Containers with pressure-adaptive bases

Abstract

A container includes: a body defining an interior volume configured to contain a fluid, the body having an axis; a base at a lower end of the body, the base including: an outer ring at a lower end of the base, the outer ring defining a plane of support for the container; a transitional wall extending from the outer ring to a first height above the outer ring within the interior volume; an adaptive ring extending from the transitional wall to an inner edge and movable, in the presence of a vacuum, from a first position with the inner edge at a second height smaller than the first height, to a second position with the inner edge at a third height greater than the first height; and a push-up centered on the axis and coupled to the inner edge of the adaptive ring.

Description

CONTAINERS WITH PRESSURE-ADAPTIVE BASESCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority from U.S. provisional patent application no. 63 / 581038, filed September 7, 2023, the contents of which is incorporated herein by reference.FIELD

[0002] The present invention relates to containers for fluids, and more particularly to containers with pressure-adaptive bases.BACKGROUND

[0003] Containers such as plastic bottles (e.g., polyethylene terephthalate or PET) are used for packaging various fluid, including beverages such as water, juice, carbonated soft drinks, and the like. Filling such containers can be achieved with various processes, including hot-filling, which involves dispensing fluid into bottles (e.g., on a conveyor or other transport device) at a relatively high temperature (e.g., 65 to 100 degrees C) and capping or otherwise closing the containers. As the fluid cools to a storage temperature (e.g., between about 4 degrees C to about 25 degrees C, depending on the fluid), the fluid’s density may increase, and the resulting reduction in volume of the fluid can generate a vacuum within the container.

[0004] In other cases, the containers may be filled with carbonated fluids that exert positive pressure within the containers once filled. To mitigate deformation of the containers resulting from a vacuum, some containers may be provided with reinforcing structures on the side walls thereof, such as thicker wall panels, reinforcing ribs on the side walls, or the like. Other containers may be provided with reinforced bases, e.g., based on a petalized design, to resist deformation from positive pressure within the container. The above reinforcing structures may increase the cost and / or complexity of manufacturing the containers.SUMMARY

[0005] Examples disclosed herein are directed to a container including: a body defining an interior volume configured to contain a fluid, the body having an axis; a base at a lower end of the body, the base including: an outer ring at a lower end of the base, the outer ring defining a plane of support for the container; a transitional wall extending from the outer ring to a first height above the outer ring within the interior volume; an adaptive ring extending from the transitional wall to an inner edge and movable, in the presence of a vacuum, from a first position with the inner edge at a second height smaller than the first height, to a second position with the inner edge at a third height greater than the first height; and a push-up centered on the axis and coupled to the inner edge of the adaptive ring.BRIEF DESCRIPTIONS OF THE DRAWINGS

[0006] Embodiments are described with reference to the following figures.

[0007] FIG. 1 is a diagram of a container.

[0008] FIG. 2A illustrates a partial cross-section of the container of FIG. 1 , taken at the plane S2.

[0009] FIG. 2B illustrates a perspective view of the partial cross section of FIG. 2A.

[0010] FIG. 3A illustrates the partial cross-section of FIG. 2A, in the presence of a vacuum within the container.

[0011] FIG. 3B illustrates a perspective view of the partial cross section of FIG. 3A.

[0012] FIG. 4A illustrates a partial cross-section of the container of FIG. 1 according to another example, taken at the plane S2.

[0013] FIG. 4B illustrates the partial cross-section of FIG. 4A, in the presence of positive pressure within the container.DETAILED DESCRIPTION

[0014] FIG. 1 illustrates a container 100 for holding fluids, such as water, juice, carbonated soft drinks, or the like. The container 100 is a plastic (e.g., PET) bottle manufactured in a single piece by blow molding, in this example, but may also be fabricated from other suitable materials. The container 100 includes a body 104, e.g.,including a substantially cylindrical side wall and defining an interior volume 108 for containing fluid. The container 100 includes a shoulder 112 extending from an upper end of the body 104, and defining a further portion of the interior volume 108. At least a portion 114 of the body 104 includes a continuous cylindrical surface, e.g., unbroken by reinforcing panels, vertical ribs, or the like. In some examples, the body 104 can include substantially annular ridges, e.g. the two shown in FIG. 1 , and can be smoothwalled at least between those ridges.

[0015] The container 100 further includes a neck 116 extending from an upper end of the shoulder 112, and defining an opening 120 into the interior volume (which may be capped or otherwise sealed). The container 100 also includes a heel 124 defining a transition from the substantially vertical (e.g., substantially parallel to an axis 128 of the container 100) side wall(s) of the body 104 to a plane of support defined by a base 132 of the container 100. The plane of support permits the container 100 to rest on a surface, e.g., a substantially horizontal surface.

[0016] As seen above, various terms are used to describe the position and / or orientation of some components of the container 100, e.g., relative to other components. Terms such as upper, above, or the like, indicate a position closer to the opening 120 than the base 132, while terms such as lower, below, or the like indicate a position closer to the base 132 than the opening 120. Terms such as outer, outwards, or the like, indicate a position further from the axis 128, while terms such as inner, inwards, or the like, indicate a position closer to the axis 128. Terms such as vertical indicate an orientation substantially parallel to the axis 128, while terms such as horizontal indicate an orientation substantially perpendicular to the axis 128.

[0017] As described below, the base 132 includes various structural features enabling the base 132 to deform in a controlled manner in response to negative pressure (e.g., below 760 mm Hg) within the interior volume 108. As will be apparent, a vacuum may result in the interior volume 108 when the container 100 is hot-filled, e.g., with fluid being dispensed into the container 100 at a temperature above about 65 degrees C. As the fluid cools, its density may increase and its volume may therefore shrink. Because the container 100 is generally capped or otherwise sealed before the fluid has cooled, the reduction in volume of the fluid generates a vacuum within the interior volume 108. In some bottles, negative pressure in the interior volume 108 can lead to deformation and / or collapse of the side walls of the body 104. The structuralfeatures of the base 132 mitigate such deformation, by permitting the base 132 itself to deform at lower vacuum levels than the body 104, and thus reduce the vacuum level in the interior volume 108 by shrinking the interior volume 108.

[0018] FIG. 2A and FIG. 2B illustrate a partial cross-section of the container 100, taken at the plane S2 labelled in FIG. 1. The base 132 includes an outer ring 200 at a lower end of the base 132. The outer ring 200 defines a plane of support for the container 100, e.g., permitting the container 100 to rest on a support surface. The outer ring 200, in other words, contacts the support surface when the container is placed upright in normal use.

[0019] The base 132 further includes a transitional wall 204 extending from the outer ring 204 to a first height 208 above the outer ring 132 and within the interior volume 102. The wall 204, in this example, is within about 20 degrees of being parallel with the axis 128 (e.g., is closer to vertical than to horizontal). The base 132 further includes an adaptive ring 212 extending from the transitional wall to an inner edge 216 of the adaptive ring 212. The adaptive ring 212 is movable, in the presence of a vacuum within the interior volume 102, from a first position (shown in FIG. 2A) to a second position shown in FIG. 3A. In the first position, the inner edge 216 is at a second height 220 smaller than the first height 208. In other words, in the first position, the adaptive ring 212 is angled downwards as it extends towards the axis 128 from the transitional wall 204. The angle 222 of the adaptive wall 212 in the first position, as shown in the detailed view 224, is between about 2 and about 15 degrees in this example, relative to horizontal. Angling the adaptive wall 212 enables the adaptive wall 212 to have a greater surface area relative to a horizontal ring, and thus a greater exposure to internal pressure in the container 100.

[0020] In some examples, the adaptive ring 212 can include a reinforcing ring 228, which may also be referred to as a pinching ring or an active rib, to increase the stiffness of the adaptive ring 212. The reinforcing ring 228 can extend upwards from the adaptive ring, e.g., in the form of an embossed portion of the ring 212. In other examples, the reinforcing ring 228 can extend downwards from the adaptive ring 212. In further examples, the reinforcing ring 228 can include a thickened portion of the adaptive ring 212, e.g., with outer surfaces extending either or both of upwards and downwards from the plane containing the remainder of the adaptive ring 212.

[0021] The reinforcing ring 228 can be positioned, for example, at least half way from the transitional wall 204 towards the inner edge 216. That is, for a length 232 of the adaptive ring 212 (the “length” illustrated in FIG. 2A being a difference between the inner and outer radii of the adaptive ring 212), an outer edge of the reinforcing ring 228 can be located at a radial distance 236 from the transitional wall 204 (that is, a distance 236 towards the axis 128). In some examples, the reinforcing ring can be positioned about two thirds of the way towards the axis 128, from the transitional wall 204.

[0022] The reinforcing ring 228 acts to prevent localized deformation of the adaptive ring 212, e.g., as the adaptive ring 212 moves between the first and second positions in response to vacuum forces. For example, the reinforcing ring 228 may ensure that each portion of the adaptive ring 212 moves upwards or downwards in concert with the remainder of the adaptive ring 212.

[0023] The container 100 further includes a push-up or central cup 240, centered on the axis 128 and extending upwards into the interior volume from the inner edge 216 of the adaptive wall 212. The push-up 240 has the shape of a truncated cone in this example, e.g., with a top surface 244 having a smaller diameter than the inner edge 216. In some examples, the top surface 244 can be convex as seen from below the container 100. That is, the top surface 244 can be angled upwards, towards the axis 128, at an angle of between zero and three degrees.

[0024] As will be apparent from the discussion above, the position of the push-up 240 within the interior volume is determined by the position of the adaptive ring 212. When the container 100 is at rest (e.g., the interior pressure matches ambient pressure), the adaptive ring 212 and the push-up 240 are in the position shown in FIGS. 2A and 2B. The inner edger 216, which is generally the lowest point (e.g., closest to the outer edge 200) of the adaptive ring 212 and the push-up 240, is maintained at a minimum distance 248 above the plane containing the outer ring 200. The distance 248 can be, for example, about 40% of the length 232, although other ratios between the length 232 and the height 248 are also contemplated.

[0025] Referring to FIG. 3A and FIG. 3B, the base 132 is shown in the second position mentioned earlier, in which the inner edge 216 (and thus the lowest portion of the push-up 240) is at a third height 300 relative to the outer edge 200. The third height300 is greater than the first heigh 208 (and therefore also greater than the second height 220). The base 132, and in particular the adaptive wall 212, moves to the position shown in FIG. 3A in response to a vacuum in the interior volume 102. Under the effect of the vacuum, the adaptive wall 212 is drawn upwards, tilting about the annular joint between the transitional wall 204 and the adaptive wall 212. The inner edge 216 therefore rises into the interior volume 102, and the push-up 240 also rises. A side wall 304 of the push-up 240 may expand in some examples to accommodate the increased inner radius 308 of the inner edge 216 (relative to the inner radius of the inner edge 216 in the first position shown in FIG. 2A).

[0026] As will be apparent, when the adaptive wall 212 and the push-up 240 rise into the interior volume 102, the interior volume 102 shrinks, thus reducing the effect of any negative pressure in the interior volume 102. The adaptive wall 212 and pushup 240 are configured to transition to the second position shown in FIG. 3A in response to a vacuum level smaller than a level that would result in deformation of the side walls of the body 104.

[0027] FIG. 4A and FIG. 4B illustrate another example base 132a, used to accommodate positive pressure within the interior volume 102 (e.g., hydrostatic pressure, pressure generated by carbonate fluids in the container 102, or the like). The base 132a may enable the container 100 to avoid deformation of the side walls of the body 104 under positive pressure, while mitigating the need for base structures such as a petal base, which generally require a greater mass of material than does the base 132a.

[0028] The base 132a includes a push-up 240 with an upper surface 244 as described above. The base 132a further includes a transitional wall 204a, an adaptive ring 212a, and a reinforcing ring 228a, e.g., disposed at one end of the adaptive wall 212a. Under positive internal pressure, the adaptive ring 212a tilts as shown in FIG. 4B to transition the inner edge 216a from the first position of FIG. 4A (at a first height 400 from the outer edge 200) to the second position of FIG. 4B (at a second, smaller height 404 from the outer edge 200), increasing the interior volume 102 and absorbing at least a portion of the internal pressure.

[0029] The scope of the claims should not be limited by the embodiments set forth in the above examples, but should be given the broadest interpretation consistent with the description as a whole.

Claims

CLAIMS1. A container, comprising: a body defining an interior volume configured to contain a fluid, the body having an axis; a base at a lower end of the body, the base including: an outer ring at a lower end of the base, the outer ring defining a plane of support for the container; a transitional wall extending from the outer ring to a first height above the outer ring within the interior volume; an adaptive ring extending from the transitional wall to an inner edge and movable, in the presence of a vacuum, from a first position with the inner edge at a second height smaller than the first height, to a second position with the inner edge at a third height greater than the first height; and a push-up centered on the axis and coupled to the inner edge of the adaptive ring.

2. The container of claim 1 , further comprising: a shoulder at an upper end of the body, the shoulder further defining the interior volume; and a neck at an upper end of the shoulder, defining an opening into the interior volume.

3. The container of claim 1 , wherein the body includes a continuous cylindrical side wall.

4. The container of claim 1 , wherein in the first position, the adaptive ring has an angle of between 2 and 15 degrees relative to the plane of support defined by the outer ring.

5. The container of claim 1 , wherein the adaptive ring includes a reinforcing ring.

6. The container of claim 5, wherein the reinforcing ring is disposed at least half way from the transitional wall to the inner edge.

7. The container of claim 6, wherein the reinforcing ring is disposed at least two thirds of the way from the transitional wall to the inner edge.

8. The container of claim 5, wherein the reinforcing ring extends upwards from the adaptive ring.

9. The container of claim 1 , wherein in response to the vacuum, the adaptive wall tilts about a joint between the transitional wall and the adaptive wall, from the first position to the second position.

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