting the presence of pinholes in a sealed package containing a vaporizable substance, placing the sealed package in an inspection chamber,
The inspection chamber is made airtight and the interior thereof is evacuated using a vaporization vacuum suction device connected to the inspection chamber to vaporize the vaporizable substances adhering to the inspection chamber and the surface of the sealed package. The substance is cooled and recovered in a cooling heat exchanger connected to the inspection chamber to substantially remove the vaporizable substances adhering to the inspection chamber and the surface of the sealed package, and then the inspection chamber is cooled. The test chamber is placed in a predetermined vacuum state using a measurement vacuum suction device connected to the test chamber, and then the vacuum suction in the test chamber is shut off to vaporize the test chamber. If the pressure increase value is greater than or equal to a predetermined reference pressure value, it is determined that there is a pinhole, and if it is smaller than the reference pressure value, it is determined that there is no pinhole. Of the step of vaporizing the vaporizable substance adhering to the surface of the package and the step of measuring the pressure increase in the test chamber, the vaporizable substance adhering to at least the test chamber and the surface of the sealed package to promote vaporization. A method for inspecting the presence or absence of pinholes in a sealed package, characterized in that in the step of vaporizing the sealed package, a location of the sealed package is heated.