JP2754751B2 - Degassing valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a degassing portion of a sealed package for filling contents that generate a small amount of gas during storage of roasted coffee beans or the like. The present invention relates to a gas vent valve that is closed and attached and is used to escape the gas outside the package when the gas is filled in the package. More specifically, the gas escape passage is filled with a liquid sealant such as silicone oil. In addition, the present invention relates to a gas vent valve in which a gas escape passage is configured as a dry passage.

[Conventional technology]

Conventionally, as a vent valve, a valve film is disposed so as to form a gap between the base film and one surface of a base film having a through hole so as to cover the through hole and allow gas to escape from the through hole to the outside. In addition, it is known that the gap is configured as a gas escape passage (Japanese Patent Application Laid-Open No. 56-32244).
JP, JP-A-60-57069, JP-A-63-6278, JP-A-63
-6279 publication).

However, these conventional vent valves are difficult to operate properly when the gas escape passage is in a dry state. In particular, gas is generated in the package, the internal pressure increases, the valve film opens, and the gas passes through the passage. When the valve film resiliently recovers and closes the through hole of the base film again after it escapes to the outside, the valve film is restored to its original state and the valve film does not adhere to the base film, and the valve film and the base film A slight gap may still be left between the film and the film. Therefore, the airtightness at the time of closing is insufficient, and air may flow into the package from the outside through the passage.

For this reason, for the purpose of improving the airtightness of the valve and smoothly opening and closing the gas escape passage, the passage is filled with a liquid sealant such as silicone oil (Japanese Patent Publication No. 59-1984). -29501, JP-A-63
-152551).

[Problems to be solved by the invention]

However, when a liquid sealant such as silicone oil is supplied to the gas escape passage in this way, the sealant penetrates into the package through the gas vent of the package through the through hole (gas inflow hole) of the base film, and The problem of contaminating the product arises.
In addition, there is a problem that the sealant flows out from the passage to the outside and stains the outer surface of the package to which the valve is attached.

For this reason, there is a demand for a gas venting valve in which the valve operates smoothly without using a liquid sealing agent and the gas escape passage surely maintains airtightness.

The present invention has been made in order to meet the above-mentioned demand, and the gas escape passage maintains a sufficient airtightness without using a liquid sealant. It is an object of the present invention to provide a gas venting valve that opens the valve quickly and surely to allow gas to escape to the outside, and that closes the valve immediately after gas is discharged to hermetically close the passage.

[Means for solving the problem]

In order to achieve the above object, the present invention provides a sealed package in which a content product that generates a small amount of gas during storage is filled and a gas vent portion through which gas generated from the content product can pass is formed. In a gas vent valve attached to cover the vent portion, a gas inflow hole communicating with the gas vent portion is formed, and the gas inflow hole is formed on the surface of a plastic base film attached to the sealed package. Laminate a plastic sealing film to be closed, and bond the opposite side edges of the base film and the sealing film to each other,
A pressing valve body formed by folding a single plastic film is disposed such that the bent end portion thereof comes into contact with the sealing film, and the base end portion of the valve body is bonded to the sealing film with the bonding edge. Adhering to one of the side edges, and covering the valve body, the opposite side edges of the control film disposed in contact with the two sides are bonded to the bonded side edges, When gas is generated in the package and the internal pressure increases, the internal pressure causes the sealing film to lift up against the pressing force from the valve body side, thereby forming a gap between the sealing film and the base film formed by the gas. In addition to being configured as an escape passage, the passage is a dry passage not filled with a liquid sealant such as silicone oil.

(Operation)

The degassing valve of the present invention is mounted and used by covering the degassing portion of the sealed package, and at the time of use, gas is generated from the contents filled in the sealed package,
When the internal pressure rises, gas flows from the gas vent to the gas inlet of the vent valve, presses the sealing film and opens it, forming a gap (gas escape passage) between the sealing film and the base film. And escape to the outside through the gap,
After the gas is discharged in this way, the passage is closed in an airtight manner.

That is, the degassing valve of the present invention is obtained by laminating a plastic sealing film that closes the gas inflow hole on the surface of a plastic base film, and bonding the base film and the sealing film to opposite side edges of the base film and the sealing film. At the same time, the pressing valve body formed by folding one plastic film is disposed so that the bent end portion thereof comes into contact with the sealing film, and the base end edge of the valve body is formed of the sealing film. The control film, which is adhered to one of the bonded side edges and covers the valve body, and the opposing side edges of the control film disposed in contact therewith, are bonded to the bonded side edges. The film and the valve element are always in close contact with each other. In this case, the plastic sealing film is first in close contact with the base film, and the bending end portion of the pressing valve body formed by folding one plastic film against the sealing film is pressed by the restoring elastic force. By doing so, the sealing film is securely in contact with the base film in combination with the elasticity of the plastic forming the film, and the control film controls the opening of the pressing valve by controlling the pressing valve by pressing the pressing valve. However, since the pressing force against the sealing film by the bent end portion of the pressing valve body is securely held, no gap is always generated between the base film and the sealing film, and the gas inflow hole is securely closed. Have been.

In such a state, when the internal pressure of the package becomes equal to or higher than a predetermined pressure, the gas in the package lifts the sealing film against the pressing force, and forms a gap between the sealing film and the base film. When the gas escapes and the internal pressure of the package decreases due to the escape of the gas, the elastic restoring force of the control film, the valve body, and the sealing film immediately acts, and in this case, since the sealing film is disposed, the valve body While the pressing force from is equalized by the sealing film, the strong pressing force acts on the base film in combination with the elasticity of the sealing film, so that the gap is immediately closed,
Even if there is no liquid sheet material in the passage, the passage is reliably airtightly closed.

In the case where the sealing film is not provided, the valve body is formed by folding one film, and has a restoring force, so that the bent portion side is slightly floating compared to the tip side of the bent portion, For this reason, the passage is not completely closed, and the pressing force and the adhesion to the base film are inferior to those without the sealing film, so that the passage is often not airtightly closed when the valve is closed. If the passage is not filled with a liquid sealant such as oil, a good valve function cannot be exhibited.

However, in the present invention, as described above, the valve has a good valve function, and the airtightness of the passage when the valve is closed is sufficiently ensured even without supplying the liquid sealing agent. Since no liquid sealant is used, there is no inconvenience such as contamination of the contents and contamination of the package.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

〔Example〕

1 shows a degassing valve according to one embodiment of the present invention. The degassing valve 1 is composed of a base film 2, a sealing film 3, a valve body 4, and a control film 5. I have.

The base film 2 is bonded to the hermetically sealed packaging bag so as to cover the degassing portion. The base film 2 is formed in a substantially square shape with rounded corners made of plastic. Circular hole (gas inflow hole) communicating with
6, and an adhesive layer 7 is formed on the entire back surface of the base film 2.

The sealing film 3 is made of plastic and has substantially the same size and the same shape as the above-mentioned base film 2. Both side edges 8,8 are bonded 10,10 including the rounded four corners 9,9,9,9 of the sealing film 3, so that the tips of the other unbonded both side edges 11,11 are provided. Are not protruding outward from both ends 8a, 8a, 8a, 8a of the bonding side edges 8, 8.

The sealing film 3 uses a relatively thin synthetic resin film such as Saran (PVDC, polyvinylidene fluoride) having a thickness of, for example, 2 to 10 μm. Since it has good adhesion to the base film, it is effective in preventing gas from entering from the outside. Further, in this case, if the surface of the sealing film 3 on the side of the base film 2 is subjected to a satin finish, the escape of gas from the inside of the package becomes easier.

Further, the valve element 4 is disposed on the sealing film 3 and has a configuration in which a single plastic square film is folded while being shifted from its center line, and the base edge 12 thereof is closed. In addition to being integrally bonded to one of the adhesive portions 10 of the film 3, the bent portion 13 is in contact with the sealing film 3 and presses the sealing film 3 by its elastic force.

The control film 5 is made of plastic and has approximately the same size and the same shape as the base and the sealing films 2 and 3.
The base film 12 is integrally bonded to the base edge 12 and the other bonding portion 10 of the sealing film 3, and the back surface of the control film 5 is in close contact with the valve body 4.

The thickness of the plastic film forming the valve body 4 is not particularly limited, but may be 5 to 50 μm, and the thickness of the control film 5 may be, for example, 50 to 250 μm.
μm.

For the above-mentioned bonding, means such as bonding using a pressure-sensitive adhesive and thermal bonding can be adopted.

The vent valve 1 is used by bonding the adhesive layer 7 of the base film 2 to a hermetically sealed packaging bag with the vent portion and the circular hole 6 connected to each other. Thus, the sealing film 3 normally closes the circular hole 6 and the hermetically sealed packaging bag is completely sealed. To explain this point in more detail, the side edges of the base film 2, the sealing film 3, the valve body 4, and the control film 5 are adhered to each other and adhere to each other. In this case, the valve body 4 is made of one sheet. Since it is formed by folding the plastic film, it has an elastic restoring force and exerts a pressing force outward. However, the outer surface of the valve body 4 comes into contact with the control film 5 and is pressed. Therefore, the bent portion 13 presses the sealing film 3 with a strong force, so that the sealing film 3 receives the pressing force and presses the base film 2. And since the sealing film 3 is formed from one sheet of flat film, the pressing force from the valve body 4 is evenly transmitted to the base film 2, so that the sealing film 3 strongly adheres to the entire surface of the base film 2, Inflow of air from the air is reliably blocked.

In this state, when the contents filled in the packaging bag generate gas and the internal pressure of the packaging bag becomes high, this high-pressure gas passes through the gas vent of the packaging bag and is blocked from the circular hole 6 of the base film 2. The film 3 is pressed against the pressing force of the valve body 4 to form a gap between the sealing film 3 and the base film 2, and the gap is used as a gas escape passage.
It escapes from the unbonded both-ends edge portions 11 and 11 that have been released to prevent an abnormal increase in the internal pressure of the packaging bag.

When the gas in the packaging bag escapes in this manner, the gap is immediately closed by the restoring action of the sealing film 3, the valve element 4, and the control film 5, and the sealing film 3 comes into close contact with the base film 2. Even if there is no liquid sealant such as silicone oil in the (passage), the passage is securely closed,
The inflow of air from the outside is completely shut off, thereby preventing deterioration of the contents.

Therefore, since the gas vent valve 1 does not use a liquid sealing agent, the contents are not contaminated by the liquid sealing agent and the outer surface of the packaging bag is not stained.

According to the degassing valve 1 described above, the non-adhered both end edge portions are provided.
11 and 11 do not protrude outward from both ends 8a, 8a, 8a, 8a of both side edges 8, 8, so that there is no possibility that a finger or the like may be caught, especially when high-pressure gas escapes outside. The unbonded end edges 11 and 11 swell, but even in such a case, there is no possibility that a finger or the like may be caught.
Accidents such as dropping the sealing film 3 or the control film 5 by hooking a finger or the like on 11, 11 are unlikely to occur.

In the present invention, as the degassing portion of the sealed package,
There are hole-shaped ones such as circular holes and slit-shaped ones such as linear slits.When filling granular contents, it is preferable to form a plurality of linear slits parallel to each other. According to the method, the gas generated from the contents of the packaging bag smoothly passes through the slit, but the passage of the granular contents from the slit is reliably blocked.

Further, in the above-described embodiment, the shape of the film is a square shape with rounded four corners, but the film may be formed in an appropriate shape, for example, formed in a circular shape, and other configurations are also included in the gist of the present invention. Various changes may be made without departing from the scope.

〔The invention's effect〕

As described above, the degassing valve of the present invention effectively operates the valve function without supplying a liquid sealant such as silicone oil to the gas escape passage, and ensures that the high-pressure gas in the package is externally provided. After the gas is discharged, the sealing film strongly adheres to the base film to completely close the passage, thereby reliably blocking the inflow of air from the outside. Therefore,
Since no liquid sealant is used, there is no contamination of the contents and the outer surface of the package.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present invention, and FIG.
FIG. 2 is an enlarged sectional view taken along the line II-II in FIG. 1 ... vent valve, 22 ... base film, 3 ... sealing film, 4 ... press valve body, 5 ... control film, 6 ...
... gas inlet holes, 8 ... side edges.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-56-32244 (JP, A) JP-A-60-57069 (JP, A) JP-A-63-6278 (JP, A) JP-A 63-278 152551 (JP, A) JP 59-29501 (JP, B2)

Claims (1)

(57) [Claims] 1. A sealed package body filled with a content that generates a small amount of gas during storage and formed with a gas release portion through which gas generated from the content can pass is covered with the gas release portion. In the attached gas vent valve, a gas inlet hole communicating with the gas vent portion is formed, and a plastic base film that closes the gas inlet hole is provided on the surface of the plastic base film attached to the sealed package. The sealing film is laminated, and the opposite side edges of the base film and the sealing film are adhered to each other, and the pressing valve body formed by folding one piece of plastic film is closed at the bending point. The valve body is disposed so as to be in contact with the film, the base end of the valve body is bonded to one of the bonded side edges of the sealing film, and covers the valve body, and is provided in contact with the valve body. System The opposite side edges of the film are bonded to the bonded side edges, and when gas is generated in the package and the internal pressure increases, the sealing film is moved from the valve body side by the internal pressure. The gap between the sealing film and the base film formed by lifting against the pressing force of the base film is configured as a gas escape passage,
A gas vent valve, wherein the passage is a dry passage not filled with a liquid sealant such as silicone oil.