JP2551699Y2 - Carbonated beverage containers - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to one-piece plastic beverage bottles, and more particularly to bottles of the type having a large, flat, horizontal surface that, when filled, hold the bottle in an upright position.

[0002]

A major difficulty with the use of plastic bottles for carbonated beverages is the strength of the bottom of the bottle. 75 psi
Due to internal carbon dioxide pressure in excess of (5.27 kg / cm ² ), plastic bottles have a tendency to bulge outward at the bottom, causing a phenomenon called “rocking” that rocks or tilts back and forth when standing on a flat surface. . In addition, when the bottom bulges outward, the volume of the bottle increases, thereby lowering the filling surface, and consumers will believe that the bottle is not properly filled or sealed.

[0003] One solution to the bulge problem is to mount a bottom cup having a hemispherical bottom and having a flat bottom to support the bottle in an upright position. This type of bottle is commonly referred to as a composite bottle. Complex bottles are widely used in carbonated beverages of 16 ounces (453 g) and higher. However, the increased material cost of the bottom cup has prompted the development of one-piece bottles with free-standing bottoms reinforced to prevent bulging due to carbon dioxide pressure.

When considering the bottom of a bottle, several factors must be considered. Stability is one of the most important factors. The bottle must be stable when empty or full. Empty bottles must be sufficiently stable to stand upright on the bottle filling machine. If the bottle falls over during transport, the efficiency of the filling operation is adversely affected. To obtain a stable bottle, the diameter of the bottle contact area in contact with the horizontal support surface must be maximal. Furthermore, the area of the bottom in surface contact with the support surface must be maximal.

[0005] Another consideration is the strength of the bottom, which resists destruction by impact when the bottle is filled. Bottom stress cracks decrease in strength and make the bottom easier to break. Stress cracking is related to the shape of the bottom. A relatively large radius curve at the bottom reduces stress cracking as compared to a bottom having a smaller radius curve.

Another factor to consider is proper venting of the mold cavity when blowing bottles. Sufficient ventilation ensures that the plastic material is completely blown into each leg at the bottom, forming a foot at the lower end of the leg that defines the bearing surface contact area of the bottle.

[0007]

Problems to be Solved by the Invention Several one-piece bottles have been developed. However, these bottles have some disadvantages associated with their bottom structure. The bottom structure of the plastic bottle deforms downward when filling the bottle with carbonated liquid. When this occurs in some existing plastic bottles, the diameter and size of the bearing surface contact area is reduced, reducing the stability of the bottle when full.

[0008] Some conventional bottles also have a bottom shape with a small foot and a relatively small radius curve. This results in instability of the support and stress cracking, reducing the strength of the bottom and breaking the bottom with impact.

With these shortcomings of the prior art in mind,
SUMMARY OF THE INVENTION It is an object of the present invention to obtain a bottle having a flat support surface contact area which is large in size and diameter compared to the diameter of the bottle, thereby improving the stability of the filled bottle.

Another object of the present invention is to provide a bottle in which the deformation of the bottom by filling does not reduce the contact area of the support surface.

It is another object of the present invention to provide a container having a large radius of curvature and curves which reduces the possibility of stress cracking.

[0012]

SUMMARY OF THE INVENTION The present invention provides an upright longitudinal
Blown plastic material with directional axis
A carbonated beverage container including an upright hollow body made of
The body has a first diameter tubular side wall, the side wall being
At the lower end, a bottom structure is provided.
The structure extends downward from the lower end of the side wall and radially inward.
Lower end in a central portion which is extended and intersects the axis
A curved bottom wall terminating in the middle
The inner and outer ends radially spaced from the core
Numerous defining hollow legs, ending in a nearly flat foot having
The radius of said central part by the wall part projecting downward
The foot is radially outward and the foot is radially
The container on a horizontal support surface.
While holding, the outer end of the foot rests on the horizontal support surface
Are in contact with each other and each foot is approximately
The outer ends of each foot being evenly spaced
Form a discontinuous support surface contact area with a defined outer diameter
The predetermined outer diameter is only slightly smaller than the first diameter.
The inner end of the foot is above the support surface.
Thus, in response to the internal pressure of the carbonated beverage in the container,
The outer diameter of the discontinuous support surface contact area
With the feet held in position, until the feet are almost horizontal
So that it can rotate down around the outer end
In this horizontal position, the inner end
The foot from the lower end to the outer end faces the horizontal support surface
The wall portion extends downwardly from the side wall and
Including the outer leg wall that forms the radially outer surface of the hollow leg
The outer leg wall portion is adjacent to the outer end of the foot
It has a lower end.

[0013] When the container is filled, the diameter of the support surface contact area of the container does not decrease as it is in many prior art containers when the container is filled.
When the container is filled, the outer ends of the feet remain in contact with the horizontal surface, creating the same bearing surface contact area as the empty container.

The wall portion extending downward from the bottom wall is slightly inwardly inclined from the container tubular side wall. This inclination is necessary for the manufacture of the container. By making this slope as small as possible, the radial distance from the container axis to the outer edge of the foot is reduced and a relatively large diameter of the bearing surface contact area is obtained. This improves the stability of the container. In addition, the bottom with a large diameter at the lower end allows the flat surface area of the foot to be larger than indicated in the prior art.

In addition, by increasing the diameter of the bearing surface contact area, the radius of the curve in the bottom can be increased and the stress cracking in the bottom can be reduced.

Further objects, features and advantages of the present invention will become apparent from the following description based on the drawings and the description of the claims for utility model registration.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A prior art plastic container bottom is shown in FIGS. The bottom 102 in FIG. 1 has a number of horizontal feet 104. The outer end of the foot 104, designated by the numeral 105, defines the outer end of the container support surface contact area having a diameter D. The central portion 106 closes the bottom between the inner ends 107 of the feet 104. The central portion 106 projects inwardly into the container and forms a concave outer surface on the wall.

When the container having the bottom 102 is filled with carbonated beverage, the pressure in the container will cause the bottom to deform downward and move the central portion 106 to the position shown by the dashed-dotted line 108. This means that the foot 104 up to the two-dot chain line position 110
Generally rotate about its outer end 105. In this position, the container has a diameter d corresponding to the inner end 110 of the foot.
Supported on a contact surface contact area having The diameter d is much smaller than the diameter D, and the stability of the container when it is filled decreases.

Another prior art container bottom is shown in FIG. Bottom 112 is horizontal foot 114 and foot 114 inner end 1
Extending laterally from 18 to the opposite side of the bottle sidewall, it transitions to the sidewall at point 120. Support surface contact area 1 of bottom 112
22 has a diameter that extends to the outer end 122 of the foot 114 when the container is empty. However, when the container is filled with carbonated beverage, the pressure within the container will curve down the bottom 112 and the previously straight ribs 116 will curve down as shown by dash-dot lines 124. This means that the foot 114
Are rotated about their outer ends 122 generally to the position indicated by. In this position, the diameter of the support surface contact area at the bottom will be slightly
To reduce the stability of filled containers than empty containers.

The plastic container of the present invention has a bottom that does not reduce the contact area of the support surface when the container is filled. A plastic beverage container, indicated generally at 130, having the bottom structure of the present invention is shown in FIG. The container is blow molded from bidirectionally stretched saturated polyester, preferably polyethylene terephthalate (PET), with a flange 134 and a threaded neck 136.
And an integral inclined top 132 having Extending downwardly from the inclined top 132 is a hollow body having a tubular side wall 138. Side wall 138 is generally cylindrical and has an upright longitudinal axis 139 passing through the center. The bottom 140 extends downward from the lower end of the side wall 138 and closes the bottom of the container 130.

The bottom 140 has a downwardly extending bottom wall 142, best shown in FIG. Bottom wall 14
2 is curved inward in the radial direction from the lower end of the tubular side wall 138. As shown in FIG. 5A, the bottom wall 142 is a curve having a constant radius with a radius larger than the radius of the tubular side wall 138. The relatively small radius fillet portion 144 is the bottom wall 1
It is used to move the upper end of 42 to the lower end of the side wall 138. Bottom wall 142 terminates at the lower end of central portion 146 substantially at the center of bottom 140 and crossing axis 139. The central portion is generally horizontal at the bottom center, but may be slightly concave or convex.

The bottom wall defines a hollow leg radially spaced from the central portion 146 and is separated by a number of downwardly projecting wall portions extending below the bottom wall 142. These wall portions, as shown in FIG.
And a leg outer wall portion 150. The leg outer wall portion 150 forms the radially outer surface of the hollow leg. As shown in FIG. 3 and FIG. 5 (a), the leg outer wall portion 150 is a curve having a constant radius curved downward and radially inward. The leg side wall portion 148 extends downward from the bottom wall and radially inward from the leg outer wall portion. The legs terminate in feet 152. FIG. 5 (b) is an enlarged view of the foot portion of FIG. 5 (a). Each foot 1
52 is flat and generally trapezoidal (FIG. 4) having an outer end 154 generally parallel to the inner end 156. Side edge 1 of foot 152
55 inclines radially inward facing each other. The bottom wall is
An inverted V-shaped rib separating the hollow legs is formed in the circumferential direction between the hollow legs.

Each foot 152 defines a flat surface that slopes radially inward and upward, and the outer end 154 of each foot is lower than the inner end of each foot. Outer end 154 of outer leg wall portion 15
0 Fillet part 1 with a relatively small radius adjacent to the lower end
58. The outer end 154 of the foot 152
The diameter of the container 130 is slightly smaller than the diameter of the side wall 138 to form a support surface contact area. By positioning the outer edge of the foot as radially outward as possible, the stability of the bottle is improved.

When the container 130 is filled with the carbonated beverage, the pressure in the container is changed so that the central portion 146 moves to the position indicated by the two-dot chain line 1 in FIG.
It is deformed downward to the position indicated by 60. This central part 1
Due to the downward movement of 46, the foot 152 also moves downward,
The entire rotation about the outer end 154 to a horizontal position indicated by reference numeral 162. In this rotated position, the feet make surface contact with the horizontal surface 163 on which the container is supported. Outer end of contact surface is point 1
54, the diameter of the bearing surface contact area is the central portion 146
Does not decrease as a result of the deformation of Thus, the stability of the bottle does not decrease when the bottle is filled.

The angle 157 at which the feet 152 slope from the horizontal support surface 163 depends on the size of the container and the material thickness at the bottom. These two factors determine the amount of bottom deformation caused by internal pressure. An angle of about 5 ° has been found to be sufficient for containers up to 2 liters and 16 ounces (453 g).

In addition to maintaining bottom stability as the bottom deforms, the surface contact area of foot 162 with surface 163 reduces container vibration. If the collision is not strong enough to collapse, the upright container will oscillate back and forth when impacted. The vibration is eventually dampened and the container is stationary. When the foot 162 is in surface contact with the support surface, the vibration damping is greater when the bottle is empty and supported along the outer edge of the angled foot 152.

Another embodiment of the present invention is illustrated in FIGS. 6 through 10 by a blow molded plastic container generally designated by the reference numeral 10. The container 10 has an integral angled top 13 having a flange 12 and a threaded neck 18. The container 10 also has a hollow tubular side wall 14 and an integral bottom 16. The bottom 16 has a bottom wall extending downward from the side wall 14, as shown in FIG. 10, the bottom wall having an upper portion 20 and a lower portion 30 that curves inward radially downward. The bottom wall is a central portion 2 substantially at the center of the bottom 16.
8

The bottom wall is separated by a number of downwardly projecting wall portions defining a hollow leg 26 extending below the bottom wall. These wall portions have leg side wall portions 32 and leg outer wall portions 33. The leg outer wall portion 33 is a hollow leg portion 26.
Are formed on the outer surface in the radial direction. As shown in FIG.
The leg outer wall portion 33 is uniformly inclined downward and radially inward. The leg ends in a flat foot 25 (FIG. 10) that transitions to a central portion 28. The foot 25 is inclined radially inward and upward, as indicated by the two-dot chain line, indicating the position of the foot when the container is empty. The solid line 27 indicating the foot indicates the position of the foot when the container is filled with carbonated beverage. When the container is filled, the foot 25 rotates generally around its outer end 24 to the position indicated by reference numeral 27 and the foot comes into surface contact with a horizontal surface 29.

Both embodiments of the invention, having the feet as far apart as possible radially outward, allow the feet to have a relatively large flat surface to form a supporting contact surface. The leg outer wall portion slopes or curves downwardly inward to facilitate container removal from the mold. This slope or curvature is made as small as possible, and the discontinuous bearing surface area formed by the outer ends of the feet is slightly smaller than the diameter of the vessel tubular side wall. Moreover, this spacing allows the radius of the bottom curve to be relatively large compared to many prior art techniques, and can reduce or eliminate the possibility of bottom stress cracking. 2 liter bottle and 16 oz (4
53g) 5 feet for both bottles
It has been found that it is best to obtain a large foot at the bottom and a large radius of curvature.

[0030] Containers 10 and 130 are blow molded from injection molded plastic preforms performed in conventional manner. The preform is heated to a temperature at which it can be blow molded and placed in a mold cavity having an inner surface of the required shape for the container. Pressurized air is introduced into the preform, causing the preform to expand outwardly and contact the interior surface of the mold recess. The air in the recess is exhausted through the vent at the bottom of the mold recess, so that the plastic can be completely blown into the foot at the bottom of the mold recess. These vents, in the form of narrow grooves in the mold recess, form small prominent lines on the bottle surface, indicated by line 172 in FIG. 4, line 34 in FIG. 9, and line 36 in FIGS. 6 and 7, respectively. ing.

The hollow legs are formed by blowing the plastic material of the bottom wall downward from the bottom wall. The legs terminate in a generally flat support surface contact area bulging from the bottom wall.
The inclined contact area is rotated by the internal pressure of the container and forms a coplanar area in contact with the horizontal plane supporting the container.

The present invention provides a one-piece blow molded plastic container having a freestanding bottom. The bottom has a bottom wall extending from the lower end of the container side wall. A number of legs extend downward from the bottom wall forming a hollow leg having a flat foot, and the foot slopes upward and inward from the outer end of the leg. When filled with carbonated beverage, the internal pressure of the container pushes the bottom of the bottom down and rotates to a horizontal position, defining a coplanar support surface contact area for supporting the container. This deformation does not result in a decrease in the diameter of the support surface contact area of the container and does not reduce the stability of the container when filled. In addition, the container bottom is formed with a relatively large radius curve, which reduces the amount of stress cracking at the bottom, thereby increasing the strength of the bottom and reducing the possibility of fracture.

The present invention is not limited to the exact structure or method shown and described above, but may be modified and varied without departing from the spirit and scope of the appended claims. Things.

[0034]

The present invention combines the bottom structure with a bottom wall extending downwardly and radially inward from the side walls and a large flat foot extending downwardly from the bottom wall and having radially inward and outward ends. Consisting of legs that terminate, and by making the foot a discontinuous support surface contact area with an outer diameter slightly smaller than the outer diameter, the foot can be stably self-supported both when it is filled and when it is empty. One-piece plastic bottles can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a container bottom according to the related art.

FIG. 2 is a cross-sectional view of a container bottom according to another related art.

FIG. 3 is a side view of the container of the present invention.

FIG. 4 is a bottom view of the container of FIG. 3;

FIG. 5A is a sectional view taken substantially along the line 5-5 in FIG. 4;
(B) is a partially enlarged view of (a).

FIG. 6 is a side view of a variation of the container of the present invention.

FIG. 7 is a side view of a container having a bottom structure different from the bottom structure shown in FIG. 6;

FIG. 8 is a top view of the container of FIGS. 6 and 7.

FIG. 9 is a bottom view of the container of FIGS. 6 and 7;

FIG. 10 is a sectional view taken substantially along the line 10-10 in FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Container 14 Side wall 16 Bottom 25 Feet 26 Legs 33 Leg outer wall 130 Container 140 Bottom 142 Bottom wall 144 Fillet part 146 Center part 148 Leg side wall 150 Outer leg wall part 152 Foot 154 Foot outer end 156 Foot inner end 158 Fillet part

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor George Allen Plummer Two Hundred and Thirty Sixth Street 7015, Graham, Washington, USA 7056 (56) References JP-A-57-194939 (JP, A) (JP, A) JP-A-51-24373 (JP, A) JP-A-61-188905 (JP, U) JP-A-59-196405 (JP, U)

Claims (4)

(57) [Scope of request for utility model registration] 1. A carbonated beverage container comprising an upright hollow body made of blow molded plastic material having an upstanding longitudinal axis, said body having a first diameter tubular sidewall. The side wall merges at its lower end with a bottom structure which extends downwardly and radially inward from the lower end of the side wall and terminates at a lower end in a central portion intersecting the axis. A curved bottom wall, the bottom wall defining a number of downwardly defining hollow legs that terminate in a substantially flat foot having an inner end and an outer end radially spaced from the central portion. Protruding wall portions are separated at a location radially outward of the central portion, and the feet are inclined radially and upwardly while supporting the container on a horizontal support surface. The outer end of the foot is A support surface, wherein each of the feet is substantially evenly spaced from the central portion, and wherein the outer end of each of the feet defines a discontinuous support surface contact area having a predetermined outer diameter. And the predetermined outer diameter is the first diameter.
Only slightly smaller than the diameter, the inner end of the foot is above the support surface, so that in response to the internal pressure of the carbonated beverage in the container, the outer end of the discontinuous support surface contact area With the diameter maintained substantially constant, the foot can rotate downwardly around the outer end until the foot is in a substantially horizontal position, in which position the foot is substantially free of the inner end. To the outer end are in face-to-face contact with the horizontal support surface, and the bottom wall further comprises:
At the center of the bottom structure is a substantially horizontal central portion,
The central part is radially outward and below the center of the bottom structure
Extending outwardly and transitioning to the inner end of the foot, the wall portion includes an outer leg wall portion extending downwardly from the side wall to form a radially outer surface of the hollow leg. A carbonated beverage container, wherein the portion has a lower end adjacent the outer end of the foot. 2. The carbonated beverage container according to claim 1, wherein the outer leg wall portion is connected to the outer end of the foot by a curved wall portion. 3. The carbonated beverage container according to claim 1, wherein each outer leg wall portion tapers radially inward as the outer leg wall portion extends downward from the side wall. A carbonated beverage container comprising a portion. 4. The carbonated beverage container according to claim 1, wherein said outer leg wall portion includes a substantially constant radius arcuate wall portion bent radially inward downward from said side wall. Beverage container.