JP2000131182A - Method and apparatus for inspection of airtightness defect of airtight container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect an airtightness defect easily and in a short time with a simple and low-cost apparatus by a method, wherein the opening of a deformable enclosure is brought into close contact with a face to be detected, so as to be pressed and the collapse size of the face to inspected, which is collapsed due to air pressure in the inside of the enclosure, raised due to the deformation of the enclosure. SOLUTION: A bellows 5 is brought into close contact with the surface of a lid body 2 as a face to be inspected, and a chamber 6 is pressed downward. Then, the air pressure inside rizes, and the surface of the lid body 2 collapses. At this time, a magnetic body 10 at the upper end of a float 13 which comes into contact with the surface of the lid body 2 compresses a sponge member a little, so as to be brought close to a magnetic sensor 8. Then when the size between the sensor 8 and the magnetic body 10 is measured, the dimension to the sensor 8 from the surface of the lid body 2 becomes H1. When a difference (H1-H0) between a dimension H1 and the prescribed dimension H0 up to the surface of the lid body 2 from the sensor 8 when the lid body 2 is not pressed is within a prescribed value α, a container to be inspected is determined to be a nondefective. When a container body 1 and the lid body 2 are not brought sufficiently into close contact, the measured dimension H1 becomes large. The difference (H1-H0) becomes larger than the prescribed value α, and airtightness defect is determined.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for inspecting a hermetically sealed container which mainly comprises a container main body and a lid thereof and in which food and drink are sealed.

[0002]

2. Description of the Related Art A conventional technique is disclosed in Japanese Patent Laid-Open No. 2-776.
There is one described in JP-A-33.

[0003] The invention described in this publication is a method for detecting poor sealing of a sealed container having a joint, by increasing the pressure only on the outside of the wall surface of the sealed container not including the joint. When the wall surface is depressed into the inside, the depressed size is detected, and when the depressed size is larger than a predetermined size, it is determined that the hermetically sealed container has poor sealing.

[0004] More specifically, a pressurized chamber that is in close contact with only a side wall not including a joint portion of a sealed container, a sensor mounted inside the pressurized chamber and measuring a distance to the wall surface, Pressurizing means for sending and pressurizing air into the chamber, and taking the difference between the sensor and the wall surface during pressurization and the distance from the sensor to the wall surface during non-pressurization, and taking the difference as a predetermined value. Means for comparing,
When the difference is different from a predetermined value, a means is provided for notifying that the sealing failure has occurred in the sealed container.

[0005] That is, by supplying high-pressure air into the pressurized chamber, the surface to be detected of the sealed container is pressurized and depressed, and it is determined whether or not sealing failure occurs due to the depressed size. Things.

[0006]

As described above, in the prior art, the air supply means for supplying high-pressure air into the pressurized chamber was required, so that the entire apparatus became complicated and the price became high. I was

Also, it takes time to supply air,
There is a risk that the detection time will be long.

Further, when the container body is formed of a thin plastic and the lid is also formed of a plastic film, if the pressure in the pressurizing chamber is excessively increased, the film is excessively deformed and the commercial value is reduced. There was a risk of dropping.

Further, even in a state where the lid is simply placed on the container body, the pressurizing means operates, and the contents of the container are blown off by the compressed air by the pressurizing means, thereby contaminating the surroundings. There was a risk of causing it.

Furthermore, when the lid is not provided, there is a possibility that the lower end of the pressurizing chamber comes into contact with food or the like stored in the container body and becomes soiled.

[0011]

According to a first aspect of the present invention, a pressure is applied to a surface to be detected of a hermetically sealed container to which a plurality of members are not bonded, the surface not including the joint portion, and the depressed dimension of the surface to be detected is reduced. In the method of inspecting sealing failure by measuring,
An opening is formed in a portion of the housing that is at least partially deformable, the opening facing a surface to be detected of the sealed container, and measurement means for measuring a distance to the surface to be detected is provided inside the housing, By pressing the opening of the body in close contact with the surface to be detected and deforming the housing to reduce its volume to increase the internal air pressure, when the surface to be detected is depressed due to the increase in pressure, A method of inspecting sealing failure of a hermetically sealed container, comprising measuring the depressed size and determining that the hermetically sealed container has defective sealing if the depressed size is larger than a predetermined size.

According to the present invention, the housing is deformed so as to reduce its volume by bringing the opening of the housing into close contact with the surface to be detected, thereby increasing the internal pressure. When the detection surface is depressed, the depressed dimension is measured, and when the depressed dimension is larger than a predetermined dimension, it is determined that there is a sealing failure in the sealed container, and high-pressure air is injected into the housing. Since the pressure in the housing is increased without supplying the air, the step of supplying air into the housing is not required.

The second invention is based on the first invention, and a bellows made of a soft member is attached to the opening of the housing, and the bellows of the housing is pressed against the surface to be detected of the sealed container. , The bellows compresses to raise the internal pressure,
When the surface to be detected is depressed due to the increase in the pressure, the depressed dimension is measured, and when the depressed dimension is larger than a predetermined dimension, it is determined that a poor sealing is present in the sealed container. It is an inspection method.

According to the present invention, a bellows made of a soft member is attached to the opening of the housing, and the bellows of the housing is brought into close contact with the surface to be detected of the sealed container and pressed, and the bellows is compressed to compress the inside. Since the air pressure is raised and the air pressure in the housing is increased without supplying high-pressure air into the housing, a step of supplying air into the housing becomes unnecessary.

A third invention is the first invention or the second invention.
In the pre-process of pressing the housing against the surface to be detected of the sealed container, when the surface to be detected is mechanically pressed and the surface to be detected is depressed by the pressing, the depressed dimension is measured. If the recessed dimension is larger than a predetermined dimension, the method is a method for inspecting a hermetically sealed container for determining that the hermetically sealed container has a defective sealing without measuring the pressure by pressing the housing.

In the present invention, for example, when a plurality of members are not sufficiently joined, when the surface to be detected is pressed mechanically, the surface to be detected is greatly depressed by the pressing. Thus, it is possible to determine that there is a poor sealing in the hermetically sealed container without having to press the housing to perform measurement.

According to a fourth aspect of the present invention, there is provided a sealed container in which a plurality of members are joined, by applying pressure to a surface to be detected which does not include the joint, and measuring a depressed dimension of the surface to be detected. In the apparatus for inspecting, the opening is formed in a portion of the sealed container facing the surface to be detected, and at least a part of the housing is deformable, and the distance to the surface to be detected is mounted inside the housing. Measuring means for measuring, and pressing means for pressing the housing by bringing its opening into close contact with the surface to be detected and comprising: When the detected surface is depressed due to the increase in the pressure, the depressed dimension is measured, and when the depressed dimension is larger than a predetermined dimension, the sealing is performed. Poorly sealed container A sealing failure inspection apparatus of a sealed container, characterized in that it is determined that that.

The operation of the present invention is substantially the same as that of the first invention.

The fifth invention is based on the fourth invention and is provided with means for mechanically pressing the surface to be detected, which is located in a step before the case is pressed against the surface to be detected of the sealed container. ,
When the surface to be detected is depressed by the pressing, the depressed dimension is measured by the measuring means, and when the depressed dimension is larger than a predetermined dimension, the housing is pressed into the sealed container without being measured by pressing the housing. This is a sealing failure inspection device for a sealed container that determines that sealing failure exists.

The operation of the present invention is substantially the same as that of the third invention.

[0021]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of the present invention. FIG. 1 is a partially enlarged front view showing a stage before the first step, and FIG. 2 is a partially enlarged view showing a stage after the first step. Front view,
FIG. 3 is a partially enlarged front view showing a stage before the second step, FIG. 4 is a partially enlarged front view showing a stage after the second step, FIG. 5 is a flowchart, and FIG. 6 is an overall front view.

In these figures, reference numeral 1 denotes a synthetic resin container body (one member forming a sealed container) in which foods and the like are sealed, and 2 denotes a synthetic resin container for sealing an upper opening thereof. A lid (the other member forming a sealed container) made of a film. The lid 2 is attached or welded to an opening edge (joined portion) of the container main body 1 after storing the food in the container main body 1. .

Reference numeral 3 denotes a holding table fixed on a transfer device such as a conveyor 9 (see FIG. 6) for holding the outer bottom portion of the container body 1, and is horizontally moved in accordance with the intermittent transfer operation of the conveyor 9. It is configured to move.

In FIG. 1, a pressing head 4 having a substantially inverted T-shaped cross section and a circular end surface is provided on the upper portion of the lid 2 so as to be vertically movable by a power source such as an air cylinder. When the container body 1 and its lid 2 arrive at the lower part of the pressing head 4 and stop, the pressing head 4 descends, and a position (downward death) where the upper surface (detected surface) of the lid 2 is slightly pushed down. After stopping at (point) (see FIG. 2), it rises and returns to the initial position (top dead center) and stops.

On the downstream side of the pressing head 4, an opening 7 is formed in a portion (lower end surface) facing the upper surface of the lid 2, and a rubber bellows 5 is attached to a peripheral portion of the opening 7. Cylindrical chamber (housing) 6 is provided so as to be able to move up and down by reducing the power of an air cylinder or the like.

The inside of the chamber 6 has a magnetic material 10
A float 13 made of a synthetic resin to which is adhered arrives vertically movable, and a sponge member 1 having sufficient elasticity is provided between the upper end of the float 13 and the inside of the upper surface of the chamber 6.
1 is attached.

At the upper end of the chamber 6, a magnetic sensor (dimension measuring sensor) 8 for measuring the approach / separation dimension of the magnetic body 10, that is, the vertical movement dimension of the float 13, is fixed.

A hole 12 is formed in a part of the chamber 6 for communicating the inside and the outside of the chamber 6, and the hole 12 is opened and closed for vacuum breaking through a pipe (not shown). It is connected to a valve (not shown).

When the container body 1 whose lid 2 is pressed from above by the pressing head 4 arrives below the chamber 6 and stops, the lower end of the float 13 is The chamber 6 descends until it makes light contact with the upper surface.

Then, the magnetic body 10 approaches the magnetic sensor 8 while compressing the sponge member 11 slightly upward, and the dimensions of the magnetic sensor 8 and the magnetic body 10 are measured. Is measured means that the dimension from the upper surface of the lid 2 to the magnetic sensor 8 is measured.

At this time, the opening / closing valve is open, and the inside of the chamber 6 is at P0 as at the atmospheric pressure.

In this case, as shown in FIG. 3, a predetermined dimension from the magnetic sensor 8 to the upper surface of the lid 2 in a state where the pressing head 4 does not press the lid 2 is set to H0. Is set so that the dimension actually measured after pressing the lid 2 is H1, and if H1-H0 is within the predetermined value α, the container is determined to be good.

When the container body 1 and the lid 2 are not sufficiently adhered to each other, when the lid 2 is pressed downward by the pressing head 4, the lid 2 is depressed downward. ,
The dimension H1 becomes large.

Therefore, when H1−H0> α, the dimension H1 is larger than the predetermined dimension H0 + α, and the container body 1 and the lid 2 are not sufficiently adhered to each other, resulting in poor sealing. Is judged to be present, and is conveyed to the right as it is to be processed as a defective product.

It should be noted that even when the container body 1 and the lid 2 are sufficiently adhered to each other, the lid 2 is not
When the lid 2 is pressed downward, the lid 2 is slightly depressed downward, but the depressed dimension is extremely small as compared with the case where the container body 1 and the lid 2 are not sufficiently adhered. .

Therefore, if H1−H0 ≦ α, the product does not have a sealing failure in the first step, and the chamber 6 is further lowered as shown in FIG. 1 and a bellows 5 in contact with the upper surface of the lid 2
Is pressed while pressing the upper surface of the lid 2.

At this time, the opening / closing valve is closed, and the inside of the chamber 6 is in a closed state. The pressure in the chamber 6 rises in inverse proportion to the contraction size of the bellows 5, and the pressure increases from the atmospheric pressure P0. The pressure is raised to P1, and the lid 2 is pressed by the pressure.

Further, since the lower end of the float 13 comes into contact with the upper surface of the lid 2 and the chamber 6 descends,
The lid 2 is further pressed downward by the elastic force of the sponge member 11.

Here, before the downward pressure is applied, when the pressure in the chamber 6 is the atmospheric pressure P0,
A predetermined dimension from the magnetic sensor 8 to the upper surface of the lid 2 is h
0, the measurement size when the pressure in the chamber 6 rises and the float 13 presses the upper surface of the lid 2 downward is defined as h.
As 1, the container is determined to be good if h1-h0 is within the predetermined value β.

When the container body 1 and the lid 2 are not sufficiently adhered to each other, as described above, the lid 2 is moved downward by the increased air pressure P1 and the elastic force of the sponge member 11. When pressed, it is depressed downward, so that the dimension h1 becomes large.

Therefore, when the container body 1 and the lid 2 are not sufficiently in close contact with each other, the air in the container body 1 can be discharged to the outside from the non-contact portion with the lid 2. When the pressure in the chamber 6 rises and is further pressed by the resilience of the sponge member 11, the lid 2 is slightly depressed toward the container body 1 and h1-h0> β, and the dimension h1 Is larger than a predetermined dimension h0 + β, and it is determined that a sealing failure has occurred. In this case as well, the defective product is determined and processed.

When the container body 1 and the lid 2 are sufficiently in close contact with each other, the air in the container body 1 cannot be discharged to the outside from the portion in close contact with the lid 2. The pressure in the chamber 6 increases, and the sponge member 11
Even when the cover 2 is pressed by the resilience, the size of the cover 2 depressed toward the container body 1 becomes extremely small and h1−h0 ≦ β, and the product does not have a sealing failure even in the second step. , And is determined to be good and processed.

After the pass / fail judgment is made, the open / close valve is opened, and the pressure inside the chamber 6 becomes the atmospheric pressure P0, so that the lid 2 can be easily moved from the bellows 5 of the chamber 6. You will be separated.

In the present embodiment, in the second step, the sponge member 11 is pressed through the high air pressure P1 in the chamber 6 and the float 13 to press the lid 2 downward.
However, the resilience of the sponge member 11 is used in an auxiliary manner, and a defect can be detected only by a high air pressure in the chamber 6.

【The invention's effect】

In the first aspect of the present invention, the housing is deformed so as to reduce its volume by bringing the opening of the housing into close contact with the surface to be detected so as to reduce the volume thereof, thereby increasing the internal pressure. When the surface to be detected is depressed, the depressed dimension is measured, and when the depressed dimension is larger than a predetermined dimension, it is determined that there is a sealing failure in the sealed container. Since the air pressure in the housing is increased without supplying air, a step of supplying air into the housing becomes unnecessary.

In the second invention, a bellows made of a soft member is attached to the opening of the housing, and the bellows of the housing is brought into close contact with the surface to be detected of the sealed container and pressed to compress the bellows. Since the internal pressure is increased, the pressure inside the housing is increased only by compressing the bellows without supplying high-pressure air into the housing, so that a step of supplying air into the housing is unnecessary. Becomes

In the third invention, for example, when a plurality of members are not sufficiently joined, when the surface to be detected is pressed mechanically, the surface to be detected is greatly depressed by the pressing. By performing the measurement, it is possible to determine that there is a sealing failure in the sealed container without pressing the housing to perform the measurement.

Therefore, it is possible to detect the sealing failure very easily in a short time.

When the lid is simply placed on the container main body or when the lid is not present, it can be immediately detected, and the contents of the container main body are blown off to contaminate the surrounding environment.
The housing does not come into contact with the contents of the container body and does not stain the housing.

The effect of the fourth invention is substantially the same as that of the first invention.

The effect of the fifth invention is substantially the same as that of the third invention.

[Brief description of the drawings]

FIG. 1 is a partially enlarged front view showing a first stage of a first step in one embodiment of the present invention.

FIG. 2 is a partially enlarged front view showing a latter stage of a first step in the embodiment of the present invention.

FIG. 3 is a partial cross-sectional enlarged front view showing a stage before a second step in the embodiment of the present invention.

FIG. 4 is an enlarged partial cross-sectional front view showing a second stage of a second step in the embodiment of the present invention.

FIG. 5 is a flowchart of an embodiment of the present invention.

FIG. 6 is an overall front view of the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container main body 2 Lid 3 Holder 4 Pressing head 5 Bellows 6 Chamber (housing) 7 Opening 8 Magnetic sensor 9 Conveyor 10 Magnetic body 11 Sponge member 12 Through hole 13 Float

Claims (5)

[Claims] 1. A method for inspecting a sealing failure by applying pressure to a surface to be detected of a hermetically sealed container to which a plurality of members are joined and not including the joint, and measuring a depressed dimension of the surface to be detected. In at least a part of the deformable casing, an opening is formed in a portion facing the detection surface of the sealed container, and a measuring means for measuring a distance to the detection surface is provided inside, When the opening of the housing is brought into close contact with the surface to be detected and pressed to deform the housing so as to reduce its volume and raise the internal air pressure, and when the pressure increases, the surface to be detected is depressed. A method of inspecting the hermetically sealed container to determine whether or not the hermetically sealed container is defective in sealing if the measured indentation size is larger than a predetermined size. 2. A bellows made of a soft member is attached to an opening of the housing, and the bellows of the housing is brought into close contact with the detection surface of the sealed container and pressed, and the bellows is compressed to reduce the internal pressure. When the detected surface is depressed due to the increase in the pressure, the depressed dimension is measured, and when the depressed dimension is larger than a predetermined dimension, it is determined that there is a poor sealing in the sealed container. 2. The method for inspecting sealing failure of a sealed container according to 1. 3. In a process before pressing the housing against the surface to be detected of the sealed container, the surface to be detected is mechanically pressed, and when the surface to be detected is depressed by the pressing, the depressed dimension is measured. The defective sealing of the sealed container according to claim 1 or 2, wherein when the depressed size is larger than a predetermined size, it is determined that the sealed container has defective sealing without pressing and measuring the housing. Inspection methods. 4. An apparatus for inspecting sealing failure by applying pressure to a surface to be detected of a hermetically sealed container to which a plurality of members are joined and not including the joint, and measuring a depressed dimension of the surface to be detected. In the above, an opening is formed in a portion of the sealed container facing the surface to be detected, and at least a part of the housing is deformable; and a measuring means mounted inside the housing and measuring a distance to the surface to be detected. And pressing means for pressing the housing by bringing its opening into close contact with the surface to be detected, and pressing the housing in close contact with the surface to be detected so as to reduce the volume of the housing. When the surface to be detected is depressed due to the increase in the internal pressure due to the deformation, the depressed size is measured, and when the depressed size is larger than a predetermined size, the sealed container is not properly sealed. Judge that exists Sealing failure inspection apparatus of a sealed container, characterized in that. 5. A method according to claim 1, further comprising: means for mechanically pressing said surface to be detected, wherein said means is provided in a step prior to pressing said housing against said surface to be detected of said sealed container.
5. The measuring device according to claim 4, wherein the measuring unit measures the depression size, and when the depression size is larger than a predetermined size, it is determined that there is a sealing failure in the sealed container without pressing and measuring the housing. Insufficient sealing container inspection device.