JP2005112427A - Synthetic resin bottle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a synthetic resin bottle which has a simpler outer appearance and a round shape and is applied to high temperature filling, by forming a body wall shape by which the sufficient vacuum absorbing function of the bottle is fully performed even though the cross-sectional shape of the bottle is substantially circle with fewer recesses and projections. <P>SOLUTION: In the bottle having a body whose cross-section is substantially circle, a pair of panels are formed in the front and back of the body symmetrically relative to the center axis of the bottle such that their perimeters are surrounded by depressed steps. The shape of each panel is such that the cross section has a substantially symmetrical projecting arcuate shape overall and includes a projecting arc with a curvature radius of R1 in the middle and bottom arcs with a curvature radius of R2 which extend right and left via variable curved parts and reach the steps on both the sides. A relation between the curvature radii R1 and R2 and the curvature radii R3 of a pair of side walls of a projecting arcuate shape which are located symmetrically relative to the center axis across the pair of panels is set to R1<R3<R2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a synthetic resin casing, and more particularly to a synthetic resin casing that absorbs deformation of a casing caused by pressure reduction accompanying cooling after filling with a high-temperature content liquid by deformation of a wall.

  Conventionally, there is a so-called high-temperature filling method as a filling method for synthetic resin casings such as polyethylene terephthalate (hereinafter referred to as PET) bottles such as fruit juices and teas that require sterilization. The enclosure is filled with the content liquid at a temperature of, and sealed with a cap, and then cooled, and the inside of the enclosure is considerably decompressed.

  For this reason, for applications involving high-temperature filling as described above, a casing is used in which a vacuum absorbing panel is formed in the body and unauthorized deformation is suppressed by deforming the vacuum absorbing panel. Yes. For example, Patent Document 1 has a description of a housing having this reduced pressure absorption panel, and FIG. 6 shows a housing shown in the embodiment of Patent Document 1.

A casing 101 shown in FIG. 6 is a round bottle having a capacity of 500 ml, and is formed of a mouth tube portion 102, a shoulder portion 103, a trunk portion 104, and a bottom portion 105, and an annular groove portion at a substantially central height position of the casing 1. 106 is formed, and six vacuum absorbing panels 107 are formed below the annular groove 106. The reduced pressure absorption panel 107 has a substantially flat plate shape, and when the inside of the housing 1 is in a reduced pressure state, it can be easily deformed inwardly, so that the appearance is transformed into a distortion. In other words, a function of absorbing (relaxing) the reduced pressure state so as not to stand out (hereinafter referred to as a reduced pressure absorption function) can be exhibited. Further, vertical ribs 108 are formed in the vacuum absorbing panel 107 for the purpose of controlling the deformation of the vacuum absorbing panel 107.
Japanese Patent Laid-Open No. 10-58527

  However, as shown in FIG. 6, the conventional round bottle having a substantially circular cross-sectional shape has a restriction to form a reduced-pressure absorption panel 107 with six or eight reduced-pressure absorption panels 107 from the viewpoint of appearance. The shape is substantially a polyhedron such as a hexahedron or an octahedron. In addition to the vacuum absorbing panel 107, a large number of irregularities such as the annular groove 106 or the vertical rib 108 are formed.

  Especially in a small casing, the required vacuum absorption function is larger, and a vacuum absorption panel is formed over almost the entire area from the trunk to the shoulder of the casing, and the external shape is similar. For example, there is a problem that it does not match the image of a bottle for infants, etc., and there has been a demand for providing a housing having a neat shape with a torso cross section that is close to a circle and has few irregularities.

  Therefore, the present invention was devised to solve the above-described problems in the prior art, and has a trunk wall shape that can exhibit a sufficient decompression absorption function while having a substantially circular cross-sectional shape and a shape with little unevenness. It is an object of the present invention to provide a synthetic resin casing for a high-temperature filling application in a round shape with an unprecedented clean appearance.

The means of the invention according to claim 1 for solving the technical problem is as follows:
The body cross section is a substantially circular enclosure;
Forming a pair of panels surrounding the periphery by a recessed stepped portion at a position symmetrical to the central axis of the housing, before and after the trunk portion;
The shape of the panel is a convex arc shape that is substantially symmetrical in the left-right direction as a whole, and has a convex top arc portion with a radius of curvature R1 at the center and a radius of curvature R2 through the inflection portions on the left and right to reach the step portions on both sides. A shape having a skirt arc,
A configuration in which the magnitude relationship of R3, which is the radius of curvature of the pair of convex arc-shaped side walls located symmetrically with respect to the central axis between the curvature radii R1 and R2 and the pair of panels, is R1 <R3 <R2,
It is in.

  According to the configuration of the above-mentioned claim 1, the body having a substantially circular cross-sectional shape is surrounded by a depressed stepped portion, and a pair of the whole is provided at positions symmetrical with respect to the central axis of the housing. A convex arc-shaped panel is formed, and the shape of the panel is substantially bilaterally symmetric. A convex top arc portion that forms an arc having a radius of curvature R1 located in the center of the left and right, and a radius of curvature located on the left and right thereof is R2. A pair of tail arc portions forming the arc. And the convex top arc part and the tail arc part are connected by the inflection part, and a curvature radius changes gently from R1 to R2 in this inflection part.

  In addition, a pair of arcs having a radius of curvature R1, R2, and R3 in a cross section including a pair of side walls that are symmetrical with respect to the central axis and have a convex arc shape with a radius of curvature R3 between the pair of panels. A cross section of the trunk portion of the casing of the present invention, wherein a pair of convex top arc portions, skirt arc portions and side wall portions forming a pair are arranged opposite to each other at positions symmetrical to the central axis (the skirt arc portions are a total of two pairs). In addition to the stepped portion, the shape can be a smooth curved shape as a whole without any conspicuous unevenness in appearance and without a flat portion.

  Then, by setting the magnitude relationship of the three types of curvature radii R1, R2 and R3 to R1 <R3 <R2, the curvature radius R3 of the side wall portion is substantially equivalent to the radius of the cross-sectional shape of the body portion which is substantially circular. In addition, the panel portion is combined with a convex top arc portion having the smallest radius of curvature (R1) and a tail arc portion having the largest radius of curvature (R2) to form a convex arc shape having an average curvature radius close to R3. The cross-sectional shape of the trunk portion can be substantially circular as a whole.

  In addition, the (R1) convex peak arc portion with the smallest radius of curvature located in the center of the panel exhibits the function of a longitudinal rib, and without conspicuous deformation of the entire panel during decompression, It is possible to absorb the reduced pressure by deforming the bottom arc portion having the largest radius of curvature (R2) inward with the vicinity of the stepped portion at both ends as a fulcrum.

  Further, the convex top arc portion exhibiting the function of a vertical rib can suppress the depression-like deformation of the entire panel even in a high degree of decompression.

  According to a second aspect of the present invention, in the first aspect of the present invention, each of the pair of side wall portions is formed at a central angle of 15 ° to 80 ° (more preferably 30 ° to the central axis of the housing). 70 °).

  If the formation range of the side wall portion is less than 15 °, the strength of the bottle is insufficient, and if it exceeds 80 °, the width of the panel is correspondingly reduced and the reduced pressure absorption function becomes insufficient.

  According to a third aspect of the present invention, in the first or second aspect of the invention, the magnitude relationship between the curvature radii R2 and R3 is 1.2 × R3 ≦ R2 (more preferably 1.5 × R3 ≦ R2). To do.

  When the curvature radius (R2) of the tail arc portion is less than 1.2 times the curvature radius (R3) of the side wall portion, the curvature radius (R2) of the tail arc portion mainly deforming inward during decompression and mainly serving as a decompression absorption function. ) Becomes smaller, it becomes difficult to deform the tail arc portion to the inside of the housing, and the reduced pressure absorption function cannot be fully exhibited.

  According to a fourth aspect of the present invention, in the first, second, or third aspect of the invention, the radius of curvature R1 is 1 mm or more (more preferably 3 mm or more).

  If the radius of curvature (R1) of the convex top arc portion is less than 1 mm, the shape of the vertical rib becomes conspicuous in appearance. Further, the function as the vertical rib is not sufficiently exhibited, and the entire panel is liable to be deformed by depression.

  The means of the invention described in claim 5 is that, in the invention described in claim 1, 2, 3 or 4, the casing is a biaxially stretched blow-molded product made of PET resin.

  By the said structure of Claim 5, the biaxial stretch blow molding housing made from PET resin for the high temperature filling use of the round shape which has the unprecedented shape can be provided.

The present invention has the above-described configuration, and has the following effects.
In the first aspect of the present invention, the panel is formed by combining the convex top arc portion having the smallest radius of curvature (R1) and the tail arc portion having the largest radius of curvature (R2), and the vertical rib is formed on the convex top arc portion. The function of the shape of the body is reduced to the inside of the housing at the bottom arc part, and the vacuum absorption function is demonstrated. A synthetic resin casing for filling applications can be provided.

  In the invention according to claim 2, the strength of the casing is sufficiently exhibited by setting the range of formation of each of the pair of side walls to a range of 15 ° to 80 ° in the central angle with respect to the central axis of the casing. In addition, the panel width sufficient to exhibit the reduced pressure absorption function can be secured.

  In the invention according to claim 3, by making the curvature radius (R2) of the skirt arc portion 1.2 times or more of the curvature radius (R3) of the side wall portion, the skirt arc portion has a sufficient decompression absorption function. It can be demonstrated.

  In the invention according to claim 4, by making the radius of curvature (R1) of the convex apex portion 1 mm or more, the appearance of the vertical rib is not conspicuous in appearance, and the function as the vertical rib is sufficient. It can be demonstrated.

  In invention of Claim 5, the biaxial stretch blow molding housing made from PET resin for the high temperature filling use of the round shape which has the neat shape which was not in the past can be provided.

Embodiments of the present invention will be described below with reference to the drawings.
1 to 5 show an embodiment of the synthetic resin casing of the present invention. This housing 1 is a biaxially stretched blow-molded product made of PET resin, has a mouth tube portion 2, a shoulder portion 3, a body portion 4 and a bottom portion 5, and is a relatively small one having a capacity of about 150 ml. The mouth tube portion 2 is whitened by the thermal crystallization process, and the bottom portion 5 is formed in a depressed shape, and is provided with a bottom rib 6 for improving the strength against deformation.

  In addition, a pair of panels 11 are formed on the front and rear surfaces of the body 4 having a substantially circular cross-sectional shape in a state where the periphery is surrounded by a depressed step portion 12 at a position symmetrical to the central axis.

  FIG. 4 shows a cross-sectional view of the body 4 taken along line AA in FIG. 1, and this cross-sectional shape is substantially along a virtual circle virtually shown by a two-dot chain line in the drawing. Shape. Further, the panel 11 described above is formed in a slightly depressed shape from the virtual circle via the step portion 12.

  Further, the body portion 4 is formed of a pair of panels 11 that are opposed to each other in the front-rear direction and a pair of side wall portions 15 that are located on the left and right sides of the panel portion 11 with a stepped portion 12 therebetween. The arc formed by the side wall 15 overlaps the virtual circle. That is, the radius of the virtual circle and the radius of curvature R3 of the side wall 15 are the same. The width of each side wall 15 is in the range of 60 ° at the central angle α.

  Further, the panel 11 includes a convex top arc portion 13 that is located in the center and forms an arc having a radius of curvature R1, and a tail arc portion 14 that is located on the left and right of the convex top arc portion 13 and that forms an arc having a radius of curvature R2. Have. And the convex top arc part 13 and the bottom arc part 14 are connected so that the boundary may not be conspicuous at the inflection part 16 whose curvature radius changes gently, and the panel 11 as a whole forms a smooth convex arc-like curve. Further, the tip of the convex top arc portion is inscribed in a virtual circle so that the cross-sectional shape of the body portion 4 becomes a shape closer to a circle as a whole.

  FIG. 3 is a view showing the longitudinal sectional shape of the center portion of the panel together with the shoulder portion 3 and a part of the bottom portion 5. However, there is no unevenness except for the step portion 12, and the curved portion including the shoulder portion 3 is smooth. It has a refreshing appearance.

  Further, the curvature radii R1, R2, and R3 of the three kinds of arcs in this embodiment are 15 mm, 50 mm, and 25 mm, respectively, and the magnitude relations thereof are R1 <R3 <R2 and 2 × R3 = R2.

  FIG. 5 shows, as in FIG. 4, the reduced-pressure deformation state in the cross-sectional shape of the body portion 4, together with the shape before deformation (shown by a solid line), by a two-dot chain line. Comparing the deformed state with the shape before deformation, the position of the tip of the convex top arc portion 13 having the radius of curvature R1 is substantially the same as that before the deformation, and the position of the tip of the side wall 15 is slightly expanded, and the largest radius of curvature is obtained. The region mainly composed of the tail arc portion 14 of R2 is deformed inwardly, and the reduced pressure absorption function is exhibited without causing an illegal deformation in appearance.

  In this embodiment, a relatively small biaxial stretch blow-molded PET resin casing of about 150 ml has been described, but the effects of the present invention are the shape, resin, and molding of the casing of this embodiment. The method is not limited to a method or the like, and can be generally applied to a round casing for high-temperature filling applications. Also, the radius of curvature of each arc part, the width of the panel, the height position and height range forming the panel, etc. are the vacuum absorption capacity required for applications such as the filling temperature of the content liquid, the capacity of the housing, and the appearance As a design item considering the above, it can be determined as appropriate.

  It is possible to provide a round synthetic resin casing for a high temperature filling application that has an unprecedented appearance and is expected to be developed in the field of small beverage bottles for infants, for example.

It is a whole front view which shows one Example of the synthetic resin casings of this invention. It is a bottom view of the housing shown in FIG. It is a longitudinal cross-sectional view of the panel center part of the housing shown in FIG. It is a plane sectional view shown along the AA line of FIG. FIG. 5 is a cross-sectional plan view showing a shape deformed under reduced pressure in FIG. It is a whole front view which shows the prior art example of a housing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1; Housing 2; Mouth part 3; Shoulder part 4; Trunk part 5; Bottom part 6; Bottom rib 11; Panel 12; Step part 13; Convex top arc part 14; Part 101; housing 102; mouth tube part 103; shoulder part 104; trunk part 105; bottom part 106; annular groove part 107; decompression absorption panel 108; longitudinal rib R1, R2, R3;

Claims (5)

A body (1) having a substantially circular cross section in the body,
A pair of panels (11) are formed surrounding the periphery by a depressed step portion (12) at positions symmetrical to the center axis of the casing (1), before and after the trunk portion (4), and the panel The shape of (11) has a convex arc shape with a transverse cross section that is substantially bilaterally symmetric as a whole, a convex top arc portion (13) having a radius of curvature R1 in the center, and a step at both ends via a curved portion (16) on the left and right. And a pair of convex arcs located symmetrically about the central axis between the curvature radii R1 and R2 and the pair of panels (11). A synthetic resin casing characterized in that the magnitude relation of R3, which is the radius of curvature of the side wall portion (15), is R1 <R3 <R2. The synthetic resin casing according to claim 1, wherein each of the pair of side wall portions (15) has a formation range of 15 ° to 80 ° in a central angle with respect to the central axis of the casing (1). The synthetic resin casing according to claim 1 or 2, wherein the magnitude relationship between the curvature radii R2 and R3 is 1.2 x R3 ≤ R2. The synthetic resin casing according to claim 1, 2 or 3, wherein the radius of curvature R1 is 1 mm or more. 5. The synthetic resin casing according to claim 1, wherein the casing (1) is a biaxially stretched blow molded product made of polyethylene terephthalate resin.

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