US3651981A

US3651981A - Combined container and closure

Info

Publication number: US3651981A
Application number: US8959A
Authority: US
Inventors: Alfred W Kinney
Original assignee: Phillips Petroleum Co
Current assignee: Huhtamaki Consumer Packaging Inc
Priority date: 1970-02-05
Filing date: 1970-02-05
Publication date: 1972-03-28
Anticipated expiration: 1989-03-28

Abstract

A container having a closure retention groove is combined with a closure having a retention bead. The closure is formed so that the portion of the closure between the closure rim and the retention bead grips the portion of the container between the retention groove and the container rim to secure the closure to the container and to form a sanitary seal along the container rim. The retention bead can be interrupted at spaced locations to provide continuous fluid access between the packaging space and the annular space between the closure side wall and the corresponding portion of the container. Indentations can be formed at the junction of the rim and outer skirt of the closure to act as camming surfaces against the curvature of the container rim to raise the closure rim up from the container rim whenever excessive pressure occurs in the container, to thereby vent the container.

Description

United States Patent [451 Mar. 28, 1972 Kinney [54] COMBINED CONTAINER AND CLOSURE [72] Inventor: Alfred W. Kinney, Kansas City, Mo.

[73] Assignee: Phillips Petroleum Company [22] Filed: Feb. 5, 1970 [211 App]. N0.: 8,959

[52] US. Cl..... .220/60 R, 220/44 R, 220/97 C [51] Int. Ch. ..B65d 43/10, 365d 51/16 [58] Field oiSearcli ..220/60 R, 97 C,97 F, 44 R; 229/l. 5 B, 43

[56] References Cited UNITED STATES PATENTS 3,460,711 8/1969 Al-Roy ..220/60 R 3,520,441 7/1970 Fitzgerald ...220/97 C X 3,362,565 1/1968 McCormick. ..220/44 R 3,173,571 3/1965 Cserny ..220/44 R 3,061,139 l0/1962 Edwards ..220/44 R FOREIGN PATENTS OR APPLICATIONS 1,160,783 1/1964 Germany ..220/60 R Primary Examiner-George E. Lowrance Attorney-Young & Quigg [57] ABSTRACT A container having a closure retention groove is combined with a closure having a retention bead. The closure is formed so that the portion of the closure between the closure rim and the retention bead grips the portion of the container between the retention groove and the container rim to secure the closure to the container and to form a sanitary seal along the container n'm. The retention bead can be interrupted at spaced locations to provide continuous fluid access between the packaging space and the annular space between the closure side wall and the corresponding portion of the container. indentations can be formed at the junction of the rim and outer skirt of the closure to act as carnming surfaces against the curvature of the container rim to raise the closure rim up from the container rim whenever excessive pressure occurs in the container, to thereby vent the container.

9 Claims, 8 Drawing Figures PATENTEummalsrz 3,651,981

' sum 1 OF 4 FIG. I

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I SHEET 2 OF 4 FIG. 4 FIG. 5

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sum 3 BF 4 INVENTOR.

A. W. K IN NEY ,4 TTORNEYS PATENTEDMAR'ae I912 3.651.981

' sum u 0F 4 l INVENTOR.

A. W. KINNEY A TTORNE VS COMBINED CONTAINER AND CLOSURE This invention relates to improvements in packaging containers and closures therefor.

Variations in the outer diameter of the retention head on a tinuously, eliminating any sanitary seal.

While the problem of dimensional accuracy is acute with paper containers and closures, it is also serious with therthan in the rim portions of the container or closure.

In accordance with the invention it has been discovered that can be effected at the container rim container rim, thereby venting the container.

Accordingly, it is an object of the invention to provide an improved package. It is an object of the invention to provide an improved closure and container structure whereby the cloreclosable venting structure for a combined container and closure. Another object of the invention is to minimize the eficct of dimensional variations on the fit of a closure and container.

Other objects, aspects and advantages of the invention will be apparent from a study of the specification, the drawings and the appended claims to the invention.

In the drawings FIG. 1 is a side elevational view of a container and closure constructed in accordance with the present invention;

FIG. 2 is a top plan view of the container and closure of FIG. 1;

FIG. 3 is a side elevational view of the closure of FIG. 1;

FIG. 4 is a fragmentary cross-sectional view taken along line 4-4 in FIG. 2 when the package is in a static or non-venting condition; 1

FIG. 5 is a fragmentary cross-sectional view taken along line 5-5 in FIG. 2;

FIG. 6 is a fragmentary cross-sectional view taken along line 4-4 in F IG. 2 when the package is in a venting condition;

FIG. 7 is an elevational view in cross section of a stack of the closures of FIG. 2, the cross section of each closure being along a line corresponding to line 77 in FIG. 2; and

F IG. 8 is a fragmentary cross-sectional view of a stack of the containers ofFIG. l.

Referring now to the drawings in detail, and to FIGS. 1, 4, 5 and 8 in particular, the package 10 comprises a container or cup 11 and a closure, 12. The container 11 is a one-piece integral structure, and can be fabricated by thermoforming a sheet of thermoplastic material. Container 1 1 comprises a bottom wall 13 of any suitable configuration; an outwardly inclined, circumferentially continuous side wall 14 extending upwardly from the periphery of bottom wall 13; stacking ring 15; and rim 16. Where container 11 has a substantially circusure retention groove section 18, spacer section 19, and upper stacking shoulder 21. Annular flange 17 is circumfercntially continuous and extends outwardly in a substantially horizontal direction from the upper extent of side wall 14 to the lower extically from the upper extent of closure retention groove section 18 to the inner extent of upper stacking shoulder 21. In the illustrated container 11, the spacer section 19 has a substantially cylindrical configuration. Closure retention groove section 18 is circumfercntially continuous and is in the form of an inwardly opening, concavely contoured wall section extending substantially vertically from the outer periphery of flange 17 to the lower edge of spacer section 19. The lower portion of groove section 18 serves as the lower stacking shoulder. The upper stacking shoulder 21 curves outwardly and upwardly from the upper extent of spacer section 19 to rim 16. The inner diameter of spacer section 19 is less than the an annular expansion groove, if desired. The retention bead 23 is an inwardly opening, outwardly directed, concavely shaped groove section extending generally upwardly between the periphery of disc 22 and the lower extent of wall section 24. Retention bead 23 is interrupted at circumfercntially 24 to a point on disc 22 which has a significantly smaller diameter than the inner diameter of flange 17. Wall 24 of closure 12 is spaced inwardly from the wall formed by spacer section 19 and stacking shoulder 21 of container 11 to form a packaging space 29 within wall 14 of container 1 1 below disc 22.

Stacking lugs 31 are provided at circumfercntially spaced positions in side wall 24. The stacking lugs 31 are inwardly directed, outwardly opening embossments. Each lug 31 has a substantially vertical or upwardly and slightly inwardly inclined back wall 32, a generally horizontal shoulder 33 and substantially vertical side walls 34. Shoulder 33 extends outwardly in a generally horizontal direction from the upper extent of back or inner wall 32 to wall 24. Shoulder 33 can be curved outwardly and upwardly in conformance with the contour of the lower portion of bead 23. As shown in FIG. 7, the outer diameter of shoulder 33 is at least equal to the outer diameter of the corresponding portion of bead 23 so that the bead 23 of one closure rests upon the shoulder 33 of the next lower closure in a nested stack of superimposed closures. The circumferential discontinuity of the stacking shoulders 33 readily permits air to flow out of or into the space between superimposed closures during stacking or denesting operations.

Referring now to FIG. 4, upon insertion of closure 12 into container 11, bead 23 cams inwardly on the curved upper shoulder 21 and then snaps into closure retention groove 18. Notches 27 permit continuous outflow of air from the interior of the package during the insertion of closure 12 into container 11, thereby preventing a buildup of excessive pressure in the package during the capping operation. The upper sur face of bead 23 contacts the inner surface of the upper portion of retention groove 18 at point 35. The underside of rim 25 contacts the top of rim 16 at point 36. This results from the formation of closure 12 in such a manner that the distance between

points

35 and 36 in the unstressed closure is less than the distance between

points

35 and 36 on the uncapped container. Thus, the upper portion of bead 23, wall 24 and rim 25 act as a C-clamp to grip the mating surfaces of container 11 to thereby removably secure the closure 12 to the container 11. The contact of closure rim 25 and container rim l6'is circumferentially continuous and serves as a seal for the capped container. In contrast to containers which provide a sealing surface at the top or bottom of the closure retention bead, the present configuration provides a seal at the top of the container rim to insure sanitary conditions for the entire interior of the container.

Closure 12 is provided with a plurality of circumferentially spaced venting earns 37, bridging rim 25 and depending flange 26. Cams 37 project inwardly from flange 26 and downwardly from rim 25 to form a camming surface which is inclined downwardly at an acute angle to the horizontal reference. The earns 37 are positioned at least closely adjacent the outwardly and downwardly curving portion of rim l6, and camming contact therebetween occurs during venting of the package. Preferably this contact is made in the first 45 of curvature of rim 16 outwardly and downwardly from the horizontal. When the pressure in packaging space 29 and annular space 28 is not excessive, the relationship of the closure 12 and the container 11 is illustrated in FIG. 4. Upon the occurrence of excessive pressure in packaging space 29 and annular space 28, the upstanding wall 24 of closure 12 is forced inwardly, causing the earns 37 to contact and slide on the upper half of the upper and outer quadrant of rim 16. The camming action causes rim 25 of the closure 12 to move upwardly from rim 16 to the position shown in FIG. 6, thereby providing a continuous passageway to the atmosphere from packaging space 29 through annular space 28 and through the space between rim l6 and rim 25 and depending flange 26. The inner diameter of depending flange 26 is sufficiently greater than the outer diameter of rim 16 to provide a clearance therebetween even when the closure is contorted to the venting condition. Upon the release of the excessive pressure, the closure and container return to the relationship shown in FIG. 4.

Thermoformed containers and thermoformed closures are customarily formed in female molds. This has the advantage that the outside dimensions of the containers are substantially constant; however, the wall thickness varies within each container. The retention bead 23 of closure 12 is relatively thin because of the double stretching to which the thermoplastic sheet material is subjected. The sheet is initially stretched as it is drawn downwardly into the main mold cavity, and then a portion thereof is additionally stretched as that portion is drawn into the mold groove which forms bead 23. A similar double stretching action occurs in the formation of closure retention groove 18 in container 11. The increased resiliency of the thinner wall of bead 23 assists in the insertion of the closure 12 into container 11 as the bead 23 will flex inwardly to pass the spacer section 19 of container 11 and then snap outwardly into groove 18. However, the thinner wall of bead 23 is more subject to a stress fold than rim 25, which could prevent a normally closed venting groove from being opened or which could result in the formation of an undesired continuously open venting passageway.

The rim 25 and depending skirt 26 will normally have the greatest thicknesses of any part of a thermoforrned closure 12. Similarly, the rim 16 will normally have the greatest thickness of any part of' a thermoformed container 11. These greater thicknesses also normally result in the greatest rigidity and dimensional accuracy for any portion of the container or closure. This results in a more effective seal where the seal is between the container rim and the closure rim than where the seal is between the retention bead and the retention groove. The location of the venting cams at the junction of the rim 25 and shirt 26 also takes advantage of the greater rigidity and dimensional accuracy to provide a more effective reclosable venting action than would be obtained with reclosable vents in the retention bead or in the retention groove.

While the invention has been illustrated with a container and closure having substantially circular horizontalcross sections, other configurations can be utilized, for example, oval, rectangular with at least the comers being rounded and more preferably with the sides being bowed outwardly, and the like. Other reasonable variations and modifications are possible within the scope of the foregoing disclosure, the drawings and the appended claims to the invention.

I claim: I. A package comprising a container and a closure therefor; said container comprising a bottom wall, an upstanding wall extending generally upwardly from the periphery of said bottom wall, a rim forming the mouth of said container and having an outwardly and downwardly curving peripheral portion, and a ring section extending generally upwardly from the upper extent of said upstanding wall to said rim and having a closure retention groove formed therein; said closure comprising a diaphragm, a side wall, an outwardly directed, inwardly opening retention bead extending upwardly from the periphery of said diaphragm to the lower extent of said side wall, and a rim extending outwardly from the upper extent of said side wall; said retention bead being dimensioned to snap into said closure retention groove; said rim of said closure extending outwardly over said rim of said container and in contact therewith; the distance between the point of contact of said rim of said container and the rim of said closure and the point of contact of said retention bead and said closure retention groove being greater than the distance between the same points in the unstressed closure before the unstressed closure is applied to said container, so that the portion of said closure between said points of contact serves as a C-clamp to grip the mating portion of said container to thereby secure said closure to said container;

said retention bead being interrupted by at least one venting groove which extends to a point on said diaphragm which is spaced inwardly a significant distance from the inner surface of said ring section to provide a continuously open fluid communication between the packaging space within said container below said diaphragm and the annular space between said side wall and the laterally adjacent portion of said container; and camming means formed in said rim of said closure to contact said outwardly and downwardly curving peripheral portion of said rim of said container to effect a lifting of the closure rim from the container rim upon the occurrence of excessive pressure in said packaging space to thereby vent said packaging space.

2. A package in accordance with claim 1 wherein said container and said closure have substantially circular horizontal cross sections, said upstanding wall extends upwardly and outwardly from the periphery of said bottom wall, and said side wall of said closure extends upwardly and outwardly from the upper extent of said retention bead.

3. A package in accordance with claim 2 wherein said ring section comprises an annular flange extending outwardly from the upper extent of said upstanding wall, an inwardly opening closure retention groove section extending generally upwardly from the outer periphery of said annular flange, a spacer section extending upwardly substantially vertically from the upper extent of said closure retention groove section, and an upper stacking shoulder extending generally outwardly and upwardly from the upper extent of said spacer section to the inner extent of said rim.

4. A package in accordance with claim 3 wherein said container is a one-piece integral thermoformed structure; wherein said upstanding wall and said ring section are circumferentially continuous; wherein said closure retention groove.

section is an inwardly opening, concavely contoured wall section extending substantially vertically from the outer periphery of said flange to the lower extent of said spacer section; and wherein said upper shoulder is curved outwardly and upwardly in a contour conforming to the contour of the lower portion of said concavely contoured wall section so that the lower portion of the concavely contoured wall section of one container will rest upon the upper stacking shoulder of the next lower container in a stack of superimposed identical containers.

5. A package in accordance with claim 4 wherein said closure is a one-piece integral thermoformed structure; wherein 10 junction of said rim of said closure and said depending skirt,

said camming grooves contacting said outwardly and downwardly curved peripheral portion of said rim of said container to effect a lifting of the closure rim from the container rim upon the occurrence of excessive pressure in said packaging space to thereby vent said packaging space.

7. A package in accordance with claim 1 wherein said closure further comprises a continuous skirt depending from the outer periphery of the rim of said closure and wherein said camming means comprises a plurality of downwardly and inwardly directed indentations formed at the junction of said closure rim and said depending skirt.

8. A package in accordance with claim 7 wherein said retention head is interrupted at circumferentially spaced locations by a plurality of said venting grooves.

9. A package in accordance with claim 8 wherein said indentations contact said outwardly and downwardly curving peripheral portion of said container rim in the first 45 of curvature of said curving portion from the horizontal.

Claims

1. A package comprising a container and a closure therefor; said container comprising a bottom wall, an upstanding wall extending generally upwardly from the periphery of said bottom wall, a rim forming the mouth of said container and having an outwardly and downwardly curving peripheral portion, and a ring section extending generally upwardly from the upper extent of said upstanding wall to said rim and having a closure retention groove formed therein; said closure comprising a diaphragm, a side wall, an outwardly directed, inwardly opening retention bead extending upwardly from the periphery of said diaphragm to the lower extent of said side wall, and a rim extending outwardly from the upper extent of said side wall; said retention bead being dimensioned to snap into said closure retention groove; said rim of said closure extending outwardly over said rim of said container and in contact therewith; the distance between the point of contact of said rim of said container and the rim of said closure and the point of contact of said retention bead and said closure retention groove being greater than the distance between the same points in the unstressed closure before the unstressed closure is applied to said container, so that the portion of said closure between said points of contact serves as a C-clamp to grip the mating portion of said container to thereby secure said closure to said container; said retention bead being interrupted by at least one venting groove which extends to a point on said diaphragm which is spaced inwardly a significant distance from the inner surface of said ring section to provide a continuously open fluid communication between the packaging space within said container below said diaphragm and the annular space between said side wall and the laterally adjacent portion of said container; and camming means formed in said rim of said closure to contact said outwardly and downwardly curving peripheral portion of said rim of said container to effect a lifting of the closure rim from the container rim upon the occurrence of excessive pressure in said packaging space to thereby vent said packaging space.

4. A package in accordance with claim 3 wherein said container is a one-piece integral thermoformed structure; wherein said upstanding wall and said ring section are circumferentially continuous; wherein said closure retention groove section is an inwardly opening, concavely contoured wall section extending substantially vertically from the outer periphery of said flange to the lower extent of said spacer section; and wherein said upper shoulder is curved outwardly and upwardly in a contour conforming to the contour of the lower portion of said concavely contoured wall section so that the lower portion of the concavely contoured wall section of one container will rest upon the upper stacking shoulder of the next lower container in a stack of superimposed identical containers.

5. A package in accordance with claim 4 wherein said closure is a one-piece integral thermoformed structure; wherein said retention bead is an inwardly opening, outwardly directed, concavely shaped groove section; and wherein said side wall has a plurality of stacking lugs formed therein.

6. A package in accordance with claim 5 wherein said retention bead is interrupted at circumferentially spaced locations by a plurality of said venting grooves; wherein said closure further comprises a skirt depending from the outer periphery of the rim of said closure; and wherein said camming means comprises inwardly directed camming grooves formed at the junction of said rim of said closure and said depending skirt, said camming grooves contacting said outwardly and downwardly curved peripheral portion of said rim of said container to effect a lifting of the closure rim from the container rim upon the occurrence of excessive pressure in said packaging space to thereby vent said packaging space.

8. A package in accordance with claim 7 wherein said retention bead is interrupted at circumferentially spaced locations by a plurality of said venting grooves.

9. A package in accordance with claim 8 wherein said indentations contact said outwardly and downwardly curving peripheral portion of said container rim in the first 45* of curvature of said curving portion from the horizontal.