JPS58613B2 - Insulating container defect inspection method and device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention electrically detects the presence or absence of defects such as pinholes or cracks in an insulating container sealed with an electrolyte or non-electrolyte, such as an ampoule containing an injection solution. The present invention relates to a method for inspecting and an apparatus for automatically detecting the defects by implementing the method.

For example, if there are pinholes or cracks in an ampoule containing a sterilized drug solution sealed in a glass container to ensure long-term storage, bacteria may enter the atmosphere through the pinholes or cracks. Alternatively, the chemical solution inside may leak out and make the ampoule unusable, so inspecting this type of ampoule for the presence of pinholes and cracks constitutes an important step in its manufacturing process.

Conventionally, as a method for electrically testing the presence or absence of pinholes and cracks in a glass container sealed with a conductive liquid such as an ampoule, for example, Japanese Patent Application Laid-Open No. 48-45250 discloses a method for electrically testing a glass container sealed at an ultra-high temperature. A voltage is passed between electrodes to which a voltage is applied, and in this case, the voltage is selected to a value that will not cause flash sparks when there are no defects in the glass container, but will cause flash sparks where there are pinholes or cracks in the glass container. However, a method has been proposed in which a flash current generated through the glass container is detected using this voltage to test for defects in the glass container.

In this method, one electrode of an AC high-voltage power source is brought into contact with the glass container to be tested, while a spark gap is provided between the other electrode of the power source and the portion of the glass container to be tested.
A sealing defect where the sealed liquid is seeping out on the surface of the glass container is detected based on the presence or absence of an abnormal increase in the flash discharge current generated in the spark gap, and the detection of the defect depends on the above-mentioned condition. Because the generation of the flash discharge current that occurs in the spark gap is extremely unstable, it takes a considerable amount of time in the early stages of the test for the specified discharge phenomenon to occur, and sometimes pinholes on the order of a few microns occur in the container. Even if flash discharge occurs, it may not be possible to detect it because no flash discharge occurs, making it difficult to conduct precise tests.

In addition, the electrode to which ultra-high voltage is applied is formed into a needle shape with a sharp tip to generate spark discharge, and it is difficult to make this needle-shaped electrode face the entire circumference of the glass container. Therefore, this type of method is limited to a local inspection of the glass container, and it is difficult to accurately align each part of the glass container to be tested with the electrode, so it is difficult to perform this type of inspection continuously and automatically. I couldn't do it like that.

Furthermore, in order to improve the test accuracy of this type of method, it is conceivable to increase the AC high voltage current to ensure that a flashover discharge current occurs in the spark gap, but in this case, the flashover discharge current is reliable. Even if a flashover current occurs, the energy of the discharge current becomes abnormally large, which may destroy the container itself, and if the overall flash discharge current increases, pinholes may occur in the container. There was a drawback that the magnitude of the flash discharge current generated could be misjudged depending on the presence or absence of the flash current.

Furthermore, in the conventional method, the accuracy of the test is not accurate, and therefore pinholes cannot be detected when a non-electrolyte solution is sealed in the container.

The present invention eliminates the drawbacks of the above-mentioned conventional methods and proposes a new method for precisely inspecting an insulating container sealed with an electrolyte solution or a non-electrolyte solution for defects due to poor sealing through a simple process. At the same time, we have created an inspection device with a simple configuration to automate and implement this inspection method.

That is, the present invention enables the inspection of containers of this type by applying a direct current high voltage power source to the container to be inspected, without using the flash discharge current generated in the spark gap between the electrode of the alternating current high voltage power source and the portion to be inspected of the glass container as in the past. to detect the charging current, or detect the neutralizing current that neutralizes this charging current, and compare the magnitude and shape of the charging current and neutralizing current with a certain reference value. The present invention is designed to determine the presence or absence of defects in the container.

The charging current value of a glass container charged using a DC high-voltage power supply is usually several times larger when the glass container is sealed with an electrolyte or non-electrolyte than when it is an empty, unsealed glass container. Even if the container is sealed, the value is much smaller than that of a container with a pinhole, and even if the container is sealed, there is a crack and the filled liquid leaks out. The presence or absence of defects can be detected reliably and accurately.

For this reason, the present invention provides an electrode member facing the part to be inspected of the insulator container to be inspected across a certain space, and also provides a switch means for connecting the electrode member to a high DC voltage or to ground. By ON-OFF operation of the switch means, the inspected part of the container is charged or uncharged via the electrode member, and the amount of charge charged on the container at that time is detected. It is something.

Further, the area to be inspected of the container is changed by rotating the container with a screw while maintaining a constant distance from the electrode member, so that the entire circumferential surface of the container is inspected. be.

Furthermore, the electrode member is formed into a flat plate having a constant length in the conveyance direction of the container, and when the container is conveyed, a constant space is always maintained between the electrode member and the electrode member over the constant length. By placing the containers facing each other at a distance, and detecting the amount of charge on the containers as described above at any time or all the time, it is possible to automatically inspect the containers after they are transported.

That is, a container to be inspected is always separated from an electrode member having a certain length by a certain space, and the container to be inspected is transported in the length direction of the electrode member while rotating around its axis, and at the same time, the switch means of the electrode member is turned on. By repeating the 0N-OFF operation at regular rotation intervals and continuously detecting the amount of charge on the container at each time, the amount of charge on the container can be detected on the entire circumference of the container while the container is being transported in one direction. The presence or absence of defects can be automatically inspected.

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.

FIG. 1 shows that the body 1a of the injection ampoule 1 is placed on the cathode plate 2, and the head 1b of the ampoule 1 and the upper part of the body 1a are used as inspection sites to be charged or charged using the anode plate 3. This shows a device that eliminates this problem.

The ampoule 1 is a hermetically sealed insulating container made of glass or the like, in which an electrolyte or a non-electrolyte solution 4 such as a chemical solution is sealed.The ampoule 1 has a head part 1b with a small inner diameter and a body with a large inner diameter and has an approximately constant thickness. In FIG. 1, the upper circumferential surfaces of the head and torso are the inspected parts, and the presence or absence of defects such as pinholes and cracks in these parts as sealing defects is electrically inspected.

The anode plate 3 is connected to the positive side of the DC high voltage power supply 5, and the cathode plate 2
are connected to the negative side of the DC high voltage power supply via a current limiting resistor 6 or a measuring resistor 7, respectively.

The cathode plate 2 is a flat plate electrode in the shape of a transverse arc that contacts the body portion 1a of the ampoule 1 over a wide area, and during the inspection, the cathode plate 2 is kept in contact with the ampoule 1 over almost the entire surface at all times so that the ampoule is highly charged.

The anode plate 3 is a flat electrode whose lower edge is roughly similar to the outer shape of the ampoule 1, and whose lower end is connected to the body 1 of the ampoule 1.
For example, the above-mentioned DC high voltage power supply device 5 with a voltage of 10KV to 15KV and a current limiting resistor 6 of 10MΩ to 50MΩ are placed with a gap of 2 mm between them, with a space of a certain size separated above the head 1b and the head 1b. Even when the above voltage is applied, flash discharges such as corona discharge, arc discharge, and spark discharge do not occur under normal conditions, but the body 1a and head 1b of the ampoule are caused by the high voltage DC electric field of the anode plate 3. Allow it to become electrically charged.

In this case, the potential of the gap between the anode plate 3 and the cathode plate 2 is set to 1KV/
mm to about 1.5 KV/mm to prevent short-circuit discharge.

When the position of the ampoule 1 is not changed, the lower end line of the anode plate 3 may be formed into a sharp needle shape, but when the ampoule 1 is conveyed in one direction, the anode plate 3 is fixed in the conveying direction. Form into a flat plate having a length.

An on-off type switch means 8 that bypasses the anode plate 3 is interposed between the current limiting resistor 6 and the earth 7 in parallel with the anode plate 3, and the anode plate 3 is turned on and off by turning the switch means 8 on and off.
The connection and disconnection between the terminal and the DC high-voltage power supply device 5 are performed.

Since the DC high voltage power supply 5 has a high voltage, this switch means 8 uses a device with a high withstand voltage such as a high voltage triode vacuum tube 9.

The high-pressure triode vacuum tube 9 is, for example, a 6B54 type GT tube.
Connect that plate p to the anode plate 3, while the grid g
is connected to the grid voltage controller 10 and the cathode K
is connected to the ground or the negative side of the DC high voltage power supply 5, and the heater h is connected to the DC low voltage power supply 11.

This high-voltage triode vacuum tube 9 has a withstand voltage of 30,000 volts or more, and its plate current Ip and grid current Ig have a curved relationship as shown in FIG. When connected to 20 volts, the plate current p becomes zero and does not flow, while if the grid current Ig is set to zero, a sufficient plate current will flow.

Such switching of the grid current Ig between -20 volts and zero is performed by the grid voltage controller 10.

In other words, when the grid voltage controller 10 is turned on, the DC low voltage power supply of 120 volts is connected to the grid g of the high voltage triode vacuum tube 9, so the plate current of the high voltage triode vacuum tube 9 stops flowing, and the apparent The upper high-voltage triode vacuum tube 9 is in the off state, so that the anode plate 3 has no relation to the negative side of the DC high-voltage power supply 5, while when the grid voltage controller 10 is turned off to zero volts, the high-voltage triode vacuum tube 9 The grid current from the DC low-voltage power supply 11 stops flowing through the grid g, and the apparent upper limb high-voltage triode vacuum tube 9 turns on, so that the anode plate 3
It comes to be connected to the ground 7 or the negative side of the DC high voltage power supply device 5 via.

Therefore, by turning on and off the grid voltage controller 10, the high voltage triode vacuum tube 9 can be turned off or on, and the anode plate 3 can be disconnected or connected to the ground or the negative side of the DC high voltage power supply 5. The high-voltage DC from the DC high-voltage power supply device 5 acting on the anode plate 3 is received by the high-voltage triode vacuum tube 9 and passed therethrough, while the grid voltage controller 10 that switches the high-voltage triode vacuum tube 9 It is sufficient to have a low withstand voltage that can receive and flow the grid current that makes the plate current zero.

If the grid voltage controller 10 uses an on-off oscillator such as a multivibrator, the high-voltage triode vacuum tube 9 can automatically repeat on-off as described above.

Note that the switch means 8 may use a high-voltage transistor or a mechanical switch in addition to the high-voltage triode vacuum tube.

In parallel with the switch means 8, a measuring resistor 7 is interposed between the cathode plate 2 and the negative side of the DC high voltage power supply 5 or the ground, and a discriminating device 12 is provided for detecting the potential at both ends of the measuring resistor 7. The current flowing from the cathode plate 2 when charging or discharging is detected by the discriminating device 12 as one potential.

As shown in FIG. 2, the sorting device 12 compares its input with a predetermined reference value using a variable resistor and outputs an output depending on the magnitude of the input, and a reference value setting circuit 13, for example, a differential amplifier. It is composed of a double force value comparison circuit 14 or a Schmitt circuit, which outputs an output only when the current passing through the measuring resistor 7 is equal to or higher than a reference value, and connects it to an electromagnetic magnet for ampoule discharge operation via a flip-flop 14 and a shift register 15. 16 to operate.

The current limiting resistor 6 interposed between the anode plate 2 and the DC high-voltage power supply 5 is normally about 10MΩ to 50MΩ, and when the switch means 8 is turned on, the short-circuit current of the power supply of the DC high-voltage power supply 5 is suppressed. Performs a limiting action.

In the device constructed as described above, the ampoule 1 has a first capacitor C1 between the outer surface and the inner surface of the upper part as a circuit.
is formed, the solution in the ampoule has one resistance R1, and it can be considered that a second capacitor C2 is formed between the outer surface and the inner surface of the lower part of the ampoule.

Furthermore, while the charging phenomenon caused by the anode plate 3 can be regarded as the formation of a third capacitor, when the ampoule is defective and the solution inside the ampoule leaks as described later, the charging phenomenon caused by the anode plate 3 can be considered to be the formation of a third capacitor C1. It can be assumed that there is one leakage resistor connected in parallel, and the third capacitor, first capacitor C1, solution resistor R1, and second capacitor C2 are the current limiting resistor 6 of the DC high voltage power supply 5 and the discrimination device. The 12 measuring resistors 7 are successively connected in series.

Note that the current limiting resistor 6 and the switch means 8 are replaced with each other as shown in FIG. 9, and the switch means 8 and the discharge resistor 6 are connected in series to the DC high voltage power supply 5, and may be connected in parallel with the current limiting resistor 6.

Below, we will explain how to inspect ampoule 1 using the above-mentioned device when there is no defect in the ampoule (990, C, D in Figure 5), and when there is a pinhole in the ampoule (Ho, H in Figure 5).
If the ampoule is defective and the internal solution is leaking (see Figure 5), If the ampoule is empty (see Figure 5), if the ampoule is empty (see Figure 5). nu, ru) will be explained.

First, the ampoule 1 is placed at the position to be inspected, that is, the lower part of its body 1a is placed on the cathode plate 2, and the body 1a and the upper part of the head 1b, which are the parts to be inspected, are placed between the anode plate 3 and the anode plate 3. Place it with a space of

Then, with the switch means 8 turned off, a DC high voltage from the DC high voltage power supply 5 is applied between the anode plate 3 and the cathode plate 2 via the current limiting resistor 6, and the anode is connected to the anode as shown in FIG. The DC high voltage electric field of the plate 3 causes, for example, a positive charge on the surface of the portion of the ampoule 1 to be inspected.

At this time, no spark-like flash discharge occurs between the anode plate 3 and the ampoule 1 as in the conventional case.

The ampoule 1 is charged as shown in the circuit shown in Figure 5C.
Between the glass container and the internal solution sealed inside,
For example, the upper two parts of the inner surface of the glass container are negatively charged, and the lower part is positively charged with the same potential, but it is important to provide enough contact area between the ampoule body 1a and the cathode plate 2. For example, the potential charged on the ampoule 1 increases.

After charging the ampoule 1 in this way, the switch means 8
When you turn on the anode plate 3 and connect it to the ground or the negative side of the DC high voltage power supply 5, the electric field of the DC high voltage on the anode plate 3 is eliminated, and at the same time, due to this no electric field, as shown in the opening of Figure 5, The positive electrons that were previously attracted to the outer surface of the charged area of the ampoule 1 to be inspected are neutralized by the negative electrons in the surrounding external field, and the charge inside the glass container of the ampoule is neutralized. , the ampoule 1 returns to its normal state before being charged.

As described above, the current that charges the ampoule when the switch means 8 is turned on can be detected by the discriminator 12 as a charging current as shown in FIG. 4, that is, as the potential across the measuring resistor 7. The current that eliminates the charge on the ampoule when 8 is turned off is called the elimination current.
In other words, the discrimination device 12
It can be detected by

At this time, if the ampoule 1 is normal and has no defects such as pinholes and contains a certain amount of internal solution, the fifth
As shown in Fig. D, one unit of charging or discharging current i1 flows, but if the ampoule 1 is empty and does not contain a certain amount of internal solution as shown in Fig. 5, then as shown in Fig. 5 As shown in the circuit, the fifth
As shown in the figure, a slight charging or canceling current i3 of less than half a unit flows.

In addition, even if the ampoule 1 has a defect such as a pinhole, as shown in Figure 5 E and F, if the internal solution does not leak to the outer surface of the ampoule, the circuit shown in Figure 5 G, etc. For example, the negative potential inside the glass container of the ampoule 1 is attracted to the outside world through the defect, and more positive potential is charged inside the ampoule. A charging or canceling current i2 flows.

Furthermore, when the internal solution leaks to the outer surface of the ampoule 1 as shown in FIG. Since the flashover discharge occurs continuously during this period, a discharge current i4 of about 2 units or more flows continuously as shown in the fifth diagram.

Therefore, if such a current i is detected by the discriminating device 12, it will be determined whether the ampoule 1 is normal with no defects, has an internal solution, or has an abnormality with a major defect such as whether the internal solution is leaking. It is possible to determine what is.

In any case, it is possible to electrically test whether the ampoule 1 is normal or not based on the input to the discriminating device 12 generated by turning the switch means 8 on and off.

For example, a certain criterion for discriminating the input may be predetermined in this discrimination device 12, and the value of another input is above the criterion value for discriminating empty ampoules of one low value, and one high If the input value is lower than the standard value that distinguishes ampules with pinholes, and the integral value within a certain time of input is lower than the standard value that distinguishes ampules with internal solution leakage, the ampoule is considered normal. If the output is set to output, good ampoules can be automatically selected.

According to such an inspection method, the ampoule 1 can be more accurately inspected because the charging of the ampoule 1 and its elimination occur more easily, reliably, and in a stable manner than with conventional flash discharge. In addition, since the current flowing through the ampoule 1 is small enough to charge the ampoule, the ampoule 1 will not be destroyed by the current flowing through the ampoule 1, as in the case of In some cases, the entire inspection can be simplified or downsized.

Next, FIGS. 6, 7, and 8 show an apparatus for continuously inspecting multiple locations of the ampoule 1 at once using the same inspection method as described above.

The apparatus shown in FIGS. 6 and 7 is a device in which the ampoule 1 of the apparatus shown in FIG. 1 is automatically conveyed from one supply position to a fixed inspection position, and then conveyed to a take-out position. A screw conveyor 20 that continuously conveys the ampoule 1, a means 21 for driving the conveyor 20,
The receiver for guiding the neck 1c of the ampoule 1 is equipped with a stand 22, while the anode plate 3 is fixed at a constant interval above the conveyor, and the anode plate 3 is connected to a DC high voltage power supply via a current limiting resistor 6. 5 is connected, and the cathode plate 2 is formed into a roller shape so as to be in constant pressure contact with the conveyor.
The measuring resistor 7 and the printing device 12 are connected in parallel and grounded together.

The conveyor 20 is made of an insulating synthetic resin, and is made of an insulating synthetic resin. A conductive metal coating 23 is applied only to the outer surface of a certain length corresponding to the pair of anode plate 3 and cathode plate 2, for example, a width of 20 mm, and the axis is moved at a constant speed, e.g. When rotated at rotation/sec, the movement in the axial direction is 20 mm/rotation.

The cathode plate 2 is pressed against the metal coating 23 by a spring (not shown), so that the apparent upper limit electrode plate 2 and the metal coating 23 constitute the cathode plate shown in FIG.

The receiver platform 22 is made of a flat plate or wire provided on the front surface of the conveyor 20, approximately parallel to the conveyor, and over approximately the same length as the conveyor. Guide the transportation.

That is, the ampoule 1 is placed at one supply position of the conveyor 20, its body 1b is fitted into the trough 20a of the conveyor 20, and its neck 1c is placed on the tip of the tray 22.
When the conveyor 20 is rotated by the driving means 21, the ampoule 1
are pushed by the peaks 20b of the conveyor 20 and conveyed along the axial direction of the conveyor 20. At the same time, the ampoule 1 is moved along its axis by friction between the contact surfaces of the conveyor 20 and displacement of the contact surfaces due to the rotation. Since the ampoule 1 is rotated around the center, the ampoule 1 is continuously conveyed at a constant speed along the conveyor 20 from the supply position to the inspection position and then to the take-out position while rotating.

The ampoule 1 rotates once around its axis while being conveyed by one pitch of the screw of the conveyor 20, for example, 20 mm, so that the body 1b of the ampoule 1 is constantly rotated while the ampoule 1 rotates once at the inspection position of the conveyor 20. While the lower part of the ampoule 1 is in contact with the metal coating 23, an anode plate 3 of a certain length, for example, 20 mm, is placed at a certain distance above the part to be inspected of the ampoule 1 and always faces oppositely to the ampoule 1. The metal coating 23 of the conveyor 20 and the cathode plate 2, which are always in contact with each other, are always brought into pressure contact.

In other words, when the ampoule 1 passes through the inspection position of the conveyor 20 while making one rotation, the body 1b of the ampoule 1 is always
is in contact with the cathode plate 2 through the metal coating 23 at its lower part, while its upper part faces the anode plate 3 at a certain interval, so that the first
A circuit for ampoule testing as shown in the figure is constructed.

When such a test circuit is constructed, the switching means 8 is turned on and off by, for example, its grid voltage controller 10.
is controlled by an oscillator to produce a constant cycle of, for example, 10mm5ec.
If this is repeated every time, the switch means 8 will be turned on and off 20 times during one rotation of the ampoule 1 as described above, and the ampoule 1 will be rotated at intervals of about 18 degrees around its axis. Thus, the presence or absence of a defective portion of the ampoule 1 as described above can be detected on the entire circumferential surface by the discriminating device.

If there are multiple inspection positions for the ampoule 1, the accuracy of the inspection can be further improved.For example, as shown in FIG. If you change the position of the ampoule and place the ampoule on the conveyor with the body close to the neck of the ampoule so that the anode plate also faces the bottom of the body of the ampoule, the presence or absence of the defect will be detected on the entire surface of the ampoule. It will be possible to automatically detect it with a discriminator.

In this way, when a defective part of an ampoule 1 is detected, the ampoule discharge operation electromagnetic magnet 16 is activated at the take-out position of the conveyor 20 by the detection signal to remove the ampoule 1, and the ampoule 1 is moved in one direction. It is possible to realize a fully automatic machine that can continuously and automatically inspect the entire surface while being transported.

As described in detail in the above embodiments, the present invention is capable of accurately inspecting defects such as pinholes in an insulating container such as an ampoule filled with a liquid by simple operation using a device with a simple configuration. It is possible.

Furthermore, it goes without saying that the present invention can be modified in various ways, such as reversing the poles of the anode plate and the cathode plate, within the scope of the gist of the invention, in addition to those detailed in the above embodiments. be.

[Brief explanation of the drawing]

FIG. 1 is a block circuit diagram showing a schematic configuration as a first embodiment of the device according to the present invention, FIG. 2 is a detailed diagram of the discrimination device shown in FIG. 1, and FIG. 3 is a high-pressure triode vacuum tube shown in FIG. 1. Characteristic diagram of
4 is a waveform diagram of the detection signal in FIG. 1, FIG. 5 is an explanatory diagram showing the ampoule charging phenomenon in FIG. 1, and FIG.
The figure is an explanatory diagram showing a schematic configuration as a second embodiment of the device according to the present invention, Figures 7 and 8 are sectional views of the main parts of Figure 6, and Figure 9 is a modification of Figure 1. FIG. 1... Ampoule, 2... Cathode plate, 3.
... Anode plate, 4 ... Filled liquid, 5 ...
...DC high voltage power supply, 6,7...Resistor, 8.
... Switch means, 12 ... Discrimination device,
20... Screw conveyor.

Claims (1)

[Scope of Claims] 1. At least once or more using an electrode member that applies a DC high voltage to a region to be inspected of an insulating container containing a liquid, which faces the region to be inspected with a certain space between them. A defect inspection method for an insulating container, characterized in that the container is charged with electricity, and the amount of charge charged on the container is detected at any time during each charging time. 2. Charge the part to be inspected of the insulating container that encloses the liquid at least once using an electrode member that applies a direct current high voltage, facing the part to be inspected with a certain space between them, and reduce the time for each charge. The apparatus is used in a defect inspection method for an insulating container, in which the amount of electric charge charged on the container is detected at any time, and the device is installed at one end of the part to be inspected of the insulating container in which a liquid is sealed, with one side separated by a certain space. The electrode members are arranged to face each other, and the other electrode member is provided in contact with the other end of the container, and a DC high voltage power source is connected between the two electrode members, and a switch is connected to the energizing circuit of the one electrode member. 1. A defect inspection device for an insulator container, further comprising a charge detector on the other electrode member. 3. A defect in an insulating container in the apparatus according to claim 2, characterized in that the one electrode member is formed into a flat plate having a planar extension when viewed from the inspected part of the container. Inspection equipment. 4. A defect inspection device for an insulating container as set forth in claim 2, wherein the other electrode member is formed by a screw conveyor on which the container is placed and conveyed in one direction. .