Abstract:
A lightweight hot-fill blow-molded plastic container ( 10, 110 ) having a sidewall ( 16 ) with a rigid grip portion ( 24, 124 ) and a flexible vacuum absorption portion ( 26, 126 ).

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to hot-fill blow-molded plastic containers, and more particularly, the present invention relates to hot-fill blow-molded plastic containers having opposed grips affording facile handling of the container by the consumer.  
         BACKGROUND OF THE INVENTION  
         [0002]    In the early 1990s, Graham Packaging Company pioneered the commercialization of hot-fill blow-molded plastic containers having sidewalls with elongate flex panels that incorporated grip structures. These containers are the subject of U.S. Pat. Nos. 5,392,937 and D.344,457. In the patented containers, the grip structure moves with the vacuum panel in response to vacuum induced inside the container in response to hot filling, capping and cooling of the container contents. While the patented Graham containers have been commercially successful, there is a desire to reduce the amount of plastic used in the manufacture of the container without sacrificing performance, to enhance ergonomic handling attributes, and to resist unwanted deformations in handling.  
         OBJECTIONS OF THE INVENTION  
         [0003]    With the foregoing in mind, an object of the present invention is to provide a light-weight hot-fillable blow-molded grip container which functions at least as well as the aforementioned Graham Packaging grip containers.  
           [0004]    Another object of the present invention is to provide a lightweight hot-fillable blow-molded plastic container having enhanced ergonomic handling qualities.  
           [0005]    Another object of the present invention is to provide a user-friendly, hot-fillable blow-molded plastic grip container that is sufficiently robust as to resist deformations that may occur in handling of the container during manufacture and after hot filling and capping.  
         SUMMARY OF THE INVENTION  
         [0006]    More specifically, the present invention provides a hot-fillable blow-molded plastic container having a sidewall with opposed label panels and intermediate panels each having a separate grip portion and a separate vacuum absorption portion. The grip portion has a wall portion inset into the container and extending chordally thereof to provide surfaces engageable by a user&#39;s finger and thumb when gripping the container. The grip wall portion is rigid to resist deflection when gripped and to resist flexure in response to normal vacuum conditions induced in the container in response to hot-fill processing. A vacuum absorption wall portion is located adjacent the grip wall portion and is separated therefrom by a rigid rib which extends between the label panels to rigidly interconnect them. Preferably, the grip portion is located superadjacent the vacuum absorption wall portion. Substantially the entire region between the label panels and the rib is occupied by the vacuum absorption wall portion. In one preferred embodiment, a smooth wall of a particular construction provides the entire vacuum absorption function. In another embodiment, a pair of vertically elongate vacuum panels separated by a post are provided to accommodate the requisite vacuum absorption. The rib that divides each intermediate panel into complementary configurations preferably extends diagonally thereacross, and is arcuate and of substantially the same radius of curvature as the label panels in order to provide a peripheral bumper between the label panels. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0007]    The foregoing and other objects, features and advantages of the present invention should become apparent from the following description when taken in conjunction with the accompanying drawings, in which:  
         [0008]    [0008]FIG. 1 is a side elevational view of one preferred embodiment of the present invention;  
         [0009]    [0009]FIG. 2 is a longitudinal sectional view taken on Line  2 - 2  of FIG. 1;  
         [0010]    [0010]FIG. 3 is a transverse sectional view taken on Line  3 - 3  of FIG. 1;  
         [0011]    [0011]FIG. 4 is a transverse sectional view taken on Line  4 - 4  of FIG. 1; and  
         [0012]    [0012]FIG. 5 is a side elevational view of another preferred embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0013]    Referring now to the drawings, FIG. 1 illustrates one preferred embodiment of a container  10  embodying the present invention. The container  10  has a conventional dome  12  and base  14 , both shown in phantom, and a sidewall  16  between the dome and base, shown in full. The sidewall  16  has opposed label panels  16   a  and  16   b  reinforced by a series of horizontally disposed grooves  18  and ribs  20  of conventional construction. The sidewall  16  has opposed intermediate panels  22   a  and  22   b  extending between the label panels  16   a  and  16   b , the front one of which is indicated at  16   a , and the rear one which is indicated at  16   b . The intermediate panel  22   a  has a separate rigid grip portion  24  and separate flexible vacuum absorption portion  26 . The intermediate panel  22   b  is of like construction and is disposed diametrically opposite the panel  22   a  shown in FIG. 1. See FIGS. 3 and 4,  
         [0014]    The grip portion  24  has a generally planar wall portion  24   a  which is inset into the container  10  from its generally cylindrical shape, and which extends chordally to provide opposed surfaces engageable by a user&#39;s fingers and thumb when gripping the container by placing the thumb in the obverse grip shown in FIG. 1 and the fingers in the reverse grip on the other side of the container  10 . The grip portion  24  has a pair of vertically spaced horizontally extending undulations  24   b ,  24   c  that rigidify the grip wall portion  24  and also provide an anti-slip function. The grip wall portion  24  is thereby formed to be rigid to resist deflection when gripped and to resist flexure in response to normal vacuum conditions induced in the container in response to hot filling, capping and cooling of the container contents.  
         [0015]    The grip portion  24  is of a generally irregular trapezoidal shape, having a base  28   a  located adjacent the rear label panel  16   b  and a frustum  28   b  located adjacent the front label panel  16   a . As best seen in FIG. 3, the front and rear label panels have the same radius of curvature to provide the container with a generally circular transverse cross section, although the invention has applicability to containers having generally rectangular or square transverse cross sectional configurations.  
         [0016]    Preferably, the grip wall portion  24  is located in proximity with the filled container center of gravity Cg. The configuration of the grip is such as to provide a target for the user to grip the container at an ergonomically desirable location for pouring from the container when filled.  
         [0017]    As best seen in FIG. 1, each intermediate panel  22   a  has a separate vacuum absorption wall portion  26  located immediately below the grip wall portion  24 . The grip wall portion  24  and vacuum absorption wall portion  26  are separated by a rigid rib  30  which extends between the front and rear label panels  16   a ,  16   b  for rigidly connecting the label panels for providing flexure resistance.  
         [0018]    The separate vacuum absorption wall panel  26  is located subjacent the grip wall portion  24 . The vacuum absorption wall portion  26  and grip wall portion  24  are thereby vertically aligned in the intermediate panels  22   a ,  22   b , and the vacuum absorption panel  26  occupies substantially the entire space between the front and rear label panels  16   a ,  16   b , the rib  30 , and the base  14  of the container  10 . The vacuum absorption wall panel  26  is designed and sized to provide substantially all of the normal hot-filled vacuum absorption required of the container sidewall.  
         [0019]    A preferred form of vacuum absorption wall construction is disclosed in PCT application published on Aug. 31, 2000 under publication No. WO 00/50309 filed in the name of David Melrose of Auckland, New Zealand. In the present invention the preferred vacuum absorption wall panel has an initiator section  26   a  for causing the wall portion to deflect inwardly in a controlled manner in response to vacuum induced inside the container as a result of filling, capping, and cooling. For a more complete description of the structure and function of a preferred vacuum absorption panel, reference is made to the aforementioned published PCT application, the disclosure which is incorporated by reference herein.  
         [0020]    In the embodiment of FIGS.  1 - 4 , the rib  30  extends diagonally across the intermediate panel and has a radius of curvature corresponding substantially to the front and rear label panels  16   a ,  16   b  to provide a robust lateral bumper that aids in preventing the container from being deformed in the course of handling during manufacture, filling and shipment to the ultimate consumer,  
         [0021]    Turning now to FIG. 5, another preferred embodiment  110  is provided utilizing the same general overall configuration as the aforementioned embodiment, but with some differences. For instance, the inset grip wall portion  124  has a pair of horizontally spaced, vertically elongated anti-slip ribs  124   b ,  124   c  extending outwardly in spaced parallel relation adjacent to the rear label panel  116   b . The vacuum absorption wall portion  126  below the grip includes a pair of vertically elongate flex panels  134 ,  136  which may be of conventional construction, or which may be in accordance with the teachings of the aforementioned PCT published application. The flex panels  134 , 136  extend vertically in spaced parallel relation subjacent the grip wall portion  124 . The flex panels  134 ,  136  are separated horizontally by a post  138  which extends vertically between and interconnects the rib  130  and container base  114 . The pair of flex panels are disposed in an arcuate array extending generally peripherally in substantial alignment with the arc of the rib and label panels. These vacuum absorption wall portions function to accommodate vacuum induced inside the container in response to hot filling, capping and cooling of the container contents.  
         [0022]    In both of the preferred embodiments, the center of gravity of the filled container is located in the region indicated generally at Cg in FIGS. 1 and 5. Both embodiments are designed to have a nominal filled capacity of 64 fluid ounces. The containers are designed to be filled hot, ie. at a temperature of at least about 185° F.  
         [0023]    By way of example, the comparison with a Graham patented grip container, such as disclosed in the aforementioned Graham patents, the container of the embodiment depicted in FIGS.  1 - 4  made of PET plastic weighs 75 grams, or less; whereas, the patented Graham container in production weighs 81 grams, or more.  
         [0024]    The containers are ergonomically friendly because the rigid grip wall portions are located at a desirable targeted lifting location and do not deflect in response to normal gripping pressure applied when lifting and pouring from a filled container. The rigidity enables all of the sidewall required vacuum accommodation to be accepted by the subjacent flexible vacuum absorption wall portions.  
         [0025]    While preferred embodiments of the present invention have been described in detail, various modifications, alterations and changes may be made without departing from the spirit and scope of the present invention as defined in the appended claims,