Abstract:
An ergonomically friendly container having hot-fill capabilities is disclosed. The container has a pre-ovalized dome with grip surfaces that undergo controlled deformation for accommodating a portion of the volumetric shrinkage due to hot filling, capping and cooling.

Description:
FIELD OF THE INVENTION 
     The present invention relates to grippable blow-molded plastic containers, and more particularly, the present invention relates to hot-fillable blow-molded plastic containers having grip features that facilitate lifting and pouring. 
     BACKGROUND OF THE INVENTION 
     The conventional hot-fillable blow-molded PET container is generally characterized by a body portion having a series of vertically elongate vacuum flex panels disposed in spaced relation about its periphery for accommodating volumetric shrinkage in the container due to the vacuum created after the container has been hot-filled with liquid, capped and cooled to ambient temperature. The upper portion, or dome, of the container has been generally characterized by a circular cross-section having a waist. Some people use the waist to grip the container for pouring with one hand, but this is not satisfactory because the waist is too large to be gripped readily. A stepped dome is easier to grip, but does not facilitate pouring from the container because it is too far from the filled container center of gravity. 
     At present, it has been necessary to make the vacuum flex panels relatively long in order to accommodate the amount of vacuum induced shrinkage required to provide a commercially satisfactory container. Examples of such containers are disclosed in the following U.S. patents owned by the assignee of the present application: D366,416; D366,417; D366,831. 
     Efforts have been made to incorporate grips in hot-fillable containers to afford both ease of pouring and to accommodate the vacuum induced shrinkage of the container. An example of such a container manufactured by the assignee of the present application is disclosed in the following U.S. Pat. Nos. D344,457; 5,392,937; and 5,598,941. 
     The aforementioned containers have certain advantages and certain disadvantages. The conventional vacuum panel has the advantage of enabling relatively large size containers with large labelable areas to be produced; however, it has disadvantage of making such containers difficult to handle. Grip panel containers, on the other hand, have the advantage of providing relatively easy pourability for certain sizes; however, grip panels are difficult to provide in large size containers, and labelable areas are reduced. It is apparent, therefore, that there is a need for a blow-molded plastic container that provides both the ready gripability and pourability afforded by grip-panel containers while providing large labelable areas and avoiding the limitations associated with conventional vacuum-panel containers. 
     OBJECTS OF THE INVENTION 
     With the foregoing in mind, a primary object of the present invention is to provide a novel grippable container that provides facile gripping and pouring of its contents. 
     Another object of the present invention is to provide an improved hot-fillable blow-molded container which utilizes conventional vacuum panels in combination with a specially configured grip dome that cooperates with the vacuum panels to accommodate the requisite vacuum induced shrinkage of the container due to hot-filling, capping and cooling. 
     Another object of the present invention is to provide a container having grips formed in its dome to facilitate gripping and pouring of contents from the container while utilizing shorter conventional vacuum panels to thereby provide the container with an ergonomically-improved lifting and pouring balance. 
     SUMMARY OF THE INVENTION 
     More specifically, the present invention provides a blow-molded grippable container having a body portion with a series of vacuum panels and a dome portion which incorporates grip panels to facilitate gripping and pouring of contents from the container. In the illustrated embodiment, the dome portion has a non-circular transverse cross-section with opposed elongate sides in which are provided an opposed pair of grip surfaces connected at their opposite ends by a recess extending around opposed peripheral portions of the dome. The grip surfaces are adapted to be engaged between a finger and thumb of the user while the user&#39;s hand portion is engaged in the recess. The dome is configured to enable the opposed grip surfaces to flex toward one another to accommodate a predetermined amount of volumetric shrinkage due to hot-filling, capping and cooling. The vacuum flex panels provided in the body portion below the dome accommodate another predetermined amount of volumetric shrinkage. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     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 accompanied drawings, in which: 
     FIG. 1 is a side elevational view of a grippable container embodying the present invention; 
     FIG. 2 is a front elevational view of the container illustrated in FIG. 1 but with portions broken away; 
     FIG. 3 is a transverse sectional view taken along line 3--3 of FIG. 1; 
     FIG. 4 is a transverse sectional view taken along line 4--4 of FIG. 1; 
     FIG. 5 is a transverse sectional view taken along line 5--5 of FIG. 1; 
     FIG. 6 is a transverse sectional view taken along line 6--6 of FIG. 1; 
     FIG. 7 is a transverse sectional view taken along line 7--7 of FIG. 1; and 
     FIG. 8 is a transverse sectional view taken along line 8--8 of FIG. 1. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings, FIG. 1 illustrates a grippable container 10 which is particularly suited for hot fill applications. As best seen therein, the container 10 has a body portion 11, which may be of tubular cross section, such as cylindrical or rectangular, having a plurality of circumferentially spaced vacuum panels, such as the panels 12 and 13. The body portion 11 of the container 10 has an upper label bumper 16 and a lower label bumper 17 both of which extend continuously about the periphery of the body portion 11. The vacuum panels 12 and 13 are located between the label bumpers 12 and 13 for accommodating vacuum induced shrinkage resulting from liquid contraction due to the hot fill process. Thus, the term vacuum induced volumetric shrinkage as used herein refers to such shrinkage, and not to inherent thermally-induced volumetric shrinkage. The vacuum panels 12 and 13 also include customary label support regions 12a and 13a for supporting a label (not shown) in the region between the upper and lower label bumpers 16 and 17 as well known in the art. A suitable base 19 is provided below the lower label bumper 17. The base 19 is of conventional construction having appropriate reinforcing ribs, such as radial ribs, to provide the desired stiffness and anti-everting capabilities preferred for a hot fill container, as well known in the art. 
     The container 10 has a dome portion 14 superposed on the body portion 11. The dome portion 14 has a conventional flanged finish 15 with threads (not shown) adapted to receive a cap. The dome portion 14 has an upper section 14a, an intermediate section 14b, and a lower section 14c superadjacent the upper label bumper 16. The dome 14 lies within a cylindrical plane extending upwardly tangent to the upper label bumper 16. 
     As best seen in FIG. 3, the upper dome section 14a has a non-circular transverse cross-section that diverges outwardly and downwardly from the finish 15. Preferably, both the upper and intermediate dome sections 14a and 14b, respectively, have elliptical transverse cross-sections in a plane perpendicular to a longitudinal axis A--A extending vertically through the center of the container 10. The lower dome section 14c also has an elliptical cross section that flares circularly outwardly and downwardly to merge with the circular upper label bumper 16. 
     As also seen in FIG. 3, the major, or long, axis B--B of the elliptical sections of the dome 14 extends front to rear of the container 10, and the minor, or short, axis C--C of the dome 14 extends side to side of the container 10. The dome 14 has an opposed pair of inwardly concave, curved elongate sidewalls 14&#39;, 14&#39; connected at their ends to inwardly concave curved arcuate endwalls 14&#34;, 14&#34;. 
     Referring to FIG. 2, the upper section 14a of the dome 14 has an inwardly concave vertical cross-section providing a chamber having a generally bulbous concave configuration. The upper dome section 14a terminates in a continuous curved undulating brow rib 25 having an opposed pair of flattened apogees 25a and 25b located in the dome sidewalls, and having an opposed pair of perigees 25c and 25d located in the dome endwalls. Anti-slip ledges, or shoulders 26a and 26b are provided above each apogee, such as apogee 25a, for purposes to be described. 
     The intermediate dome section 14b has a pair of opposed transversely elongate grip surfaces 20 and 21 which are inset deeply into the dome 14 below the brow rib apogees 25a and 25b, respectively, and are preferably outwardly concave to afford engagement between a user&#39;s thumb and finger, such as the index finger. The grip surfaces 20 and 21 extend equidistantly on opposite sides of the container longitudinal axis A--A and are located above, but adjacent to, the upper label bumper 16. Recesses 23 and 24, which are less deeply inset into the dome 14 than the grip surfaces 20 and 21, interconnect the grip surfaces 20 and 21 at their opposite ends. The grip surfaces 20 and 21 cooperate with the peripheral recesses 23 and 24 to enable the user to place his or her index finger and thumb on the grip surfaces 20 and 21 and the connecting hand region in either the recess 23, or the recess 24, to lift and pour from either the front or back of the container 10. The brow rib 25 above the grip surfaces 20 and 21 and recesses 23 and 24 cooperates with the anti-slip ledges 26a, 26b to provide a surface region against which the upper sides of the user&#39;s finger, thumb, and hand may be placed, while the user&#39;s palm engages the generally circular surface of the lower dome section 14c when manipulating the container 10. 
     In the illustrated embodiment (drawn in FIGS. 1 and 2 to approximately half full scale) the container 10 has a filled nominal capacity of 96 ozs. The capacity of the body portion 11 up to the upper label bumper 16, is about 56 ozs. The capacity of the dome between the upper label bumper 16 and the top of the finish 15 is about 40 ozs. As a result, the dome portion provides approximately 41 percent of the total nominal volumetric capacity of the container 10. By way of comparison with a stock 96 oz circular bell cross-section conventional vacuum panel container of Applicant&#39;s manufacture, the bell volume constitutes about 30% of the total container filled volume. 
     The filled center of gravity of the container (C.G.) is located about 125 mm of the overall height of the container 10 which is 292 mm measured from a base support datum, such as a flat surface on which the container is placed. Preferably, the filled center of gravity is located in a range of about 40% to about 45% of the overall container height, or length, and the grip surfaces 20, 21 are located upwardly adjacent the filled center of gravity within about 55% to about 65%, and more preferably about 60% of the overall container height. Desirably, the grip surfaces 20 and 21 are separated by a distance in a range of about 75 to about 90 mm across the minor axis C--C of the elliptical cross-section illustrated. The grip surfaces have an overall length of about 70 mm, and the shortest peripheral distance from the center of one grip surface 20 to the center of the opposite grip surface 21 is about 175 mm. The aforedescribed dimensional and surface configurations cooperate to provide a container which can be lifted and its contents poured in a facile manner. 
     The container 10 is particularly suited for hot-fill applications. Under conditions of hot-filling with liquid at a temperature approaching 200° F., capping, and cooling to ambient temperatures of about 72° F., the body portion vacuum panels, such the panels 12 and 13, flex inwardly as well known in the art to accommodate volumetric shrinkage. However, unlike conventional hot fill containers, in the container 10 of the present invention, the vacuum panels do not accommodate all of the container&#39;s volumetric shrinkage. Rather, in the container of the present invention, the dome 14 accommodates approximately 5% of the total volumetric shrinkage of the container 10 due to hot fill, capping, and cooling. The balance is accommodated by the conventional vacuum panels, such as panels 12 and 13. 
     In the present invention, the grip surfaces 20 and 21 are mounted to flex inwardly toward one another by means of flexible webs to accommodate volumetric shrinkage in the dome 14. Such flexural movement may be seen in FIG. 5 which schematically illustrates in phantom lines the inward deflection of the grip surfaces 20 and 21 in their inwardly-flexed positions. The geometry of the dome tends to afford flexure primarily from side to side to provide the requisite grip surface movement. Flexure occurs about two pairs of vertical hinge lines located generally in the regions 20&#39;, 20&#34; and 21&#39;, 21&#34; shown in FIGS. 1 and 5. Shrinkage is also facilitated to some extent by the inwardly concave peripheral hinge web region 28 (FIG. 2) located adjacent the juncture of the intermediate dome section 14b and lower dome section 14c in conjunction with the overlying brow rib 25. As seen in FIG. 2, the hinge web 28 is inwardly convex relative to upper and lower spaced lines of inflection 28a and 28b, respectively, which extend peripherally around the dome 14. 
     As a result of dome vacuum absorption, the vacuum panels in the body portion 11 are shorter in vertical height than conventional flex panels, since they do not provide the sole means for vacuum absorption. By reducing the height of the vacuum panels, and providing a predetermined measure of vacuum absorption in the dome 14, the grip surfaces 20 and 21 are able to be located at a point slightly higher than the filled center of gravity of the container 10, making the container 10 easy to grasp, lift, and pour, as contrasted with conventional cylindrical vacuum flex panel containers which simply have circular dome cross-sectional configurations with concomitant ergonomic limitations. 
     The dome configuration 14 not only provides ergonomically-desirable lift and pour capabilities, but also provides the container 10 with excellent top loading capabilities. The shortened height of the flex panels reduces the height of the label, but still provides a label area larger in size than on a comparable sidewall grip container. The larger dome enables customer designs and logotypes to be molded prominently in the dome. 
     Preferably, the container 10 is blow molded of PET plastic in a heat-set mold utilizing commercially available blow-molding equipment. 
     If the hot fill capabilities are not required, the body portion flex panels may be eliminated, and other plastic materials may be used. The container 10 would still retain its ergonomic lift and pour capabilities. 
     While a preferred embodiment of the present invention has been described in detail, various modifications, alterations and changes may be made without departing from the spirit and scope of the invention as defined in the appended claims.