CROSS-REFERENCE TO RELATED APPLICATION

[0001] Benefit is claimed of U.S. Patent Application No. 62/201,301, filed August 5, 2015, and entitled "Bowtie Hinges", the disclosure of which is incorporated by reference herein in its entirety as if set forth at length.

BACKGROUND

[0002] The invention relates to packaging. More particularly, the invention relates to living hinges for molded package closures.

[0003] A well-developed art exists in molded plastic living hinges. Key examples involve consumer goods packaging such as caps for bottles, dispensing tubes, jars, tubs and the like. Exemplary situations involve a closure formed as the unitary molding of a base for securing to a container body, a closure member (e.g., a cover) for opening and closing relative to the base, and a hinge connecting the base and the closure member to guide movement between closed and open conditions. A variety of such closures have been proposed. One example of a snap hinge closure is found in US Patent No. 5143234 of Lohrman et al.

[0004] PCT/US2011/053858 discloses yet further living hinge configurations.

SUMMARY

[0005] One aspect of the disclosure involves a system comprising the unitarily molded single-piece combination of: a first portion; a living hinge; and a second portion coupled by the living hinge to the first portion and shiftable between a first condition and second condition via rotation about the living hinge. The living hinge comprises a first end at the first portion and a second end at the second portion. Between the first end and the second end, the hinge comprises: a central portion; first and second lateral portions; a first face; and a second face, at least one of the first face and the second face bearing a transversely elongate rib.

[0006] In one or more embodiments, the first condition is an open condition and the second condition is a closed condition. The rib is along the second face. The second face is an outboard face in the closed condition.

[0007] In one or more embodiments, the first face has a channel opposite the rib.

[0008] In one or more embodiments, in the first condition the lateral portions are angled downwardly relative to the central portion wherein downward corresponds to a direction from the first face to the second face along the central portion. [0009] In one or more embodiments, the rib is adjacent a hinge axis.

[0010] In one or more embodiments, the rib has a length LR of the rib between rib ends (a width when viewed in the frame of reference of the closure) which is at least 50% of the local total hinge width WH.

[0011] In one or more embodiments, the rib has a width WR measured longitudinally in the frame of reference of the hinge which is at least 50% of a separation S between the first portion and second portion at a center of the hinge.

[0012] In one or more embodiments, the rib has a height of at least 0.005 inch.

[0013] In one or more embodiments, the first portion is a mounting base having an aperture, the second portion is a cap, the first condition is a closed condition, and the second condition is an open condition.

[0014] In one or more embodiments, spring bias of the living hinge will maintain the hinge in the open condition.

[0015] In one or more embodiments, the base is internally threaded and the cap, in the closed condition, surrounds and covers an upper rim portion of the base and has a detented engagement therewith.

[0016] In one or more embodiments, the second condition is a relaxed condition and the combination is molded of polypropylene.

[0017] In one or more embodiments, in the as-molded condition, a proximal-to-distal median of the hinge is generally upwardly concave and downwardly convex along the lateral portions.

[0018] The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG. 1 is a view of a prior art closure in an as-molded open condition/orientation.

[0020] FIG. 1A is an enlarged view of a hinge region of the closure of FIG. 1.

[0021] FIG. 2 is a top view of the hinge of the closure of FIG. 1.

[0022] FIG. 3 is a central transverse vertical sectional view of the hinge taken along line 3-3 of FIG. 2.

[0023] FIG. 4 is an end view of the hinge.

[0024] FIG. 5 is a medial sectional view of the hinge taken along line 5-5 of FIG. 2. [0025] FIG. 6 is an off-center transverse sectional view of the hinge taken along line 6-6 of FIG. 2.

[0026] FIG. 7 is a cutaway top view of a second closure in an open as-molded condition.

[0027] FIG. 8 is cutaway view of the second closure.

[0028] FIG. 9 is a bottom cutaway view of the second closure.

[0029] FIG. 10 is a side cutaway view of the second closure.

[0030] FIG. 11 is a medial sectional cutaway view of the second closure taken along line 11-11 of FIG. 7.

[0031] FIG. 12 is a sagittal cutaway sectional view of the second closure taken along line 12-12 of FIG. 7.

[0032] FIG. 13 is a central vertical transverse sectional cutaway view of the second closure taken along line 13-13 of FIG. 7.

[0033] FIG. 14 is a cutaway view of the second closure in a closed condition.

[0034] FIG. 15 is a rear cutaway view of the closed second closure.

[0035] FIG. 16 is a side cutaway view of the closed second closure.

[0036] FIG. 17 is a top cutaway view of the closed second closure.

[0037] FIG. 18 is a cutaway view of a third closure in an open as-molded condition.

[0038] FIG. 19 is a second cutaway view of the third closure.

[0039] FIG. 20 is a cutaway top view of the third closure.

[0040] FIG. 21 is a medial sectional cutaway view of the third closure taken along line

21- 21 of FIG. 20.

[0041] FIG. 22 is a sagittal cutaway sectional view of the third closure taken along line

22- 22 of FIG. 20.

[0042] FIG. 23 is a central vertical transverse sectional cutaway view of the third closure taken along line 23-23 of FIG. 22.

[0043] Like reference numbers and designations in the various drawings indicate like elements. DETAILED DESCRIPTION

[0044] FIG. 1 shows a prior art closure system 20 in an open condition. The illustrated exemplary system 20 comprises a unitarily molded combination comprising a living hinge 22 coupling a first portion 24 to a second portion 26. The exemplary first portion is a fixed portion such as a mounting base or "frame". The exemplary mounting base 24 is formed as an essentially fully open ring or frame structure. The exemplary base 24 comprises a sidewall extending from a lower end formed by a lower rim 28 to an upper end formed by an upper rim 30 and has an inner/inboard/interior surface 32 and an outer/outboard/exterior surface 34. The inner surface 32 may bear a feature 36 such as a thread or an annular bead for respectively screwing onto or snapping onto a neck of a mating container body (not shown) and securing to a complementary feature thereon. Although the exemplary rim 30 defines a mouth that is essentially fully open, alternative implementations may have a smaller opening such as defined along a web extending radially inward from the upper end of the sidewall. The exemplary frame has a central vertical axis 1000 (vertical and longitudinal from the point of the container mouth).

[0045] Other possible mounting include adhesive mounting, solvent bond mounting, thermal weld mounting and like.

[0046] The exemplary second portion 26 is a closure member or element. The closure member 26 is articulatable by flexing of the hinge 22 relative to the base 24 when in a closed condition and one or more open conditions.

[0047] The exemplary closure member 26 is formed as a cover, more particularly, a combination of cap and plug. The closure member has a sidewall 40 having an upper (when closed on an upright package) portion 42 and an inwardly rebated lower portion 44. The lower portion extends upward from a lower rim 46. The sidewall has an inner surface 48 and an outer surface 50. Along the lower portion 44 the outer surface 50 is dimensioned to be received within an upper portion of the base 24. The upper portion 42 forms a shoulder 52 at junction with the lower portion 44 along the outer surface 50. In the exemplary

implementation, the shoulder 52 is positioned to closely face or contact the upper rim 30 in the closed condition.

[0048] The exemplary closure element 26 further includes a transverse web 54 forming a top of the closure member. The surface 50 along the lower portion 44 and mating surface 32 may bear cooperating detent moieties (e.g., rib and channel or rib pairs) for detenting the closure element in the closed condition. Yet other locking features may include latches or the like. [0049] FIG. 1 A shows further details of the hinge 22.

[0050] The exemplary living hinge 22 is un-slitted and extends continuously from a first (proximal) end 80 at the base to a second (distal) end 82 at the cap. The exemplary hinge has a left edge 84 and a right edge 86. For convenient reference in not limiting any use, left and right are viewed from the perspective of a viewer looking across the base 24 toward the hinge 22 from slightly above. The exemplary hinge has a first (inboard) face 88 and a second (outboard) face 90 (FIG. 3). The exemplary hinge has three portions or sections distributed laterally: a central portion 92; a left portion 94; and a right portion 96. In the as-molded condition (which corresponds to one open condition but not necessarily a relaxed open condition) transverse cross-sections of the hinge and its portions 92, 94, and 96 are essentially straight. The portions 94 and 96 have proximal ends at junctions with adjacent ends of the central portion 92 and extend downward to the distal ends or edges 84 and 86 mentioned above. The exemplary downward angle is shown as θι (FIG. 3) along a transverse central vertical plane 1006 (FIG. 2). Due to the curvature of the exemplary base 24 and closure member 26, the angle increases away from the plane 1006. Exemplary θι is approximately 9° along the plane 1006 increasing to approximately 15° at the edges 80 and 82. Along the portions 94 and 96, the underside 90 is downwardly concave in longitudinal vertical section (FIGS. 4-6). The central portion 92 is of none or lesser curvature. The exemplary central portion comprises a transverse channel 120 to provide flexibility about a hinge axis 1010 (shown schematically and potentially shifting slightly during flexing).

[0051] FIG. 7 shows a closure 200 comprising a hinge 202 between a base 204 and a closure member 206. Except for a modification to the hinge, these and their associated features may be similar to the closure 20 of FIG. 1. For ease of illustration, however, the closure member 206 is shown as a mere cover with rim-to-rim mating (e.g., the shoulder 52 of FIG. 1 is now the rim mating with the rim 30).

[0052] A difference between the hinge 202 and the hinge 22 is the presence of a reinforcement 220 (FIG. 8). The exemplary reinforcement 220 is formed as a transversely elongate rib along the outboard face or underside 90 extending from a first end 230 to a second end 232 and between a proximal edge 234 and a distal edge 236. FIG. 9 shows a length LR of the rib between the ends (a width when viewed in the frame of reference of the closure). LR is a substantial fraction of the total hinge width WH at the rib or at the transverse centerplane of the hinge if slightly different). The exemplary rib thus spans portions of all three sections 92, 94, and 96 of the hinge. An exemplary LR is at least 50% of WH, more narrowly, at least 75% of WH or at least 80% of WH or at least 90% of WH. An exemplary rib width WR measured longitudinally in the frame of reference of the hinge may be a substantial fraction of a separation S between the sidewalls of the frame and cover. Again this may be at least 50% or at least 60%. The exemplary rib has thickness that tapers both transversely and longitudinally. FIGS. 11 and 12 show tapering longitudinally from a point of view of the closure or transversely from the point of view of the rib. In this direction, in the as-molded condition, the rib has a convex profile tapering to no essential thickness at its edges. FIG. 13 (particularly when contrasted with FIG. 3) shows the rib as having essentially constant thickness along the central portion 92 but then tapering generally constantly along the lateral portions of the hinge 94 and 96. Exemplary WR is at least 0.05 inch or about 0.07 inch.

Exemplary rib height or protrusion HR is at least 0.005 inch or at least 0.007 inch or about 0.01 inch

[0053] In terms of hinge action, the rib may have several effects. The rib added alone may increase restorative force to aid springback to the open condition. As is discussed further below, the combination of the rib and the channel 120 may create a convoluted profile that limits peak strain and associated set. In this embodiment, the tapering of the rib toward the edges helps limit the increase in restorative force caused by the rib when in the closed condition (so as to avoid overcoming the detenting force of any latch feature). The edges may experience a difference in deformation (relative to the center) that makes the rib addition particularly significant.

[0054] FIGS. 18-23 show a third closure system 300 otherwise similar to the closure system 200 except for features of the hinge 302 discussed below. In this example, a rib 320 is associated with a channel 322 in the inboard face. The channel 322 is deeper, broader, and more laterally extensive than the corresponding channel of the second closure 200. In this example, the channel and rib extend essentially the entire width of the hinge without the vanishing taper along the lateral portions of the second hinge 202. This makes more extensive use of the strain/set reduction noted above. Without the channel structure providing a convoluted longitudinal section, there would be a relatively higher strain in the closed condition. This results in the hinge taking a set that reduces the amount of springback (i.e., how far toward the as-molded condition the closure springs back to in a relevant time period such as a second or two after release from the closed condition). The convoluted

cross-section provided by the channel structure distributes the closed condition deformation resulting in lower peak strains and thus less of a plastic or short term set. By extending the channel and convolution to the edges, the adverse effect of adding only a rib extending to the edges is overcome in that the channel structure deforms and accommodates a partial flattening in the closed condition. Similar or greater rib dimensions WR and HR may exist as in the FIG. 7 embodiment.

[0055] Exemplary closure material is a molded plastic such as a conventional polypropylene or copolymerpolypropylene (CoPP).

[0056] The use of "first", "second", and the like in the description and following claims is for differentiation within the claim only and does not necessarily indicate relative or absolute importance or temporal order. Similarly, the identification in a claim of one element as "first" (or the like) does not preclude such "first" element from identifying an element that is referred to as "second" (or the like) in another claim or in the description.

[0057] Where a measure is given in English units followed by a parenthetical containing SI or other units, the parenthetical 's units are a conversion and should not imply a degree of precision not found in the English units.

[0058] One or more embodiments have been described. Nevertheless, it will be understood that various modifications may be made. For example, when applied to an existing basic system, details of such configuration or its associated use may influence details of particular implementations. Accordingly, other embodiments are within the scope of the following claims.