JP2000202894A - Hollow blow molded container with longitudinal ribs and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a deformation resistant strength of a hollow blow molded container by integrally molding a plurality of ribs in an axial direction of the container. SOLUTION: A plurality of ribs 2 are integrally molded at a predetermined interval in an axial direction on an inner periphery of the hollow blow molded container 1 so as to finish near a bottom 7 through a peripheral wall 6 from a shoulder 5 under a bottle neck portion 4 formed with a threaded part 3. The ribs 2 are formed axially on the inner periphery of the container 1, and the ribs 2 are thicker than general thicknesses of the wall 6 and the bottom 7 and projected inward. The plurality of the ribs are formed in the axial direction of the container thereby to improve a deformation resistant strength of the container, to lose a weak feel of touch when grasped, and to facilitate its handling. Further, the container can easily maintain self-supporting properties, and the containers can be stacked by improving its buckling strength.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow blow-molded container having vertical ribs and a method for producing the same, and more particularly to a structure for improving the deformation resistance of a thin plastic container and a method for producing the same.

[0002]

2. Description of the Related Art A thin-walled plastic container for storing a liquid for sale or the like is generally a hollow container having a bottle-shaped cross section and having a circular or square polygonal cross section. Is provided with a screw portion, and a cap screwed to the screw portion is opened and closed to allow the content liquid to be taken in and out.

[0003] This thin plastic container is filled with a preform or parison in a mold by a biaxial stretch blow molding method or a direct blow molding method, and is blown into the preform or parison by blowing air. It is well known that this is a hollow blow-molded container formed by being fixed to the inner surface of a mold and solidified by cooling.

At present, the thickness of this container is reduced as much as possible in order to save resources and reduce costs. Since the shape of the container must be maintained with respect to the liquid content even if the thickness is reduced, the container has an annular shape on the peripheral wall. Forming corrugated unevenness, or forming alternately concave and convex portions in the peripheral wall portion in the container axial direction, or
The shape of the container can be maintained by changing the diameter of the peripheral wall in a stepwise manner.

[0005]

However, thin-walled hollow blow-molded containers have low deformation resistance and generally have high elasticity and resilience, but have a light weight and soft feel to the touch. Therefore, there is a surface that is difficult to handle when grasped with a hand or a robot hand, and because the buckling strength is low when standing alone, it can not be stacked, and the liquid content easily spills when refilling the liquid There are such properties. Furthermore, a container made of a soft film-shaped material is soft even if it can stand on its own, and it is generally difficult to fill the contents liquid because it must be securely held.

Accordingly, an object of the present invention is to improve the deformation resistance of a hollow blow-molded container.

[0007]

According to a first aspect of the present invention, there is provided a hollow blow-molded container with vertical ribs, wherein a plurality of ribs are integrally formed in the axial direction of the hollow blow-molded container. .

According to a fourth aspect of the present invention, a plurality of concave ridges are formed in the hollow blow-molded container in the axial direction, and ribs are fitted into the concave ridges to form ribs. I do.

According to a second aspect of the present invention, there is provided a method for manufacturing a hollow blow-molded container with vertical ribs, the method comprising: The parison with ribs formed above is discharged, and the parison with ribs is clamped in a mold and blow-molded to form a plurality of ribs in the axial direction of the container.

According to the fifth aspect of the present invention, after the rib member is suction-fixed to the inner surface of the mold for forming the hollow blow-molded container, the preform or parison is inserted, the mold is clamped, and blow molding is performed. A plurality of ribs are integrally formed in the axial direction.

[0011] Therefore, since a plurality of ribs are formed at predetermined intervals in the axial direction in spite of being a thin and lightweight plastic container, the overall deformation resistance of the container is improved and a soft touch is lost. It is self-supporting, easy to handle, and improves buckling strength.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 to 3, a plurality of ribs 2 are formed at predetermined intervals in the axial direction on the inner peripheral surface of the hollow blow-molded container 1 from the shoulder 5 below the bottle mouth 4 on which the screw 3 is formed. It is integrally formed so as to end near the bottom portion 7 through the peripheral wall portion 6. As shown in FIG. 3, the ribs 2 are formed on the inner peripheral surface of the hollow blow-molded container 1 in the axial direction, and these ribs 2 are larger than the general thickness of the shoulder portion 5, the peripheral wall portion 6, and the bottom portion 7. Is also thick and protrudes inward.

The method for manufacturing the hollow blow-molded container 1 will be described. As shown in FIG.
The rib forming grooves 22 are formed at predetermined intervals on the inner peripheral surface of the die 21 at 0, or the rib forming grooves 25 are formed at predetermined intervals on the outer peripheral surface of the core 23 as shown in FIG. 5 and 6, a ridge 27 is formed in the outer peripheral surface of the parison 26 in the axial direction as shown in FIGS. 5 and 6, or the inner periphery of the parison 26 is formed as shown in FIGS. A ridge 28 is formed on the surface in the axial direction.
4 to 9 show an example in which four ridges 27 and 28 are formed in the circumferential direction, and are not intended to be limited to four.

When such a parison 26 is inserted into a mold of a molding machine by the hollow blow molding method and the mold is blow-molded, the ridges 27 and 28 become thicker than other portions and project inward. It is molded as a rib 2. That is, a parison 26 having a ridge 27 or a ridge 28
The ribs 2 are formed on the inner peripheral surface side of the plastic container 1 as shown in FIG.

Next, another embodiment of the present invention will be described with reference to FIGS. As shown in FIGS. 10 to 12, the hollow blow-molded container 1 a has a plurality of ribs 2 a formed integrally with the inner peripheral surface of the peripheral wall portion 6 in the axial direction.
As shown in FIG. 12, a plurality of ribs 2a are provided at predetermined intervals in the circumferential direction of the peripheral wall portion 6, and as shown in FIG. The fitted concave streak portion 9 is formed, and both are closely contacted and integrated.
The rib member 8 may be the same as or different from the peripheral wall portion 6.

A method of manufacturing the hollow blow-molded container 1a will be described. As shown in FIG. 13, the rib member 8 is attached to the cavity inner surface 11 of the half molds 10, 10 by the hand 13 of the rib mounting device 12. After being gripped (A), (E) and adsorbed and fixed to the cavity inner surface 11 (B), (F),
The preform or parison 14 is inserted into the molds 10 and 10 and clamped, and air is blown into the parison 14 (C).
(G), the cavity inner surface 1 of the mold 10
A hollow blow-molded container 1a as a product cooled and solidified along 1 is obtained (D) and (H). Therefore, the rib member 8
Are integrated in a state where they are fitted into the concave ridges 9 formed by surrounding the wall 6 and the like of the hollow blow-molded container 1a, and are not easily peeled off. Further, as shown by phantom lines in FIG. 11, the concave groove 9 into which the rib member 8 is fitted.
May be formed from the shoulder 5 to the bottom 7. It should be noted that the present invention is not limited to the rib 2 pattern shown in FIG.

Since the ribs 2 and 2a are integrally formed at predetermined intervals in the axial direction of the hollow blow-molded containers 1 and 1a, the axial blow-resistant strength of the hollow blow-molded containers 1 and 1a is improved. Improve buckling strength. Therefore, it becomes possible to stack the hollow blow-molded containers 1 and 1a. Further, the deformation resistance of the hollow blow-molded containers 1 and 1a is improved as a whole, and the soft touch can be lost.

[0018]

According to the present invention described above, the deformation resistance of the container is improved by forming a plurality of ribs in the axial direction of the hollow blow-molded container, and the soft feel when the container is grasped is lost. In addition, handling becomes easy, and self-sustainability is easily maintained, buckling strength is improved, and stacking is possible.

[Brief description of the drawings]

FIG. 1 is a perspective view of a hollow blow-molded container showing an embodiment of the present invention.

FIG. 2 is a sectional view of a hollow blow-molded container showing an embodiment of the present invention.

FIG. 3 is a sectional view taken along line aa in FIG. 2;

4A is a cross-sectional view showing a discharge port of a parison extruder head, and FIG.

5 is a cross-sectional view showing a state in which the parison is discharged from the parison extruder head shown in FIG.

FIG. 6 is a sectional view taken along line bb in FIG. 5;

FIG. 7 is a sectional view (A) showing another discharge port of a parison extruder head and a bottom view (B) of a main part thereof.

8 is a cross-sectional view showing a state in which the parison is discharged from the parison extruder head shown in FIG.

FIG. 9 is a sectional view taken along the line cc in FIG. 8;

FIG. 10 is a perspective view of a hollow blow-molded container showing another embodiment of the present invention.

11 is a sectional view of the hollow blow-molded container shown in FIG.

FIG. 12 is a sectional view taken along line dd in FIG. 11;

13 is an explanatory view of a molding process of the hollow blow molded container of FIG. 10, wherein (A) to (D) are cross-sectional views, and (E) to (H) are main parts corresponding to (A) to (D). FIG.

[Explanation of symbols]

 1, 1a ... hollow blow-molded container 2, 2a ... rib 8 ... rib member 9 ... concave ridge 10 ... mold 11 ... cavity inner surface 12 ... rib mounting device 13 ... hand 14 ... parison 20 ... parison extruder head 21 ... die 22, 25 ... rib forming groove 23 ... core 26 ... parison 27, 28 ... ridge

Claims (6)

[Claims] 1. A hollow blow-molded container with vertical ribs, wherein a plurality of ribs are integrally formed in the axial direction of the hollow blow-molded container. 2. In a hollow molding method for obtaining a hollow container by blowing air into a parison, a parison with ribs formed by forming a plurality of ribs in an axial direction is discharged to the parison, and the parison with ribs is clamped by a mold. A method for producing a hollow blow-molded container with longitudinal ribs, comprising forming a plurality of ribs in the container axial direction by blow molding. 3. The parison extruder head according to claim 2, wherein said parison is obtained by a parison extruder head having a plurality of rib forming grooves formed on an inner peripheral surface of a die or an outer peripheral surface of a core. A method for producing a hollow blow molded container with ribs. 4. A hollow blow molding with vertical ribs, wherein a plurality of concave ridges are formed in the hollow blow molding container in the axial direction, and ribs are fitted into the concave ridges to form ribs. container. 5. A method in which a rib member is suction-fixed to the inner surface of a mold for forming a hollow blow-molded container, and then a preform or a parison is inserted, and the mold is clamped and blow-molded to form a plurality of pieces in the axial direction of the molded container. A method for producing a hollow blow-molded container with vertical ribs, wherein the ribs are integrally molded. 6. The blow molding is biaxial stretch blow molding, or
6. A direct blow molding method.
A method for producing the hollow blow-molded container with vertical ribs according to the above.