Synthetic resin container

Abstract

To provide a new synthetic resin container that hardly causes plastic deformation in a columnar part between reduced pressure absorption panels on the occurrence of decompression.SOLUTION: A synthetic resin container 100 of the present disclosure comprises a mouth 2 which serves as a bung hole for contents, a trunk part 4 which continues into the mouth 2 via a shoulder part 3, and a bottom 5 for closing the lower end of the trunk part 4. In the synthetic resin container 100, the trunk part 4 has a plurality of reduced pressure absorption panels 11 that is arranged in a circumferential direction, and a columnar part 16 that is provided in a circumferential position between the two adjacent reduced pressure absorption panels 11 of the plurality of reduced pressure absorption panels 11. At least one of upper and lower parts of the columnar part 16 has columnar part fillets 15 that are formed by being chamfered at edges on both the circumferential sides of the columnar part 16.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a bottle-shaped synthetic resin container having a mouth portion serving as an outlet for the contents, a body portion connected to the mouth portion via a shoulder portion, and a bottom portion closing the lower end of the body portion, and more particularly to one in which a decompression absorption panel is provided in the body portion.

Background Art

[0002] Synthetic resin containers typified by bottles made of stretched polypropylene (OPP) or polyethylene terephthalate (PET) are lightweight, easy to handle, excellent in storage stability of contents, and inexpensive in cost, and thus are used in various applications such as for beverages, foods, and cosmetics.

[0003] For example, Patent Document 1 discloses a container having a substantially circular shape in plan view. This container is a synthetic resin container having a mouth portion serving as an outlet for the contents, a body portion connected to the mouth portion via a shoulder portion, and a bottom portion closing the lower end of the body portion, and a decompression absorption panel is formed in a recessed shape in the body portion. For example, when the mouth portion is closed with a cap after the contents are filled at a high temperature, a decompression may occur in the container as the contents cool, and the body portion may be greatly deformed. By providing a decompression absorption panel in the body portion to address this problem, the decompression in the container can be absorbed by the deformation (decompression deformation) of the decompression absorption panel, and the container can be prevented from being deformed illegally. Further, as the decompression absorption panel undergoes decompression deformation, the column portion formed between adjacent decompression absorption panels also deforms so as to "creak".

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in the case of a downsized PET bottle with a content volume of 350 [ml] or 280 [ml], the area of the decompression absorption panel is small, and the vertical length of the column portion provided at the circumferential position between the decompression absorption panels is also short. For this reason, in the downsized container, the column portion tends to be suppressed from "bending" inward in the radial direction. If excessive bending stress is applied to the column portion in the downsized container and it breaks (plastic deformation) occurs, it is difficult to restore and it may lead to poor appearance. Therefore, there was room for improvement in this regard.

[0006] The present disclosure has been made in view of such problems, and an object thereof is to provide a new synthetic resin container in which plastic deformation is less likely to occur in the column portion between the decompression absorption panels when decompression occurs.

Means for Solving the Problems

[0007] In order to solve the above problems, the synthetic resin container of the present disclosure is [1] A synthetic resin container including a mouth portion serving as an outlet for the content, a body portion connected to the mouth portion via a shoulder portion, and a bottom portion closing the lower end of the body portion, The body portion has a plurality of decompression absorption panels arranged in the circumferential direction, and a column portion provided at a circumferential position between two adjacent decompression absorption panels among the plurality of decompression absorption panels, At least one of the upper and lower portions of the column portion has a column portion fillet formed as a chamfer at the edge portions on both sides in the circumferential direction of the column portion, which is characterized.

[0008] Further, the synthetic resin container of the present disclosure is [2] In the configuration described in [1] above, the column portion fillet is provided at the upper portion of the column portion, the column portion fillet extends in the vertical direction from a position closer to the upper side than the vertical center position of the column portion to the vicinity of the upper end portion of the column portion, and it is preferable that the width of the chamfer is maximum at a position closer to the upper side than the vertical center position of the column portion fillet.

[0009] Further, the synthetic resin container of the present disclosure is [3] In the configuration described in the above [1] or [2], the column fillet is provided at the lower part of the column, and the column fillet extends in the vertical direction from a position closer to the lower side than the central position in the vertical direction of the column to the vicinity of the lower end of the column. It is preferable that the chamfer width is maximized at a position closer to the lower side than the central position in the vertical direction of the column fillet.

[0010] In addition, the synthetic resin container of the present disclosure [4] In the configuration described in any one of the above [1] to [3], the column fillet preferably has a chamfer with a circumferential chamfer width larger than the chamfer width in the depth direction of the decompression absorption panel at the vertical position where the chamfer width is maximized.

Effect of the Invention

[0011] According to the present disclosure, it is possible to provide a new synthetic resin container in which plastic deformation is less likely to occur in the column portion between the decompression absorption panels when decompression occurs.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Mode for Carrying Out the Invention

[0013] Hereinafter, the present disclosure will be more specifically illustrated with reference to the drawings.

[0014] The synthetic resin container 100, which is an embodiment of the present disclosure shown in Fig. 1, is for containing beverages such as fruit juice drinks and tea, as well as seasonings such as soy sauce, vinegar, and sauce as its contents, and is compatible with high-temperature filling in which the contents are filled in a high-temperature state heated to a predetermined temperature. Further, it is not limited to the case where the contents are filled at a high temperature, and it can be widely applied to products in which a reduced pressure is generated inside the container. In this embodiment, for example, a relatively small synthetic resin container 100 with a content volume of 350 [ml] is assumed, but it is not limited to this aspect. In the present specification, claims, abstract, and drawings, the vertical direction is based on the state where the synthetic resin container 100 is standing upright on a horizontal plane, with the side where the mouth portion 2 is located being the upper side and the side where the bottom portion 5 is located being the lower side. Also, the reference symbol O in Fig. 1 indicates the common central axis of the mouth portion 2, shoulder portion 3, body portion 4, and bottom portion 5 described later. The radially outer side is the direction away from the central axis O along a straight line passing through the central axis O of the synthetic resin container 100 in Fig. 1 and perpendicular to the central axis O, and the radially inner side refers to the direction toward the central axis O along the straight line. Further, the circumferential direction refers to the direction of rotation around the central axis O of the synthetic resin container 100 in Fig. 1. Also, the upper end portion is used to mean the upper edge portion, and the lower end portion is used to mean the lower edge portion.

[0015] The attached drawings of the present disclosure are drawn at the same scale in the vertical, front-rear, and left-right directions, and the aspect ratio of the synthetic resin container 100 on the drawing represents the aspect ratio of the synthetic resin container 100 of an embodiment of the present disclosure. However, the configuration, shape, dimensional ratio, etc. of the synthetic resin container 100 in the attached drawings are only an embodiment of the present disclosure. The present disclosure should be interpreted based on the language of the claims and is not limited to the configuration, shape, dimensional ratio, etc. shown in the drawings.

[0016] This synthetic resin container 100 is formed in a bottle shape having a mouth portion 2 that serves as an outlet for the contents, a shoulder portion 3 that is connected to the lower end of the mouth portion 2 and expands in diameter downward, a body portion 4 that is connected to the mouth portion 2 via the shoulder portion 3 and has a substantially circular shape in plan view, and a bottom portion 5 that closes the lower end of the body portion 4. Note that the shape of the body portion 4 is not limited to a substantially circular shape in plan view, and may be various flat shapes such as an elliptical shape or a truck shape, or a rectangular shape (square container).

[0017] This synthetic resin container 100 can be configured as a so-called PET bottle by biaxially stretching and blow molding a preform made of, for example, polyethylene terephthalate (PET). Note that the synthetic resin container 100 is not limited to polyethylene terephthalate, and may also be formed by biaxially stretching and blow molding a preform made of another synthetic resin having thermoplasticity such as oriented polypropylene (OPP). Further, regarding the manufacturing method of the synthetic resin container 100, not only the method of biaxially stretching and blow molding the preform, but also various manufacturing methods such as extrusion blow molding of a resin material can be adopted.

[0018] On the outer peripheral surface of the mouth portion 2, as shown in FIG. 1, a male screw 2a and a neck ring 2b that extends substantially horizontally outward in the radial direction below the male screw 2a are formed. After the contents are filled at a high temperature, the mouth portion 2 can be closed by screw-engaging a cap (not shown) with the male screw 2a of the mouth portion 2. Further, instead of providing the male screw 2a on the outer peripheral surface of the mouth portion 2, a protrusion may be provided, and the mouth portion 2 may be closed by engaging the cap by caulking.

[0019] The neck ring 2b can be attached to the mold without tilting the preform by bringing the lower surface of the neck ring 2b into contact with the reference surface of the blow mold when molding the synthetic resin container 100 by, for example, stretch blow molding of the preform.

[0020] In this embodiment, the body portion 4 has a substantially circular shape in plan view. As shown in FIG. 1, the body portion 4 is provided with an outer peripheral surface 4a partitioned in the vertical direction by an upper circumferential groove 4b. As shown in FIG. 1, on the outer peripheral surface 4a, six pressure-reducing and absorbing panels 11 having a vertically long shape and recessed radially inward are provided at equal intervals in the circumferential direction. In this embodiment, all six pressure-reducing and absorbing panels 11 are configured in the same shape.

[0021] Also, in this embodiment, the pressure-reducing and absorbing panel 11 is provided at a substantially central height position of the lower outer peripheral surface 4a partitioned by the upper circumferential groove 4b in the body portion 4. Further, the pressure-reducing and absorbing panel 11 is provided with R surfaces that protrude outward from the panel at the four corners in side view (when viewed from the radially outer side), and is configured such that stress concentration is less likely to occur during high-temperature filling and cooling.

[0022] As described above, by providing the upper circumferential groove 4b in the upper portion of the body portion 4, the radial rigidity of the body portion 4 can be increased, and irregular deformation of the container can be suppressed.

[0023] A large bending stress concentrates at the central portion in the vertical direction in a column portion 16 which is a part of the outer peripheral surface 4a of the body portion 4 provided at the circumferential position between the pressure-reducing and absorbing panels 11 shown in FIG. 1 due to internal pressure reduction caused by high-temperature filling or the like. This is because the central position in the vertical direction of the pressure-reducing and absorbing panel 11 is displaced most greatly radially inward, so the central portion in the vertical direction of the column portion 16 is also pulled and bent radially inward. On the other hand, the upper end portion and the lower end portion of the column portion 16 do not have concentrated bending stress because the displacement radially inward of the upper end portion and the lower end portion of the pressure-reducing and absorbing panel 11 is relatively small. For such reasons, a large difference in such bending stress occurs between the central portion in the vertical direction of the column portion 16 and the upper end portion and the lower end portion, so a large stress gradient occurs between the central portion in the vertical direction of the column portion 16 and the upper end portion and the lower end portion. Due to this stress gradient, in a conventional synthetic resin container, the column portion 16 may be bent and plastically deformed at the height position between the central portion in the vertical direction of the column portion 16 and the upper end portion and the lower end portion.

[0024] In this embodiment, in order to suppress the above-described plastic deformation occurring in the column portion 16, column fillets 15 chamfered by a plane are arranged at the left and right edge portions on the upper part of the column portion 16. As shown in FIG. 1, the column fillets 15 extend in the vertical direction from a position closer to the upper side than the central position in the vertical direction of the column portion 16 to the vicinity of the upper end portion of the column portion 16, and are configured such that the chamfering width (circumferential length) is maximized at a position closer to the upper side than the central position in the vertical direction of the column fillets 15. And at the vertical height position where the chamfering width is maximum, the circumferential width of the region of the column portion 16 that overlaps with the outer peripheral surface 4a is about one-third compared to the shape of the two-dot chain line in FIG. 2 where the column fillets 15 are not provided. However, it is not limited to this. The upper end portion of the column fillets 15 extends to the R surfaces at the four corners of the pressure reduction absorption panel 11.

[0025] The column fillets 15 are arranged at vertical positions where the stress gradient is large and plastic deformation is likely to occur when a pressure reduction occurs inside the container. By providing the column fillets 15, the stress in the column portion 16 can be dispersed, so that the column portion 16 becomes easily bendable (easily elastically deformed) in the entire vertical region. Also, by providing the column fillets 15, it is considered that the resilience is improved even when the column portion 16 is broken.

[0026] In this embodiment, the upper end portion of the column portion 16 is a region of the column portion 16 at the same vertical position as the upper end portion of the intersection line between the peripheral wall of the pressure reduction absorption panel 11 (the inclined wall connecting the panel bottom surface and the outer peripheral surface 4a of the body portion 4) and the outer peripheral surface 4a. Similarly, the lower end portion of the column portion 16 is a region of the column portion 16 at the same vertical position as the lower end portion of the intersection line between the peripheral wall of the pressure reduction absorption panel 11 and the outer peripheral surface 4a.

[0027] Also, the vicinity of the upper end portion of the column portion 16 is a region where the vertical distance from the upper end portion of the column portion 16 downward is 10% or less of the vertical length from the upper end portion to the lower end portion of the column portion 16. Similarly, the vicinity of the lower end portion of the column portion 16 is a region where the vertical distance from the lower end portion of the column portion 16 upward is 10% or less of the vertical length from the upper end portion to the lower end portion of the column portion 16.

[0028] As described above, by providing the column fillet 15 at the upper part of the column portion 16, the bending rigidity at the height position where the column fillet 15 is provided in the column portion 16 decreases, so that the stress gradient between the central portion in the vertical direction of the column portion 16 and the upper end portion of the column portion 16 becomes gentle. Therefore, it is possible to effectively suppress the plastic deformation of the column portion 16 at the height position between the central portion in the vertical direction of the column portion 16 and the upper end portion of the column portion 16.

[0029] In addition, in the present embodiment, the column fillet 15 is configured to be provided only at the upper part of the pressure reducing and absorbing panel 11, but is not limited to this aspect. The column fillet 15 may be provided at the lower part of the column portion 16, or may be provided at both the upper and lower parts of the column portion 16.

[0030] When the column fillet 15 is provided at the lower part of the column portion 16, the column fillet 15 preferably extends in the vertical direction from a position closer to the lower side than the central position in the vertical direction of the column portion 16 to the vicinity of the lower end of the column portion 16, and is configured such that the chamfer width is maximized at a position closer to the lower side than the central position in the vertical direction of the column fillet 15. Further, it is preferable that the lower end of the column fillet 15 extends to the R surface at the four corners of the pressure reducing and absorbing panel 11. And, similar to the upper column fillet 15, at the vertical height position where the chamfer width is maximized, the circumferential width of the region of the column portion 16 that overlaps with the outer peripheral surface 4a is about one-third compared to the case where the column fillet 15 is not provided. However, it is not limited thereto.

[0031] In this embodiment, as shown in FIG. 2, the column fillet 15 is configured such that, at the vertical position where the chamfer width is maximum, the circumferential chamfer width WC is longer than the depthwise chamfer width WD of the pressure-reducing and absorbing panel 11. With such a configuration, the thickness of the column part 16 can be reduced over a longer circumferential width of the column part 16, so that the bending rigidity can be easily reduced at the vertical position where the column fillet 15 is provided. Note that WD may be set to be equal to or greater than WC. Also, the width WD is provided to be approximately half of the length of the peripheral wall of the pressure-reducing and absorbing panel 11 (the inclined wall connecting the panel bottom surface and the outer peripheral surface 4a of the body part 4), but the present invention is not limited to this aspect.

[0032] As shown in FIGS. 1 and 2, the basic configuration is that the outer peripheral surface 4a of the body part 4 is left without the column fillet 15 overlapping in the circumferential direction and the column fillet 15 does not reach the panel bottom surface (the peripheral wall is left), but the present invention is not limited to this aspect.

[0033] Also, in this embodiment, although it has been described that the column fillet 15 has a chamfer configuration by a plane, the present invention is not limited to this aspect, and other forms such as an R chamfer may be used as long as the bending rigidity of the column part 16 at the vertical position where the column fillet 15 is provided can be reduced.

[0034] Also, chamfers may be provided at the edge portions on both circumferential sides over the entire vertical range of the column part 16, and the chamfer width may be formed to be large at at least one of the upper and lower portions of the column part 16. In this case, only at least one of the chamfers at the upper and lower portions of the column part 16 where the chamfer width is formed to be large shall be regarded as the "column fillet" of the present disclosure.

[0035] As described above, this embodiment is a synthetic resin container 100 including a mouth portion 2 that serves as an outlet for the contents, a body portion 4 that is connected to the mouth portion 2 via a shoulder portion 3, and a bottom portion 5 that closes the lower end of the body portion 4. The body portion 4 has a plurality of pressure-reducing absorption panels 11 arranged in the circumferential direction and column portions 16 provided at circumferential positions between two adjacent pressure-reducing absorption panels 11 among the plurality of pressure-reducing absorption panels 11. At least one of the upper and lower portions of the column portion 16 is configured to have column portion fillets 15 formed as chamfers on the edges on both circumferential sides of the column portion 16. By adopting such a configuration, the bending rigidity at the height position where the column portion fillets 15 are provided in the column portion 16 decreases, so that the stress gradient between the central portion in the vertical direction of the column portion 16 and at least one of the upper end portion and the lower end portion of the column portion 16 becomes gentle. Therefore, it is possible to effectively suppress the plastic deformation of the column portion 16 at the height position between the central portion in the vertical direction of the column portion 16 and at least one of the upper end portion and the lower end portion of the column portion 16.

[0036] Also, in this embodiment, the column portion fillets 15 extend in the vertical direction from a position closer to the upper side than the central position in the vertical direction of the column portion 16 to the vicinity of the upper end portion of the column portion 16, and the chamfer width is maximized at a position closer to the upper side than the central position in the vertical direction of the column portion fillets 15, or the column portion fillets 15 extend in the vertical direction from a position closer to the lower side than the central position in the vertical direction of the column portion 16 to the vicinity of the lower end portion of the column portion 16, and the chamfer width is maximized at a position closer to the lower side than the central position in the vertical direction of the column portion fillets 15. By adopting such a configuration, it is possible to effectively suppress the stress gradient at a position closer to the upper side than the central position in the vertical direction of the column portion fillets 15 in the upper portion of the column portion 16 or at a position closer to the lower side than the central position in the vertical direction of the column portion fillets 15 in the lower portion of the column portion 16. Therefore, it is possible to lower the bending rigidity of the portion of the column portion 16 where plastic deformation is likely to occur and more effectively suppress the occurrence of plastic deformation.

[0037] Further, in the present embodiment, the column fillet 15 is configured such that, at the vertical position where the chamfer width is maximum, the circumferential chamfer width WC is larger than the depth-direction chamfer width WD of the pressure-reducing absorption panel 11. By adopting such a configuration, the thickness of the column 16 can be reduced over a longer circumferential width of the column 16, so that it is easier to lower the bending rigidity at the vertical position where the column fillet 15 of the column 16 is provided.

[0038] Although the present disclosure has been described based on the drawings and examples, it should be noted that those skilled in the art can easily make various modifications and corrections based on the present disclosure. Therefore, it should be noted that these modifications and corrections are included in the scope of the present invention. For example, the functions included in each component can be rearranged so as not to be logically contradictory, and a plurality of components can be combined into one or divided. It should be understood that these are also included in the scope of the present invention.

[0039] For example, in the present embodiment, the six pressure-reducing absorption panels 11 are configured to have the same shape and the same size, but the present invention is not limited to this aspect, and the pressure-reducing absorption panels 11 may each have a different shape or size. Further, the number of the pressure-reducing absorption panels 11 is not limited to six, and may be five or less or seven or more as long as the required pressure-reducing absorption effect can be obtained.

[0040] Also, in the present embodiment, one upper peripheral groove 4b is provided, but the present invention is not limited to this aspect. A lower peripheral groove may be provided below the pressure-reducing absorption panel 11 in addition to or instead of the upper peripheral groove 4b, or neither may be provided. Further, at least one of the upper peripheral groove 4b and the lower peripheral groove may be provided in a plurality at different height positions.

[0041] Further, the content filled in the synthetic resin container 100 is not limited to beverages such as fruit juice drinks and tea, and seasonings such as soy sauce, vinegar, and sauce, and may be other foods, cosmetics, etc.

Description of Reference Numerals

[0042] 2 Mouth part 2a Male thread 2b Neck ring 3 Shoulder part 4 Barrel part 4a Outer peripheral surface 4b Upper circumferential groove 5 Bottom part 11 Vacuum absorption panel 15 Column part fillet 16 Column part 100 Synthetic resin container O Central axis

Claims

1. A synthetic resin container comprising a mouth portion serving as an outlet for the contents, a body portion connected to the mouth portion via a shoulder portion, and a bottom portion closing the lower end of the body portion, wherein the body portion has a plurality of decompression absorption panels arranged in the circumferential direction and column portions provided at circumferential positions between two adjacent decompression absorption panels among the plurality of decompression absorption panels, and the synthetic resin container has column fillets formed as chamfers at the edges on both circumferential sides of the column portion at at least one of the upper and lower portions of the column portion.

2. The column fillet is provided at the upper portion of the column portion, the column fillet extends in the vertical direction from a position closer to the upper side than the central position in the vertical direction of the column portion to the vicinity of the upper end portion of the column portion, and the width of the chamfer is maximum at a position closer to the upper side than the central position in the vertical direction of the column fillet. The synthetic resin container according to claim 1.

3. The column fillet is provided at the lower portion of the column portion, the column fillet extends in the vertical direction from a position closer to the lower side than the central position in the vertical direction of the column portion to the vicinity of the lower end portion of the column portion, and the width of the chamfer is maximum at a position closer to the lower side than the central position in the vertical direction of the column fillet. The synthetic resin container according to claim 1.

4. The column fillet is a chamfer in which the circumferential chamfer width is larger than the depth-direction chamfer width of the decompression absorption panel at the vertical position where the chamfer width is maximum. The synthetic resin container according to any one of claims 1 to 3.

Images