Preform design for lightweight container

Abstract

A preform configured to form a container by stretch blow molding. A finish portion is at a first end of the preform, and is a container finish. A tip portion is at a second end of the preform opposite to the first end, and is configured to form a container base and a container heel. The shoulder portion is adjacent to the finish portion and is between the finish portion and the tip portion. The shoulder portion is configured to form a container shoulder. The body portion is between the shoulder portion and the tip portion, and is configured to form a container body. The outer surface includes a first flat portion and a second flat portion at the tip portion. The first flat portion extends at a first angle and the second flat portion extends at a second angle that is different than the first angle.

Claims

1. A preform configured to form a container by stretch blow molding, the preform comprising: a finish portion at a first end of the preform, the finish portion is a container finish of the container; a tip portion at a second end of the preform opposite to the first end, the tip portion configured to form a container base and a container heel of the container; a shoulder portion adjacent to the finish portion and between the finish portion and the tip portion, the shoulder portion configured to form a container shoulder of the container; a body portion between the shoulder portion and the tip portion, the body portion configured to form a container body of the container; an outer surface including a first flat portion and a second flat portion at the tip portion, the first flat portion extends at a first angle relative to a longitudinal axis of the preform, and the second flat portion extends at a second angle relative to the longitudinal axis of the preform, the second angle is different than the first angle; and an inner surface opposite to the outer surface, the inner surface includes a first radius opposite to the first flat portion and a second radius opposite to the second flat portion, the first radius is larger than the second radius.

2. The preform of claim 1, wherein the outer surface includes a curved portion between the first flat portion and the second flat portion.

3. The preform of claim 1, wherein the curved portion is directly adjacent to the first flat portion and the second flat portion.

4. The preform of claim 1, wherein the preform is injection molded.

5. The preform of claim 1, wherein the preform is configured to form the container such that the container includes less than one gram of container material per ounce of container capacity.

6. The preform of claim 1, wherein the preform is configured to form the container such that the container heel includes a first material band and the container base includes a second material band, the first material band is a heaviest material band of the container, and the second material band is a lightest material band of the container.

7. The preform of claim 1, wherein the preform is configured to form the container with a thickness of about 0.010 inches at the container body.

8. The preform of claim 1, wherein the preform is configured to form the container with a thickness of about 0.010 inches at the container heel.

9. The preform of claim 1, wherein the preform is configured to form the container such that the container is thinnest at the container base.

10. The preform of claim 1, wherein the preform is configured to form the container with a thickness of about 0.008 inches at the container base.

11. The preform of claim 1, wherein the tip portion is thickest adjacent to the body portion.

12. The preform of claim 1, wherein the first flat portion and the second flat portion have the same length.

13. The preform of claim 1, wherein the first flat portion is adjacent to the body portion, and the first angle is less than the second angle.

14. The preform of claim 1, the preform further comprising an inner surface opposite to the outer surface, at the tip portion the inner surface is 14% shorter than the outer surface.

15. The preform of claim 1, the preform further comprising an inner surface opposite to the outer surface, the inner surface is 6% shorter than the outer surface.

16. The preform of claim 1, wherein the preform includes a total inner surface area that is 72% of a total outer surface area.

17. The preform of claim 1, wherein the shoulder portion includes: a shoulder height that is 28% of a total height of the preform; a shoulder weight that is 28% of a total weight of the preform; and a shoulder volume that is 31% of a total volume of the preform.

18. The preform of claim 1, wherein the body portion includes: a body height that is about 42% of a total height of the preform; a body weight that is about 45% of a total weight of the preform; and a body volume that is about 43% of a total volume of the preform.

19. The preform of claim 1, wherein the tip portion includes: a tip height that is about 30% of a total height of the preform; a tip weight that is about 27% of a total weight of the preform; and a tip volume that is about 26% of a total volume of the preform.

20. The preform of claim 1, wherein the preform is configured to form the container such that the container is thickest at the container shoulder.

21. The preform of claim 20, wherein the preform is configured to form the container with a thickness of about 0.012 inches at the shoulder.

22. The preform of claim 20, wherein the container shoulder is thickest at the container finish.

Description

DRAWINGS

(1) The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

(2) FIG. 1 is a cross-sectional view of a preform according to the present teachings, and a container according to the present teachings formed by stretch blow molding the preform;

(3) FIG. 2A is a cross-sectional view of one-half of the preform of FIG. 1 and one-half of the container of FIG. 1, portions of the preform are projected onto the container to illustrate the different portions of the container formed by different portions of the preform;

(4) FIG. 2B is a chart of various exemplary dimensions for sections of the preform;

(5) FIG. 3A is a cross-sectional view of the preform of FIG. 1; and

(6) FIG. 3B is a close up view of one-half of a base/heel portion of the preform in cross-section.

(7) Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION

(8) Example embodiments will now be described more fully with reference to the accompanying drawings.

(9) With initial reference to FIG. 1, a preform according to the present teachings is generally illustrated at reference numeral 110. The preform 110 can be made of any suitable material. Any suitable polymeric material can be used, such as polyethylene terephthalate (PET) for example. The preform 110 can be formed in any suitable manner, such as by injection molding.

(10) The preform 110 is configured to form container 210 in any suitable manner, such as by blow molding. The container 210 can be any suitable container of any suitable size, such as a 20 ounce, hot-fill container. The container 210 will be further described herein, after the description of the preform 110.

(11) The preform 110 generally includes a first end 112 and a second end 114 opposite thereto. At the first end 112 is a finish portion 120 of the preform 110, which is also a container finish of the container 210. At the first end 112 the finish 120 defines an opening 122 of the preform 110, which also provides a container opening of the container 210. Extending from an outer surface of the finish 120 are threads 124, which can be any suitable threads configured to cooperate with a closure for closing the opening 122. Also extending from the finish 120 is a support ring 126, which can be used for supporting the preform 110 in a stretch blow molding machine, and which may provide the finish 120 with increased strength.

(12) Between the finish 120 and the second end 114, the preform 110 includes a shoulder portion 130, a body portion 132, and a tip or base/heel portion 134. The shoulder portion 130 is adjacent to, or generally adjacent to, the finish 120. The base/heel portion 134 extends from the second end 114 towards the first end 112. The body portion 132 is between the shoulder portion 130 and the base/heel portion 134. As explained in detail herein, the shoulder portion 130 is configured to form a container shoulder 224 of the container 210, and may be configured to form a container neck 222 as well. The body portion 132 is configured to form a container main body portion 226 of the container 210. The base/heel portion 134 is configured to form a container base 240 and a container heel 242 of the container 210.

(13) The preform 110 further includes an outer surface 140 and an inner surface 142, which is opposite to the outer surface 140. The inner and outer surfaces 140 and 142 extend about each of the shoulder portion 130, the body portion 132, and the base/heel portion 134. The inner and outer surfaces 140 and 142 terminate prior to reaching the finish portion 120. At the base/heel portion 134, the outer surface 140 includes a first flat portion F.sub.1, a second flat portion F.sub.2, and a curved portion 150 between the first and second flat portions F.sub.1 and F.sub.2. The curved portion 150 can extend completely between the first and second flat portions F.sub.1 and F.sub.2.

(14) The preform 110 is generally circular, and is closed at the second end 114 by the base/heel portion 134. The base/heel portion 134 tapers inward towards the second end 114. A longitudinal axis A of the preform 110 extends through an axial center of the opening 122 at the first end 112, and through an axial center of the base/heel portion 134 at the second end 114.

(15) With continued reference to FIG. 1 and additional reference to FIG. 2A, the container 210 and the portions of the preform 110 that form different features of the container 210 will now be described in detail. The container 210 includes the finish 120 of the preform 110 at a first or upper end 212 of the container 210. A second or lower end 214 of the container 210 is opposite to the first end 212.

(16) Extending from the finish 120 towards the second or lower end 214 is the container neck 222. From the container neck 222 extends a container shoulder 224. The container shoulder 224 extends to the container main body portion 226, which extends to the container base 240. The sidewall 228 of the container 210 forms at least the container shoulder 224, and the container main body portion 226. The sidewall 228 and the container base 240 together define an internal volume 234 of the container 210.

(17) Between the container shoulder 224 and the container main body portion 226 is an inwardly tapered portion 230 defined by the sidewall 228. The sidewall 228 further defines a plurality of ribs 232A-232E. Any suitable number of ribs 232 can be provided, such as five ribs 232A to 232E as illustrated. The ribs 232 can be any suitable shape or size. For example, the rib 232C can be larger, or recessed further within the container 210, than the other ribs 232A, 232B, 232D, and 323E. The inwardly tapered portion 230 can be recessed further within the container 210 than each of the ribs 232A-232E as illustrated.

(18) The container base 240 generally includes a heel 242 at the second or lower end 214. The base also includes a central portion 244. The longitudinal axis A of the container 210 extends through an axial center of the central portion 244. A diaphragm 246 is between the central portion 244 and the heel 242.

(19) FIG. 2A identifies various sections of the preform 110 at reference numerals 1-20. Specifically, sections 1-5 of the shoulder portion 130 of the preform 110 form the container shoulder 224. Sections 6-13 of the body portion 132 of the preform 110 form the container main body portion 226. Sections 14-20 of base/heel portion 134 of the preform 110 form the container heel 242 and the container base 240. The first and second flat portions F1 and F2 are included with the base/heel portion 134 of the preform 10, and form portions of the container 210 at, and proximate to, the container heel 242. FIG. 2B provides exemplary dimensions and masses for each one of the sections 1-20 of the container 210. The dimensions and masses of FIG. 2B are merely exemplary and thus the sections 1-20 can each have any suitable size and/or mass.

(20) The container 210 can have any suitable dimensions. For example, the preform 110 can be configured such that the container 210 has less than one gram of container material per ounce of container capacity. The preform 110 can further provide the container 210 with the heaviest material band in the heel 242 of the container, and the lightest material band at the base 240, for example, which facilitates movement of the base 240 to absorb vacuum forces.

(21) The preform 110 can be configured such that the container shoulder 224 can have the greatest wall thickness of the container 210, with the greatest thickness of the container shoulder 224 being proximate to the finish 120 and the support ring 126. The container shoulder 224 can have any suitable thickness, such as 0.012 inches, or about 0.012 inches. The container main body portion 226 can have any suitable wall thickness at the sidewall 228, such as 0.01 inches, or about 0.01 inches. The heel 242 can have any suitable thickness to provide added strength and rigidity. For example, the heel 242 can have a thickness of 0.01 inches, or about 0.01 inches. The base 240 can have the thinnest wall thickness of the container 210 to facilitate movement thereof in response to internal changes and pressure and vacuum. The base 240 can have any suitable thickness, such as 0.008 inches, or about 0.008 inches.

(22) With continued reference to FIGS. 1, 2A, and 2B, and additional reference to FIGS. 3A and 3B, various additional exemplary dimensions and features of the preform 110 will now be described. With specific reference to FIG. 3A, the preform 110 includes an outer perimeter P.sub.out at the outer surface 140. Opposite to P.sub.out is inner perimeter P.sub.in, which is at the inner surface 142. The ratio of P.sub.out to P.sub.in can be 1:0.94, or can be about 1:0.94. Thus P.sub.in can be 94% of P.sub.out, or can be about 94% of P.sub.out. P.sub.out can be 69.5 millimeters, or about 69.5 millimeters. P.sub.in can be 65.45 millimeters, or about 65.45 millimeters.

(23) The preform 110 further includes various thicknesses T.sub.1, T.sub.2, T.sub.3, and T.sub.4. T.sub.1 is at the body portion 132, proximate to the base/heel portion 134. T.sub.2 is at the curved portion 150 of the base/heel portion 134. T.sub.3 is at the second flat portion F.sub.2. The second flat portion F.sub.2 increases in thickness along its length in the direction from the second end 114 to the curved portion 150. Therefore, T.sub.3 is thickest proximate to the curved portion 150. T.sub.4 is at the base/heel portion 134 proximate to the second end 114. T.sub.2 can be greater than T.sub.1, which can be greater than T.sub.3, which can be greater than T.sub.4. T.sub.1 can be 3.04 millimeters, or about 3.04 millimeters, which is about 82% of T.sub.2. T.sub.2 can be 3.73 millimeters, or about 3.73 millimeters. T.sub.3 can be 2.59 millimeters, or about 2.59 millimeters, which is about 69% of T.sub.2. T.sub.4 can be 2.5 millimeters, or about 2.5 millimeters, which is about 67% of T.sub.2.

(24) The preform 110 further includes various curve radii R.sub.1, R.sub.2, R.sub.3, R.sub.4, and R.sub.5. Curve radii R.sub.1, R.sub.2, and R.sub.3 are each external curve radii, which are curved surfaces of the outer surface 140 of the preform 110. Curve radii R.sub.4 and R.sub.5 are internal radii at the inner surface 142 of the preform 110. Curve radius R.sub.1 is greater than curve radius R.sub.3, which is greater than curve radius R.sub.2. Curve radius R.sub.4 is greater than curve radius R.sub.5. The curve radii R.sub.1-R.sub.5 can be any suitable size and shape. For example, curve radius R.sub.1 can have a curved radius of 22 millimeters, or about 22 millimeters. Curve radius R.sub.2 can be 6.4 millimeters, or about 6.4 millimeters. Curve radius R.sub.3 can be 8-10 millimeters, or about 8-10 millimeters.

(25) The preform has a total height H.sub.tot extending from the second end 114 to the support ring 126, or about the support ring 126. The shoulder portion 130 of the preform 110 includes a height H.sub.shoulder. The body portion 132 has a height H.sub.body. The base/heel portion 134 includes a height H.sub.base/heel. The dimensions of the different heights H can be any suitable dimensions, and can vary based on the desired size of the container 210. For example, the total height H.sub.tot can be 62.2 millimeters, or about 62.2 millimeters.

(26) The height of the shoulder portion H.sub.shoulder can be 17.75 millimeters, or about 17.75 millimeters. The height of the shoulder portion H.sub.shoulder can be 28% of the total height H.sub.tot, or about 28% of the total height H.sub.tot. The volume of the preform 110 at the shoulder portion 130 can be 4.204 cm.sup.3, or about 4.204 cm.sup.3, which is 31% of a total volume of the preform 110, or about 31% of a total volume of the preform 110.

(27) The height of the body portion H.sub.body can be 29.95 millimeters, or about 29.95 millimeters. The height of the body H.sub.body can be 42% of the total height H.sub.tot, or about 42% of the total height H.sub.tot. The volume of the preform 110 at the body portion 132 can be 5.772 cm.sup.3, or about 5.772 cm.sup.3, which is 43% of the total volume of the preform 110, or about 43% of the total volume.

(28) The height at the base/heel portion H.sub.base/heel can be 18.5 millimeters, or about 18.5 millimeters. The height H.sub.base/heel can be 30% of the total height H.sub.tot, or about 30% of the total height H.sub.tot. The volume at the base/heel portion 134 can be 3.422 cm.sup.3, or about 3.422 cm.sup.3, which can be 26% of the total volume of the preform 110, or about 26% of the total volume.

(29) The preform 110 further includes a total surface area SA.sub.out at the outer surface 140, and a total surface area SA.sub.in at the inner surface 142. The SA.sub.out can be greater than the SA.sub.in and the ratio of the SA.sub.out to the SA.sub.in can be 1:0.72, or about 1:0.72. Therefore, the SA.sub.in can be 72%, or about 72%, of the SA.sub.out. The SA.sub.in and the SA.sub.out can each be any suitable dimension. For example, the SA.sub.in can be 35.9 cm.sup.2, or about 35.9 cm.sup.2. The SA.sub.out can be 49.6 cm.sup.2, or about 49.6 cm.sup.2.

(30) The base/heel portion 134 of the preform 110 can have an outer perimeter P.sub.1, and an inner perimeter P.sub.2. The outer perimeter P.sub.1 is at the outer surface 140 of the preform 110, and the inner perimeter P.sub.2 is at the inner surface 142. The outer perimeter P.sub.1 can be greater than the inner perimeter P.sub.2. A ratio of the outer perimeter P.sub.1 to the inner perimeter P.sub.2 can be 1:0.864, or about 1:0.865. Thus the inner perimeter P.sub.2 can be 86%, or about 86%, of the outer perimeter P.sub.1. The inner and outer perimeters P.sub.1 and P.sub.2 can each have any suitable dimension. For example, the outer perimeter P.sub.1 can be 46.6 millimeters, or about 46.6 millimeters. The inner perimeter P.sub.2 can be 42.86 millimeters, or about 42.86 millimeters.

(31) With additional reference to FIG. 3B, the first and second flat portions F.sub.1 and F.sub.2 can have any suitable length. For example, the first flat portion F.sub.1 can have a length of 4.35 millimeters, or about 4.35 millimeters. The 2.sup.nd flat portion F.sub.2 can have a length of 4.37 millimeters, or about 4.37 millimeters. With respect to an arc of 90 measured from the longitudinal axis A along the base/heel portion 134 to a line L that extends perpendicular to the longitudinal axis A and is generally where the body and base/heel portions 132 and 134 meet, the first flat portion F.sub.1 can extend across radius FR.sub.1, which is 18.6, or about 18.6, and about 25% of the distance between the longitudinal axis A and the line L. The first flat portion F.sub.1 can define a volume V.sub.2 of 0.861 cm.sup.3, or about 0.861 cm.sup.3, of the base/heel portion 134 as measured between the flat portion F.sub.1 and where the longitudinal axis A intersects line L.

(32) The second flat portion F.sub.2 extends 16.15, or about 16.15, of the distance between the longitudinal axis A and the line L across radius FR.sub.2, which is about 21% of the distance between the longitudinal axis A and the line L. The second flat portion F.sub.2 defines a volume V.sub.4 of 0.714 cm.sup.3 between the second flat portion F.sub.2 and intersection between the longitudinal axis A and the line L.

(33) Between the first flat portion F.sub.1 and the line L is a radius R.sub.6, which extends 8.38, or about 8.38, of the distance between the longitudinal axis A and the line L. The radius R.sub.6 defines a volume V.sub.1 of 0.384 cm.sup.3, or about 0.384 cm.sup.3, between the inner surface 142 and where the longitudinal axis A intersects the line L.

(34) Between the first and second flat portions F.sub.1 and F.sub.2 is a radius R.sub.7 of the base/heel portion 134, which extends 13.24, or about 13.24, of the distance between the longitudinal axis A and the line L. The radius R.sub.7 is thus 21.5%, or about 21.5%, of the distance between the longitudinal axis A and the line L. The radius R.sub.7 defines a volume V.sub.3 between the inner surface 142 and where the longitudinal axis A intersects the line L.

(35) Between the second flat portion F.sub.2 and the longitudinal axis A is a radius R.sub.8. The radius R.sub.8 extends 33.36, or about 33.36, of the distance between the longitudinal axis A and the Line L, which is 21.5%, or about 21.5%, of the distance between the longitudinal axis A and the line L. The radius R.sub.8 defines a volume V.sub.5 of 0.732 cm.sup.3, or about 0.732 cm.sup.3, between the inner surface 142 and where the longitudinal axis A intersects the line L.

(36) The first flat portion F.sub.1 can be arranged such that it is angled at 5.6, or about 5.6, relative to the longitudinal axis A. The second flat portion F.sub.2 can be arranged such that it is angled at 36.75, or about 36.75, relative to the longitudinal axis A. Thus, the angle A.sub.2 can be greater than the angle A.sub.1.

(37) Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

(38) The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms a, an, and the may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms comprises, comprising, including, and having, are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.

(39) When an element or layer is referred to as being on, engaged to, connected to, or coupled to another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being directly on, directly engaged to, directly connected to, or directly coupled to another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., between versus directly between, adjacent versus directly adjacent, etc.). As used herein, the term and/or includes any and all combinations of one or more of the associated listed items.

(40) Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as first, second, and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

(41) Spatially relative terms, such as inner, outer, beneath, below, lower, above, upper, and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as below or beneath other elements or features would then be oriented above the other elements or features. Thus, the example term below can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

(42) The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.