Grip dome container

An ergonomically friendly container (10, 30) having hot-fill capabilities is disclosed. The container (10, 30) has a pre-ovalized dome (14, 34) with grip surfaces (20, 21, 40, 42) that undergo controlled deformation for accommodating a portion of the volumetric shrinkage due to hot-filling, capping, and cooling. Preferably, anti-racking ribs (32a, 32b) extend laterally between the grip surfaces (20, 21, 40, 42) to prevent unwanted racking or twisting of the dome (14, 34) during vacuum absorption.

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 hotfilling, 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.
 A still further object of the present invention is to provide a plastic
 blow-molded container having a reinforced grip dome which resists
 distortion from forces caused by hot-fill processing.
 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'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.
 According to another aspect of the present invention, the peripheral recess
 of the dome includes a peripheral "anti-racking link", or rib, to prevent
 unwanted distortion of the dome. The rib permits a controlled amount of
 dome flexure so that the dome can accommodate a predetermined amount of
 volumetric shrinkage, but resists so-called "racking", or twisting, of the
 dome which would distort the appearance of the dome.

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 16 and 17 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', 14' connected at their ends to inwardly concave
 curved arcuate endwalls 14", 14".
 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'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 rip 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's
 finger, thumb, and hand may be placed, while the user'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'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.degree. F., capping, and cooling to ambient temperatures of about
 72.degree. 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'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', 20" and 21', 21" 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.
 Preferably, the container is provided with means to reinforce the dome to
 prevent unwanted distortion while permitting the required amount of vacuum
 absorption. The container 30, illustrated in FIGS. 9 and 10, is identical
 to the container 10 except for the peripheral reinforcement ribs 32a and
 32b. To this end, the container 30 has a finish 38 and a dome portion 34
 with an upper section 34a, an intermediate section 34b, and a lower
 section 34c superadjacent an upper label bumper 36. The intermediate dome
 section 34b has a pair of opposed grip surfaces 40 and 42 which are inset
 into the dome 34 and which afford engagement of the dome 34 between a
 user's thumb and finger. Peripheral recesses 44 and 46 are inset into the
 intermediate dome section 34b and interconnect the grip surfaces 40 and 42
 at their opposite ends.
 The peripheral reinforcement rib, or so-called "anti-racking link", 32a
 extends in the peripheral recess 44 laterally between the grip surfaces 40
 and 42, and the peripheral reinforcement rib, or so-called "anti-racking
 link", 32b extends in the peripheral recess 46 laterally between the grip
 surfaces 40 and 42 . Each rib, 32a and 32b is transversely elongate and
 extends to the opposite ends of the grip surfaces 40 and 42. As
 illustrated, the ribs 32a and 32b are outwardly concave, or C-shaped, in
 vertical cross-section and are located on the innermost portions of
 peripheral recess 44 and 46. The opposed ribs 32a and 32b cooperate to
 reinforce the dome 34 and prevent unwanted "racking", or twisting, of the
 dome 34 as might occur during certain vacuum absorption conditions of the
 dome 34. Thus, the ribs 32a and 32b allow the grippable dome 34 to
 accommodate a pre-determined amount of vacuum in a controlled manner,
 while preventing the bell-shaped dome 34 from becoming distorted. If
 conditions conducive to dome racking are not encountered, the use of the
 ribs, or anti-racking links, 32a and 32b can be eliminated.
 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 domes 14 and 34, the grip surfaces 20,
 21, 40 and 42 are able to be located at a point slightly higher than the
 filled center of gravity of the container 10 or 30, making the containers
 10 and 30 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 configurations 14 and 34 not only provide ergonomically-desirable
 lift and pour capabilities, but also provide the containers 10 and 30 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 containers 10 and 30 are 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 containers
 10 and 30 would still retain their 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.