JPS6028729B2 - Gas replacement method and device for filling packaging - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas replacement method and apparatus for filling packaging.

In general, in filling packaging, in which the object to be packaged is filled into a container and then covered with a cover for sealed packaging, when the object to be packaged is food, etc., it is confined inside the package to prevent deterioration due to oxidation. The air used in the process is replaced with an inert gas such as nitrogen gas.

By the way, the conventional method of replacing gas was to evacuate the inside of the package in advance using a vacuum diagram, but in this method, the liquid to be filled inside the package was When the temperature is high, the pressure inside the vacuum chamber decreases and the liquid boils, making it difficult to seal the package. The present invention has been made in view of these problems, and its purpose is to provide a method and apparatus for performing gas replacement under approximately atmospheric pressure without relying on vacuum evacuation. The first invention of the present application introduces a container filled with contents in advance into a gas replacement chamber, and forms a jet flow of replacement gas on the top surface of the container,
In a gas replacement method for filling packaging in which the air in the container is replaced with replacement gas and then the container is sealed with a cover film, the replacement gas is injected obliquely onto the upper surface of the container toward the upstream side in the direction of travel of the container. The air replaced by the replacement gas is discharged from the gas replacement chamber along with a part of the replacement gas on the upstream side in the direction of travel than the injection position of the replacement gas, and the gas replacement chamber is filled with the gas replacement chamber. The container is configured to be covered with the cover film indoors, and the container taken out from the exchange chamber and the cover film are sealed.

The gas exchange device for filling packaging according to the second invention of the present application includes a housing that is disposed on a transfer path of a container and forms a gas exchange chamber in the upper part of the container, and a housing that is disposed within the housing. A gas injection nozzle is provided on the upper surface of the container and injects replacement gas obliquely toward the upstream side in the traveling direction of the container, and a gas injection nozzle is provided on the upstream side within the housing to define an exhaust chamber within the housing. a sealing device provided close to the cover film inlet of the housing, and a guide means disposed within the gas exchange chamber for covering the cover film over the top surface of the container. . DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the gas replacement method and apparatus according to the present invention will be described below with reference to the drawings.

1 and 2, the gas replacement device 1 of this embodiment has an upper wall 20, a front wall 21, a rear wall 22, and both side walls 2.
3 and 24, and a gas exchange chamber C. It has a housing 2 defining a . A partition plate 3 is fixed within the housing 2 and forms an exhaust chamber C2 on the upstream side (left side in FIG. 1) thereof.
Two injection pipes 4, 4a are provided in the center of the housing, extending between both side walls 23, 24. A large number of gas injection nozzles 40 are arranged at equal intervals in the longitudinal direction of the gas injection pipe 4 so that gas can be injected almost evenly over the entire width in the width direction of the housing, that is, in the width direction of the rows of containers to be fed. It is provided diagonally upstream on the top surface of the container. On the other hand, since the gas injection pipe 4a is used exclusively to compensate for gas leakage on the side of the exchange chamber, the side wall 2
3 and 24, a large number of gas injection/throwing holes 40a are provided on the upper surface of the container, facing diagonally upstream. The gas injection pipes 4 and 4a can each be independently supplied with the combined pressure of the necessary inert gas, that is, the replacement gas, so that the amount of replacement gas consumed can be saved. An inlet 25 for the cover film f is formed in the upper part of the front wall 21.

An inlet 25 is defined by the upper wall 20 and the partition plate 3.
In the introduction passage P for the cover film following the gas exchange chamber C, a sealing device 5 for preventing communication between the inside and the outside air is provided over the entire width of the introduction passage. This sealing device is composed of a guide plate 50 fixed to the upper side of the partition plate 3, and a pressure plate 51 fixed to the lower surface of the upper wall of the housing to press the cover film f against the guide plate. On the downstream side within the housing 2, a pair of guide rollers 6, 6a constituting guide means for the cover film are rotatably provided across both side walls.

The guide rollers 6, 6a function to make the cover film f introduced into the gas exchange chamber C through the introduction port 25 and the introduction passage closely follow the upper surface of the container exiting the gas exchange chamber. A guide plate 7 is provided on the outer lower side of the front wall 21 and extends along the upper surface of the container. An exhaust duct 8 is provided on the side wall 23 of the housing at a position facing the exhaust chamber C2, and the gas in the exhaust chamber can be exhausted through the exhaust duct. Next, the operation of this gas replacement device will be explained.

In this operation explanation, a case will be explained in which the container R is formed on a continuous container film F by a known method and moves as the container film F moves. Replacement room C
, from the injection nozzles 40, 40a provided in the gas injection pipes 4, 4a, a replacement gas such as nitrogen gas is continuously injected diagonally downward and upstream in the direction of entry of the film F, and the exhaust duct. The gas in the exhaust chamber is exhausted.

Therefore, in the displacement chamber C, a relatively high-speed jet flow A of displacement gas is formed from the injection nozzle to the exhaust chamber C2 after passing under the lower portion 30 of the partition wall 3. Under such conditions, when the container R is formed and the film F filled with the contents M in the container enters into contact with the lower side of the housing 2 in the direction of the arrow X and closes, the entry of the film In particular, the air introduced into the displacement chamber C as the container R enters is restricted to a minimum by the guide plate 7, but the air in the space S above the contents M in the container is prevented from entering. Can not.

However, when the film F passes under the gas flow of the displacement gas, the air in the space is completely replaced by the displacement gas by the action of the gas flow until the container reaches directly below the gas injection pipe. The air in the space S or on the top surface of the film is caught up in the gas flow and reaches the exhaust chamber C2,
From there it is exhausted via an exhaust duct. Next, when the film comes down to the guide roller, the cover film f is covered over the film F, and when it goes out into the replacement chamber, it comes out with the cover film f covered on top.

Then, the cover film f is tightly attached to the film F' from the sealing device 10 provided immediately downstream of the gas replacement device 1, and the container is sealed by the cover film f. As described above, according to the gas replacement method of the present invention, it is possible to obtain a gas replacement device that has a simple structure, is easy to operate, and is suitable for filling and packaging high-temperature liquids, and is also capable of replacing even relatively shallow and wide-mouthed containers. It can be sealed with a cover film without escaping gas into the atmosphere, and does not harm the surrounding environment.

In the above embodiment, the containers are continuously formed on the film and moved together with the film, but as shown in FIG. A layered structure may also be used.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a gas replacement apparatus according to the present invention, FIG. 2 is a cross-sectional view taken along the line 0--river in FIG. 1, and FIG. 3 is a diagram showing a modification of the container conveying method. 1: Gas replacement device, 2: Housing, 3: Partition wall, 4, 4
a: Gas injection pipe, 40, 40a: Gas injection nozzle, 5:
Sealing device, 6, 6a: Guide means, C: Gas replacement chamber,
C2: Exhaust chamber, F: Film, f: Cover film, M
: Contents, R: Container. Figure 2 Figure 3 Figure 1

Claims (1)

[Scope of Claims] 1. A container filled with contents in advance is introduced into a gas replacement chamber, and a jet flow of replacement gas is formed on the upper surface of the container, and the air in the container is replaced with the replacement gas. In a gas replacement method for filling packaging in which the container is sealed with a cover film, the replacement gas is injected obliquely toward the upstream side in the direction of travel of the container onto the top surface of the container, and the air replaced by the replacement gas is replaced by the replacement gas. is discharged from the gas exchange chamber on the upstream side in the traveling direction from the injection position of the displacement gas, and the gas-replaced container is covered with the cover film in the gas exchange chamber, and the container is taken out from the exchange chamber. 1. A gas replacement method in filling packaging, characterized in that the container and the cover film are sealed tightly. 2. A housing disposed on the transfer path of the container and forming a gas exchange chamber in the upper part of the container; a gas injection nozzle that injects replacement gas obliquely toward the side; a partition wall disposed on the upstream side of the housing and defining an exhaust chamber within the housing; 1. A gas replacement device for filling and packaging, comprising: a sealing device provided in the gas replacement chamber; and a guide means disposed within the gas replacement chamber for covering the top surface of the container with the cover film.