Patent Publication Number: US-7581652-B2

Title: Tamper-indicating package, and a closure and container for such a package

Description:
The present disclosure is directed to a tamper-indicating package, and to a closure and container for such a package, in which the closure and container are constructed such that the tamper-indicating mechanism is activated before loss of sealing engagement between the closure and the container neck finish. 
     BACKGROUND AND SUMMARY OF THE DISCLOSURE 
     Many aseptic-fill packages, such as packages for dairy products, are provided with a foil seal over the end of the container neck finish before the closure is applied to the neck finish. This foil seal functions both to seal the package during shipment, storage and handling, and to provide indication that the package has been opened when the foil seal has been ruptured or removed. However, there is a desire to eliminate the cost associated with provision of this foil seal and the inconvenience of requiring removal of the foil seal by the consumer. The present disclosure is directed to a tamper-indicating package, and to a closure and a container for such a package, in which the closure and the container are constructed such that a tamper-indicating mechanism on the closure is activated before loss of sealing engagement between the closure and the container neck finish. 
     The present disclosure embodies a number of aspects that can be implemented separately from or in combination with each other. 
     A tamper-indicating package in accordance with one aspect of the present disclosure includes a container having a neck finish with an open end, at least one external thread segment, and first and second sets of angularly spaced ratchet teeth in diametrically opposed arrays spaced from the open end of the neck finish. A closure has a base wall with an annular skirt and at least one internal thread segment on the skirt for engagement with the external thread segment on the container neck finish to secure the closure to the container. A circumferential array of angularly spaced flexible resilient ratchet wings extend counterclockwise from an inner surface of the tamper band at an angle to such inner surface. A flexible resilient sealing liner is provided on the base wall within the skirt, and has an annular surface that faces radially outwardly toward the skirt and axially away from the base wall. The ratchet wings are resiliently flexed by the ratchet teeth radially outwardly toward the tamper band during clockwise application of the closure to the container neck finish, and abut clockwise-oriented abutment faces on the ratchet teeth to resist counterclockwise unthreading of the closure from the neck finish so that removal of the closure from the neck finish frangibly separates the tamper band from the skirt. Resilient engagement of the liner surface with the open end of the container neck finish is such that the tamper band is separated from the skirt before loss of sealing engagement between the liner and the open end of the neck finish. 
     The open end of the neck finish preferably has a radially inwardly extending trim flange, which may be flexible, resilient and deformed axially inwardly by engagement with the liner surface. Resilient engagement of the liner surface with the trim flange is such that the tamper band is separated from the skirt before loss of sealing engagement between the liner and the trim flange. The ratchet wings preferably extend from an inside surface of the tamper band onto an inside surface of the closure skirt and frangibly connect the tamper band to the skirt. Each ratchet tooth of each set on the container neck finish preferably is diametrically opposed to an associated ratchet tooth of the opposing set, such that all ratchet teeth are simultaneously engaged by ratchet wings on the closure skirt. The flexible resilient liner preferably includes barrier material resistant to migration of gases, water vapor and/or flavorants through the liner. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure, together with additional objects, features, advantages and aspects thereof, will best be understood from the following description, the appended claims and the accompanying drawings, in which: 
         FIG. 1  is a fragmentary sectional view of a tamper-indicating package in accordance with an exemplary embodiment of the present disclosure; 
         FIG. 2  is a sectional view taken substantially along the line  2 - 2  of  FIG. 1 ; 
         FIG. 3  is a fragmentary elevational view of the container in the package of  FIGS. 1 and 2 ; 
         FIG. 4  is a top plan view of the container illustrated in  FIG. 3 ; 
         FIG. 5  is a fragmentary sectional view taken substantially along the line  5 - 5  in  FIG. 4 ; 
         FIG. 5A  is a fragmentary sectional view of the portion of  FIG. 5  within the area  5 A; 
         FIG. 6  is a fragmentary sectional view of the portion of  FIG. 4  within the area  6 ; 
         FIG. 7  is a fragmentary sectional view on an enlarged scale of the portion of  FIG. 6  within the area  7 ; 
         FIG. 8  is a fragmentary sectional view of the closure in the package of  FIGS. 1 and 2 ; 
         FIG. 9  is a fragmentary sectional view of a closure in accordance with another exemplary embodiment of the disclosure; 
         FIG. 10  is a partially sectioned elevational view of the shell in the closure of  FIG. 8 ; 
         FIG. 11  is a bottom plan view of the closure shell in  FIG. 10 ; 
         FIG. 12  is a sectional view taken substantially along the line  12 - 12  in  FIG. 10 ; 
         FIGS. 13 and 14  are fragmentary sectional views taken substantially along the lines  13 - 13  and  14 - 14  in  FIG. 11 ; and 
         FIG. 15  is a fragmentary sectional view taken substantially along the line  15 - 15  in  FIG. 12 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The disclosure of U.S. Pat. No. 6,533,136 is incorporated herein by reference. 
       FIGS. 1-2  illustrate a package  20  in accordance with an exemplary embodiment of the present disclosure. Package  20  includes a closure  22  applied to the neck finish  24  of a container  26 . Container  26  is illustrated in greater detail in  FIGS. 3-7 . Neck finish  24 , which typically is cylindrical, has one or more external thread segments  28 . First and second sets  30 , 32  of angularly spaced ratchet teeth  34  are in diametrically opposed arrays on neck finish  24  on a side of thread segments  28  remote from the open upper end of the neck finish. (Directional words such as “upper” and “lower” are employed by way of description and not limitation with respect to the upright orientation of the package, container and closure illustrated in  FIGS. 1 ,  3  and  10 , for example. Directional words such as “diametric” or “circumferential” are employed by way of description and not limitation with respect to the axis of the container neck finish and/or the closure skirt as appropriate. The term “thread segment” is employed in its usual broad sense to include both partial and full helical threads, and both continuous and interrupted threads.) Ratchet teeth  34  extend radially outwardly from an external ledge  33 , which preferably extends entirely around the neck finish. Ledge  33  and ratchet teeth  34  may be solid, as shown, or hollow. Each ratchet tooth  34  has a counterclockwise-facing cam surface  35  and a clockwise-facing abutment surface  36 . Ratchet teeth  34  may be identical, but preferably are non-identical to facilitate removal of container neck finish  24  from its forming mold. 
     Container  26 , including neck finish  24 , preferably is formed in an extrusion blow molding operation, as described for example in detail in above-referenced U.S. Pat. No. 6,533,136. During such container manufacture, a trim flange  38  is formed at the open end of the container neck finish during a post-mold trimming operation by means of a suitable knife blade or the like to separate the container neck finish from an integrally formed moil or another container. This trimming operation forms a trimmed surface  40  ( FIG. 5A ) on which there is no vestige caused by mold mismatch or the like during the molding operation. Trimmed surface  40 , which is annular ( FIG. 4 ) and extends around the open end of the container neck finish, may be in a plane perpendicular to the axis of the container neck finish as illustrated in  FIG. 5A , or may be a conical surface that extends either upwardly or downwardly with respect to the container neck finish, particularly after the neck finish and trim flange have cooled after the trimming operation. By way of example only, trimmed surface  40  may nominally be perpendicular to the axis of the neck finish as noted, and undersurface  41  ( FIG. 5A ) of trim flange  38  may be at a nominal angle of 45° to the neck finish axis. Container  26  may be of any suitable material, such as a polyethylene. Depending upon the geometry of trim flange  38 , the trim flange can be relatively rigid, or can be flexible and resilient. 
     Closure  22  is illustrated in detail in FIGS.  8  and  10 - 15 . Closure  22  includes a one-piece shell  42  of compression molded or injection molded plastic construction, such as polypropylene for example. Shell  42  has a base wall  44  and an annular skirt  46 . Skirt  46  is illustrated as extending from the periphery of base wall  44  in the exemplary embodiment of the disclosure. However, in other embodiments of the disclosure, there may be an additional skirt disposed radially outwardly of skirt  46  to match the sidewall contour of the container to which the closure will be applied. One or more internal thread segments  48  are provided on the inside surface of skirt  46 . A tamper band  50  is frangibly connected to skirt  46  of closure shell  42 . In shell  42  as molded ( FIGS. 10-15 ), tamper band  50  preferably forms an integral axial extension from the end of skirt  46  remote from base wall  44 . Tamper band  50  separates from skirt  46 , as will be described, to indicate that the package has been opened. In the exemplary embodiment of the disclosure, this band separation is complete, in that band  50  completely separates from skirt  46 . However, tamper band separation could be partial separation, as described for example in U.S. Pat. Nos. 4,432,461, 5,295,600 or 6,053,344, and still be within the scope of the present disclosure. 
     A circumferential array of angularly spaced flexible resilient ratchet wings  52  extend from the inner surface of tamper band  50 . Ratchet wings  52  preferably are nominally flat as molded and extend counterclockwise at an angle to the inner surface of band  50  as viewed from above (or clockwise as viewed from below in  FIGS. 11 and 12 ). Ratchet wings  52  preferably are at equal angular spacing around the inner surface of tamper band  50 . In the illustrated exemplary embodiment of the disclosure, there are eighteen ratchet wings  52  at equal angular spacings of 20° around the inside surface of tamper band  50 , and the abutment spaces  36  ( FIGS. 4 ,  6  and  7 ) of ratchet teeth  34  preferably are at equal angular spacings of 20°. Each ratchet wing  52  preferably extends axially from the inner surface of band  50  onto the inner surface of skirt  46 . As best seen in  FIG. 8 , skirt  46  has an internal ledge  53 . Ratchet wings integrally extend along the inside surface of band  50  and skirt  46 , and are integrally joined to ledge  53 . Ratchet wings  52  preferably do not extend all of the way to the free edge of band  50 . Skirt  46  preferably is scored along the line  54  in  FIGS. 1 and 8 , substantially at the location of section line  12 - 12  in  FIG. 10 , following the shell molding operation. This score extends through the integral connection of band  50  to skirt  46 , so that band  50  is frangibly connected to skirt  46  by the several ratchet wings  52 . Extension of ratchet wings into skirt  46  enhances the stability of the ratchet wings, and the use of the ratchet wings as the frangible connection to skirt  46  eliminates the need for separately molded leaders. As an alternative, band  50  may be separate from skirt  46  and connected to skirt  46  by ratchet wings  52  as molded. 
     After molding closure shell  42 , and either before or after scoring along the line  54  as preferred, a liner  56  is provided on the inside or undersurface of closure base wall  44 . Liner  56  is of flexible resilient construction, and may be provided on closure base wall  44  in a compression molding or other suitable liner forming operation. Liner  56  has a sealing surface  58  that faces radially outwardly toward skirt  46  and axially away from base wall  44 . Surface  58  in the embodiment of  FIGS. 1 and 8  is a conical surface, for example having an angle of about 62° to the axis of skirt  46 .  FIG. 9  illustrates another exemplary embodiment in which the sealing surface  58   a  of liner  56   a  is at an angle of about 86° to the axis of the closure skirt. Liner  56  (or  56   a ) preferably includes a barrier material resistant to migration of gases, water vapor and/or flavorants through the liner. Liner  56  (or  56   a ) may, for example, be provided in accordance with the disclosure of U.S. Pat. No. 6,371,318 or U.S. Pat. No. 6,399,170. Liner  56  or  56   a  extends along the entire undersurface of closure base used  44  within surface  58 , and preferably slightly radially outward from surface  58  as shown. 
     Closure  22  is applied to container neck finish  24  by threading the closure onto the container neck finish in a clockwise direction as viewed from above. Ratchet wings  52  on closure  22  engage cam surfaces  35  on ratchet teeth  34 , and are resiliently flexed by the ratchet teeth radially outwardly toward tamper band  50  and closure skirt  46  during such clockwise application of the closure to the neck finish. Whereas ratchet wings  52  preferably are flat as molded, and preferably are at substantially identical angles to the inside surface of tamper band  50  as molded, the ratchet wings may bend to non-flat configurations and/or to non-identical angles to the tamper band during application to the container neck finish. The axial spacings and dimensions between container thread segments  28  and ratchet teeth  34 , and between closure thread segments  48  and ratchet wings  52 , preferably are such that the thread segments engage each other as the closure is applied to the container before the ratchet wings engage the ratchet teeth. This helps assemble the closure onto the container in automatic capping equipment. Full application of the closure to the container neck finish brings trimmed surface  40  of neck finish trim flange  38  into opposed or abutting engagement with sealing surface  58  of liner  56  (or sealing surface  58   a  of liner  56   a  in  FIG. 9 ). The resiliency of liner  56  is such that trim flange  38  compresses the liner. The trim flange  38  may be such that the trim flange is resiliently flexed inwardly (with respect to the container) by engagement with liner  56  during application of the closure. 
     When closure  22  thereafter is rotated in the counterclockwise or removal direction with respect to container neck finish  24 , ratchet wings  52  are brought into engagement with abutment faces  36  of ratchet teeth  34 , as illustrated in  FIG. 2 . A preferred equal angular spacing of abutment faces  36  and ratchet wings  52  ensures that all of the abutment faces  36  are simultaneously engaged by ratchet wings  52 , as shown in  FIG. 2 . This simultaneous engagement facilitates rupture or frangible separation of tamper band  50  from closure skirt  46 . In accordance with the present disclosure, the resiliency of liner  56  (or  56   a ) and/or trim flange  38  is such that tamper band  50  is separated from closure skirt  46  before the loss of sealing engagement between liner  56  (or  56   a ) and trim flange  38 . 
     There thus have been disclosed a tamper-indicating package, and a closure and container for such a package, that fully satisfy all of the objects and aims previously set forth. The disclosure has been presented in connection with several exemplary embodiments, and a number of additional modifications and variations have been discussed. Other modifications and variations readily will suggest themselves to persons of ordinary skill in the art in view of the foregoing discussion. The disclosure is intended to embrace all such modifications and variations as fall within the spirit and broad scope of the appended claims.