US20070102389A1 - Tamper-evident closure - Google Patents

Abstract

A tamper-evident closure system is provided for a container. The system has a body for extending from the container at the container opening. The body defines a dispensing orifice and an attachment surface. The system includes a lid for being moved between a closed position and an open position. An anchor member is provided for being attached to the body attachment surface when the lid is first closed on the body. At least one frangible web initially connects the anchor member with the lid so that the frangible web breaks when the lid is initially lifted from the closed position.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S)
• Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
• Not applicable.
REFERENCE TO A MICROFICHE APPENDIX
• Not applicable.
TECHNICAL FIELD
• This invention relates to a tamper-evident closure system for a container. The invention is particularly suitable for incorporation in a dispensing closure for use with a squeezable container.
BACKGROUND OF THE INVENTION AND TECHNICAL PROBLEMS POSED BY THE PRIOR ART
• There are a variety of types of conventional closures which function generally satisfactorily in applications for which they are designed. One type of prior art closure includes a body or base for being attached to the top of a container. The body defines a dispensing orifice. The system further includes a lid which is mounted on the base or body and which can be lifted up to open the dispensing orifice. See, for example, U.S. Pat. No. 6,644,487.
• The U.S. Pat. No. 6,644,487 discloses a design which also includes tamper-evident frangible webs for connecting the lid to the body and for initially preventing the lid from being lifted away from the body unless and until a sufficient lifting force is applied to the lid to break the webs, and such breakage serves as a tamper-evident feature. While such a design offers significant advantages, it would be desirable to provide a further improved tamper-evident closure system.
• In particular, it would be desirable to provide an improved design in which the tamper-evident feature can be optionally more strongly integrated into the closure system and/or can be optionally made even more noticeable to the user (before the tamper-evident feature is broken prior to the lid being initially opened, as well as after the tamper-evident feature has been broken and the lid is re-closed).
• It would also be advantageous if such an improved tamper-evident closure system could also be adapted for use with a one-piece, unitary closure system as well as with a two-piece, or other multiple-piece, closure system.
• It would also be beneficial if such an improved tamper-evident closure system could optionally readily accommodate the connection of the lid to the body with a hinge structure, either a hinge structure that is unitary with both the lid and body, or a two-piece hinge structure that is part of a separately formed lid and separately formed body which can be assembled together.
• It would also be advantageous if such an improved tamper-evident closure system could optionally incorporate the tamper-evident feature in a way which does not hinder access to, or obstruct, the front of the lid where a thumb lift tab might be employed.
• It would also be desirable to provide a tamper-evident closure system which would not require the use of a freshness seal or liner across the closure or container opening, and that would have a minimum number of components so as to facilitate manufacture and assembly.
• It would also be advantageous to provide a closure system with the capability for accommodating optional tamper-evident features between the container and closure system body that can readily indicate to a consumer that the closure system has been initially removed from the container.
• It would also be beneficial if a closure system could readily accommodate its manufacture from at least a thermoplastic material, or other material.
• It would also be advantageous if such an improved closure system could accommodate bottles, containers, or packages which have a variety of shapes and which are constructed from a variety of materials.
• Further, it would be desirable if such an improved system could accommodate efficient, high-quality, high-speed, large volume manufacturing techniques with a reduced product reject rate to produce products having consistent operating characteristics unit-to-unit with high reliability.
BRIEF SUMMARY OF THE INVENTION
• The present invention can be incorporated into a closure system that may include one or more of the above-discussed, desired features.
• The present invention provides an improved tamper-evident closure system for a container that has an opening to the container interior. The system can be readily operated by the user to initially open the system.
• If desired, the improved system can accommodate a tamper-evident feature that is optionally more strongly integrated into the closure and/or is optionally more readily visible so that the condition or status of the feature (i.e., unbroken or broken) can be easily observed.
• The initial opening operation of the inventive, tamper-evident closure system lid does not produce a separate, loose piece which must be discarded. The tamper-evident closure system can be employed with a one-piece or multi-piece closure body and lid design. Further, the tamper-evident closure system readily accommodates the employment of a thumb lift tab on the lid and also readily accommodates a unitary, or multi-piece, hinge structure between the lid and the body. The system also accommodates the use of other, optional, tamper-evident features between the closure body and the container.
• According to a first aspect of a presently preferred embodiment of the invention, the tamper-evident feature is more strongly integrated into the closure system by welding. The system includes a body that is either a separate structure for attaching to, and extending from, the container at the container opening or is a unitary extension of the container at the opening.
• The body has
• • (1) at least one orifice for communicating with the container opening, and
  • (2) a thermoplastic attachment surface.
• A lid is adapted to be disposed on the body for accommodating lifting of the lid relative to the at least one orifice between (1) a closed position over the at least one orifice, and (2) an open position away from the at least one orifice.
• An anchor member is provided with a thermoplastic attaching portion for being welded to the body attachment surface when the lid is first in the closed position. In the preferred embodiment, ultrasonic welding is employed.
• At least one frangible web extends between the lid and the anchor member for initially connecting the anchor member with the lid, and the web is subsequently broken when the lid is first lifted from the closed position.
• According to a second aspect of the invention, a more visible tamper-evident feature in a closure system is provided for a container that has an opening to the container interior. This second aspect of the invention may be provided in the closure system without the above-described first aspect of the invention, or vice versa. The closure system includes a body that is either a separate structure for attaching to, and extending from, the container at the opening or is a unitary extension of the container at the opening. The body has at least one orifice for communicating with the container opening.
• A lid is adapted to be disposed in the body for accommodating lifting of the lid relative to the at least one orifice between (1) a closed position over the at least one orifice, and (2) an open position away from the at least one orifice. The lid has a lower edge.
• An anchor member is non-removably fixed to the body when the lid is first in the closed position to define a vertical gap between the anchor member and the lid lower edge.
• At least one frangible web extends across the gap between the lid lower edge and the anchor member for initially connecting the anchor member with the lid for subsequently being broken when the lid is first lifted from the closed position. The frangible web is highly visible in the gap.
• In a most preferred form of the invention, both the above-described first aspect of the invention and the above-described second aspect of the invention are included together in the closure system.
• According to yet another aspect of the invention, a method is provided for making a tamper-evident closure system for a container that has an opening to the container interior. The method comprises the steps of:
• (A) molding from thermoplastic material a body that
• • (1) is either a separate structure for attaching to, and extending from, the container at the opening or is a unitary extension of the container at the opening,
  • (2) has at least one orifice for communicating with the container opening, and
  • (3) has a thermoplastic attachment surface;
• (B) molding from thermoplastic material a top structure comprising (1) a lid, (2) an anchor member that has an attaching portion, and (3) at least one frangible web that extends between, and is unitary with, the lid and the anchor member wherein the lid is adapted to be disposed on the body for accommodating lifting of the lid relative to the at least one orifice between (i) a closed position over the at least one orifice, and (ii) an open position away from the at least one orifice;
• (C) mounting the top structure on the body with the lid disposed on the body in the closed position and with the anchor member attaching portion located adjacent the body attachment surface; and
• (D) welding the anchor member attaching portion to the body attachment surface when the lid is first in the closed position to initially connect the anchor member with the lid so that the at least one frangible web can be subsequently broken when the lid is first lifted from the closed position.
• Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention, from the claims, and from the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
• In the accompanying drawings that form part of the specification, and in which like numerals are employed to designate like parts throughout the same,
• FIG. 1 is a perspective view of an exemplary tamper-evident closure system in the form of a separate dispensing closure according to a preferred embodiment of the invention, and the closure is shown in a closed configuration, before installation on a container, and from a vantage point generally above, or from the top of, the closure;
• FIG. 2 is a view similar toFIG. 1, butFIG. 2 shows the lid in the open position with the tamper-evident feature having been broken;
• FIG. 3 is an enlarged, fragmentary, cross-sectional view taken generally along the plane3-3 inFIG. 1, butFIG. 3 further shows the closure installed on the neck of a container and shows part of the lower tamper-evident band of the closure turned upwardly to engage a flange on the container neck;
• FIG. 4 is an enlarged, cross-sectional view taken generally along the plane4-4 inFIG. 1, andFIG. 4 shows the closure prior to the closure being installed on the neck of the container, andFIG. 4 further shows the lower tamper-evident band in the as-molded, downwardly depending configuration prior to being turned up under the flange on the container neck;
• FIG. 5 is an enlarged, cross-sectional view similar toFIG. 3, butFIG. 5 shows the closure (1) prior to the lid anchor member being welded to the closure body, and (2) prior to the closure being installed on the neck of a container, andFIG. 5 further shows the lower tamper-evident band in the as-molded, downwardly depending configuration prior to being turned up under the flange on the container neck;
• FIG. 6 is a perspective view of the closure body prior to the lid being initially mounted on the body by the manufacturer and prior to the completed closure being installed on the container;
• FIG. 7 is a enlarged, cross-sectional view taken generally along the plane7-7 inFIG. 6, andFIG. 7 shows the closure body prior to being installed on the neck of the container, andFIG. 7 further shows the lower tamper-evident band in the as-molded, downwardly depending configuration prior to being turned up under the flange on the container neck;
• FIG. 8 is a front perspective view of the closure lid prior to the lid being mounted on the closure body by the manufacturer;
• FIG. 9 is a rear perspective view of the lid prior to the lid being mounted on the closure body by the manufacturer;
• FIG. 10 is a top plan view of the closure lid prior to the lid being mounted on the closure body by the manufacturer;
• FIG. 11 is a bottom view of the lid prior to the lid being mounted on the closure body by the manufacturer;
• FIG. 12 is a cross-sectional view taken generally along the plane12-12 inFIG. 10;
• FIG. 13 is a cross-sectional view taken generally along the plane13-13 inFIG. 10;
• FIG. 14 is a front elevation view of the lid taken generally along the plane14-14 inFIG. 10;
• FIG. 15 is a greatly enlarged view of the region within the oval designated asFIG. 15 inFIG. 12;
• FIG. 16 is a greatly enlarged cross-sectional view of the area within the circle designatedFIG. 16 inFIG. 13; and
• FIG. 17 is a view similar toFIG. 15, butFIG. 17 shows the structure after a tamper-evident feature has been broken.
DETAILED DESCRIPTION
• While this invention is susceptible of embodiment in many different forms, this specification and the accompanying drawings disclose only some specific forms as examples of the invention. The invention is not intended to be limited to the embodiments so described, however. The scope of the invention is pointed out in the appended claims.
• For ease of description, most of the figures illustrating the invention show a closure system in the typical orientation that it would have at the top of a container when the container is stored upright on its base, and terms such as upper, lower, horizontal, etc., are used with reference to this position. It will be understood, however, that the closure system of this invention may be manufactured, stored, transported, used, and sold in an orientation other than the position described.
• The closure system of this invention is suitable for use with a variety of conventional or special containers having various designs, the details of which, although not illustrated or described, would be apparent to those having skill in the art and an understanding of such containers. The container, per se, described herein forms no part of, and therefore is not intended to limit, the present invention. It will also be understood by those of ordinary skill that novel and non-obvious inventive aspects are embodied in the described exemplary closure systems alone.
• A presently preferred embodiment of a tamper-evident closure system of the present invention is illustrated inFIG. 17 and is designated generally therein byreference number20 inFIG. 1. In the preferred embodiment illustrated, theclosure system20 is provided in the form of aseparate closure20 which is adapted to be mounted or installed on a container22 (FIG. 3) that would typically contain a fluent material. Thecontainer22 includesbody24 and aneck26 as shown inFIG. 3. Theneck26 defines anopening28 to the container interior. Thecontainer neck26, in the preferred embodiment illustrated inFIG. 3, has an external,male thread29 for engaging theclosure20.
• Thebody24 of thecontainer22 may have any suitable configuration, and the upwardly projectingneck26 may have a different cross-sectional size and/or shape than thecontainer body24. (Alternatively, thecontainer22 need not have aneck26, per se. Instead, thecontainer22 may consist of just a body with an opening.) Thecontainer22 may have a rigid wall or walls, or may have a somewhat flexible wall or walls.
• Although the container, per se, does not necessarily form a part of the broadest aspects of the present invention, per se, it will be appreciated that at least a body portion of thesystem20 of the present invention optionally may be provided as a unitary portion, or extension, of the top of the container. However, in the preferred embodiment illustrated, thesystem20 is a separate unit (e.g., a closure) which can be either one-piece or multiple pieces, and which is adapted to be removably or non-removably installed on a previously manufacturedcontainer22 that has anopening28 to the container interior. Hereinafter, theclosure system20 will be more simply referred to as theclosure20.
• Theclosure20 is adapted to be used with acontainer22 having anopening28 to provide access to the container interior and to a product contained therein. Theclosure20 can be used with many materials, including, but not limited to, relatively low or high viscosity liquids, creams, gels, suspensions, mixtures, lotions, pastes, particulates, granular materials, small pieces or items, etc. as constituting a food product, a beverage product, a personal care product, an industrial or household cleaning product, or other compositions of matter (e.g., compositions for use in activities involving manufacturing, commercial or household maintenance, construction, agriculture, etc.).
• Thecontainer22 with which theclosure20 may be used would typically be a squeezable container having a flexible wall or walls which can be grasped by the user and squeezed or compressed to increase the internal pressure within the container so as to force the product out of the container and through the opened closure. Such a flexible container wall typically has sufficient, inherent resiliency so that when the squeezing forces are removed, the container wall returns to its normal, unstressed shape. Such a squeezable wall container is preferred in many applications but may not be necessary or preferred in other applications. For example, in some applications it may be desirable to employ a generally rigid container, and to pressurize the container interior at selected times with a piston or other pressurizing system. Also, the interior of the container need not be pressurized at all. Instead, if the closure is large enough, the product could be accessed by reaching through the open closure with a hand, spoon or straw, or the package could be inverted to let the product discharge through the opened closure solely under the influence of gravity.
• It is presently contemplated that many applications employing theclosure20 will conveniently be realized by molding some or all of the components of theclosure20 from suitable thermoplastic material or materials. In the preferred embodiment illustrated, the components of the closure could each be molded from a suitable thermoplastic material, such as, but not limited to, polypropylene. The closure components may be separately molded from the same material or from different materials. The materials may have the same or different colors and textures.
• As can be seen inFIG. 5, the closure system orclosure20 includes, inter alia, two basic components, (1) a base orbody30, and (2) alid40 which is adapted to be carried on thebody30. Theclosure20 also includes tamper-evident features described in detail hereinafter.
• Thelid40 is movable between a closed position over the body as shown inFIG. 1 and an open position as shown inFIG. 2. Thelid40 may be a separate component which is completely removable from theclosure body30, or thelid40 may be tethered to thebody30 with a strap, or thelid40 may be hinged to thebody30 as shown inFIG. 2 so as to accommodate pivoting movement from the closed position to the open position.
• As can be seen inFIG. 7, theclosure body30 includes aspout42 defining a dispensingorifice44 which opens to the hollow interior of theclosure body30 and which therefore communicates with theopening28 in thecontainer neck26 when theclosure20 is mounted on thecontainer22 as shown inFIG. 4. The interior of thespout42 contains an apertured baffle structure45 (FIGS. 3-7) for controlling the flow of the discharging fluid product. Thebaffle structure45 may be omitted altogether, or other spout interior structures may be included (e.g., a discharge valve).
• As shown inFIGS. 6 and 7, at the bottom of thespout42, theclosure body30 has a peripheralupper deck46. The peripheralupper deck46 is defined at its outer edge by a generallyvertical wall48 as can be seen inFIGS. 6 and 7. Surrounding the lower edge of thevertical wall48 is anintermediate deck50. Theintermediate deck50 is defined at its outer edge by a generallyvertical wall52. At the bottom edge of thevertical wall52 is alower deck54. Thelower deck54 defines an attachment surface and functions to accommodate a thermoplastic weld attachment of a tamper-evident feature on thelid40 as described in detail hereinafter.
• As can be seen inFIGS. 6 and 7, the rear of theclosure body30 includes a bearing member comprising two, spaced-apartwalls80 which together define between them an upwardlyopen channel82. As shown inFIG. 7, the upper, distal end portion of eachwall80 extends toward theother wall80 over thechannel82 to define a reducedwidth passage84 to thechannel82. The bottom of thechannel82 includes a narrower recess orgroove86.
• As can be seen inFIGS. 6 and 7, theclosure body30 has anannular skirt90 extending downwardly form the upper portion of theclosure body30. The interior surface of theskirt90 defines afemale thread92. As illustrated inFIG. 5, the closurebody skirt thread92 is adapted to threadingly engage the exterior,male thread29 on thecontainer neck26.
• Alternatively, theclosure skirt90 could be provided with some other container connecting means, such as a snap-fit bead or groove (not illustrated) in place of thethread92 for engaging a container neck groove or bead (not illustrated), respectively. Theclosure body30 could also be permanently attached to thecontainer22 by means of induction melting, ultrasonic melting, gluing, or the like, depending on materials used for theclosure body30 andcontainer22. Theclosure body30 could also be formed as a unitary part, or extension, of thecontainer22.
• Theclosure body skirt90 may have any suitable configuration for accommodating an upwardly projectingneck26 or other portion of thecontainer22 received within the particular configuration of theclosure body30, and the main part of thecontainer22 may have a different cross-sectional shape than thecontainer neck26 andclosure body30.
• An optional seal or liner (not illustrated) may be sealed across the top of thecontainer neck26 or, alternatively, may be sealed across an interior region or underside of the upper portion of theclosure body30. However, if the function of a tamper-evident seal or freshness seal as provided by such a liner is not needed or desired in a particular application, then the liner may, of course, be omitted.
• Also, if desired, theclosure body30 may be provided with an interior, annular seal96 (FIGS. 6 and 7) extending downwardly from the underside of the upper portion of theclosure body30. Such aseal96 could be “plug” profile seal, as illustrated, or a “crab's claw” seal, a flat seal, a V seal, or some other such seal, depending upon the particular application and depending upon whether or not a liner is employed.
• In the preferred form of the invention illustrated, theclosure body skirt90 has a generally annular configuration. However, theclosure body skirt90 may have other configurations. For example, theclosure body skirt90 might have a prism or polygon configuration adapted to be mounted to the top of a container neck having a polygon configuration. Such prism or polygon configurations would not accommodate the use of a threaded attachment, but other means of attachment could be provided, such as a snap-fit bead and groove arrangement, or the like. However, if the closure body included a double wall defining a polygon outer skirt and a cylindrical inner attachment wall, then the cylindrical inner attachment wall could be provided with a thread for engagement with a threaded container.
• In one preferred form of the invention as shown inFIG. 5, theclosure body30 incorporates a conventional or special tamper-evident ring100 along the bottom edge of theclosure body skirt90 for cooperation with acontainer22 that has a retention flange104 (FIG. 3) below thecontainer neck thread26. As shown inFIG. 5, the tamper-evident ring100 is initially molded as a downwardly extending, unitary flange on the bottom of theclosure body skirt90. Prior to the installation of theclosure body30 on a container, such as on thecontainer22 illustrated inFIG. 3, the lower half of the tamper-evident ring100 is deformed or bent radially inwardly and upwardly. Then, theclosure body30 is lowered onto thecontainer neck26 and threadingly rotated relative to thecontainer neck26. The upwardly bent tamper-evident ring100 passes over thecontainer neck thread29 and over the containerneck retention flange104. The upwardly bent portion of the tamper-evident ring100 snaps inwardly below the containerneck retention flange104 as shown inFIG. 3. This resists removal of theclosure body30 if a user attempts to rotate theclosure body30 in an unscrewing direction. However, the tamper-evident band orring100, in the preferred form, is connected to the bottom end of theclosure body skirt90 by a very thin portion or portions of material (which may have, for example, circumferentially spaced-apart notches or a scored groove or a molded groove (not shown)). If the user attempts to unscrew theclosure body30 with a sufficient amount of torque, then the interconnecting, thin portion of material will break, and the tamper-evident band100 will separate from the bottom of theclosure body skirt90. This will serve as an indication that theclosure body30 has been unscrewed, at least partially, from the fully assembled configuration.
• The use of a tamper-evident ring orband100 is an entirely optional feature of the illustrated embodiment, and it does not form a necessary part of the present invention. Indeed, if theclosure body30 is non-releasably attached to the container neck26 (as with adhesive, thermal bonding, irreversible snap-fit configurations, etc.), then the tamper-evident ring100 would provide no additional benefit. Similarly, a tamper-evident ring100 would provide no additional benefit if theclosure body30 is formed as a unitary molded extension of thecontainer neck26.
• As shown inFIGS. 8 and 9, thelid40 includes atop wall122 and askirt124. The front of thelid40 has an indentation orrecess126 in theskirt124. Athumb lift tab128 projects outwardly from the top portion of thelid40 over therecess126. As can be seen inFIG. 9, theskirt124 has aflat wall section125 at the rear of thelid40. Projecting outwardly from theflat wall section125 is a pair of rearwardly extending lugs130. Ashaft132 extends between, and connects, thelugs130 at a location where theshaft132 is spaced from the lid skirtflat wall section125. Theshaft132 has a centrally located, outwardly projecting ridge orbead133.
• With reference toFIG. 4, thelid shaft132 is received within the upwardlyopen channel82 defined at the rear of theclosure body30. Theshaft132 has a width dimension or diameter that is greater than theopening84 between the upper, distal ends of thewalls80 which define the sides of thechannel82. This provides a snap-fit engagement and retains thelid shaft132 on a fixed axis relative to theclosure body30 so as to accommodate pivoting movement of thelid40 relative to theclosure body30 between the full closed position (FIG. 1) and the full open position (FIG. 2). The shaft ridge or bead133 (FIG. 4) is received in the groove86 (FIGS. 4 and 6) at the bottom of thechannel82 when thelid40 is fully opened (FIG. 2) to provide a detent engagement that increases the resistance to rotation of thelid40 away from the open position. This helps keep thelid40 open at about 80°, and helps prevent theopen lid40 from flopping around.
• As can be seen inFIG. 12, thelid40 optionally may include, and preferably includes, a plug or spud140 projecting downwardly from the underside of the lidtop wall122. Anannular sealing member142 projects from the underside of thelid40 around thespud140. Themember142 has a radially inwardly projecting sealingbead144. As shown inFIG. 4, thespud140 is adapted to be received within the dispensingorifice44 of thespout42. In the preferred embodiment illustrated inFIGS. 4, the dispensingorifice44 is a substantially cylindrical orifice, and the exterior of the lid plug or spud140 has a generally cylindrical surface. The diameter of the exterior surface of the lid spud140 is slightly greater than the internal diameter of thebody dispensing orifice44. This provides an interference fit to effect good sealing engagement. Either thespud140 or thespout42, or both, have sufficient flexibility to accommodate such an interference fit providing leak-tight sealing capability. Thelid sealing member142 and itsbead144 are optional features that may be included so that the bead can sealingly engage the upper, exterior surface of thespout42. Thespud140 is also an optional feature. Theclosure20 could alternatively be provided with just thespud140 alone, or thelid member142 alone, or both the spud140 and lid member142 (as in the illustrated, preferred embodiment).
• According to the present invention, a unique tamper-evident feature is provided for indicating that thelid40 has been initially moved away from the fully closed configuration (FIG. 1) toward the fully opened position (FIG. 2). The tamper-evident feature involves cooperation between thelid40 andclosure body30. As shown inFIGS. 1, 3,7, and9, the tamper-evident feature includes at least oneanchor member152 which is initially connected to thelid40 with one or more frangible members orwebs160. The combination of thelid40,webs160, andanchor members152 may be characterized as a top structure for being initially mounted on, and attached to, theclosure body30.
• In the preferred embodiment, there are twoanchor members152--one provided on each side of thelid40 along the bottom edge of thelid40, but spaced a distance Y (FIGS. 14-16) below the lid skirt bottom edge. In the preferred embodiment illustrated inFIGS. 8 and 9, there are a plurality offrangible webs160 in the form of spaced-apart bridges extending between eachanchor member152 and thelid skirt124.
• In the illustrated preferred embodiment, eachanchor member152 includes a generally vertically inner surface153 (FIGS.12,.13,15,16, and17) that faces radially inwardly and that is connected to the lower portion of eachfrangible web160. Thewebs160 are initially molded simultaneously with, and as part of the unitary top structure that includes, thelid40 andanchor members152. Eachanchor member152 is a generally arcuate bar. In other contemplated embodiments (not illustrated), each anchor member need not be an arcuate bar. Eachanchor member152 includes an attaching portion162 (FIGS. 13, 14, and16) which, in the illustrated preferred embodiment, is defined by the underside or bottom surface of themember152. Preferably, the attachingportion162 is initially molded as the bottom surface of theanchor member152 and also includes a downwardly projecting protrusion orprotuberance164 that has a triangular transverse cross section for facilitating the thermoplastic welding attachment of theanchor member152 to the closurebody attachment surface54 as described in detail hereinafter.
• In the presently contemplated preferred form of the invention, the manufacturer can readily mold thelid40,webs160, and anchor members152 (with the protuberances164) together as a single, unitary component (i.e., the top structure), and the manufacturer can separately mold theclosure body30 as another, separate component. The top structure andbody30 may be molded from the same thermoplastic material or from different thermoplastic materials. Thelid40,webs160,anchor members152, andbody30 may have the same color and texture or may have different colors and/or textures.
• After separately molding theclosure body30 and the top structure (i.e., thelid40,webs160, andanchor members152 with protuberances164), the two components are assembled by mounting thelid40 on theclosure body30 so that thelid hinge shaft132 is received in a snap-fit engagement within the closurebody receiving channel82. Thelid40 is initially closed on theclosure body30 as shown inFIG. 5. In the initially closed position of thelid40, eachanchor member152 is disposed above the closure bodylower deck54 which defines the upwardly facing attachment surface. The lower, pointed edge of the anchor member attachingportion protuberance164 rests on the closure body attachment surface (i.e., the upwardly facing surface of the closure body lower deck54). The closure manufacturer can then weld theanchor members152 to thedeck54.
• A presently preferred method for welding theanchor members152 to the closure bodylower deck54 employs thermoplastic welding, and preferably thermoplastic welding as effected with ultrasonic energy. The triangularcross section protuberance164 on theattachment portion162 at the bottom of eachanchor member152 functions as an energy director for the ultrasonic energy. The ultrasonic energy can be applied with commercial ultrasonic welding equipment which may be of any suitable conventional or special design. Such ultrasonic welding equipment typically includes a suitable horn or engaging member for engaging the outwardly facing, exterior portions of theanchor members152 and for applying a force against theanchor members152 in a direction tending to urge theanchor members152 downwardly toward the closure body lowerdeck attachment surface54 at the same time that the ultrasonic equipment transfers ultrasonic energy into and through theanchor members152. The equipment operating energy, time, force, etc. depend, of course, on the size and mass of the closure top structure components that are to be welded as well as upon the type of thermoplastic material. The detailed design and operation of such ultrasonic welding equipment forms no part of the present invention.
• In one presently preferred embodiment, the ultrasonic welding of theanchor members152 to the closure bodylower deck54 is facilitated by providing thedeck54 with a textured surface. One such suitable textured surface can be provided by conventional etching of the relevant region of the mold steel through a conventional texture mask or plaque. In a preferred embodiment of the closure molded from polypropylene, the surface of the mold at theattachment surface54 is AISI (American Iron and Steel Institute) type 420 stainless steel with a hardness of 54-64 Rockwell c that has been (1) ferric chloride acid attached to a depth of 0.052 mm. through a plaque or mask designated MT 11050 as sold by Mold Tech (having an office at 279 East Lies Road, Carol Stream, Ill. 60188, U.S.A.), and (2) bead blasted to remove ash residue.
• During the welding of theanchor members152 to theclosure body deck54, the energy director protuberances164 (which may have a projection of about 0.55 mm. in a presently preferred embodiment) become softened and/or melted along with adjacent portions of theclosure body deck54. The softened or meltedprotuberances164 and the softened or melted portions of theclosure body deck54, along with any softened or melted portions of theanchor member152 adjacent the protuberances164) fuse and re-solidify after termination of the application of the ultrasonic energy and force. This effects a welding of the thermoplastic material (as schematically designated byreference number168 inFIG. 3).
• In the preferred embodiment, theenergy deflector protuberances164 project downwardly about 0.55 mm. After being ultrasonically welded, the melted and fusedprotuberances164 loose substantially all of their original height and shape so that the 0.55 mm. gap initially defined by theprotuberances164 is substantially eliminated and reduced to approximately 0 mm.
• The assembled, closed, and weldedclosure20 may then be shipped to an entity that fills bottles or other containers with a fluent product and then installs theclosures20 on the filled containers.
• With reference toFIGS. 15-16, it can be seen that thefrangible webs160 extend downwardly for a distance Y below the bottom edge of theclosure lid skirt124 where thewebs160 adjoin the inner top edge of theanchor member152. Thefrangible web160 spans the gap Y between the top of theanchor member152 and the bottom edge of theclosure lid skirt124.
• As best seen inFIG. 16, the radially inwardly facingvertical side153 of eachanchor member152 includes avertical rib170 which is a molded, unitary extension or part of theanchor member152 and which, in effect, merges with, and forms an extension from, thefrangible web160. As can be seen inFIG. 14, the bottom portion of theclosure lid skirt124 has anexternal rib174 which is molded unitary with, and extends from, the exterior surface of theclosure lid skirt124 so as to merge with the upper end of thefrangible web160. As can be seen inFIG. 16, within the vertical gap or space Y, theweb160 includes an enlarged orwider portion178 and a reduced width, or narrower,portion180. In a presently preferred embodiment of a polypropylene closure, the reducedwidth portion180 has a width of about 0.69 mm., a height above themember152 of about 0.25 mm., and a thickness of about0.25 mm.
• When the user wishes to open the closure, the user applies a generally upwardly directed force to the closure lid thumb lift128 (FIGS. 1 and 14). The application of a sufficiently large force will case thefrangible webs160 to break or rupture as illustrated inFIG. 17. Thefrangible webs160 break in the reducedwidth region180. Typically, the reducedwidth portion180 of thefrangible web160 will have some slight reduction in width (from W1 to W2 inFIG. 17) as the tensile stress along the length or height of thefrangible web160 causes some elongation prior to rupture.
• As shown inFIG. 17, when thefrangible webs160 rupture, a short length L, of the reducedwidth section180 typically will remain with thewider portion178 on thelid skirt124, and a short length L₂of the reducedwidth portion180 typically will remain with theanchor member152. In a presently preferred embodiment, after afrangible web160 breaks, the height L₂of the portion of the broken web projecting upwardly from theanchor member152 is about 0.2 mm., or less. Thus, the projection L₂of the reduced widthfrangible web portion180 on theanchor member152 is relatively small. If the opened closure is used to dispense a fluid for drinking, the user may place the user's lips around the closure body spout42 (FIG. 2) and against the surrounding deck portions of theclosure body30 without sensing any objectionable roughness from the brokenfrangible portions180 on theclosure body30 because such portions are so small and short.
• Before thelid40 is lifted for the first time to break thefrangible webs160, thefrangible webs160 provide an indication that thelid40 has not yet been opened. The user can readily see that thefrangible web160 are not ruptured because thefrangible webs160 span a relatively large gap having the height Y as shown inFIGS. 14-16. The gap Y between the bottom edge of thelid skirt124 and the top of theanchor member152 provides a good background, field of view, or visual environment in which to readily ascertain that thefrangible webs160 are not broken (or are broken).
• Further, the tamper-evident feature of theclosure20 can be enhanced by molding thelid40,frangible webs160, andanchor members152 from a suitable thermoplastic material that changes color after being subjected to a sufficient level of stress. In a preferred embodiment, polypropylene is used for molding the components, and during subsequent rupture of thefrangible webs160, thefrangible webs160 are subjected to sufficient stress to cause “stress whitening” in the region of the break. Thus, if the polypropylene that is used to mold thelid40,frangible webs160, andanchor members152 is tinted or colored so that it initially has a non-white hue, then there will be a lightening or whitening of the color of the material at, and adjacent, the broken surfaces of the frangible webs. This will further aid the user in ascertaining that thewebs160 have been broken.
• According to one aspect of the invention, the use of the relatively longfrangible webs160 to span the gap Y provides an enhanced tamper-evident feature regardless of how eachanchor member152 is affixed or connected to the underlyingclosure body deck54. Thus, it is not necessary, according to an optional form of the invention, to secure theanchor members152 to theclosure body deck54 with a thermoplastic weld. Instead, other connection means could be employed, such as, for example, a mechanical interference fit, staking, gluing, etc. If theanchor members152 are attached to theclosure body deck54 by means other than welding, then the closure components may be made from materials other than weldable thermoplastic materials.
• If desired, thefrangible webs160 could be configured to have orientations other than the generally vertical orientation illustrated inFIG. 16. For example, the radiallyinner sides153 of theanchor members152 could be located further radially outwardly (e.g., beyond the circumference of the closure lid40), and thefrangible webs160 could be inclined or angled radially outwardly at a substantial angle. Further, with reference toFIG. 15, eachfrangible web160 could be angled to the left or to the right instead of being located generally vertical as shown inFIG. 15.
• In yet another contemplated embodiment, thefrangible webs160 could be bi-injection-molded onto thelid40 andanchor members152 after thelid40 andanchor members152 are initially molded. That would permit thewebs160 to be molded from a different material having a different color and/or texture. This would make thefrangible webs160 even more visible to the user.
• The structure of the tamper-evident webs160, in relation to theclosure lid40 andanchor members152, accommodates ease of molding of thelid40,webs160, andanchor members152, and such molding does not require side action molding components or lifters. Further, theclosure20 functions well with various types of hinge structures, or with no hinge. Additionally, no separate shrink band is required to provide the tamper-evident function that is performed by thefrangible webs160. Opening thelid40 of theclosure20 does not require the user to break and remove a separate, discardable piece (e.g., shrink band). The tamper-evident function provided by thefrangible webs160 eliminates the need to provide other types of tamper-evident features that may be more expensive or more difficult to use.
• Furthermore, the tamper-evident structure provided by the frangible webs160 (in conjunction with theanchor members152 and the securement of theanchor members152 to the closure body30) accommodates the design of a closure which has high retention strength and which is very secure—especially when the design employs a weld of theanchor members152 to theclosure body30.
• Theclosure20 need not be made in two or more separate parts. For example, if desired, theentire closure20 could be molded as a single, unitary structure with an integral hinge system such as a snap-action hinge, tether hinge, or the like. The detailed design of such a hinge system forms no part of the present invention. Indeed, the present invention contemplates that thelid40 andclosure body30 could be provided as separate components without any hinge structure so that the lid would not remain attached to the closure body after the assembly is opened.
• When theclosure20 is in the full open condition as shown inFIG. 2, the user can tip or invert the package to facilitate the dispensing of fluent product under the influence of gravity. If thecontainer22 has a flexible wall or walls, thecontainer22 can be squeezed to further assist in dispensing the product. After the desired amount of product has been dispensed, the package can be turned back to its upright orientation, and the user can close thelid40. If the package is designed for “inverted” storage (such as if the closure includes a flexible, pressure-actuatable, self-sealing dispensing valve), the package may be left inverted at all times.
• It will also be appreciated that the closure system of the present invention need not be provided as a separate closure for a container. Theclosure body30 could instead be molded as a unitary part of thecontainer22. A container could be molded to have (1) an initially open bottom end, (2) a peripheral wall forming an upper end that defines a container top end opening, and (3) a unitary closure body portion extending radially inwardly from the container peripheral wall over the container top end opening so as to form a unitary part of the container top end and so as to define a unitary, top end closure body, including the spout42 (and optionally including a hinge and lid, if the body, hinge, and lid are to be part of a single, unitary structure). Then, the container could be filled with product through the open bottom end, and the open bottom end could be subsequently sealed closed by appropriate means, such as with thermally assisted deformation or with a separate bottom closure plug or bottom cap.
• It will also be appreciated that the closure system of the present invention may include other components, elements, or features. For example, the closure body30 (FIG. 3) could include an internal valve system. The valve could be, for example, a pressure-actuated, flexible, resilient slit valve. Such a valve has the configuration and operating characteristics of a commercially available valve design substantially as disclosed in the U.S. Pat. No. 5,676,289 with reference to thevalve46 disclosed in the U.S. Pat. No. 5,676,289. The operation of such a type of valve is further described with reference to the similar valve that is designated by reference number 3d in the U.S. Pat. No. 5,409,144. The descriptions of those patents are incorporated herein by reference thereto to the extent pertinent and to the extent not inconsistent herewith. The embodiment of the present invention shown inFIG. 7 herein could accommodate such a valve within theclosure body spout42 under the dispensingorifice44 and within, or in place of, thebaffle structure45. Such a valve could be held in place with a suitable retainer ring in snap-fit engagement with the closure body. Alternatively, such a valve could be secured with other means, such as bi-injection molding, insert molding, adhesive securement, crimping, swagging, or the like.
• It will be readily apparent from the foregoing detailed description of the invention and from the illustrations thereof that numerous variations and modifications may be effected without departing from the true spirit and scope of the novel concepts or principles of this invention.

Claims (19)

1. A tamper-evident closure system for a container that has an opening to the container interior, said closure system comprising:

a body that is either a separate structure for attaching to, and extending from, said container at said opening or is a unitary extension of said container at said opening, said body having

(1) at least one orifice for communicating with said container opening, and

(2) a thermoplastic attachment surface;

a lid adapted to be disposed on said body for accommodating lifting of said lid relative to said at least one orifice between (1) a closed position over said at least one orifice, and (2) an open position away from said at least one orifice;

an anchor member having a thermoplastic attaching portion for being welded to said body attachment surface when said lid is first in said closed position; and

at least one frangible web extending between said lid and said anchor member for initially connecting said anchor member with said lid for subsequently being broken when said lid is first lifted from said closed position.

2. The closure system in accordance withclaim 1 further including a welded connection between said attachment surface of said body and said attaching portion of said anchor member.

3. The closure system in accordance withclaim 1 in which there are two anchor members each having an attachment portion that includes an energy director having a triangular cross section for facilitating ultrasonic welding of the anchor member to said body attachment surface.

4. The closure system in accordance withclaim 1 in which

a portion of said lid has a skirt with a generally cylindrical exterior surface; and

each of said frangible webs has an upper portion molded as a unitary extension from said exterior surface of said lid skirt.

5. The closure system in accordance withclaim 1 in which each said frangible web has an upper wide portion and a lower narrow portion.

6. The closure system in accordance withclaim 1 in which

a portion of each said anchor member defines a radially inwardly facing surface;

each said frangible web has a lower portion molded as a unitary extension from said anchor member inwardly facing surface.

7. The closure system in accordance withclaim 1 in which

said closure system is a closure for an end of said container wherein the container end defines said container opening; and

said closure includes said body, said lid, said anchor member, and said at least one frangible member.

8. The closure system in accordance withclaim 7 in which

said closure is an article that is separate from said container; and

said body is attachable to said container end over said container opening.

9. The closure system in accordance withclaim 1 in which said lid, said anchor member, and said at least one frangible member are molded together from a thermoplastic material to form a unitary structure that is initially separate from said closure body.

10. A tamper-evident closure system for a container that has an opening to the container interior, said closure system comprising:

a body that is either a separate structure for attaching to, and extending from, said container at said opening or is a unitary extension of said container at said opening, said body having at least one orifice for communicating with said container opening, and a

a lid adapted to be disposed on said body for accommodating lifting of said lid relative to said at least one orifice between (1) a closed position over said at least one orifice, and (2) an open position away from said at least one orifice, said lid having a lower edge;

an anchor member non-removably fixed to said body when said lid is first in said closed position to define a vertical gap between said anchor member and said lid lower edge; and

at least one frangible web extending across said gap between said lid lower edge and said anchor member for initially connecting said anchor member with said lid for subsequently being broken when said lid is first lifted from said closed position.

11. The closure system in accordance withclaim 10 in which

a portion of said lid has a skirt with a generally cylindrical exterior surface; and

each said frangible web has an upper portion molded as a unitary extension from said exterior surface of said lid skirt.

12. The closure system in accordance withclaim 10 in which

each said frangible web has an upper wide portion and a lower narrow portion; and

the height of said vertical gap between said anchor member and said lid lower edge is greater than the width of said frangible web upper wide portion.

13. The closure system in accordance withclaim 10 in which

a portion of each said anchor member defines a radially inwardly facing surface; and

each said frangible web has a lower portion molded as a unitary extension from said anchor member inwardly facing surface.

14. The closure system in accordance withclaim 10 in which

said closure system is a closure for an end of said container wherein the container end defines said container opening; and

said closure includes said body, said lid, said anchor member, and said at least one frangible member.

15. The closure system in accordance withclaim 14 in which

said closure is an article that is separate from said container; and

said body is attachable to said container end over said container opening.

16. The closure system in accordance withclaim 10 in which said lid, said anchor member, and said at least one frangible member are molded together from a thermoplastic material to form a unitary structure that is initially separate from said closure body.

17. A method for making a tamper-evident closure system for a container that has an opening to the container interior, said method comprising the steps of:

(A) molding from thermoplastic material a body that

(1) is either a separate structure for attaching to, and extending from, said container at said opening or is a unitary extension of said container at said opening,

(2) has at least one orifice for communicating with said container opening, and

(3) has a thermoplastic attachment surface;

(B) molding from thermoplastic material a top structure comprising (1) a lid, (2) an anchor member that has an attaching portion, and (3) at least one frangible web that extends between, and is unitary with, said lid and said anchor member wherein said lid is adapted to be disposed on said body for accommodating lifting of said lid relative to said at least one orifice between (i) a closed position over said at least one orifice, and (ii) an open position away from said at least one orifice;

(C) mounting said top structure on said body with said lid disposed on said body in said closed position and with said anchor member attaching portion located adjacent said body thermoplastic attachment surface; and

(D) welding said anchor member attaching portion to said body thermoplastic attachment surface when said lid is first in said closed position to initially connect said anchor member with said lid so that said at least one frangible web can be subsequently broken when said lid is first lifted from said closed position.

18. The method in accordance withclaim 17 in which

step (B) includes molding said top structure to have said anchor member that has an attaching portion that includes an energy director having a triangular cross section for facilitating ultrasonic welding of the anchor member to said body attachment surface; and

step (D) includes utrasonically welding said anchor member to said body attachment surface.

19. The method in accordance withclaim 17 in which

step (B) includes molding a portion of said lid to have a skirt with a generally cylindrical exterior surface and a lower edge;

step (B) includes molding said anchor member to have an inwardly facing surface; and

step (B) includes molding each of said frangible webs to (1) have an upper portion molded as a unitary extension from said exterior surface of said lid skirt, (2) have a narrower lower portion molded as a unitary extension from said anchor member inwardly facing surface, and (3) have a length sufficient to create a vertical gap between said anchor member and said skirt lower edge wherein the height of said gap is greater than the width of said web upper portion.

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