JP4697630B2 - Blow molding bottle - Google Patents

Description

  The present invention relates to a biaxial stretch blow molded synthetic resin bottle, and more particularly to a blow molded bottle that is large in size and has a flat body portion that heat-fills a content liquid.

  Of the large synthetic resin biaxially stretched blow molded bottles, the body has a flat cross-sectional shape such as an oval or a rectangle. In order to prevent the occurrence of bottom-down due to heat, the bottom wall of the bottom part is formed with a large spherical arc shell-shaped recessed wall part at the center, and a plurality of reinforcing ribs are provided radially on the recessed wall part, It is set as the structure which provided the ground-wall part in the circumference | surroundings.

In the configuration of this prior art, since a large portion of the bottom wall is configured by the recessed wall portion reinforced with the reinforcing rib, it is possible to strongly prevent the occurrence of bottom-down due to heat.
Japanese Patent Laid-Open No. 08-026239

  However, in the above-described prior art, since the end portion of the reinforcing rib is located directly between the extension center portions of the recessed wall portion, the moldability of the recessed wall portion including the reinforcing rib is not always good. However, there is a problem that molding defects may occur.

  In addition, the grounding wall portion formed around the spherical arc-shaped depressed wall portion is naturally a circular ring shape, but since the flat cross-sectional shape of the trunk portion is flat, According to the flat shape, the ring width on the short diameter side must be reduced, and therefore, the grounding wall portion on the short diameter direction, which is originally inferior to the stability of the “sitting” compared to the long diameter direction, exhibits. There was a problem that the function of the “seat” of the bottle became unstable.

  Therefore, the present invention was devised to solve the above-mentioned problems in the prior art, and forms a reinforcing rib in the stretched portion of the bottom wall and the ring width of the ground wall portion on the short diameter direction side. It is an object of the present invention to satisfactorily secure the bottom wall having a plurality of reinforcing ribs and to provide a stable “seat” function.

Among the present invention for solving the above technical problems, the means of the invention according to claim 1 is:
A biaxial stretch blow molded bottle made of a synthetic resin having a flat barrel,
The bottom wall of the bottom that is connected to the lower end of the torso, a substantially elliptical ring-shaped grounding wall that forms the peripheral edge, and a central spherical arc that is recessed inside the grounding wall. A dome skirt having a dome wall portion having a dome flared portion extending continuously from a lower end periphery of a shell-shaped dome main portion, and a dome hem of a long diameter region located at least on a long diameter direction side of the dome wall portion A plurality of reinforcing ribs extending along the radial direction are provided at intervals in the portion extending from the entire width range of the portion and the peripheral end portion of the dome main portion, and the reinforcing ribs of both long diameter regions are arranged symmetrically. thing,
Increasing the ring width along the minor axis direction of the ground wall,
It is in.

  In the first aspect of the present invention, since the reinforcing rib is provided at the dome skirt having a gentle slope at least in the long-diameter region, the dome skirt is strongly reinforced. Make sure to prevent bottoming out.

  In addition, since the extension center portion is located at the center portion of the dome main portion of the bottom wall, and the dome skirt located around the dome main portion is an extension deformation portion, The reinforcing ribs formed in the portion extending from the peripheral end of the dome main part are formed without difficulty.

  Furthermore, since the dome hem is not a spherical arc but a portion that is simply inclined to spread out, the width of the dome is not restricted uniformly. By setting according to the ring shape, the width of the ground wall along the minor axis direction can be set to a desired value.

  According to a second aspect of the present invention, in the configuration of the first aspect of the invention, a step is provided in which the dome wall portion is recessed between the ground wall portion and the peripheral end portion constituting the continuous portion with the ground wall portion. In addition to the fact that a skirt step portion having a substantially elliptical ring shape is formed.

  In the second aspect of the present invention, since the stepped portion is formed in the connecting portion between the grounding wall portion and the depressed dome wall portion, the dome wall portion is formed by the action of internal pressure or the like. Even if a slight downward displacement occurs, a part of the dome wall portion does not come into contact with the placement surface of the bottle.

  In the invention according to claim 3, in the configuration of the invention according to claim 1 or 2, an auxiliary rib having a protruding height and a width smaller than that of the reinforcing rib is provided between the reinforcing ribs provided in the long diameter region. , Plus.

  In the third aspect of the invention, in order to obtain the same reinforcing strength, by providing auxiliary ribs that can be easily molded, the number of reinforcing ribs can be sufficiently reduced and the number thereof can be reduced.

  The invention described in claim 4 adds to the configuration of the invention described in claim 1, 2 or 3 that the trunk portion has a rectangular cylindrical structure in which four corners are chamfered by substantially flat corner walls. It is a thing.

  In this invention of Claim 4, the outstanding "seat" function can be provided to the rectangular square bottle produced in large numbers as a large sized biaxial stretch blow molding bottle.

Since the present invention has the above-described configuration, the following effects can be obtained.
In the first aspect of the present invention, the dome skirt portion, which has a gentle slope and does not necessarily have sufficient internal pressure resistance, is strongly reinforced by the reinforcing ribs, so that it is possible to reliably prevent the dome wall from falling down. Since the reinforcing ribs can be formed without difficulty and stably, it is possible to obtain high productivity of bottles without bottoming out, and more stable “seat” function. The handling condition in liquid filling or the like becomes good.

  In the invention according to claim 2, since a part of the dome wall portion does not come into contact with the placement surface of the bottle, the grounding wall portion always exhibits a stable "seat" function.

  In the invention described in claim 3, the reinforcing rib can be stably and satisfactorily molded without lowering the reinforcing strength by the rib, and thereby high quality can be obtained.

  In the invention described in claim 4, since the standing posture of the rectangular square bottles produced in large numbers as the large biaxial stretch blow molded bottles becomes stable, stable handling can be obtained.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  The bottle according to the present invention (refer to FIG. 1 hereinafter) has a barrel 3 in the shape of a rectangular cylinder and a thread on the outer peripheral surface of the upper end of the barrel 3 via a shoulder 2 having a substantially truncated pyramid shape. And a neck portion provided in a cylindrical shape, and a bottom portion 8 connected to the lower end of the body portion 3.

  The body portion 3 is formed by rounding four corners with a substantially flat corner wall 5 having a small width, and is formed into a rectangular cylindrical shape with the four flat walls 4. A circumferential groove 7 is provided over the entire circumference.

  The flat wall 4 has a wide portion that forms the front surface and the back surface, and a narrow portion that forms both side surfaces, and each flat wall 4 portion divided vertically by the circumferential groove 7 absorbs reduced pressure. A panel wall portion 6 is formed.

  A bottom portion 8 (refer to FIG. 2 hereinafter) connected to the lower end of the body portion 3 is connected to the lower end edge of the body portion 3 and has a bottom peripheral wall 9 that is curved and contracted downward, and a lower end of the bottom peripheral wall 9. The bottom wall 10 is connected to the bottom wall 10 and closes the lower portion of the body 3, and the bottom wall 10 is positioned inside the ground wall 11 and a ground wall 11 that forms a peripheral end portion. The dome wall 12 is recessed inward.

  The grounding wall portion 11 is matched with the flat cross-sectional shape of the body portion 3 so that the long side direction of the body portion 3 is the long diameter direction, and the short side direction of the body portion 3 is the short diameter direction. The ring width along the minor axis direction is sufficiently large.

  The dome wall portion 12 that is recessed and continuously provided inside the ground wall portion 11 forms a continuous portion with the ground wall portion 11, and a recessed step (see FIG. 4) between the ground wall portion 11. A dome main portion 15 formed into a spherical arc shell shape in a form in which a substantially elliptical ring-shaped skirt step portion 13 and an upper end central portion where an extension center portion is located are curved and protruded downward, The dome main portion 15 and the skirt step portion 13 are constituted by a dome skirt portion 14 that is connected in an upwardly inclined manner.

  The dome wall portion 12 is roughly divided into two major axis regions D located on the major axis direction side and two minor axis regions d located on the minor axis side side (see FIG. 2). As shown in FIG. 2, the inclination angle of the dome skirt 14 in the short diameter region d is abrupt, as is clear from the irregular cross-sectional view taken along the line AA in FIG. The inclination angle of the dome skirt 14 at D is gentle.

Three reinforcing ribs 16 having large projecting dimensions and width dimensions are provided on the dome skirt part 14 in the long diameter region D where the inclination angle becomes gentle, with a sufficient space between the outer peripheral edge of the dome skirt part ( 3) (see FIG. 4 which is an enlarged view of a portion surrounded by a circle a in FIG. 3) to the peripheral end of the dome main portion 15, and is provided along the radial direction. ,
An auxiliary rib 17 is provided.

  The reinforcing rib 16 and the auxiliary rib 17 have the cross-sectional structure shown in FIG. 5 which is an irregular cross-sectional view taken along the line BB in FIG. Compared to the rib 16, the projecting dimension and the width dimension are small, and the moldability is improved accordingly, so that the auxiliary rib 17 is provided between the reinforcing ribs 16 so that the moldability is not deteriorated.

  Further, the reinforcing ribs 16 can maintain good moldability by increasing the interval, while the auxiliary ribs 17 have a long diameter region due to the increase in the interval between the reinforcing ribs 16. The variation in the reinforcing force with respect to the dome skirt portion 14 of D is made as small as possible.

  In the above description, the reinforcing ribs 16 and the auxiliary ribs 17 are shown in the configuration example provided in the dome skirt 14 portion of the long diameter region D. However, depending on the case, the reinforcing ribs 16 and the auxiliary ribs 17 are provided. May also be provided in the dome skirt 14 portion of the short diameter region d.

1 is an overall front view showing an embodiment of the present invention. It is an enlarged bottom view of the bottle shown in FIG. FIG. 3 is an irregular partial longitudinal sectional view taken along the line AA in FIG. FIG. 4 is an enlarged view of a portion surrounded by a circle in FIG. 3. FIG. 3 is an irregular partial longitudinal sectional view taken along the line B-B in FIG. 2.

Explanation of symbols

1; Mouth part 2; Shoulder part 3; Body part 4; Flat wall 5; Corner wall 6; Panel wall part 7; Circumferential groove 8; Bottom part 9; Bottom peripheral wall 10; Part 13; skirt step part 14; dome skirt part 15; dome main part 16; reinforcing rib 17; auxiliary rib D; major axis area d;

Claims (4)

A synthetic resin biaxially stretched blow-molded bottle having a flat barrel (3), wherein the bottom wall (10) of the bottom (8) connected to the lower end of the barrel (3) A substantially elliptical ring-shaped grounding wall portion (11) that forms a rim, and a lower peripheral edge of a central spherical arc-shell-shaped dome main portion (15) that is recessed and connected to the inside of the grounding wall portion (11) And a dome wall portion (12) continuously provided with a dome-shaped hem portion (14) having a hem-opening shape, and a long diameter region (D) portion located at least on the long diameter direction side of the dome wall portion (12). A plurality of reinforcing ribs (16) extending along the radial direction are provided at intervals in the entire width range of the dome skirt (14) and the peripheral end of the dome main portion (15). diameter area (D) a partial reinforcing rib (16) constructed by arranging symmetrically, Li along the minor axis direction of the ground wall (11) Blow molded bottles, characterized in that increasing the grayed width.   A substantially elliptical ring that forms a depressed step portion between the dome wall portion (12) and the ground wall portion (11) at a peripheral end portion that forms a continuous portion with the ground wall portion (11). The blow-molded bottle according to claim 1, wherein a shaped skirt step (13) is formed.   The blow according to claim 1 or 2, wherein auxiliary ribs (17) having a protruding height and a width smaller than those of the reinforcing ribs (16) are provided between the reinforcing ribs (16) provided in the long diameter region (D). Molded bottle.   The blow-molded bottle according to claim 1, 2 or 3, wherein the body (3) has a rectangular cylindrical structure with four corners chamfered by substantially flat corner walls (5).

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