JP2949459B2 - Hollow container made of polyethylene terephthalate resin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biaxially stretch blow-molded bottle made of a synthetic resin, particularly a polyethylene terephthalate resin, provided with a reduced pressure absorption function portion on a body portion.

[0002]

2. Description of the Related Art A biaxially stretch blow-molded polyethylene terephthalate (hereinafter referred to as "PET") resin bottle is relatively economical because of its excellent properties, a relatively large one can be molded thin. It is used in various fields as a liquid container because it has excellent physical properties, mechanical strength, and good appearance.

[0003] Such a PET resin bottle is excellent in mechanical strength in spite of its thinness. However, since the main body portion of the bottle is formed to be thin, it is generated in the bottle. Due to the decompression phenomenon, a part of the body portion is undesirably depressed and deformed, and there is an inconvenience that the appearance of the bottle as a product is significantly reduced.

[0004] In order to eliminate the disadvantage of deformation of the body of the PET resin bottle due to the depressurization phenomenon, for example, as disclosed in Japanese Utility Model Laid-Open No. 57-199511, the body of A plurality of deformed panel walls which are easily depressed and deformed are provided, and the negative pressure generated in the bottle is absorbed by the depressed deformation of the deformed panel wall in a uniform state, and thus the other part of the trunk Various types of bottles have been proposed which are configured to prevent the occurrence of an undesired collapse deformation and prevent the appearance of the body from being deteriorated.

[0005]

However, the deformed panel wall of the container in the prior art described above is designed so that collapsed deformation due to reduced pressure generated in the bottle easily occurs.
Since it is formed in a state where it is simply depressed slightly inward in advance, there is a problem that the reduced pressure amount that can be absorbed is insufficient for the degree of the depressed deformation of the deformed panel wall with respect to the generated decompression amount. there were.

The conventional deformed panel wall is formed by depressing and deforming a part of the body of the container, and
The buckling strength of the torso is provided by providing these deformed panel walls because they are juxtaposed at equal intervals in the circumferential direction of the torso so as not to cause partial decompression deformation in the torso. However, there was also a problem that the temperature decreased.

[0007] Since the above-mentioned deformed panel wall is provided in the body of the container in a vertically elongated depression shape, the deformed panel wall is provided depending on the viewing angle of the bottle which is deformed under reduced pressure. There is a problem that the torso part may look extremely thin compared to the other torso parts, which gives a poor appearance to the bottle.

Further, since a bottle in which a decompressed state is generated is almost completely filled with a heated liquid, the bottle is pressurized at the beginning when the liquid is heated and filled and sealed. In order to be in the inflated state, the deformed panel wall of the torso is required to have not only the original reduced pressure absorbing ability but also the ability to absorb the pressurized pressure. Since the shape is such that it is curved and depressed, it cannot take a large swelling deformation to absorb the pressing force when pressure is generated, so that not only sufficient pressure absorption cannot be achieved, but also pressure expansion If the force is large, there is a problem in that the deformation panel wall is only deformed elastically swelling and becomes a reversing and protruding deformation, resulting in a permanent deformation state.

Therefore, the present invention has been made to solve the above-mentioned problems in the prior art, and a large amount of deformation that collapses and expands without reducing the buckling strength of the body of the bottle. A technical object of the present invention is to obtain a deformed panel wall, and it is an object of the present invention to obtain a bottle having a large amount of internal pressure change absorption, a high buckling strength, and a good external appearance.

[0010]

According to the present invention, as a means for solving the above-mentioned technical problems, at least a lower half of a body portion of a bottle is provided with a plurality of vertically long, substantially flat oval or elliptical shapes. When the deformed panel walls are arranged side by side in a depressed manner at equal intervals along the circumferential direction, the outer wall extends along the inner side surfaces of both side edges of the deformed panel wall over substantially the entire length range of the deformed panel wall. A pair of vertically long ribs formed in a convex shape are provided, and both ends of the ribs are provided so as to be curved inward.

Further, in the bottle provided with the deformed panel wall formed as described above, the height of the lower half of the body including the bottom of the bottle is increased by the body including the shoulder and the mouth and neck. A bottle with a structure smaller than the height of the upper half is formed.

[0012]

The vertical ribs provided on the inner peripheral surfaces of both side edges of the vertically elongated, generally flat, oval or elliptical deformed panel wall provided on the body of the bottle-shaped container are provided on the deformed panel wall. Is formed by projecting a part of the rib outside and forming a convex shape, and by forming both ends of the rib strip so as to be curved inward along the peripheral edge of the deformed panel wall. When the wall is deformed, the rib is deformed in a direction in which the radius of curvature of the rib is increased, that is, is extended, and the width along the circumferential direction is increased.

With the above-described structure, when the pressure in the bottle changes in a sealed state, the changed pressure acts on the deformable panel wall, thereby extending and deforming the elongated rib. Due to the extension deformation of the rib, the deformed panel wall is displaced outward when the change in the pressure in the bottle is a change in pressure, and inward when the change in the pressure in the bottle is a change in pressure. Although it is displaced, a change in the internal volume of the bottle based on the displacement of the deformed panel wall absorbs a change in pressure that increases and decreases in the bottle.

In addition to the absorbing operation of the increasing and decreasing pressure change in the bottle due to the deformation of the elongated rib, similarly to the conventional one, the deformed panel wall itself projects according to the pressure change in the bottle. Needless to say, by bending or deforming so as to be depressed, the increased or decreased pressure change in the bottle is absorbed.

As described above, the entire length of the deformed panel wall is displaced so as to protrude or depress due to the elongation and deformation of the vertically elongated ribs in accordance with the change in the pressure in the bottle. The amount of change in the internal volume of the body can be large, thereby increasing the amount of pressure change absorbed in the bottle.

The elongated ribs are provided on the inner peripheral surfaces of both side edges of the deformed panel wall, and are provided in a projecting manner over substantially the entire height range of the deformed panel wall.
The column-shaped side walls (also referred to as lands) located between the respective deformed panel walls are located close to each other so as to sandwich both sides thereof, and the column-shaped side walls are structurally responsive to a vertical pressure load applied to the bottle wall. The buckling strength of the body wall portion provided with the deformed panel wall is thereby increased.

Further, the vertically elongated ribs protrude over substantially the entire length range of the deformed panel wall on the inner peripheral portions of both side edges of the deformed panel wall provided in a depressed state on the body of the bottle. Even if the depressurized and deformed bottle body is viewed from the lateral direction, the depressed shape surface of the deformed panel wall is not observed as an outline, and the protruding vertical rib strip surface is provided. Since it is observed as an outline, it does not look extremely thin.

[0018]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an optimal embodiment of the present invention. FIG. 1 is an overall front view showing a biaxially stretch-blown PET bottle 1 made of PET, the upper part of a cylindrical body 2 having a bottom. At the upper end of the torso wall portion, a short cylindrical mouth-and-neck portion 11 is provided upright and connected via a shoulder portion 10 in the shape of a truncated cone.

The body 2 has a center circumferential groove 8 provided substantially at the center of the body wall, and a body upper half 3 having four reinforcing rib circumferential grooves 9 arranged vertically, and six deformations. The panel wall 5 is divided into a body lower half 4 arranged side by side at equal intervals along the circumferential direction, and the height of the body lower half 4 including the bottom is equal to the body upper half 3 including the shoulder 10. The height of the deformed panel wall 5 formed on the lower half 4 of the body is generally smaller than the height of the conventional bottle of this type. As compared with the length in the height direction of the deformed panel wall, the ratio of the total height of the bottles of the same size is smaller.

Then, each deformed panel wall 5 of the bottle 1
Are formed in a vertically long elliptical shape, and vertically elongated ribs 6 provided on inner peripheral portions of both side edges of the deformed panel wall 5 are formed.
Are formed along the side edges of the deformed panel wall 5, and are formed in the shape of an elliptical arc in which the upper and lower ends of the rib strip 6 are curved inward, which is apparent from FIGS. As described above, the ribs 6 have a convex height slightly protruding outward from the continuous ridge line between the deformed panel wall 5 and the columnar side wall 7.

As shown in FIG. 3, the rib strips 6 sandwich one rib-shaped side wall 7 through a part of the peripheral wall of the deformed panel wall 5 adjacent to both sides. Since it is positioned in a posture, the buckling strength of the columnar side wall 7 having a simple vertically long plate-like structure is reinforced from both sides.

FIG. 4 illustrates the operation of absorbing the pressure change of the deformed panel wall 5 when a pressure change occurs in the bottle 1. It shows the corresponding displacement state of the deformed panel wall 5,
The depressed displacement 5 indicates the displacement state of the deformable panel wall 5 corresponding to the change in the pressure in the bottle 1.

As is apparent from FIG. 4, the effect of absorbing the pressure change in the bottle 1 is caused by the elongation and deformation of the vertically long ribs 6 in the deformed panel wall 5 between the pair of ribs 6. It can be fully understood that a large change in the internal volume of the bottle 1 can be obtained with the displacement of the deformable panel wall 5 since the whole is achieved by the displacement that protrudes or collapses.

In the bottle body 1 of the embodiment shown in the figure, since the height of the lower half 4 provided with the deformed panel wall 5 is small, the total surface area of the entire deformed panel wall 5 is small. Since the amount of pressure change absorption in the deformed panel wall 5 is large, it is possible to exhibit sufficient ability to absorb a large pressure change.

[0025]

According to the present invention, the following effects can be obtained by employing the above-described configuration. By providing the elongated ribs on the deformed panel wall, the entire deformed panel wall can be displaced so as to protrude or depress in accordance with the elongation deformation of the elongated ribs. Since it is possible to obtain the ability to absorb a large change in pressure as compared with the case where the bottle collapses, it is possible to reliably prevent the bottle from being improperly deformed due to the change in internal pressure.

Also, since the vertically long ribs are positioned so as to be sandwiched on both sides of the vertically long, flat, columnar side walls of the bottle body wall, the vertically long ribs extend vertically to the column side walls. This will provide structural reinforcement against the pressure load from the body, and will not cause a reduction in buckling strength due to the provision of the deformed panel wall in the trunk, and will not cause a decrease in the torso wall portion provided with the deformed panel wall. Buckling strength can be increased.

When forming a bottle exhibiting the same pressure change absorbing ability, the size of the deformed panel wall can be made smaller than that of the conventional one, so that the height of the body wall portion on which the deformed panel wall is provided is increased. Thus, it is possible to obtain a bottle having a small design and a novel design having a novel appearance in which the overall design of the bottle is different from that of the conventional bottle.

Since the vertically elongated ribs are provided on the inner peripheral surfaces of both side edges of the deformed panel wall provided in the depressed shape so as to protrude over substantially the entire length range of the deformed panel wall, the reduced-pressure deformed bottle is formed. When the torso is viewed from the lateral direction, the depressed state of the deformed panel wall is hidden by the protruding vertical ribs, and the protruding surface of the vertical ribs forms a contour line. It is possible to prevent the appearance of the bottle from becoming inferior and to prevent the disadvantage that the appearance of the bottle becomes poor due to the provision of the deformed panel wall, and to obtain a bottle having a good appearance.

[Brief description of the drawings]

FIG. 1 is an overall front view showing an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of an essential part taken along line AA in FIG.

FIG. 3 is a cross-sectional view of a main part of the embodiment shown in FIG. 1;

FIG. 4 is a cross-sectional view of a main part taken along the line BB in FIG. 1;

[Explanation of symbols]

 1: Bottle 2: Body 3: Upper half of body 4: Lower half of body 5: Deformed panel wall 5 ': Panel wall displaced and protruded 5 ": Panel wall displaced and displaced 6: Vertical rib 6': Projection Rib at the time of displacement 6 ": Rib at the time of depression displacement 7: Column-shaped side wall 8: Central peripheral groove 9: Rib peripheral groove 10: Shoulder 11: Neck and neck

Claims (3)

(57) [Claims] 1. A plurality of reinforcing rib circumferential grooves are arranged in a multi-stage shape in the upper half of the body with a central circumferential groove provided in the middle of the body of the bottle-shaped hollow container. A mouth-and-neck portion is erected and connected to the rib circumferential groove via a conical cylindrical shoulder portion, and a plurality of vertically elongated flat panel-shaped deformed panel walls are equally spaced in the circumferential direction in the lower half of the body portion. In a synthetic resin hollow container arranged side by side in a depressed shape, at least at the height of the lower half of the body of the hollow container to form a deformed panel wall having an elliptical shape, and
On the inner peripheral surface along both side edges of the deformed panel wall, vertically elongated ribs protruding outward to a height that becomes an outer line viewed from the lateral direction of the body are provided. The ribs are formed in an arc shape by curving both ends of the ribs inward, and the ribs are formed on both sides of a columnar side wall formed by a simple flat plate through a part of the panel wall. A biaxially stretch blow-molded polyethylene terephthalate resin hollow container characterized in that it has a structure that can be sandwiched from above to increase buckling strength. 2. A plurality of reinforcing rib circumferential grooves are arranged in a multi-stage shape in the upper half of the body with a central circumferential groove provided in the middle of the body of the bottle-shaped hollow container. A mouth-and-neck portion is erected and connected to the rib circumferential groove via a conical cylindrical shoulder portion, and a plurality of vertically elongated flat panel-shaped deformed panel walls are equally spaced in the circumferential direction in the lower half of the body portion. In the synthetic resin hollow containers arranged side by side in the depressed shape, the height of the lower half of the hollow container including the bottom where the deformed panel wall of the lower half is provided is higher than the height of the upper half of the hollow including the shoulder. And the deformed panel wall is formed in an elliptical shape, and the inner peripheral surface along both side edges of the deformed panel wall is an outer line viewed from the lateral direction of the trunk. Vertical ribs protruding outward to a height of approximately the same height are formed within the height range of the deformed panel wall, and both ends of the ribs are bent inward. It is bent and formed into an arc shape, and the buckling strength is increased by a structure in which the ribs sandwich a columnar side wall having a simple flat plate from both sides through a part of the panel wall. A hollow container made of polyethylene terephthalate resin formed by biaxial stretch blow molding. 3. The biaxially stretch blow-molded article according to claim 1, wherein the deformed panel wall provided in the lower half of the body of the hollow container is composed of six panel walls. Hollow container made of polyethylene terephthalate resin.