KR100200160B1 - Method of foaming container perspective glass by the process of blow molding - Google Patents

Abstract

1. The technical field of the invention described in the claims

A sight window molding method for a container produced by a blow molding method.

2. The technical problem to be solved by the invention

Conventionally, by making a container first, and using a method of coupling the see-through window to the container in a completely molded state, not only is it difficult to achieve perfect coupling between the see-through window and the container, but also has a closed end that increases the process of joining the see-through window to the container.

3. Summary of the solution of the invention

The present invention allows the see-through window fixed to the mold inner wall to be combined with the container during one blow process, but the flyson is not in contact with the closed hollow portion of the see-through window formed by the concave portion, and the container is heat-sealed only outside. It is to allow the see-through window and the container to penetrate by cutting the inflation portion of the molded container to be molded.

4. Important uses of the invention

For forming see-through windows in containers filled with liquids.

Description

Method for forming sight glass of a container produced by blow molding method

1 is a schematic longitudinal sectional view of a mold apparatus for showing the steps for forming a see-through window in a container.

(a) is a state where the sight glass is fixed to the mold inner wall in an open state.

(b) extrudes the parison between the open molds.

(c) is a state in which the container is molded by closing the mold and blowing air into the mold.

(d) is a state where the fly hand is fused to the side of the viewing window while covering the viewing window.

(e) a state in which the mold is opened after the container is molded, and an expanded portion is formed in the container ejected from the mold.

Figure 2 is a longitudinal cross-sectional view for showing the state of use of the container filled with the contents after cutting the expansion and projections formed inside the container.

3 is a container produced by the manufacturing method of the present invention.

* Explanation of symbols for main parts of the drawings

10: container 11: handle

12: entrance 20: viewing window

21: projection 22: hollow part

23: recess 24: scale

30: expansion portion 40: fusion portion

A: mold B: installation

C: Extruder D: Parison

The present invention relates to forming a see-through window in a synthetic resin container for filling a liquid, and more particularly, to a method for forming a see-through window in a container manufactured by a blow molding method.

In the case of containers filled with liquids, especially metered petroleum containers, it is necessary to confirm the exact amount of filling from the outside. In particular, in the case of opaque oil barrels made of synthetic resin, a sight glass to check the contents by government policy must be formed in the container. However, it is usually not easy to manufacture opaque containers and transparent viewing windows by a general blow molding process.

In other words, the manufacturing method of the container by the general blow is to close the mold with the fly hand between the open blow, and to blow the air into the fly hand to form the container by the inner wall form of the mold, most skilled in the art If the sight window is attached to the mold's inner wall and the opaque material flyson is blown with air, the sight window is fused and covered completely by the frayson.

Therefore, a container having a see-through window produced by combining the transparent see-through window and the container integrally in one blow process has not been used yet. However, Japanese Patent Laid-Open No. 63-183815 discloses a method of forming a tank by molding a hollow tank material and cutting a closed wall of a level shank portion in order to check the water level of the contents, and Japanese Unexamined Patent Application Publication No. 5-24100 In the blow molding method, there is also known a method of removing the transparent layer after the blow molding by using the outer side as the opaque layer and the inner side as the transparent layer, and the former is provided on the upper wall of the tank body. Is a method of manufacturing a synthetic resin fuel tank which is integrally protruded into the oil level check container received inside the tank body by using an integrally formed mold having a carbide corresponding to the upper half and the lower half of the electric tank body. A step of cutting off the closed end wall of the inner stage immediately after opening the gas as an oil inlet, and comprising a slight amount thereof. A method for manufacturing a fuel tank has been devised. The latter uses an opaque layer on the outside and a transparent or semi-transparent layer on the inside to protrude the visible barrel (visible window) to the outside to form a two-layer blow molded article. A broach forming method is devised, which comprises a step and a step of removing an opaque layer of an electric visual communication box. However, the above methods are those in which the see-through window is formed after the brow molding, which has a large difference in the manufacturing procedure from the present patent.

As such, until now, only a method of manufacturing a container by a blow molding method to separate it from a mold and then combining the viewing window with the container in a completely molded state is used. You will have a need for a manufacturing process.

That is, the container in which the viewing window is formed by the same method as the former may be screwed by forming a screw thread in the container and the viewing window, or after cutting the viewing window coupling part formed in advance in the container, fitting the viewing window to the viewing window coupling part and heat-sealing it. The method and the like are used, but the above methods are a method of combining the see-through window in a container that has already been completely molded, and thus, in order to combine the see-through window with the container, a preliminary work step for combining the see-through window with the container is required. The disadvantage of having to cut the part of the container for a part, and the molded container, even if the sight window is screwed or heat-sealed, the volume changes due to the change of temperature, resulting in a gap in the joint part or the fusion part. The disadvantage is that

The latter not only has to repeat the brower operation twice, but also has a waste that requires a lot of material.

In order to solve the many disadvantages of the related art, the present inventors have experimented with various methods to see that the concave shape of the window is covered by the flyson. Since it does not reach the window of the hollow, only the outside part of the hollow part is in contact with the heat-sealing, so that the see-through window is molded in a single mold, thereby completely eliminating the disadvantages of the containers having the conventional see-through window. It was.

Referring to the present invention in detail the see-through window forming process by the accompanying drawings as follows.

Figures 1 (a) to (e) are schematic longitudinal cross-sectional views of the mold apparatus for the purpose of showing each step for forming a see-through window in a container.

First, while the mold A is in the open position, the shape of the cross section prepared in advance at the position where the mold A inner wall viewing window is formed is c-shaped, and the concave portion 23 opens the viewing window 20 in which the protrusion 21 is formed. Adhesion is directed toward the inside of the mold (A).

At this time, the material of the see-through window 20 should be heat-sealed with the container, and the hollow part 22 should be formed so that air is not leaked by the recess 23.

Means for fixing to the mold A should be formed on the outer surface of the see-through window 20. For example, the protrusion 21 may be mentioned. The protrusion 21 is inserted into and fixed to an insertion hole (not shown) formed on the inner wall of the mold (A). After the blow process, the container 10 is removed from the mold (A) and removed.

The second step is the parison D being extruded by the extruder C between the open molds A.

The third step is a step in which the open mold A is closed, and the container 10 is molded by blowing air into the mold by the duct B.

The fourth step is a step in which the parison D is fused with the outer circumferential surface of the recess 23 while surrounding the recess 23 of the viewing window 20.

At this time, Parison (D) is about 4kg / While expanding by being pushed by the air pressure of the close contact with the inner wall of the mold (A) is formed into a container (10). However, in the case of the see-through window 20 fixed to the mold inner wall, it is in close contact with the outer circumferential surface of the recess 23 and is approximately 200. Melt by the temperature of the flyson (D) of the degree is fused to each other, but since the air pressure inherent in the concave portion 23, that is, the hollow portion 22 is higher than the air pressure to be blown, the flyson (D) is Although pushed to a certain extent, the inner surface of the see-through window 20 is not adhered to each other and is molded in a state where power is balanced.

The fly hand D, which has been pushed into the recess 23, is pushed out of the recess 23 by the expanded air in the hollow 22 when the container 10 is released from the mold. 30 will be formed.

The fifth step is the step in which the mold A is opened after the container 10 is molded. Since the parison D is not completely cooled and hardened, the container 10 is released into the mold and hollowed out at the same time. As the flyson D pushed into the part 22 protrudes out of the recess 23 to form the inflation part 30, the worker inflates with a sharp tool such as a knife or an awl through the inlet of the container 10. It is made of the step of cutting the portion (30).

Therefore, the inside of the container 10 and the see-through window 20 can penetrate each other so that the amount of contents filled in the container 10 can be assured with the see-through window 20 and can also be weighed.

The above-described mold A includes all forms for forming the container 10 as illustrated in FIG. 3, and the shape of the viewing window 2 is also a hollow portion 22 sealed by the recess 23. As long as it can form any shape can be molded in the container (10).

Above the mold A is a known extruder C, from which a cylindrical tube of plastic material or parason D is extruded. One side of the mold apparatus is a blower including a pipe (B). Extruders and ducts are not shown in detail because their structure belongs to a type known in conventional blow molding equipment.

The effect of the present invention produced by the above step is one time compared to the conventional method that has to go through several steps, such as a preliminary step for forming the see-through window to form a see-through window and the process of combining the see-through window to the container after the container is manufactured. Since the see-through window is molded in the container during the blow molding process, the productivity can be maximized by reducing the amount of work. In addition, the method of joining the see-through window to the container already produced by the blow molding process is between the see-through window and the joint or fusion part of the container. In the present invention, since the see-through window is heat-sealed during the blow molding process of the container, there is no gap between the container and the see-through window, and thus the contents do not leak.

Claims (1)

Fixing a see-through window 20 having projections 21 and recesses 23 on the inner wall of the mold A while the mold A is in an open position, in the method of forming a container having a transparent see-through window; The step of extruding the parison (D) between the open mold (A), the step of closing the open mold (A), and blows air into the mold by blowing (B) to form the container 10 And a step of fusing the Parison D with the outer circumferential surface of the recess 23 while surrounding the recess 23 of the viewing window 20, and after the container 10 is molded, the mold A is opened. And a step of cutting the inflation portion (30) of the container detached from the mold.