JPH02196621A - Production of stretched hollow vessel fitted with handle - Google Patents

Abstract

PURPOSE:To sufficiently wind the wall surface of a vessel around the engaging parts of a handle and to enhance the fitting strength of the handle by utilizing a preformed article wherein the parts correspondent to the handle fitting part of the vessel main body after molding have been formed on the thick-walled parts and performing blow- molding to integrate both the vessel main body and the handle. CONSTITUTION:In a preformed article 2, the thick-walled parts 6, 6 are formed on the drum part correspondent to the handle fitting parts 5, 5 of a vessel main body 4 after molding. For example, this preformed article 2 is obtained by injection-molding polyesters such as polyethylene terephthalate. The ratio (t1/t2) of wall thickness t1 of the thick-walled part 6 of the preformed article 2 to the wall thickness t2 of the other drum part is properly regulated to 1.03-1.15. Both the preformed article 2 and the handle part 3 formed by such a way are held to the prescribed position of the inside of a blow-molding die 10. The preformed article 2 is expanded by introducing pressure fluid thereinto through a holder 11 and a stretched hollow vessel 1 fitted with the handle is molded which has a shape correspondent to the blowmolding die 10. At this time, the thick-walled parts 6, 6 of the expanded preformed article 2 are wound around the engaging parts 7, 7 of both ends of the handle 3 and thereby both the handle 3 and the vessel main body 4 are integrated.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for manufacturing a stretched hollow container with a handle, and more specifically, a handle formed separately from the container body is attached to the container during blow molding of the container body. The present invention relates to a method of manufacturing a stretched hollow container with a handle by integrating it with a main body.

[Conventional technology]

Conventionally, when molding stretched hollow containers such as plastic bottles and stick bottles, plastic bottles with handles are made using resins such as polyester resins such as polyethylene terephthalate, which are difficult to simultaneously blow mold the container body and handle. The method for manufacturing the container body is to separately mold a preform that will become the container body and a handle body, place them at predetermined positions in a blow mold, and blow pressurized fluid into the preform to form the container body. A method has been proposed in which the container body and handle are integrated by blow molding (see Japanese Patent Laid-Open No. 58-99350).

[Problem to be solved by the invention]

However, in the above-mentioned manufacturing method, the area near the handle attachment part of the container body is stretched into a complicated shape, making it thinner than other parts, and it is difficult to wrap the container wall surface sufficiently around the handle attachment area. Because of the difficulty, the strength was unstable, and the appearance was particularly weak.

Therefore, it is an object of the present invention to provide a method for manufacturing a stretched hollow container with a handle, which can improve the appearance of the handle attachment part of this type of stretched hollow container with a handle, and also improve the strength of the handle attachment part. The purpose is

[Means to solve the problem]

In order to achieve the above object, the present invention arranges a handle body and a preformed container body in a blow mold, blow molds the preformed product, and integrates the handle body and the container body. In manufacturing a stretched hollow container with a handle, the preformed product is a preformed product in which a portion of the container body after molding corresponding to the handle attachment portion is a thick wall portion. A method of manufacturing a stretched hollow container is provided.

[For production]

As mentioned above, by making the part of the preform that corresponds to the handle attachment part thick, it will not become thin even when stretched into a complicated shape during blow molding, and the handle attachment part will not become thin. It can be wrapped around enough.

[Example] Hereinafter, the present invention will be described in further detail based on an example shown in the drawings.

FIG. 1 is a front view showing a preformed product used in the present invention and a hollow container with a handle made by blow molding the preformed product, and FIGS. 2 and 3 are for explaining the state of blow molding. The figure is a front view showing the state inside the blow mold, and FIG. 3 is a cross-sectional view taken along the line ■-■ in FIG. 2. In addition, Figures 4 and 5 show other embodiments of the preform. Figure 4 is a partially cutaway front view of the preform, and Figure 5 is a sectional view taken along the line V-■ in Figure 4. be.

First, in FIGS. 1 to 3, a stretched hollow container 1 with a handle is shown.
is manufactured by integrating a preform (preform, parison) 2 previously formed into a bottomed tube shape and a handle body 3 formed into a predetermined shape.

The preformed product 2 includes a handle attachment portion 5 of the container body 4 after molding,
A thick wall portion 6.6 is formed on a body portion corresponding to 5, and can be obtained by a general method such as injection molding of a synthetic resin such as polyester such as polyethylene terephthalate.

The thickness of the thick portion 6 of this preform 2 is 1. The ratio (t + / t 2 ) of the wall thickness t2 and the wall thickness t2 of the other body portion can be set as appropriate depending on the shape of the container body 4 to be molded, the shape of the engaging portions 7°7 at both ends of the handle body 3, etc. Although it is possible, 1.03 to 1.15 is generally appropriate.

If this ratio greatly exceeds 1.15, for example, the thick part 6
If the wall thickness of the container body 4 is set to the optimum size, the wall thickness of the body of the container body 4 becomes relatively thin, which may cause a problem in the buckling strength of the container after molding.

On the other hand, if the wall thickness of the body is set to the optimum size, the thick wall portion 6
becomes too thick, which not only results in wasted material, but also reduces the strength of the handle attachment portion 5 due to a decrease in the stretching ratio.

In addition, if the ratio of the above wall thickness is less than 1.03, the thickness of the thick wall portion 6 and the wall thickness of the body will be approximately the same, and if the wall thickness of the body is set to the optimum size, the handle If the wall thickness of the mounting portion 5 is not sufficient and it is difficult to achieve the object of the present invention, and on the other hand, if the thick wall portion 6 is made to have the optimum wall thickness, the entire body portion is formed to be thick. This may lead to waste of material and a decrease in strength due to a decrease in the stretching ratio.

Similarly, the axial width W of the thick portion 6 can be set as appropriate depending on the shape of the container body 4, etc.
It can be formed into an optimal size depending on the shape of the mold and taking into consideration errors during blow molding.

On the other hand, the handle body 3 can be made of an appropriate material, for example, one made by injection molding of synthetic resin such as polypropylene or polyethylene, or one made of other metal or wood processed into a predetermined shape. An engaging portion 7.7 consisting of a convex portion or a concave portion that engages with the main body 4 is formed.

The thus formed preform 2 and handle body 3 are first held at a predetermined position within the blow mold 10. That is, the preform 2 is held with its mouth 2a held by the holder 11, and the handle body 3 is held in the holding recess 12 formed in the wall of the blow mold 10. It is placed in a blow mold 10, and both molds 10a, 10b are closed. In this state, pressure fluid is introduced into the preform 2 from the holder 11 to expand the preform 2 and form the stretched hollow container 1 with a handle in a shape corresponding to the blow mold 10. At this time, the thick part 6.6 of the expanding preform 2 wraps around the engaging parts 7.7 at both ends of the handle body 3, and the handle body 3
and the container body 4 are integrated, and the stretched hollow container 1 with a handle shown in FIG. 1 can be obtained.

The handle attachment portion 5.5 of the stretched hollow container 1 with a handle is formed by stretching the thick wall portion 6.6 of the preform 2. Therefore, the wall thickness of the handle attachment portion 5.5 is It does not become thin and can be stretched sufficiently to wrap around the engaging portions 717 at both ends of the handle body 3.

This improves the appearance of the handle attachment portion 5 of the container body 4, and also improves the strength of the attachment of the handle. Furthermore, since the strength of the attachment of the handle is improved, it is possible to omit supplementary bonding of the container body 4 and the handle body 3 by hot melt bonding or the like.

In the above embodiment, two thick-walled parts 6 of the preform 2 are newly formed around the body of the preform 2, but as shown in FIG. 4 and FIG. It is also possible to form two convex portions 8° 8 in the portions corresponding to the handle attachment portions 5, 5 and make these portions thick. In addition, the build-up for forming the thick part is not limited to the outer circumferential side of the preform 2, but can be formed on the inner circumferential side or in both directions to an appropriate thickness.
Furthermore, it is also possible to form one continuous convex portion corresponding to the engaging portions 7, 7 at both ends of the handle body 3.

Experimental Example Preforms with different ratios of the thickness t1 of the thick wall part and the thickness t2 of the other body parts were prepared, and a plastic bottle with a capacity of 1.8 mm was molded, and the handle was attached with strength. compared. The material of the preform was polyethylene terephthalate, and the material of the handle was polypropylene, each of which was molded into a predetermined shape by general injection molding. The conditions for blow molding were also the same as those conventionally used for blow molding containers of this type. To measure the strength of the handle installation, fill the molded container with 1.8 J of water, seal it tightly, and measure the height at which the handle will not come off when dropped vertically onto a concrete floor in an upright position. did. The height at which the handle does not come off is defined as the height at which the handle does not come off at all or only 1 out of 10 containers come off when 10 similarly molded containers are dropped.

Show the results at the memorial service.

〔Effect of the invention〕

As explained above, the present invention performs blow molding using a preformed product in which the portion corresponding to the handle attachment portion of the molded container body is thickened inside, thereby integrating the container body and the handle body. , the wall of the container can be sufficiently wrapped around the engaging part of the handle, and the wall thickness will not become thin.
Attaching the handle can improve strength and
A stretched hollow container with a handle that is also excellent in appearance can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a preformed product used in the present invention and a hollow container with a handle made by blow molding the preformed product. FIGS. 2 and 3 are for explaining the state of blow molding. 3 is a front view showing the state inside the blow molding mold, FIG. 3 is a sectional view taken along the line ■-■ in FIG. 2, and FIGS. 4 and 5 show other embodiments of the preform. 5 is a partially cutaway front view of the preform, and FIG. 5 is a cross-sectional view taken along line V-■ in FIG. 4. 1... Stretched hollow container with handle 2... Preformed product 3
...Handle body 4...Container body 5...Handle attachment part 6...Thick wall part 7...Engagement part 8...Convex part 1°...Blow molding mold 11... Holder
12... Holding recess force 2 yen 4th day

Claims (1)

[Claims] 1. Place a handle body and a preformed container body in a blow molding mold, blow mold the preformed product, and integrate the handle body and the container body to produce a stretched hollow container with a handle. A method for manufacturing a stretched hollow container with a handle, characterized in that the preformed product is a preformed product in which a portion corresponding to the handle attachment portion of the container body after molding is a thick walled portion.