JP2007269359A - Synthetic resin-made round bottle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a synthetic resin-made round bottle having high vacuum strength by suppressing any local buckling deformation in a vacuum state in a barrel having an inclined panel. <P>SOLUTION: A plurality of inclined panels 12 which are inclined in a predetermined direction are formed at a cylindrical barrel 4 in parallel in the peripheral direction in a recessed manner so as to surround the circumference thereof by a stepped part 10. An inclined pillar 11 is formed between the inclined panels adjacent to each other. A recessed groove 15 is formed at a predetermined corner out of four upper and lower corners of the inclined panel adjacent to the base end of the stepped part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is typified by a polyethylene terephthalate (hereinafter referred to as PET) resin biaxially stretched blow-molded bottle in which a plurality of inclined panels are formed in parallel in the circumferential direction on the body portion to constitute a reduced pressure absorption function portion. The present invention relates to the structure of a synthetic resin round bottle.

  A synthetic resin round bottle is known in which a plurality of inclined panels inclined at a fixed inclination angle are arranged in parallel in the circumferential direction on the body portion to constitute a reduced pressure absorption function portion.

The round bottle formed with this inclined panel is not only deformed inwardly by bending down the inclined panel due to the occurrence of decompression in the bottle, but also due to reduced diameter deformation due to torsional deformation of the body portion provided with the inclined panel. , Exerts a greater vacuum absorption function. Further, the rib-like function is exhibited by the column part between the inclined panels accompanying the curved depression deformation of the inclined panel, and a strong resistance against the external force from the lateral direction can be exhibited.
Japanese Utility Model Publication No. 6-59207

  However, in the round bottle that constitutes the reduced pressure absorption function part with the inclined panel and the column part, a larger reduced pressure absorption function is exhibited due to the reduced diameter deformation accompanying torsional deformation in the reduced pressure state as described above. The problem is related to the improvement of the vacuum absorption function that the wall part at the periphery of the inclined panel including the column part is locally buckled and deformed due to this torsional deformation, and the original shape cannot be restored. There is.

  Therefore, the present invention was devised to solve the above-mentioned problems of the prior art, and it is a technical problem to suppress local buckling deformation in a reduced pressure state in a body portion provided with an inclined panel. Therefore, an object of the present invention is to provide a synthetic resin round bottle having a greater decompression strength.

Among the present invention for solving the above technical problems, the means of the invention according to claim 1 is:
Forming a plurality of inclined panels inclined in a certain direction in a cylindrical body portion in a circumferential manner in a depressed shape so as to surround the periphery with a stepped portion,
To make an inclined column part between adjacent inclined panels,
Forming a recessed groove adjacent to the base end of the step at a predetermined corner of the four corners of the tilt panel,
It is in.

  The inventors of the present application conducted a stress analysis on a round bottle having an inclined panel and conducted a test related to reduced pressure strength, and as the degree of reduced pressure was increased, along with the twisted diameter reduction deformation, A large tensile stress acts along the inclined direction, and stress concentration occurs in the vicinity of the step rising base end of the upper and lower corners of the inclined panel, and the peripheral wall portion including the column portion in the vicinity of the stress concentration portion. Has been found to be locally buckled and deformed, resulting in the construction of claim 1.

  According to the above configuration of the first aspect, a reinforcing effect is exhibited by the concave groove by forming the concave groove adjacent to the step rising base end portion at the corner where the stress concentration occurs. As a result, local buckling deformation of the peripheral wall portion including the column portion in the vicinity of the stress concentration portion can be effectively suppressed.

Note that the inclined panel shape is basically a parallelogram shape when viewed from the front, and there are a total of four corners at the top and bottom, but it is not always necessary to form grooves on all corners. By referring to the stress analysis result, it is also possible to form the concave groove only in the corner portion where the stress concentration is particularly large.
From this point of view, in claim 1, it is described as “at a predetermined corner of the four corners of the upper and lower sides.

  According to a second aspect of the present invention, in the first aspect of the invention, a concave groove is formed in a corner portion that forms an acute angle in the corner portion.

As described above, according to the stress analysis, when the degree of decompression is increased, a large tensile stress is applied to the column portion along the inclination direction along with the twisted diameter reduction deformation.
Due to the above action, the inclined panel shape is basically a parallelogram when viewed from the front, and there are a total of four corners at the top and bottom, among which stress at the corners that form an acute angle in particular. Since the concentration increases, by forming a concave groove in the corner portion that forms the acute angle according to the above-described configuration according to claim 2, local buckling deformation of the peripheral wall portion including the column portion in the vicinity of the stress concentration is achieved. Can be more effectively suppressed.
In addition, although the corner | angular part which forms an acute angle exists up and down, since the grade of stress concentration differs also in these upper and lower corner parts by the whole shape of a bottle, a ditch | groove is necessarily formed in the upper and lower corner parts. There is no need, and it is possible to form a concave groove only at one corner with reference to the stress analysis result.

  According to a third aspect of the present invention, in the first or second aspect of the invention, the corners of the inclined panel are rounded to form an arc shape, and the width of the upper base end and the lower base end of the column part is widened. To be configured to.

  According to the above configuration of the third aspect, stress concentration at the corner portion can be alleviated by chamfering the corner portion of the inclined panel into an arc shape. Further, by configuring the column portion so as to widen the upper base end portion and the lower base end portion, the stress level in the upper end portion of the column portion or in the vicinity of the lower end portion can be effectively reduced.

  According to a fourth aspect of the present invention, in the first, second, or third aspect of the invention, circumferential grooves are formed at the upper end and the lower end of the body portion, and annular portions are left at the upper end and the lower end between the circumferential grooves. 6 to 8 inclined panels are formed over substantially the entire height range between the circumferential grooves.

  The said structure of Claim 4 is related with the shape of a more specific trunk | drum, and does not impair the external appearance as a round bottle by forming 6-8 pieces of inclination panels, and is the abbreviation of a trunk | drum. Since the inclined panel is formed over the entire height range, a sufficiently large vacuum absorbing function can be exhibited.

In addition, the progress of volume reduction deformation and bulging deformation during decompression or pressurization can be effectively stopped by the circumferential grooves formed in the upper and lower ends of the body part and the annular part, as a round bottle Can be secured and maintained without impairing the appearance and functions of the production line.

Since the present invention has the above-described configuration, the following effects can be obtained.
In the first aspect of the invention, a rib-like reinforcing effect is exhibited by forming a concave groove adjacent to the stepped base end at the corner where stress concentration occurs, and the column portion is It is possible to suppress local buckling deformation of the including peripheral wall portion.

  In the invention according to claim 2, when the degree of decompression increases, the stress concentration at the corner portion forming an acute angle increases with the twisted diameter reduction deformation. By forming the groove, local buckling deformation of the peripheral wall portion including the column portion can be more effectively suppressed.

  In the invention described in claim 3, by concentrating the corners in an arc shape, stress concentration at the corners can be alleviated, and the widths of the upper base end and the lower base end of the column part are widened. Thus, the stress level at the upper end portion or the lower end portion of the column portion can be reduced.

  In the invention according to claim 4, by forming 6 to 8 inclined panels, the inclined panel is formed over substantially the entire height range of the body without impairing the appearance of the round bottle. Therefore, a sufficiently large reduced pressure absorption function can be exhibited. In addition, the progress of volume reduction deformation and bulging deformation during decompression or pressurization can be effectively stopped by the circumferential grooves formed in the upper and lower ends of the body and the annular portion, as a round bottle Can be secured and maintained without impairing the appearance and functions of the production line.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the accompanying drawings.
1 to 4 show an embodiment of the synthetic resin round bottle of the present invention,
1 is an overall front view of the bottle, FIG. 2 is a plan sectional view taken along line AA in FIG. 1, FIG. 3 is a development view of the vicinity of three adjacent inclined panels 12, and FIG. It is a longitudinal cross-sectional view shown along a BB line.

  The round bottle 1 of the present embodiment is a biaxial stretch blow molded product made of PET resin and has a nominal capacity of 500 ml. A cylindrical body 4 is connected to the upper end of the body 4 via a substantially hemispherical arc wall-shaped shoulder 3 with a thread and a neck ring on the outer peripheral surface. The bottom tube part 2 and the bottom part 5 are provided at the lower end of the body part 4 and are continuously provided with the center part of the bottom wall recessed into the bottle.

  Circumferential grooves 17 that function as peripheral ribs are formed at the upper end and the lower end of the body part 4, leaving the annular portions 18 directly below the upper peripheral groove 17 and directly above the lower peripheral groove 17, Eight inclined panels 12 are formed in parallel in the circumferential direction so as to be inclined to the right so as to be surrounded by the stepped portion 10 and to be depressed. In addition, eight column portions 11 that are similarly inclined upward are left between the adjacent inclined panels 12.

The shape of the inclined panel 12 is basically a parallelogram when viewed from the front, and there are a total of four corners 13 at the top and bottom. In this embodiment, the corners 13 are rounded. The upper end portion and the lower end portion are formed in an arc shape. Further, by making the corner portion 13 into an arc shape, the width is wide at the upper base end portion and the lower base end portion of the column portion 11.
In addition, the upper end and lower end of this pillar part 11 are connected to the annular part 18 via the rising horizontal step part 14, and the reduced pressure absorption function constituted by the inclined panel 12 and the pillar part 11 in the decompressed state. The volume reduction deformation of the portion is prevented from progressing to the circumferential groove 17.

Of the four corner portions 13, the upper right corner portion 13UR and the lower left corner portion 13LL are adjacent to the rising base end portion of the step portion 10 along a circularly chamfered shape. Thus, a concave groove 15 is formed. (See Figs. 3 and 4)
The upper right corner portion 13UR and the lower left corner portion 13LL correspond to the corner portion 13s that forms an acute angle among the four corner portions 13. (See Figure 3)

Here, according to the stress analysis in the reduced pressure state, in the round bottle that constitutes the reduced pressure absorption function portion with the inclined panel 12 and the inclined column portion 11 as in the present embodiment, when the degree of reduced pressure increases, The torsional deformation is performed along the inclined column part 11, and the body part 4 is deformed to reduce its diameter, so that an effective decompression absorption function is exhibited.
At that time, a large tensile stress acts on the column part 11 along the inclination direction, and a relatively large stress concentration occurs particularly in the vicinity of the corner part 13s forming the acute angle described above. For example, it is indicated by hatching in FIG. In the region R, the wall tends to be bent locally, and buckling deformation tends to occur. However, the concave groove 15 formed in the corner portion 13UR exhibits a reinforcing effect against such deformation, The occurrence of bending deformation can be effectively suppressed.

  In this embodiment, the concave groove 15 is formed in the corner portion 13UR and the corner portion 13LL. However, the concave groove 15 can be formed only in the corner portion 13UR, for example, depending on the result of the stress analysis or the pressure reduction test. Further, for example, the concave groove 15 can be formed along the step portion 10 in the upper end portion of the inclined panel 12 including the left and right corner portions 13 and / or the entire lower end portion.

  As mentioned above, although embodiment of this invention and its effect were demonstrated about the Example, this invention is not limited to the said Example. The round bottle of the present invention is not limited to a biaxial stretch blow molded product made of PET resin, and the number of inclined panels formed is not limited to this embodiment.

  As described above, the synthetic resin round bottle of the present invention exhibits a reduced pressure absorption function using an inclined panel, and is expected to be used in a wide range of applications as a round bottle with an excellent reduced pressure absorption function. The

It is a whole front view which shows one Example of the bottle of this invention. It is a plane sectional view shown along the AA line in FIG. FIG. 2 is a development view of the vicinity of three adjacent inclined panels in FIG. 1. It is a longitudinal cross-sectional view shown along the BB line in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1; Bottle 2; Mouth part 3; Shoulder part 4; Trunk part 5; Bottom part 10; Step part 11; Pillar part 12; Inclined panel 13; Corner part 13UR, 13LL; Portion 14; horizontal step portion 15; concave groove 17; circumferential groove 18; annular portion R;

Claims (4)

In the cylindrical body (4), a plurality of inclined panels (12) inclined in a certain direction are surrounded by a stepped part (10), and are formed in parallel in the circumferential direction in a depressed shape, and adjacent to each other. A column portion (11) inclined between the inclined panels (12) is used, and the step portion (10) is formed at a predetermined corner portion (13) of four corner portions (13) of the upper and lower sides of the inclined panel (12). ) A synthetic resin round bottle with a recessed groove (15) adjacent to the rising base end. The synthetic resin round bottle according to claim 1, wherein a concave groove (15) is formed in a corner (13s) forming an acute angle in the corner (13). The corner portion (13) of the inclined panel (12) is chamfered into an arc shape, and the width of the upper base end portion and the lower base end portion of the column portion (11) is widened. Synthetic plastic round bottle. A circumferential groove (17) is formed at the upper end and the lower end of the body (4), and the annular groove (17) is left at the upper and lower ends between the circumferential grooves (17). The synthetic resin round bottle according to claim 1, 2 or 3, wherein 6 to 8 inclined panels (12) are formed over substantially the entire height range.

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