ROUND BLOW BOTTLE
The present invention is a round blow bottle in which a mouth portion, a shoulder portion, a body portion, and a bottom portion are connected in this order from top to bottom along a bottle axis O direction, and is formed in a bottomed cylindrical shape using a synthetic resin material, in which a bottom wall portion of the bottom portion includes a ground contact portion and a depressed portion, and a peripheral wall portion of the depressed portion includes a lower portion and an upper portion, and a step portion protruding inward in the radial direction is formed at a connecting portion between the lower portion and the upper portion.
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Priority is claimed on Japanese Patent Application No. 2023-063351, filed Apr. 10, 2023, the content of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION Field of the InventionThe present invention relates to a round blow bottle.
Description of Related ArtIn the related art, as shown in Japanese Unexamined Patent Publication No. 10-139029, as a round bottle made of a synthetic resin material and formed in a bottomed cylindrical shape, for example, a configuration in which a bottom wall portion of a bottom portion includes a ground contact portion located on an outer peripheral edge portion, and a depressed portion is located on an inner side in a radial direction than the ground contact portion, and which is formed in a topped cylindrical shape that is recessed upward is known.
However, in the round blow bottle of the related art, at the time of blow molding, a flow resistance of the resin material is high in a portion of an inner surface of a cavity in which the ground contact portion is formed, so-called thickening occurs, and there is a likelihood of an occurrence of a difference in wall thickness with the ground contact portion as a boundary. In this case, it becomes difficult to make the wall thickness of the ground contact portion uniform over an entire length in a circumferential direction, and when filling with contents, an amount of deformation of the ground contact portion is unlikely to be uniform over the entire length in the circumferential direction, and there is a likelihood of a difficulty in ensuring ground contact stability.
In particular, when trying to make the round blow bottle be lightweight, the amount of deformation of the ground contact portion will increase when filling the bottle with contents. Therefore, there is a likelihood that this problem will become more obvious.
The present invention provides a round blow bottle in which the wall thickness of the ground contact portion can be made uniform over the entire length in the circumferential direction.
SUMMARY OF THE INVENTIONA first aspect of the present invention is a round blow bottle in which a mouth portion, a shoulder portion, a body portion, and a bottom portion are connected in this order from top to bottom along a bottle axis direction, and is formed in a bottomed cylindrical shape using a synthetic resin material, in which a bottom wall portion of the bottom portion includes a ground contact portion which is located on an outer peripheral edge portion, and a depressed portion which is located on an inner side in a radial direction than the ground contact portion, and which is formed in a topped cylindrical shape that is recessed upward, a peripheral wall portion of the depressed portion extends inward in the radial direction as it goes upward, the peripheral wall portion of the depressed portion includes a lower portion connected to the ground contact portion, and an upper portion connected to a top wall portion of the depressed portion, the lower portion has a curved shape that is recessed outward in the radial direction in a vertical cross-sectional view along the vertical direction, and a step portion protruding inward in the radial direction is formed at a connecting portion between the lower portion and the upper portion, and the step portion extends continuously over an entire length in a circumferential direction.
In the peripheral wall portion of the depressed portion, the connecting portion between the lower portion and the upper portion has a step portion protruding inward in the radial direction, and the step portion extends continuously over the entire length in the circumferential direction. As a result, at the time of blow molding, the flow resistance of the resin material is increased in the portion of the inner surface of the cavity that is located on the inner side in the radial direction than the portion, in which the ground contact portion is to be molded, and the step portion will be molded, thereby creating a so-called thickening. As a result, at the time of the blow molding, the resin material is sufficiently stretched until reaching the portion of the inner surface of the cavity in which the ground contact portion is to be molded. Accordingly, it is possible to make it difficult for wall thickness differences to occur with the ground contact portion as a boundary, and it is possible to easily make the wall thickness of the ground contact portion uniform over the entire length in the circumferential direction.
In addition, in order to stretch the resin material sufficiently until reaching the portion of the inner surface of the cavity in which the ground contact portion is to be molded at the time of the blow molding, if the diameter of the top wall portion of the depressed portion and the width (size in the radial direction) of the ground contact portion are increased instead of providing the step portion, when filling the contents, at the top wall portion of the depressed portion or the ground contact portion, the top wall portion of the depressed portion and the ground contact portion bulge toward the outside of the round blow bottle, making it easy for so-called bottoming out to occur.
Furthermore, when the diameter of the top wall portion of the depressed portion is increased, for example, there is a possibility that the peripheral wall portion of the depressed portion or the ground contact portion may become too thin and cause molding defects such as tearing.
As described above, it is possible to easily form a round blow bottle in which the wall thickness of the ground contact portion can be made uniform over the entire length in the circumferential direction, while suppressing the tendency for the contents to fall to the bottom when filling.
According to a second aspect of the present invention, in the round blow bottle of the first aspect, the upper portion has a linear shape in a vertical cross-sectional view along the vertical direction.
The upper portion of the peripheral wall portion of the depressed portion has a linear shape in a vertical cross-sectional view along the vertical direction. As a result, at the time of the blow molding, it is possible to reliably suppress the flow resistance of the resin material at a portion of the inner surface of the cavity that is located on the inner side in the radial direction than the portion, in which the step portion is molded, and that molds the upper portion of the peripheral wall portion of the depressed portion, and the wall thickness of the ground contact portion can be made uniform over the entire length in the circumferential direction.
As described above, it is possible to easily form the round blow bottle in which the wall thickness of the ground contact portion can be made uniform over the entire length in the circumferential direction.
According to the first and second aspects of the present invention, the wall thickness of the ground contact portion can be made uniform over the entire length in the circumferential direction.
Hereinafter, a bottle according to an embodiment of the present invention will be described with reference to the drawings.
A round blow bottle 1 according to the present embodiment includes a mouth portion 11, a shoulder portion 12, a body portion 13, and a bottom portion 14, as shown in
Hereinafter, the common axis will be referred to as a bottle axis O, the mouth portion 11 side along the bottle axis O will be referred to as an upper side, the bottom portion 14 side along the bottle axis O will be referred to as a lower side, and a direction along the bottle axis O will be referred to as a vertical direction. Further, a direction intersecting the bottle axis O as viewed from the vertical direction is referred to as a radial direction, and a direction of revolving around the bottle axis O from the vertical direction is referred to as a circumferential direction.
The round blow bottle 1 is blow molded and formed in a bottomed cylindrical shape by a synthetic resin material. The round blow bottle 1 is formed on the basis of a preform formed in a bottomed cylindrical shape, for example, by injection molding.
For example, the round blow bottle 1 is used so that in a state of being filled with contents at a high temperature (for example, about 40° C. to 95° C.), an inert gas is blown into the head space to replace the air in the head space with the inert gas, and then, the inside of the mouth portion 11 is sealed.
The mouth portion 11, the shoulder portion 12, the body portion 13, and the bottom portion 14 are formed so that the cross-sectional shape perpendicular to the bottle axis O is circular.
A cap (not shown) is attached to the mouth portion 11.
The shoulder portion 12 extends outward in the radial direction as it goes downward. A lower end portion of the shoulder portion 12 has a curved shape that protrudes outward in the radial direction in a vertical cross-sectional view along the vertical direction. A portion of the shoulder portion 12 located above a lower end portion has a linear shape in the vertical cross-sectional view. A size of the lower end portion of the shoulder portion 12 in the vertical direction is smaller than a size of a portion located above the lower end portion in the vertical direction.
The body portion 13 extends straight in the vertical direction.
The bottom portion 14 includes a cylindrical heel portion 17 whose upper end opening portion is connected to a lower end opening portion of the body portion 13, and a bottom wall portion which closes the lower end opening portion of the heel portion 17 and whose outer peripheral edge portion is a ground contact portion 18. The bottom portion 14 is formed in a cup shape.
The heel portion 17 extends inward in the radial direction as it goes downward. The upper end portion of the heel portion 17 is a portion of the bottom portion 14 that has the largest outer diameter.
A maximum value of the outer diameter of the bottom portion 14 is 30 mm or more and 130 mm or less, and a weight of the bottom portion 14 is 2.0 g or more and 20 g or less. A ratio between the weight of the bottom portion 14 and the maximum value of the outer diameter of the bottom portion 14 may be 0.06 g/mm or more and 0.20 g/mm or less.
The ground contact portion 18 is formed in an annular shape that has a width in the radial direction, and extends continuously over an entire length in the circumferential direction. The width of the ground contact portion 18 in the radial direction is 15% or less of the diameter (50 mm in the shown example) at the inner peripheral edge of the ground contact portion 18. Further, the ground contact portion 18 may be formed in a linear shape having substantially no width in the radial direction.
In the bottom wall portion, a depressed portion 19 that is recessed upward is formed in a portion located on the inner side in the radial direction than the ground contact portion 18. The depressed portion 19 has a top wall portion 20 and a peripheral wall portion 21. The depressed portion 19 is formed in a topped cylindrical shape and is disposed coaxially with the bottle axis O.
The top wall portion 20 is formed in a disk shape with front and back surfaces facing in the vertical direction. The top wall portion 20 is located above the upper end portion of the heel portion 17. A diameter (16 mm in the shown example) of the top wall portion 20 is 50% or less of a diameter at the inner peripheral edge of the ground contact portion 18.
The peripheral wall portion 21 extends inward in the radial direction as it goes upward. As shown in
The lower portion 22 has a curved shape that is recessed outward in the radial direction in a vertical cross-sectional view along the vertical direction. The lower portion 22 is connected to the ground contact portion 18 via a lower connecting portion that has a curved shape protruding inward in the radial direction in the longitudinal cross-sectional view. In the longitudinal cross-sectional view, the radius of curvature of a lower side portion of the lower portion 22 that is continuous to the lower connecting portion 25 is smaller than the radius of curvature of the upper portion that is continuous to a step portion 24, which will be described below.
The step portion 24 protruding inward in the radial direction is formed at the connecting portion between the lower portion 22 and the upper portion 23. The step portion 24 is provided at a central portion of the peripheral wall portion 21 in the vertical direction. The step portion 24 extends continuously over the entire length in the circumferential direction. The step portion 24 has a curved shape that protrudes inward in the radial direction in the longitudinal cross-sectional view. The step portion 24 faces inward in the radial direction and protrudes diagonally downward. In the longitudinal cross-sectional view, the radius of curvature of the step portion 24 is smaller than the radius of curvature of the lower side portion of the lower portion 22.
The top portion of the step portion 24 is located on the inner side in the radial direction than a straight line that connects the inner peripheral edge of the ground contact portion 18 and the outer peripheral edge of the top wall portion 20 in the longitudinal cross-sectional view. A diameter (inner diameter) at the top portion of the step portion 24 is 30% or more and 70% or less of the diameter at the inner peripheral edge of the ground contact portion 18. In the shown example, the diameter at the top portion of the step portion 24 is 30 mm. A distance in the vertical direction from the ground contact portion 18 to the top portion of the step portion 24 is 30% or more and 70% or less (47% in the shown example) of a distance in the vertical direction from the ground contact portion 18 to the top wall portion 20.
The upper portion 23 has a linear shape in a vertical cross-sectional view along the vertical direction. The upper portion 23 is connected to the top wall portion 20 via an upper connecting portion 26 that has a curved shape recessed outward in the radial direction in the longitudinal cross-sectional view.
Further, in the longitudinal cross-sectional view, the upper portion 23 may have a curved shape protruding outward in the radial direction, or may have a curved shape protruding inward in the radial direction.
As explained above, according to the round blow bottle 1 according to the present embodiment, in the peripheral wall portion 21 of the depressed portion 19, the connecting portion between the lower portion 22 and the upper portion 23 has a step portion 24 protruding inward in the radial direction, and the step portion 24 extends continuously over the entire length in the circumferential direction. As a result, at the time of blow molding, the flow resistance of the resin material is increased in the portion of the inner surface of the cavity that is located on the inner side in the radial direction than the portion, in which the ground contact portion 18 is to be molded, and that molds the step portion 24, thereby creating a so-called thickening. As a result, at the time of the blow molding, the resin material is sufficiently stretched until reaching the portion of the inner surface of the cavity in which the ground contact portion 18 is to be molded, it is possible to make it difficult for wall thickness differences to occur with the ground contact portion 18 as a boundary, and it is possible to easily make the wall thickness of the ground contact portion 18 uniform over the entire length in the circumferential direction.
In addition, in order to stretch the resin material sufficiently until reaching the portion of the inner surface of the cavity in which the ground contact portion 18 is to be molded at the time of the blow molding, if the diameter of the top wall portion 20 of the depressed portion 19 and the width (size in the radial direction) of the ground contact portion 18 are increased instead of providing the step portion 24, when filling the contents, at the top wall portion 20 of the depressed portion 19 and the ground contact portion 18, the top wall portion 20 of the depressed portion 19 and the ground contact portion 18 bulge toward the outside of the round blow bottle 1, making it easy for so-called bottoming out to occur. Furthermore, when the diameter of the top wall portion 20 of the depressed portion 19 is increased, for example, there is a possibility that the peripheral wall portion 21 of the depressed portion 19 or the ground contact portion 18 may become too thin and cause molding defects such as tearing.
As described above, it is possible to easily form a round blow bottle in which the wall thickness of the ground contact portion 18 can be made uniform over the entire length in the circumferential direction, while suppressing the tendency for the contents to fall to the bottom when filling.
The upper portion 23 of the peripheral wall portion 21 of the depressed portion 19 has a linear shape in a vertical cross-sectional view along the vertical direction. As a result, at the time of the blow molding, it is possible to reliably suppress the flow resistance of the resin material at a portion of the inner surface of the cavity that is located on the inner side in the radial direction than the portion, in which the step portion 24 is molded, and that molds the upper portion 23 of the peripheral wall portion 21 of the depressed portion 19, and the thickness of the ground contact portion 18 can be made uniform over the entire length in the circumferential direction.
As described above, it is possible to easily form the round blow bottle 1 in which the wall thickness of the ground contact portion can be made uniform over the entire length in the circumferential direction.
Further, the technical scope of the present invention is not limited to the above-described embodiments, and various changes can be made without departing from the spirit of the present invention.
The synthetic resin material that forms the round blow bottle 1 is, for example, polyethylene terephthalate, polyethylene naphthalate, amorphous a polyester, a polyolefin, or a blend thereof or the like, and they may be changed as appropriate.
The round blow bottle 1 is not limited to a single layer structure, and may be a laminated structure having an intermediate layer. Examples of the intermediate layer include a layer made of a resin material having gas barrier properties, a layer made of a recycled material, a layer made of a resin material having oxygen absorption properties, and the like.
In addition, the components in the present embodiments described above may be replaced with known components as appropriate without departing from the spirit of the present invention, and the present embodiments and the modified examples may be combined as appropriate.
Claims
1. A round blow bottle in which a mouth portion, a shoulder portion, a body portion, and a bottom portion are connected in this order from top to bottom along a bottle axis direction, and which is formed in a bottomed cylindrical shape using a synthetic resin material,
- wherein a bottom wall portion of the bottom portion includes
- a ground contact portion which is located on an outer peripheral edge portion, and
- a depressed portion which is located on an inner side in a radial direction than the ground contact portion, and which is formed in a topped cylindrical shape that is recessed upward,
- a peripheral wall portion of the depressed portion extends inward in the radial direction as it goes upward,
- the peripheral wall portion of the depressed portion includes:
- a lower portion connected to the ground contact portion, and
- an upper portion connected to a top wall portion of the depressed portion,
- the lower portion has a curved shape that is recessed outward in the radial direction in a vertical cross-sectional view along the vertical direction, and
- a step portion protruding inward in the radial direction is formed at a connecting portion between the lower portion and the upper portion, and
- the step portion extends continuously over an entire length in a circumferential direction.
2. The round blow bottle according to claim 1,
- wherein the upper portion has a linear shape in a vertical cross-sectional view along the vertical direction.
Type: Application
Filed: Mar 29, 2024
Publication Date: Oct 10, 2024
Applicant: YOSHINO KOGYOSHO CO., LTD. (Tokyo)
Inventors: Hiroaki IMAI (Matsudo-shi), Taichi ASADA (Matsudo-shi)
Application Number: 18/621,797
