Abstract:
A closure having a top wall and a skirt depending from a peripheral edge of said top wall. The closure includes an inner skirt depending from the top wall having at least one thread for helically attaching to a container neck. A deflection wall extends from the top wall having an inner diameter greater than a container neck. Extending from the top wall is a cutting device, defined by an axial cutter and a radial cutter for piercing a liner and cutting the liner about a circumference less than 360 degrees such that the liner is partially attached when the cutting process is completed.

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field of the Invention 
     The present invention relates generally to a double-shell closure. More particularly, the present invention relates to a double-shell closure having first and second intersecting triangles for cutting a container liner but which leaves a portion of the liner connected to the container rim such that the cut liner does not fall into the container and contact the product therein. 
     2. Description of the Related Art 
     Various closure designs are known which provide a piercing element in order to open a liner. However, the prior art patents fails to disclose a closure having a cutter formed of intersecting perpendicular triangles for opening a liner. 
     In view of currently known closures, it is preferable to have a closure which vents the internal product pressure when a container or package is initially opened while minimizing a consumer&#39;s exposure to the product dust produced from internal package pressure during initial package opening. 
     The present invention provides a double-shell closure for a container having a liner seal extending across a container rim sealing the container and allowing for build up of internal container pressure. The double-shell closure includes an outer skirt depending from a peripheral edge of a top wall and an inner skirt depending from the top wall. The inner skirt comprises at least one thread helically extending along an inner surface of the inner skirt. Extending along the outer surface of the inner skirt from the top wall downward are a plurality of strengthening ribs in a spaced apart relationship. In one exemplary configuration, the strengthening ribs are spaced apart about 11.25 degrees from each other but alternatively the strengthening ribs may be spaced apart in a plurality of configurations. 
     Along an upper portion of the outer shell are a plurality of knurls for aid in gripping the closure during removal and application of the closure to the container threads and when the closure is inverted for cutting the liner seal during initial opening of the container. 
     Depending from the lower edge portion of the closure outer skirt are diametrically opposed locking lugs. The locking lugs engage lugs on the container neck to provide a child resistance feature. The locking lugs may be substantially triangular in shape having an inner surface, a tapered deflection surface, and an engaging surface. During application of the closure to the container neck, each deflection surface cams against an inner surface of the container neck locking lug deflecting the closure lugs inward and causing ovalized flexing of the closure outer skirt. The strengthening ribs inhibit any flexing of the inner skirt. Once the closure lugs pass by the container lugs the closure returns to its circular shape and the engaging surface of the closure lug engages the container neck lug so that the closure may not back-off. The engaging surface prevents the closure from backing off of the container neck. Thus the diametrically opposed gripping ribs, each spaced about ninety degrees from the closure lugs, must be squeezed causing ovalized flexing of the closure and radially outward movement of the lugs allowing the closure lugs to move outward beyond the container neck lugs and the closure to be removed from the container neck. 
     Extending upwardly from the top wall and radially inset from the peripheral edge is a deflection wall. The upwardly extending wall has a diameter slightly larger than the outer diameter of a container neck thread. Also extending from the top wall is an cutter device comprising a first axial cutter and a second radial cutter. When the closure is inverted and placed over a container having a liner seal over the container rim, the axial cutter punctures the seal causing a the liner seal to tear. The radial cutter spreads the liner apart along the tear caused by the axial cutter and pushes the liner into the container. This action continues as the closure is rotated until a small portion of the uncut liner remains connected to the container rim. In other words the liner is not completely broken by the cutter but instead a portion is left intact to prevent the liner from completely falling into the container and thereby minimizing liner contact with the product in the container. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The aspects and advantages of the present invention will be better understood when the detailed description of the preferred embodiment is taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  shows a perspective view of the double-shell closure of the instant invention; 
         FIG. 2  shows a top view of the double-shell closure of  FIG. 1 ; 
         FIG. 3  shows a side sectional view of the double-shell closure of  FIG. 1 ; 
         FIG. 4  shows the closure of  FIG. 1  positioned on a container neck; 
         FIG. 5  shows a top view of the closure deflecting as it passes the engaging lugs of the container neck; 
         FIG. 6  shows a side view with cut-away portion of the closure of  FIG. 1  positioned on the container neck and cutting the liner seal; 
         FIG. 7  shows a side perspective view with a cut-away portion of a single shell closure embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention will now be described in conjunction with the drawings, referring initially to  FIGS. 1-4 , a closure  10  is shown. Although a double-shell closure is shown and described throughout the application, the closure of  FIG. 1  may be a single or double-shell closure as it is well within the scope of the present invention that a single shell closure may be substituted and utilized herewith, as depicted in  FIG. 7 . Thus the present invention is not limited to a double-shell closure. The closure  10  comprises a top wall  12  having a peripheral edge  14 . Depending from the peripheral edge  14  is an outer skirt  16  having diametrically opposed locking lugs  18  depending from a lower edge portion  20  of the outer skirt  16 . The lower edge portion  20  defines an opening wherein a container neck  72  may be disposed. Each of the locking lugs  18  may be substantially triangular in shape having an inner surface, a deflecting surface  22 , and an engaging surface  24 . As shown in  FIG. 2 , the deflection surfaces  22  are tapered. The tapered surface  22  allows the closure lug to pass on the inside of the container neck lugs  76  which are substantially diametrically opposed along the container neck  72  and provide a child resistance feature. The container lugs  76 , best seen in  FIGS. 5 and 6 , are merely exemplary and may be formed in many shapes and geometries as one of ordinary skill in the art will understand. As the closure  10  is placed on the container neck  72 , the deflecting surfaces  22  contact container lugs  76  and the closure  10  flexes into an ovalized form such that the locking lugs  18  pass along an inside surface of the container lugs  76 . Once the locking lugs  18  pass the container lugs  76 , the closure returns to its circular shape and the closure  10  cannot be backed off the container neck  72  since the engaging surfaces  24  contact the container lugs  76 . The child resistance feature must be overcome in order to remove the closure from the container neck  72 . 
     Also located along the outer surface of the outer skirt  16  are a plurality of gripping ribs  28 . The gripping ribs  28  are exemplified in  FIGS. 1 and 2  as being diametrically opposed and each spaced apart from the closure locking lugs  18  by about 90 degrees. The closure outer skirt  16  is of a thickness such that when an opposed squeezing force is applied to the gripping ribs  28 , the outer skirt  16  ovalizes as shown in  FIG. 5 . By squeezing the gripping ribs  28  and turning the closure  10  in a counterclockwise motion the locking lugs  18  are displaced radially outward a distance allowing them to pass the container lugs  76  thereby defeating the child resistance feature. Thus, the closure  10  may be removed from the container neck  72 . An inner skirt  30 , seen in  FIG. 3 , is inhibited from ovalizing by a plurality of ribs  34  spaced about the outer surface of the inner skirt  30  as will be discussed below. 
     Referring now to  FIG. 3 , as described above the closure  10  also comprises an inner skirt  30 . The inner skirt  30  is radially inset from the outer skirt  16  and has an inner surface and an outer surface. Helically extending along the inner surface of the inner skirt  30  is at least one thread  32 . The at least one thread  32  threadably engages a container neck  72  thread retaining the closure  10  on the container neck  72 . Extending from the outer surface of the inner skirt  30  are a plurality of strengthening ribs  34  which depend downwardly along the inner skirt from the top wall  12 . The strengthening ribs  34  also have a substantially rectangular shape and provide at least two advantages. First, the strengthening ribs  34  stabilize the inner skirt  30  with respect to the outer skirt  16  during cooling of the closure  10  as the closure is removed from the mold during manufacturing. Second, the strengthening ribs  34  inhibit ovalized flexing of the inner skirt during repeated opening and closing of the closure  10 . In one exemplary embodiment, there are  32  strengthening ribs  34  each spaced apart about 11.25 degrees however, there may be a plurality of various geometries and configurations positioned along the outer surface of the inner skirt  30 . 
     Extending upwardly from the top wall  12  is a deflecting wall  36 . The deflecting wall  36  has a diameter which is slightly larger than the maximum outer diameter of a container thread  74 . With this arrangement and as shown in  FIG. 6 , the closure  10  may be inverted and placed over the container rim to enclose the upper portion of the container neck  72 , including the container rim. The deflecting wall  36  provides at least two advantages. First, the deflecting wall  36  minimizes contact between the user and the product contained within the container. For example, when the liner seal covering the container mouth is pierced or broken internal pressure from within the container  70  is released. This may cause particulate or other product contained therein to spew from within the container  70  to outside the container  70 . The deflection wall  36  directs any product being ejected from the container  70  from the top wall  12  downward along the deflection wall  36  since the closure  10  is in an inverted position during opening, as shown in  FIG. 6 . As a result, contact between the user and the ejected product is minimized. A second advantage of the deflecting wall  36  is that the deflecting wall  36  centers the inverted closure  10  over the container neck  72  so that the cutter  40 , described below, may pierce and open the seal liner of the container  70  adjacent the container rim. 
     As shown in  FIGS. 1 and 2 , extending from the top wall of the closure  10  is a cutter  40 . The cutter  40  is defined by two projections, a first axial cutter  42  and a second radial cutter  44  and is located radially outward from the center of the top wall  12  and inset from the deflecting wall  36 . The first axial cutter  42  may have a triangular shape and, as exemplified in  FIG. 7 , the triangle defining the first axial cutter  42  is an isosceles triangle, however the triangle may alternatively be an equilateral triangle, as shown in  FIG. 1 . The top of the first cutter  42  forms a point for piercing a seal liner however the sides of the triangle are substantially flat, rather than sharpened, so that the seal liner tears as the closure  10  is rotated. 
     The second radial cutter  44  is also an isosceles triangle however, the radial cutter may alternatively be an equilateral triangle. The radial cutter  44  extends in a radial direction, substantially orthogonal to the axial cutter  42  and intersecting the axial cutter  42  at vertical centerlines. The radial cutter  44  has a height that is less than the height of the axial cutter  42 . The radial cutter  44  has at least two functions. First, the radial cutter  44  inhibits the seal liner from sealing around the axial cutter  42  when the seal liner is initially pierced. More specifically the spaces defined by about 90 degrees between the radial and axial cutter inhibit the seal liner from sealing against the axial cutter  42 . Therefore pressure is relieved from within the container immediately when the closure  10  is inverted and placed over the container neck  72 . Second, the radial cutter  44  spreads the seal liner where it is cut by the axial cutter  42  and pushes the seal liner downward into the container. 
     Extending radially inward from the deflecting wall  36  are feet  50 . As best exemplified in  FIG. 2 , the feet  50  extend radially inward from the deflecting wall  36  and are spaced apart about 90 degrees, however the feet  50  may be spaced apart in a plurality of configurations and at a plurality of arcuate distances. As depicted, the feet  50  are substantially rectangular in shape however various alternative shapes and tapers may be substituted. The feet  50  are raised from the top wall  12  of the closure  10  some distance and provide an air gap between the top wall of the closure  10  and the container rim when the seal liner is initially opened, as depicted in  FIG. 6 . The feet may be a uniform height, stepped, or tapered in order to provide the air gap. The air gap provided by feet  50  allows the container  70  to vent when the seal liner is pierced and any product which sprays from within the container  70  is directed into the deflecting wall and downward, away from a user. 
     In use, the closure  10  is threadably disposed on the container neck  72  as shown in  FIG. 4 . To remove the closure  10  from the container neck  72  a squeezing force is applied to each of the gripping ribs  28 . Upon application of sufficient force to the gripping ribs  28 , the closure  10  will flex into an ovalized shape and the closure lugs  18  will move radially outward beyond the container lugs  76 . When the engaging surface is spaced outward from the container neck lugs  76 , the child resistance feature is overcome and the closure  10  may be removed from the container neck  72 . 
     Upon removing the closure  10  from the container neck  72 , the closure  10  is inverted, the deflection wall  36  is aligned over the container rim, and the cutter  40  is pressed through a liner disposed over the container  70  opening, as shown in  FIG. 6 . As the cutter  40  pierces the liner, the feet  50  engage the container rim providing an air gap between the container rim and the top wall  12  of the closure  10 . Meanwhile, as the liner is pierced internal pressure from the container  70  may be released forcing particulate material upward to the closure top wall  12  and downward along the deflection wall  36  away from a user. 
     The foregoing detailed description is given primarily for clearness of understanding and no unnecessary limitations are to be understood therefrom for modifications will become obvious to those skilled in the art upon reading this disclosure and may be made without departing from the spirit of the invention and scope of the appended claims.