JPH0781926B2 - Method and apparatus for inspecting air tightness of synthetic resin bottle container - Google Patents

Description

The present invention relates to a method for inspecting the airtightness of a synthetic resin bottle container mouthpiece, and an apparatus therefor.

[Prior Art] Although the airtightness of a bottle container is significantly reduced by the occurrence of scratches or chips in the bottle container, conventionally, as a method for inspecting the airtightness of such a bottle container, Air is sealed in the chamber, the pressure of the sealed air is measured after a certain period of time, and the so-called air leak type inspection method, which is a method of determining the quality of airtightness based on the measured value, has been performed by the inspection machine. .

[Problems to be solved by the invention]

However, in this inspection using the air leak type inspection machine, since air is enclosed in the entire bottle container for inspection, there are small scratches and the air pressure drops very slowly, which makes it difficult to perform a reliable inspection. Especially, in the automatic inspection in the manufacturing process line, a certain speed is required, so that it is impossible to perform an accurate inspection in the conventional inspection machine of this type.

In addition, in the polyethylene terephthalate resin bottle container that has been widely used recently, unlike other synthetic resin bottle containers, there is almost no perforation of the body or bottom, but due to the manufacturing process, the mouthpiece is scratched. However, the conventional method of injecting air into the entire bottle container for inspecting such a bottle container could not perform an accurate inspection.

Moreover, as shown in FIG. 4, the conventional inspection machine presses the upper end surface of the bottle container tightly with the rubber packing 22, so that the scratches generated at the upper end of the container are elastic. It will be covered and the airtightness of the bottle will be unintentionally maintained during the inspection. Therefore, it was not possible to accurately inspect the airtightness of the mouthpiece with this conventional inspection machine.

Bottle bottles that have a problem with the airtightness of the mouthpiece may leak the contents, or if the contents are carbonated drinks, the carbon dioxide gas may escape due to the internal pressure, leading to quality deterioration. It caused a big problem that

[Means for Solving Problems and Their Actions]

The present invention provides a method for accurately inspecting the airtightness of a synthetic resin bottle container, and an apparatus for the same, which solves the above problems.

First, the inspection method will be described with reference to the drawings.

(1) The method for inspecting the airtightness of the synthetic resin bottle container mouth tube 19 according to the present invention is such that a taper surface that extends downward of a hard airtight member is provided on the outer peripheral end of the upper end surface of the bottle container mouth tube 19 and is highly elastic. The member is brought into close contact with the inner peripheral surface of the mouth tube 19 to form the closed space 10 by using the mouth tube 19 including the upper end surface as a part of the wall, and air is enclosed in the closed space 10, and the air after a lapse of a certain time. The quality of the airtightness of the mouth tube 19 is determined based on the measured pressure value.

As described above, in the method for inspecting the airtightness of the synthetic resin bottle container 19 according to the present invention, since the air is enclosed only in the container 19 of the bottle container 18, the volume of the portion where the air is enclosed is limited. Is small, the air passage due to scratches or the like formed between the outer peripheral end of the upper end surface of the mouth tube 19 and the hard airtight member, the outer peripheral end of the upper end surface of the mouth tube 19 and the tapered surface of the hard airtight member. Since the contact is a line contact, the flow path resistance is small. Therefore, when the mouthpiece 19 has a flaw, the drop in the air pressure appears immediately and significantly.

Further, the airtight member that closely contacts the outer peripheral end of the upper end surface of the mouth tube 19,
Since it is made of a hard material, the air passage due to deterioration of the sealing function such as scratches formed at the upper end of the mouth tube 19 is not deformed and filled.

Next, the inspection device will be described.

(2) The airtightness inspection device 1 for the synthetic resin bottle container mouth tube 19 according to the present invention has a tubular shape in which the outer diameter of the lower end is set to be slightly smaller than the inner diameter of the mouth tube 19 while being supported so as to be vertically movable. A straight rod-shaped rod 3 having a sleeve 2 which is a part of an airtight member, and a tip 7 which penetrates through the sleeve 2 in a vertically slidable manner and whose outer diameter is set to be slightly smaller than the inner diameter of the mouth cylinder 19 at the lower end. And an outer diameter slightly smaller than the inner diameter of the mouth tube 19 located between the lower end surface of the sleeve 2 and the upper end surface of the tip 7 and having an assembling hole 21 for fitting and assembling to the rod 3. A seal body 5 which is a part of the airtight member having a thick-walled tubular shape and which is rich in elasticity, and is tightly fitted to the lower portion of the sleeve 2 slidably in the vertical direction and tightly fitted to the outer peripheral end of the upper end surface of the mouth tube 19. The bottom surface has a tapered surface 9 that spreads in contact with the bottom surface, and the taper surface 9 is sealed at the center thereof. A head 4 made of a hard material, which is a part of the airtight member provided with a supply port 8 for the incoming air, and is fitted and assembled to the sleeve 2 so as to press the head 4 against the upper outer peripheral end of the mouth tube 19. It is characterized by comprising a spring 6 and a spring.

The operation of the airtightness inspecting apparatus 1 for the synthetic resin bottle container 19 and the means to be described in more detail will be described with reference to FIG.

First, FIG. 1 shows a state before the sleeve 2 and the rod 3 enter the mouth cylinder 19 of the bottle container 18, but at this time, the head 4 fitted and assembled to the sleeve 2 also descends. To do.

As this descent progresses, as shown in FIG. 2, the sleeve 2
The rod 3 and the rod 3 are located inside the mouth tube 19, and the head 4
The tapered surface 9 comes into contact with the outer peripheral end of the upper end surface of the mouth tube 19. From this state, the sleeve 2 and the rod 3 further descend and reach the lower limit position.

This lower limit position can be set to an arbitrary position such as the lower end portion, the middle portion, or the upper portion inside the mouth tube 19 depending on the portion to be inspected.

When the sleeve 2 and the rod 3 reach the lower limit position as described above, the head 4 remains in contact with the upper end surface of the mouth cylinder 19, but is firmly pressed by the elastic force of the elastically deformed spring 6, and the mouth cylinder 19 Closely contacts the outer peripheral edge of the upper end surface.

The spring 6 must not prevent the sleeve 2 from entering the mouth tube 19 and have such elasticity that the head 4 is not displaced upward by the pressure of the enclosed air.

Since the bottom surface of the head 4 is a tapered surface 9 that spreads downward, it comes into contact with the outer peripheral end of the upper end surface of the mouth cylinder 19.

Since the tapered surface 9 makes close contact with the upper end of the mouth tube 19, both its dimensional accuracy and surface finishing accuracy must be high.

From the above state, as shown in FIG. 3, the rod 3 is displaced upward to press the highly elastic seal body 5 located between the lower end surface of the sleeve 2 and the upper end surface of the tip 7. The pressed seal body 5 is elastically deformed, and the outer peripheral surface closely contacts the inner peripheral surface of the mouth tube 19.

Therefore, the wall thickness of the seal body 5 needs to be thick enough to be pressed and elastically deformed to come into close contact with the outer peripheral surface of the mouth tube 19.

Depending on the elastic deformation allowable amount of this seal body 5, the head 4
Since the bottom surface is the tapered surface 9, it is possible to inspect a number of bottle containers 18 having different inner diameters of the mouth tube 19 with this single device.

The head 4, the seal body 5, and the mouth tube 19 formed in this way fill the sealed space 10 with air from the supply port 8 provided at the center of the head 4, and after a certain period of time, measure the pressure value of the air. Then, the airtightness of the mouth tube 19 is determined based on the measured value. This supply port 8 has a tapered surface 9
Must be provided in the central portion of the above, in other words, in the portion of the tapered surface 9 forming the closed space 10.

After the air pressure has been measured, the procedure is reversed and the inspection is completed. That is, the rod 3 is displaced downward, the pressure on the seal body 5 is released, and the seal body 5 elastically returns to its original shape. The outer diameter of the seal body 5 elastically restored is smaller than the inner diameter of the mouth tube 19. Next, when the sleeve 2 and the rod 3 are displaced upward and reach a certain elevated position, the head 4 released by pressing due to the elastic force of the spring 6 ascends together with the sleeve 2 and the rod 3.

〔Example〕

An embodiment of the inspection device 1 for carrying out the airtightness inspection method for the mouth tube 19 according to the present invention will be described with reference to FIGS.

This shows an automatic inspection device provided on the manufacturing process line of the synthetic resin bottle container 18, and includes a rotary table 15
It is rotated by and is positioned on the bottle container 19 on the manufacturing process line. At this time, the bottle container 18 is held by the hanger 17 sandwiching the lower portion of the flange 20 of the mouth tube 19 and locking the flange 20 from below.

The sleeve 2 is configured to be displaced up and down by a cam mechanism, and a cam follower 13 that receives a lifting displacement driving force from the cam 12 is integrally provided on the sleeve 2 via a slide block 14.

The rod 3 which is displaced up and down with respect to the sleeve 2 is displaced up and down by an air cylinder provided at the upper end of the rod 3.
Achieved by 11.

The head 4 that comes into close contact with the outer peripheral edge of the upper end surface of the mouth cylinder 19 is
It is necessary not to cover 19 scratches, and therefore the head 4 is made of a hard metal.

Further, it is an absolute requirement that the seal body 5 is rich in elasticity, and therefore, it may be made of natural rubber or synthetic rubber.

The seal body 5 is airtight with the inner peripheral surface of the mouth cylinder 19 and is also airtight with the rod 3 and the sleeve 2.

Further, the airtightness between the head 4 and the sleeve 2 is achieved by the O-ring 16 provided on the inner peripheral surface of the head 4.

〔The invention's effect〕

As described above, the method for inspecting the airtightness of the synthetic resin bottle container mouth tube 19 according to the present invention and the inspection apparatus 1 that enables the method are sealed when the bottle container 18 to be inspected has a flaw. In addition, the pressure drop of the air is fast, and it appears clearly so that accurate inspection results can be obtained and it can be used in the manufacturing process line where a certain speed is required.

Further, since the scratches on the upper end surface of the bottle container mouth 19 are not covered, the quality of the airtightness can be surely judged, and in addition to the above-mentioned effects, the content due to the poor airtightness which has been a concern in the past It also solves problems such as quality deterioration of objects all at once.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the position before entering the mouth tube 19,
FIG. 3 is a sectional view showing a state in which the mouth tube 19 is inserted, and FIG. 3 is a sectional view showing a state in which the closed space 10 is formed in the mouth tube 19.
FIG. 4 is a sectional view showing a conventional inspection device. Explanation of code 1: Airtightness inspection device, 2: Sleeve, 3: Rod, 4: Head, 5: Seal body, 6: Spring, 7: Tip, 8: Supply port, 9: Tapered surface, 1
0: Closed space, 11: Air cylinder, 12: Cam, 13: Cam follower, 14: Slide block, 15: Rotary table, 16: O-ring, 17: Hanger, 18: Bottle container, 19: Spout, 20: Flange, 21:
Assembly hole, 22: Rubber packing.

Claims (2)

[Claims] Claim: What is claimed is: 1. A taper surface extending downward of a hard airtight member is brought into close contact with an outer peripheral end portion of an upper end surface of a bottle container mouth, and an airtight member rich in elasticity is brought into intimate contact with an inner peripheral surface of the mouth tube so as to form an upper end surface. A closed space is created by using the mouthpiece containing the mouthpiece as a part of the wall, air is enclosed in the closed space, and the quality of the airtightness of the mouthpiece is determined based on the measured value of the air pressure after a certain period of time. Airtightness inspection method for bottle mouth bottles. 2. An airtightness inspection device for a synthetic resin bottle container mouth cylinder, which is supported in a vertically displaceable manner and has an outer diameter of a lower end slightly smaller than the inner diameter of the mouth cylinder. A rod that is a part of a rod, a rod that is slidable vertically in the sleeve so as to be slidable in the vertical direction, and has a tip with an outer diameter slightly smaller than the inner diameter of the mouth cylinder, and a fitting assembly for the rod. One of the airtight member having a thick cylindrical shape and an elastic hole rich in elasticity and having an outer diameter slightly smaller than the inner diameter of the mouth tube located between the lower end surface of the sleeve and the upper end surface of the chip. And a sealing body, which is a portion of the sleeve, and a downwardly expanding tapered surface closely fitted to the lower portion of the sleeve slidably and closely contacting the outer peripheral end of the upper end surface of the mouth cylinder. A part of the airtight member that has a supply port for enclosed air in the center That the manufactured head hard material, the mouth tube upper end surface peripheral edge 挿組-ordered spring synthetic resin bottle container mouth tube airtight inspection apparatus comprising a fitting in the sleeve so as to press the said heads.