KR20020004521A - Apparatuses for Preparing Plastic Bottle - Google Patents

Abstract

PURPOSE: A plastic container forming device is provided to reduce the percent defective and to restrain the wear of the connecting portion of a second piston and an upper mold by uniformly distributing the force applied to the upper mold. CONSTITUTION: A plastic container forming device comprises: a lower mold(20) to form a body of a container filled with a content; a first clamp(30) connected to a first piston(60); an upper mold(21) to form the upper portion of the container; a second clamp(31) connected to a second piston(61); and a support unit including a first cylinder(50) to reciprocate the first piston and a second cylinder(51) to reciprocate the second piston. The force applied from the second piston is uniformly transmitted to the entire portion of the upper mold via the second clamp. Therefore, percent defective is reduced in the sealing process.

Description

Plastic Container Molding Machine {Apparatuses for Preparing Plastic Bottle}

The present invention relates to a molding apparatus for a plastic container filled with the contents.

In the manufacturing method of the plastic container filled with the contents, the extruder extrudes the plastic resin in the form of a parison, inserts it into the mold, and then closes the lower mold to seal the lower end, and then blows the blow pin installed at the top. The container body is formed by injecting air into the parison and / or drawing the air present in the space between the parison and the mold into the outside of the mold through a vacuum pin drilled in the mold. Then, the contents are injected into the body of the molded container and the upper part is sealed to complete the contents filled plastic container.

Therefore, the upper mold (sealing mold) is located on the upper upper mold lower than the lower mold for forming the container body. Therefore, in order to manufacture a plastic container capable of filling the contents and a plastic container filled with the contents as described above, the lower mold for forming the body of the container by blow molding or vacuum molding and for forming or sealing the upper portion of the container The upper mold is needed.

In addition, in order to manufacture the plastic container, the upper mold working process proceeds after the lower mold working process is completed, and the upper mold and the lower mold must be completely in contact with each other for the complete molding of the container. Friction occurs. For a more detailed description of this process, a conventional molding apparatus for producing a plastic container filled with the contents will be described with reference to FIG.

1 is a schematic diagram of an apparatus 10 for molding a plastic container filled with contents, in which a clamp 30 equipped with a lower mold 20 for forming a main body of the container extends into the support 40. The first piston 60 reciprocating into the first cylinder 50 is operated in the horizontal direction (as viewed in front view) according to the order of the working process. On the other hand, the upper mold 21 for forming the upper portion of the container is mounted on the upper portion of the clamp 30 and the second piston 61 reciprocating into the second cylinder 51 extending into the drive unit 70. By the operation of the work process in the left and right directions. At this time, the lower end of the upper die 21 is in sliding motion with the upper end of the lower die 20, the clamp 30 is mounted on the lower die 20 and the second cylinder 51 of the upper die 21 at the same time. Is fitted.

More specific configuration of the device associated with the operation of the upper mold of such a forming device

2 and 3 are as follows. The second cylinder 51 penetrates the clamp 30, and the second piston 61 reciprocates into the second cylinder 51 by a hydraulic device (not shown) inside the driving unit 70. Done. In the fastening method of the second piston 61 and the upper mold 21, the male screw 80 of the second piston 51 is coupled to the female screw 81 of the upper mold 21 and is connected to the coupling member 90. It is a way of tightening again.

Since the lower mold 20 is operated by the first thicker and shorter piston 60 in a state where it is mounted by the clamp 30, it is very stable and almost no operation deviation occurs when the mold is closed. On the other hand, since the upper mold 21 moves in contact with the upper end of the lower mold 20, abrasion occurs due to friction, and all the devices related to the upper mold 21 are clamped to which the lower mold 20 is mounted. Since it is mounted on the upper portion of 30, in order to withstand the resulting load, the size of the second piston 61 or the like, which is the device associated with the upper mold 21, must be reduced. Thus, as shown in FIG. 3, the size of the second piston 61 is relatively smaller than the first piston 60, and two or more second pistons (for the even distribution of the force applied to the mold). 61) is mounted on the mold.

However, the sealing process is a process in which the two second molds 21 are strongly engaged with each other, and the molds reciprocate from side to side several thousand to tens of thousands times a day, and the speed of the reciprocating motion is higher than that of the first mold 20. Since it is relatively fast, a lot of force is transmitted to the coupling portion of the second piston 61 and the second mold 21 and fatigue accumulates, so that the screw thread of the coupling portion is easily broken. In addition, in order to improve the efficiency of production, a plurality of container shapes are stamped so that a plurality of plastic containers can be molded at the same time, the length of the mold becomes very long in width. Therefore, at least two or more pistons are being used together, and it is necessary to simultaneously transmit a completely uniform force to such a plurality of pistons throughout the mold. Otherwise, the simultaneous forces are not evenly distributed, resulting in rapid deformation and damage of the mold, such as warping of the mold, high defects in the manufactured product, such as poor sealing of the plastic container, leakage, and the like. Since the breakage phenomenon of the fastening part becomes larger, a problem arises in that the operating deviation should be periodically reviewed.

Accordingly, an object of the present invention is to solve these problems of the prior art at once and to solve the technical problems that have been requested from the past.

That is, by mounting the second piston together to the support on which the first piston is mounted, thereby increasing the size of the second piston, uniform distribution of the force applied to the entire upper mold to achieve the above effects. The purpose.

In addition, by inducing the sliding motion of the upper mold and the lower mold in a constant direction to uniformly distribute the force applied to the upper mold, to reduce the defect of the product and to reduce the wear of the fastening portion of the upper mold and the second piston to operate it. The purpose is to reduce the life of the device.

1 is a schematic vertical cross-sectional view of a conventional molding apparatus for molding a content filled plastic container;

2 is an enlarged partial vertical cross-sectional view of the upper portion of the molding apparatus of FIG. 1;

3 is a horizontal sectional view of A-A of the forming apparatus of FIG. 2;

4 is a schematic vertical cross-sectional view of a molding apparatus which is one embodiment of the present invention;

5 is an enlarged partial vertical cross-sectional view of the upper portion of the forming apparatus of FIG. 4;

6 is a horizontal cross-sectional view of B-B of the molding apparatus of FIG. 5;

7 is a vertical sectional view of the contact surface of the upper mold and the lower mold of the molding apparatus of one embodiment of the present invention;

8 is a vertical cross-sectional view of the contact surface of the upper mold and the lower mold of the molding apparatus according to another embodiment of the present invention.

Description of the symbols of the main parts of the drawings

10: forming apparatus 20: lower mold

21: upper mold 22: guide protrusion

23: guide groove 24: bearing

25: separation prevention extension portion 30: clamp (first clamp)

31: second clamp 40: support

50: first cylinder 51: second cylinder

60: first piston 61: second piston

70: drive unit 80: male thread

81: female thread 90: coupling member

In order to achieve the above object, the present invention is a molding apparatus for manufacturing a plastic container filled with the contents,

Lower mold for forming the body of the container,

A first clamp mounted on the lower mold and fastened to the first piston,

Upper mold for forming the top of the container,

A second clamp mounted on the upper mold and fastened to the second piston,

And a support cylinder for supporting the device, each having a first cylinder capable of reciprocating the first piston and a second cylinder capable of reciprocating the second piston.

Hydraulic devices for driving the first cylinder and the second cylinder, etc. are built in the support, and the first piston and the second piston are fastened to separate clamps (the first clamp and the second clamp), respectively. The size can be increased. Therefore, only one second piston is sufficient, since the mold is fixed to the clamp so that the hydraulic force is transmitted by the area of the clamp. Like the first piston, stable operation is possible.

4 to 6 will be described in more detail the contents of the present invention.

The upper mold 21 is operated in contact with the lower mold 20 and is mounted to the second clamp 31 separately from the first clamp 30 on which the lower mold 20 is mounted. The second clamp 31 is reciprocated by the second piston 61, and the second cylinder 51 which induces the reciprocation of the second piston 61 performs the reciprocation of the first piston 60. It is embedded in the support 14 together with the first cylinder 50 to guide. In particular, as shown in FIG. 6, since the upper mold 21 is mounted on the second clamp 31, the force applied from the second piston 61 is applied to the upper mold 21 through the second clamp 31. When the sealing process of the upper part of the plastic container is very evenly delivered, the defect rate of the product is very small, and when the tensile force is applied to the second piston 61 to open the mold, the second clamp 31 is provided with a plurality of fastening members 90. Since the tensile force is applied to the entire upper mold 21 through, the possibility of breakage of the fastening portion is much less.

Looking at the process of manufacturing a plastic container filled with the contents using such a molding apparatus, the upper mold 21 and the lower mold (2) is formed by extrusion of the parison extruded through an extruder (not shown) located above the molding apparatus. 20), the lower mold 20 is closed by the action of the first piston 60 to seal the lower end of the parison. Blowing pins (not shown) located at the top of the device is lowered to inject air into the parison, the parison is expanded to form the container body in the shape stamped on the inner surface of the lower mold (20). In another method, the container body is formed as described above by extracting air existing between the parison and the mold through the vacuum pin drilled in the lower mold 20 to the outside of the mold. Then, after the injection tube (not shown) is lowered to inject the contents into the container body, the upper mold 21 is closed by the action of the second piston 61 to seal the upper part of the container. When the sealing process is completed, the lower mold 20 and the upper mold 21 are opened by the action of the first piston 60 and the second piston 61 and the plastic container filled with the contents is taken out.

The present invention relates to a lower mold for forming a main body of a container and a plastic molding device for molding or sealing an upper part of a container, the contents including a configuration capable of accurately inducing a reciprocating motion of the upper mold to reduce an operation error in a manufacturing process. Filling plastic container forming apparatus is also described.

Specifically, it includes a structure in which one or two or more reciprocating induction furnaces are attached to a contact portion between the upper mold and the lower mold. For example, an induction protrusion extending in the reciprocating direction of the mold is formed at the upper end of the lower mold in contact with the upper mold, and a corresponding induction groove is formed at the lower end of the upper mold. In some cases, the guide groove may be formed at the upper end of the lower mold, and the guide protrusion may be formed at the lower end of the upper mold.

The guide protrusion and the corresponding guide groove may have various shapes. That is, the cross-sectional shape of the guide protrusion is not particularly limited, such as triangular, trapezoidal, square, rail, etc. Among them, the cross-sectional shape of the trapezoidal guide protrusion is shown in FIG. 7, and the cross-sectional shape of the rail guide protrusion is shown in FIG. 8, respectively. It is. The guideway illustrated in FIG. 7 is provided with two trapezoidal induction protrusions 22 at the upper end of the lower die 20, and corresponds to the trapezoidal induction protrusion 22 at the lower end of the upper die 21. A trapezoidal guide groove 23 is provided. 8, two rail-type guide protrusions 22 are installed at the upper end of the lower mold 20, and the rail-type guide protrusion 22 is disposed at the lower end of the upper mold 21. The rail guide groove 23 corresponding to this is provided.

In some cases, in order to more reliably prevent departure and induction of the mold during the reciprocating motion, it may be deformed into a structure surrounding the sides of the upper mold by extending both ends of the lower mold. That is, FIG. 7 illustrates an embodiment structure of the present invention in which the separation preventing extension portions 25 at both end portions of the lower mold 20 completely surround both sides of the upper mold 21.

Preferably, a separate configuration may be added to the contact surface of the lower mold and the upper mold to reduce the frictional force.

Such a separate configuration may include a bearing provided between the lower mold and the upper mold, or a resin having a small coefficient of friction coated on the upper surface of the lower mold and the lower surface of the upper mold. The bearing may be a stainless steel ball or a high strength / hard plastic ball. Since the mold is generally made of stainless steel, stainless balls are particularly preferable for bearings. The bearing is installed between the upper mold and the lower mold, but in some cases, the upper mold and / or the lower mold may have separate grooves for the movement of the bearing. As the coating resin, a fluorine resin, an olefin resin, a silicone resin, or the like may be used, and ultra high molecular weight polyethylene (UHMWPE: Ultra High Molecular Weight Polyethylene) having a low friction coefficient as well as a large wear resistance is particularly preferable. In FIG. 7, the bearing 24 is positioned between two guide protrusions 23 placed on the upper end of the lower mold 20, and the upper mold 21 is reciprocated by the guide groove 23 to guide the bearing. (24) has a structure in which the frictional force with the lower die 20 is minimized.

The configuration of the induction furnace of the upper mold and the lower mold may be applied independently to the conventional molding apparatus and used separately from the configuration of the molding apparatus, which is another aspect of the present invention. That is, the present invention can be applied to the conventional molding apparatus of FIGS. 1 to 3, in which case a problem occurring in the conventional molding apparatus, for example, a failure of a molded product and a piston caused by not applying uniform force to two pistons Damage to the upper mold fastening portion can be further prevented.

Further preferred contents filling plastic molding apparatus includes a lower mold for forming the main body of the container, a first clamp for mounting the lower mold and fastened to the first piston, an upper mold for forming the upper part of the container, and an upper mold. A second clamp clamped to the second piston, a first cylinder capable of reciprocating the first piston and a second cylinder capable of reciprocating the second piston, respectively; And one or more reciprocating induction furnaces are attached to a contact portion of the upper mold and the lower mold.

The content-filled plastic container molding apparatus of the present invention can be used for the production of a plastic container capable of filling the contents as well as a plastic container filled with the contents.

In the molding apparatus of the present invention, in order to further increase the efficiency of the process, it is possible to install other additional apparatuses or to change some of the configuration of the apparatus within the scope of the present invention.

Those skilled in the art to which the present invention pertains may have various applications within the scope of the present invention based on the above description.

The content-filled plastic container forming apparatus of the present invention is guided by a cylinder embedded in the support of the operating piston of the upper mold for forming the upper portion of the container, so that the work process can be performed with only one large piston as in the lower mold. Therefore, it is not necessary to frequently check whether the force applied to the front face of the mold is evenly applied, and it is very unlikely that the joint between the mold and the piston is broken. In addition, when the reciprocating induction path is installed on the friction surface of the upper mold and the lower mold, it is possible to accurately guide the upper mold, and accordingly, the possibility of breakage of the fastening portion between the mold and the piston is further lowered, thereby increasing the service life of the device. have.

Claims (6)

A lower mold for forming the body of the container; A first clamp mounted to the lower mold and fastened to the first piston; An upper mold for forming an upper portion of the container; A second clamp for mounting the upper mold and fastened to the second piston; A first cylinder in which the first piston can reciprocate and a second cylinder in which the second piston can reciprocate, respectively, and include a support for supporting the device. Molding device. A molding apparatus for forming or sealing a lower mold for forming a main body of a container and an upper end of the container, the content filling comprising a structure in which one or more reciprocating guideways are attached to a contact portion of the upper mold and the lower mold. Forming apparatus of plastic container. 3. The reciprocating induction path according to claim 2, wherein the reciprocating induction path forms an induction protrusion extending in the reciprocating direction of the mold at the upper end (lower end) of the lower mold (upper mold) and corresponds to the lower end (upper end) of the upper mold (lower mold). Molding apparatus for a contents-filled plastic container, characterized in that the structure to form a guide groove. 4. The molding apparatus according to claim 2 or 3, wherein both ends of the lower mold are extended to surround side surfaces of the upper mold. 4. The contents-filled plastic container according to claim 2 or 3, wherein a bearing is installed between the lower mold and the upper mold, or a resin having a small coefficient of friction is coated on the upper surface of the lower mold and the lower surface of the upper mold. Molding device. A lower mold for forming the main body of the container, a first clamp for mounting the lower mold and fastened to the first piston, an upper mold for forming the upper part of the container, a second for mounting the upper mold and fastened to the second piston A clamp, a first cylinder capable of reciprocating the first piston and a second cylinder capable of reciprocating the second piston, respectively, and including a support for supporting the device, wherein the upper mold and the lower mold Apparatus for molding a content-filled plastic container in which one or more reciprocating induction furnaces are provided at a contact site.