JPS6025728B2 - How to test the internal vacuum of an ampoule or vial - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for electrically testing the internal vacuum of a glass ampoule or vial.

Generally, it may be necessary to maintain a vacuum inside a closed container made of glass or the like. For example, in ampoules and vials used for pharmaceuticals, etc., it is known that the inside of the container is kept in a vacuum to prevent the medicine filled inside from oxidizing and thus maintain its medicinal efficacy. ing. Prior Art In this case, when the inside of the container is evacuated and the container is closed with a rubber stopper, etc., the rubber stopper is sucked into the internal vacuum, resulting in a closure structure with good sealing performance, in other words, excellent sealing performance. It can be done.

In this type of closure structure, the internal vacuum of the container is usually 50T.
If the vacuum is as high as on or below, a good plugging state can be maintained, but if the vacuum is lower than that, such an effect cannot be maintained. Therefore, in order to maintain a good sealing condition, it is sufficient to inspect the internal vacuum level, but it is difficult to measure the internal vacuum level of a sealed container non-destructively from the outside, especially for ampoules. For items that require mass production, such as vials, the long time it takes to inspect each individual item is a factor that significantly impedes productivity. OBJECTS OF THE INVENTION Accordingly, a first object of the present invention is to provide a method by which the internal vacuum of an ampoule or a vial can be tested easily and quickly.

A second object of the present invention is to be able to inspect the internal vacuum level without affecting the closure state in any way, and therefore to ensure that the internal vacuum level of the ampoule or vial has a certain high vacuum level. The object of the present invention is to provide a method by which ampoules or vials lacking internal vacuum can be easily removed. Furthermore, a third object of the present invention is that the inspection is easy to carry out and can be carried out by simply touching the electrode to the outer surface of the ampoule or vial. Another object of the present invention is to provide an inspection method that enables automatic inspection.

SUMMARY OF THE INVENTION In order to achieve these objects, the present invention provides a method for inspecting the internal vacuum degree of an ampoule or vial, in which one electrode is brought into contact with the body side of the ampoule or vial as a point electrode. At the same time, the other electrode is arranged as a planar electrode in contact with the bottom surface of the body of the ampoule or vial so that the two electrodes face each other across the internal space of the ampoule or vial, and between the two electrodes A high frequency high voltage higher than the port Vp that causes a vacuum discharge phenomenon is applied to the internal space of the ampoule or vial, the current flowing between the two electrodes is detected, and this detected value is calculated based on the applied voltage and the internal vacuum degree of the ampoule or vial. The internal vacuum degree of the ampoule or vial is 50% when the detected value is greater than the standard value compared to a constant reference value that is set in advance by learning according to the required constant degree of vacuum.
This feature is characterized in that it is determined that the vacuum is in a high vacuum of less than Ton.

That is, the present invention provides a method of arranging a pair of electrodes in contact with the bottom surface of the ampoule or vial so as to face each other through the sides and internal space of the ampoule or vial, and then improving the insulation properties of the wall surface of the ampoule or vial. By applying a voltage Vp or more high enough to destroy the internal space to some extent, the internal space is made conductive and the magnitude of the current is detected.
When the vacuum is maintained at a high vacuum below the on level, the amount of current flowing through the internal space increases significantly compared to a constant reference value due to a so-called vacuum discharge phenomenon.

Therefore, depending on the voltage applied to the ampoule or vial, if the internal vacuum is higher than the required internal vacuum, the current inside the ampoule or vial will be lower than when the vacuum is lower. The magnitude of the current is detected, and this detected value is used as the applied voltage and the internal vacuum level of the ampoule or vial, which is a constant vacuum level of 50 Tom.
The degree of internal vacuum is determined by comparing it with a constant reference value that is set in advance through learning, and distinguishes between good and defective products. EXAMPLES The present invention will be specifically described below with reference to illustrated examples.

In Fig. 1, 1 is a container of a glass ampoule or vial whose internal vacuum level is to be tested, 2 is a rubber stopper with a collar of the container 1, and 3a and 3b are a pair of electrodes provided opposite to each other on the outer surface of the container 1. Then, one electrode is a point electrode 3a in the shape of a rod, needle, or sphere, and this is connected to the side surface la of the body of the container 1.
while the other electrode is brought into contact with a plywood-like planar electrode 3b.
Place the planar electrode 30 at the farthest position from the cap 20 by placing the bottom face lc of the container 1 on top of it.
position.

4 is a power source that applies a high frequency voltage between the pair of electrodes 3a and 3b, 5 is a detection resistor for detecting the current flowing between the electrodes 3a and 3b, and 6 is connected to both ends of the detection resistor 5. The bridge rectifier circuit 7 smoothes the output of the bridge rectifier circuit 6 with a resistor 8 and a smoothing capacitor 9, and compares the detection voltage VoUT generated across the resistor 10 with a preset threshold value voltage VTH, and calculates the result. This is a determination circuit such as a comparator that outputs a determination signal depending on the magnitude.

Now, in the above state, when high frequency high voltages V and N are applied between the pair of opposing electrodes 3a and 3b by the high frequency high voltage power supply 4, the current i flowing between the electrodes will depend on the magnitude of the voltage VIN and the size of the container 1. The current value is determined depending on the vacuum degree of the internal space lb, etc., and the current value is taken out as the detection voltage VoUr as described above via the bridge rectifier circuit 6. That is, electrode 3
When high frequency high voltages V and N are applied between a and 3b, a discharge is caused in an oblique direction between the side lb and bottom lc of the body of the ampoule or vial container without being affected by the cap 20, and the detection resistor 5 Detection voltage VoUT
is extracted as Therefore, this detection voltage V. UT
By comparing VTH with a preset threshold value VTH, it is possible to determine whether the internal vacuum degree of the container 1 is good or bad.
Figure 2 shows the applied high frequency high voltages V, N and the detection voltage V.
.

This shows the results of testing the relationship with uT for non-defective products and defective products. In the figure, the solid line g indicates a high-vacuum non-defective product with an internal vacuum level of 50 ton or less, the axis, ... indicates a low-vacuum defective product with an internal vacuum level of 50 ron or more. They are indicated by dotted lines h,, h2, . As is clear from Fig. 2, the power supply voltage VIN is 6 to 7 (KVp:
However, Vp is the peak voltage).
The saddles, . . . rise with a large gradient as V and N increase, whereas the defective products h,, h2, . . . only gradually increase with a small gradient.

For example, when V, N = 10 (KVp), good product g,, bag,
. . ., a detection voltage VoU of 1.5 (V) is obtained, whereas a defective product has a small detection voltage V of about 0.65 (V). Only uT is obtained. Therefore, by operating the slider 11a of the variable resistor 11 with respect to the reference power supply No. and setting the value voltage VTH to, for example, 1.2 (V), the comparator 7 can distinguish between good and defective products. It can be clearly distinguished by the presence or absence of output. Note that in the above, pass/fail was determined based on the rectified voltage, but for example,
A synchronizer, an oscilloscope, or the like may be connected to both ends of the detection resistor 5, and discrimination may be made based on the magnitude of the peak of the pulse. Similarly, a known peak detection means such as a peak detector may be used.

- Also, as a high-frequency high-voltage power source to be actually used, it is practical to use a voltage around 10 KVp in consideration of safety for the human body and ease of discrimination of detected values.

Effects of the Invention As is clear from the description of the embodiments above, the present invention provides a method for inspecting the internal vacuum degree of an ampoule or vial by placing one electrode as a point electrode in contact with the side surface of the body of the ampoule or vial. At the same time, the other electrode is arranged as a planar electrode in contact with the bottom of the body of the ampoule or vial so that the two electrodes face each other across the internal space of the ampoule or vial, and the ampoule is placed between the two electrodes. Alternatively, apply a voltage higher than Vp that causes a vacuum discharge phenomenon to the internal space of the vial, detect the current flowing between both electrodes, and use this detected value as the applied voltage and the internal vacuum degree of the ampoule or vial. Compared to a certain standard value set in advance by learning according to a certain degree of vacuum 5 orr, when the detected value is larger than the standard value, the internal vacuum degree of the ampoule or vial is a high vacuum of 50 Tom or less. The present invention provides a novel inspection method characterized in that it determines whether the

Therefore, according to the present invention, the internal vacuum level of an ampoule or vial can be inspected very easily and quickly, which has been difficult in the past. Additionally, a pair of electrodes can be attached to ampoules or vials in which a metal cap made of aluminum or the like is placed over the rubber stopper to strengthen the sealing properties of the rubber stopper. Because the sides and bottom of the body of the vial are opposed to each other, the applied high-frequency, high-voltage discharge is not affected by the cap and is caused in an oblique direction between the side and bottom of the body of the ampoule or vial. This has the advantage that defective products can be detected reliably.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram showing an embodiment of the method of the present invention, and FIG. 2 shows the applied voltage VIN as Yokoto and the detected voltage V. It is a graph showing the relationship between the two, with UT as the vertical axis. 1
...Container, 2...Rubber stopper, 3a, 3b
...Pair of electrodes, 4...Power source, 5...
...Detection resistor, 6,7...Discrimination circuit. Figure 1 Figure 2

Claims (1)

[Claims] 1 A method for testing the internal vacuum of an ampoule or vial, in which one electrode is placed as a point electrode in contact with the side of the body of the ampoule or vial, and the other electrode is placed as a planar electrode on the body of the ampoule or vial. A high voltage of 6 KVp or more that is placed in contact with the bottom surface so that the two electrodes face each other across the internal space of the ampoule or vial, and that generates a vacuum discharge phenomenon in the internal space of the ampoule or vial between the two electrodes. A voltage is applied, a current flowing between both electrodes is detected, and this detected value is converted to a certain value set in advance by learning according to the applied voltage and a certain degree of vacuum of 50 Torr required as the internal vacuum degree of the ampoule or vial. An inspection method characterized in that when the detected value is compared with a reference value, it is determined that the internal vacuum of the ampoule or vial is at a high vacuum of 50 Torr or less.