Torque-resistant closure for a hermetically sealed container

Abstract: An improved closure insert (20) is provided for throat region (14) of a blow-moulded container (10). This closure insert (20) is provided with a scabrous perimeter (28) and is permanently molded into the container throat region (14) during container formation from a parison. The resulting seal resists loosening or disturbance when off-axis force or torque force is applied to the closure insert (20) during container opening. The closure insert (20) can be a subassembly constituted by removable parts that provide a variety of access options to the container contents.

Description: This invention relates to improved closures for the throat region of hermetically sealed, blow-moulded containers and in particular to blow moulded, filled and sealed container structures that incorporate such closures. Hermetically-sealed containers can be readily produced by the so-called blow/fill/seal techniques. Utilising such techniques, a container body is first blow moulded from an extruded parison segment, then charged (or filled) with a desired liquid or solid contents, and thereafter immediately sealed by a preformed insert while additionally moulding the parison segment at the container neck and throat region about the inserted, preformed closure subassembly. See, for example, the container structure disclosed in US Patent No 4, 596, 110 to Weiler. US A 4,539,172 illustrates a method of blow moulding a container having an integral inner dispensing outlet formed by a tubular member, with a sterile pouring lip and sterile threads below the pouring lip. The present invention contemplates a preformed closure insert permanently received in the neck portion of a container formed from a thermoplastic material wherein the insert is provided about the perimeter thereof with a scabrous surface that provides increased contact area between the insert and the inner surface of the container neck or throat portion contiguous therewith. The aforementioned scabrous surface is in the form of a band of substantially axially extending and circumferentially spaced ribs, can be knurled, serrated, undulating, or otherwise roughened. The closure insert can be a single piece moulded item such as a nozzle with or without a pierceable membrane, or a subassembly constituted by two or more parts. One aspect of the invention provides a hermetically sealed container of a thermoplastic material and comprising a body portion having an upper end terminating in a neck portion unitary therewith; a throat portion unitary with the neck portion; a preformed closure insert immobilised within the throat portion, the closure insert having a scabrous surface defined by axially aligned ribs uniformly spaced from one another and an axially extending passageway defined therethrough and a removable overcap unitary with the throat portion and delineated by a peripheral frangible web circumscribing the closure insert above the scabrous perimeter surface wherein the thermoplastic material in the throat portion of the container is in intimate contact with the scabrous perimeter surface and wherein spaces between the ribs are filled by the thermoplastic material. Preferably, the scabrous perimeter surface may have an actual-to-apparent contact surface ratio of at least about 3. According to an optional feature of this aspect of the invention, the removable overcap may be hollow and spaced from the closure insert. According to another optional feature of this aspect of the invention, the removable overcap may be in intimate contact with a removable portion of a closure insert subassembly whereby the removable portion of the closure insert subassembly can be removed together with the overcap. Preferably, the closure insert may be a subassembly; a luer connector; a multiple entry closure; a nozzle provided with a threaded protective cap; or a transfer spike surrounded by a guide skirt. According to yet another optional feature of this aspect of the invention, the closure insert is a subassembly that includes a base member immobilised within the throat portion and a multiple entry closure member removably secured to the base member. Preferably, the base member may include a base immobilised within the throat portion and a stem extending unitarily from the base and defining an access aperture, the multiple entry closure member including a gripping portion and a stem extending unitarily from the gripping portion and defining an access passageway, the stem of the closure member being removably secured within the stem of the base member. According to another optional feature of this aspect of the invention, the stem of the base member may include an inner surface having a pair of spaced apart threads extending circumferentially and spirally around a portion thereof, the stem of the closure member including an outer surface having a pair of lips projecting outwardly therefrom and extending partially circumferentially around a portion thereof, the lips being engaged between the pair of threads when the base member and the closure member are removably secured to each other. Alternatively, the stem of the base member and the stem of the closure member may have luer tapered portions in contact with one another. Preferably, the container may further comprise a removable overcap unitary with the throat portion and covering the multiple entry closure member, the overcap being delineated by a peripheral frangible web circumscribing the multiple entry closure member. A further aspect of the invention provides a method of forming a thermoplastics container, comprising providing an extruded parison, inserting into the parison a closure insert as defined having a scabrous perimeter surface defined by axially aligned ribs spaced from one another, the insert being placed in a region of the parison to be formed into a throat of the container, and compressing said parison region about the scabrous perimeter surface to form a container throat having the insert immobilised therein, the method optionally including one or more further steps to form a final product. Preferably, the parison is may be moulded to form an overcap closing the container. Brief Description of the Drawings In the drawings, FIGURE 1 is a perspective view of one embodiment of a container structure of the invention in its blow moulded, filled and sealed configuration; FIGURE 2 is an enlarged fragmentary sectional view of the container structure of Figure 1 in elevation; FIGURE 3 is a sectional view taken along the plane of 3-3 of Figure 2; FIGURE 4 is a view similar to Figure 2, but with all portions in section, the overcap broken away and removed, and the closure subassembly exploded; FIGURE 5 is an enlarged perspective view of a cap provided with a pierceable multiple entry membrane; FIGURE 6 is an elevational view showing a parison section partly moulded and with a closure insert; FIGURE 7 is an elevational view similar to that of Figure 6 but showing the parison section fully moulded about the closure insert subassembly; FIGURE 8 is a fragmentary elevational view, partly in section, showing an alternative embodiment of a container structure of this invention; FIGURE 9 is a fragmentary elevational view, partly in section, showing yet another embodiment of a container structure of this invention; FIGURE 10 is a perspective view of an insert suitable for practicing the present invention and showing a male luer lock connector provided with external lugs; FIGURE 11 is a side elevational view, partly in section, and showing a male luer lock connector or the like provided with internal threads for engaging a hypodermic needle; FIGURE 12 is a side elevational view, partly in section and showing a spike surrounded by a skirt for guidance and equipped with a scabrous perimeter surface in accordance with the present invention; FIGURE 13 is a fragmentary elevational view, partly in section, showing yet a further alternative embodiment of a container structure of this invention; FIGURE 14 is a perspective view of the closure insert shown in FIGURE 13; FIGURE 15 is a perspective, exploded view of the base member and multiple entry closure member of the closure insert shown in FIGURES 13 and 15; and FIGURE 16 is a sectional view taken along the plane 16-16 of FIGURE 13. Detailed Description of Preferred Embodiments Referring to FIGURES 1 and 2, a hermetically sealed, thermoplastic container 10 embodying the present invention includes a body portion 12, terminating in a neck portion that also defines a throat portion 14 unitary with the neck portion as well as with the body portion, and a removable overcap 16 unitary with throat portion 14 and delineated by frangible web 18. Received within throat portion 14 is closure insert 20 constituted by a cap 22 and hollow body 24 (FIGURES 2 and 4) that defines an open, axial access passageway 26 to container body portion 12. Hollow body 24 is provided with a band of scabrous perimeter surface 28 into which is molded the thermoplastic material from which container 10 is fabricated. The thermoplastic material can be a conventional molding material such as high density polyethylene, low density polyethylene, polypropylene, and the like, compatible with the contemplated container contents. Containers embodying the present invention can have a wide variety of shapes and capacities. The closure inserts contemplated by the present invention are preformed, for example by injection molding, and can have a wide variety of dispensing configurations depending upon contemplated end use. Single piece inserts as well as subassemblies are contemplated, as will be discussed and illustrated in greater detail hereinbelow. However, in all instances the closure insert is provided with a scabrous perimeter, e.g., ribbed, knurled, serrated, etc., that provides an increased surface area for intimate contact with the thermoplastic container material during molding. The scabrous surface is rough to the touch because of the bumps or projections that are present. The semisoft thermoplastic material of the container envelops these bumps or projections during molding and effectively immobilizes the insert within the throat or neck of the container. The scabrous outer perimeter surface 28 of closure insert 20, shown in FIGURES 2, 3 and 4, is in the form of substantially uniformly spaced ribs 30 generally parallel to the longitudinal axis of access passageway 26. FIGURE 3 shows a container in which thermoplastic material of container throat portion 14 fills completely the interstices or channels 29 between adjacent ribs 30 and immobilizes the insert by forming a permanent seal between the closure insert 20 and throat portion 14 during molding. Moreover, the scabrous perimeter surface of the closure insert permits more of the thermoplastic material to be retained in the container throat region as the material is compressed about the insert during molding. This, in turn, thickens the container wall about the insert and thereby rigidifies and strengthens the throat region against later dislodgement of the closure insert as the container is being opened in preparation for use. The scabrous perimeter surface of the closure insert provides an actual contact surface area that is considerably larger than the apparent contact surface area therebetween. Preferably, the actual-to-apparent contact surface area ratio is at least about 3. Closure insert 20 may be a subassembly that includes removable cap 22 for sealing access passageway 26. Cap 22 may also be provided with a scabrous (e.g ribbed) external surface into which a portion of overcap 16 is molded so that cap 22 is in intimate contact with and can be removed together with overcap 16 when frangible web 18 is severed. If, on the other hand, it is preferred for cap 22 to remain in place, maintaining access passageway 26 sealed while and after overcap 16 is removed, overcap 16 is molded in a known manner in a hollow configuration so as to remain spaced from cap 22 as the container is fabricated. In the latter case, access to container contents can be gained in several ways, to wit, by removing the cap 22 from stem 32, as illustrated in FIGURE 4, or by perforating a membrane or web 34 in cap recess 36 by means of a draining spike or a cannula. Stem 32 can have controlled or shaped inside and/or outside diameters, luer tapers, and the like features to facilitate interconnection with other receptacles or dispensing devices. For multiple entries into container contents without removal of cap 22 from stem 32, cap recess can be filled with an elastomeric material 38, e.g., rubber, as illustrated in FIGURE 5 for cap 42 which cap in all other respects is the same as cap 22 shown in FIGURES 2 and 4. The insertion of a preformed closure insert 20 into a thermoplastic container during container fabrication is illustrated in FIGURES 6 and 7. An extruded parison segment 45 is held by vacuum assisted holding jaws 47 and 49 in position between main mold halves 51 and 53 as container body portion 12 is formed in a known manner, for example, as described in U.S. Patent No. 4,901,873 to Weiler et al. Thereafter, preformed closure insert 20 is positioned as shown in FIGURE 6. Next, sealing mold halves 55 and 57 are moved inwardly toward one another (FIGURE 7) to compress the remaining, upper parison portion about closure insert 20 so as to form throat region 14 as well as overcap 16 while urging the thermoplastic material of the parison into the interstices between adjacent longitudinal ribs 30. In this manner a closure insert is effectively and expeditiously permanently secured within throat region 14. FIGURES 8 through 12 illustrate the diverse types of closure inserts that can be accommodated while utilizing the present invention. Referring to FIGURE 8, closure insert 60 is a hollow, substantially cylindrical member provided with spaced, longitudinally extending ribs 62 about its periphery. Pierceable, non-coring membrane 64 extends across insert 60 to seal access passageway 66. A rubber composition 70 fills outer recess 68 for multiple entry applications. Hollow overcap 72, unitary with the throat region, protects pierceable insert 60 against contamination. Overcap 72 can be removed by grasping wings 76 and 78 and twisting so as to break frangible web 80. FIGURE 9 shows closure insert subassembly 82 that comprises nozzle 84 equipped with a threaded protective cap 86. Base 88 of nozzle 84 is provided with peripheral, spaced ribs 85 in intimate contact with throat region 90. Hollow overcap 89 is unitary with container throat region 90 and is connected thereto by frangible web 92. Wings or tabs 91 and 93 on overcap 89 facilitate its manipulation, especially by senior citizens or those suffering from arthritis, when readying nozzle 84 for dispensing of container contents. FIGURE 10 illustrates a closure insert provided with several interconnecting means. In particular, closure insert 94 comprises hollow stem 96 that defines access aperture 98 having a controlled or shaped inside diameter, e.g., a luer taper for receiving a luer fitting. Stem 96 terminates in outwardly extending lugs 100 and 102 sized to engage luer lock threads, e.g., of the type shown in FIGURE 11. Base 99 of insert 94 is provided with peripheral, axially aligned and spaced ribs 101 for engaging the thermoplastic material of a container throat region and receiving some of the thermoplastic material therebetween. FIGURE 11 shows a male luer lock connector 105 having a ribbed base 107 and equipped with internal threads 109 for engaging lugs 111 and 113 on hub 115 on hypodermic needle 117. Ribbed base 107 is provided with a plurality of spaced, substantially parallel ribs 108 with channels or interstices 110 therebetween. Ribs 108 merge into a common solid peripheral band or ring 116 at the upper portion of base 107 and unitary therewith. Fitments other than a luer lock connector can be provided in a like manner, as desired, to facilitate the dispensing of the container contents. For example, the outer surface 106 of connector 105 can receive in a mating relationship one end of tubing. FIGURE 12 shows a spike connector 119 having a ribbed base 121 of similar configuration to that shown in FIGURE 11 and embedded in throat region 120 of thermoplastic container 122. Transfer spike 124 is surrounded by guide skirt 126 which facilitates the penetration of spike 124 into a stoppered container 130 so as to drain the contents thereof as container 130 is urged against spike 124. FIGURES 13-16 depict a closure insert 132 in the form of a subassembly including a base member 134 and a removable closure member such as multiple entry closure member 136. Referring to FIGURES 13 and 14, base member 134, which is substantially cylindrical, includes a cylindrical skirt portion 138 which is immobilized within the throat region 142 of the container and is provided with a scabrous perimeter surface such as that defined by peripheral, spaced longitudinally positioned ribs 140 in intimate contact with throat region 142 and extending circumferentially around the periphery of skirt portion 138. Ribs 140 merge into a common solid peripheral band or ring 144 at the upper portion of skirt portion 138 and are unitary therewith. Base member 134 is further provided with a hollow, cylindrical stem 146 which extends upwardly from the ring 144 and is unitary therewith. Cylindrical stem 146 defines an access aperture 148 (FIGURE 15). Stem 146 also includes an inner surface 150 (FIGURE 15) having two threads 151 and 152 formed therein which extend circumferentially and spirally around a portion of the inner surface 150. More particularly, and referring to FIGURES 13 and 16, threads 151 and 152 are spaced apart from each other, with thread 151 extending circumferentially and spirally around approximately one half of the inner surface 150 and thread 152 extending circumferentially and spirally around the opposed half of the inner surface 150. Internally threaded stem 146 also defines a luer lock adapted to receive a hypodermic needle in a manner similar to that shown in FIGURE 11. Inner surface 150 further includes a frustoconical tapered portion 156 (FIGURE 15), e.g., a luer tapered portion, adjacent to access aperture 148. Tapered portion 156 converges inwardly from access aperture 148 into the inner surface 150 of stem 146. The multiple entry closure member 136, which preferably is substantially cylindrical, is comprised of a hollow, substantially cylindrical gripping portion 153 provided with spaced, longitudinally positioned ribs 154 which extend circumferentially around the periphery thereof. Member 136 is further provided with a hollow, substantially cylindrical stem 158 (FIGURE 15) which extends downwardly from the end of gripping portion 153. As shown in FIGURES 13 and 16, the stem 158 has an inner cylindrical surface 160 defining an access passageway 162. Further, stem 158 has an outer surface with a frustoconical tapered stem portion 166 (FIGURE 15), which can be a luer tapered portion complementary to tapered portion 156, converging downwardly from the end of gripping portion 153, and a cylindrical stem portion 168 (FIGURE 15) extending downwardly from portion 166 and separated therefrom by a step 170 (FIGURE 15). A pair of diametrically opposed lips or ridges 172 and 174 project radially outwardly from the outer surface of cylindrical stem portion 168 and extend partially around the circumference thereof. More particularly, lip 172 extends circumferentially around a portion of one side of stem portion 168 while lip 174 extends circumferentially around the side of stem portion 168 diametrically opposed to the side with lip 172. A pierceable, non-coring membrane 176 is provided across gripping portion 153 to seal the access passageway 162. An elastomeric self-sealing composition 178 fills an outer recess 180 in gripping portion 153 for multiple entry applications. The hollow overcap 182, unitary with the throat region 142 of the container, protects the closure member 136 against contamination. The overcap 182 is connected to the throat region 142 by a frangible web 184 and is provided with wings or tabs 186 and 188 to facilitate removal thereof. As best seen in FIGURES 13 and 15, the closure member 136 is secured to the base member 134. More particularly, the stem 158 of closure member 136 is removably received and secured within the inner surface 150 of stem 146 of base member 134. Lips 172 and 174 on stem 158 coact with threads 151 and 152 of base member 134 to provide a bayonet lock between members 134 and 136. Moreover, tapered portion 166 on stem 158 frictionally engages tapered portion 156 on stem 146. It is understood, of course, that the bayonet and luer lock connecting means disclosed herein are but two of several known means for removably securing members such as members 134 and 136 together and that such other means are within the scope of this invention. According to this alternative embodiment of the present invention, and to allow dispensing of the container contents, overcap 182 is first removed from the container, i.e., by grasping wings 186 and 188 thereof and twisting off so as to break frangible web 184. The container contents can then be dispensed in several different ways. Initially, the contents can be removed with a syringe or a spike through the membrane 176 of multiple entry closure member 136. Alternatively, the contents can be poured out through base member 134 by unscrewing and removing multiple entry closure member 136 from base member 134. Moreover, if only a portion of the contents have been removed or poured out, overcap 182 can be replaced on the top of closure member 136 or base member 134, respectively to protect the contents from contamination. Additionally, a hypodermic needle can be fitted to base member 134 and the contents dispensed through the needle. The foregoing specification and the drawings are to be taken as illustrative but not limiting of the present invention. Still other closure insert configurations utilizing the scope of the present invention as defined in the claims are possible, and will readily present themselves to those skilled in the art.

Claims: A hermetically sealed container (10) of a thermoplastic material and comprising: (a) a body portion (12) having an upper end terminating in a neck portion unitary therewith; (b) a throat portion (14) unitary with the neck portion: (c) a preformed closure insert (20) immobilised within the throat portion, the closure insert (20) having a scabrous surface (28) and an axially extending passageway defined therethrough; and (d) a removable overcap (16) unitary with the throat portion and delineated by a peripheral frangible web (18) circumscribing the closure insert above the scabrous perimeter surface wherein the thermoplastic material in the throat portion (14) of the container is in intimate contact with the scarbrous perimeter surface and wherein spaces between the ribs are filled by the thermoplastic material characterised in that said scabrous surface is defined by axially aligned ribs spaced from one another. The container of claim 1 wherein the scabrous perimeter surface (28) has an actual-to-apparent contact surface ratio of at least about 3. The container of claim 1 or claim 2 wherein the removable overcap (16) is hollow and is spaced from the closure insert (20). The container of any of claims 1 to 3 wherein the removable overcap (16) is in intimate contact with a removable portion of a closure insert subassembly (22) whereby the removable portion of the closure insert subassembly can be removed together with the overcap (16). The container of any of claims 1 to 4, wherein the closure insert is: (i) a subassembly (132); (ii) a luer connector (105); (iii) a multiple entry closure (136); (iv) a nozzle (84) provided with a threaded protective cap (86); or (v) a transfer spike (124) surrounded by a guide skirt (126). The container of any claim 1 to 4 wherein the closure insert (20) is a subassembly (132) that includes a base member (134) immobilised within the throat portion (14) and a multiple entry closure member (136) removably secured to the base member (134). The container of claim 6 wherein the base member (134) includes a base immobilised within the throat portion and a stem (146) extending unitarily from the base and defining an access aperture (148), the multiple entry closure member (136) including a gripping portion (153) and a stem (158) extending unitarily from the gripping portion (153) and defining an access passageway (162), the stem of the closure member being removably secured within the stem of the base member. The container of claim 7 wherein the stem (146) of the base member includes an inner surface (150) having a pair of spaced apart threads (151, 152) extending circumferentially and spirally around a portion thereof, the stem (158) of the closure member including an outer surface having a pair of lips (172, 174) projecting outwardly therefrom and extending partially circumferentially around a portion thereof, the lips being engaged between the pair of threads (151, 152) when the base member (134) and the closure member (136) are removably secured to each other. The container of claim 8 wherein the stem (146) of the base member and the stem (158) of the closure member have luer tapered portions (156, 166) in contact with one another. The container of any claims 6 to 9 further comprising a removable overcap (16) unitary with the throat portion (14) and covering the multiple entry closure member (130), the overcap being delineated by a peripheral frangible web (184) circumscribing the multiple entry closure member (136). A method of forming a thermoplastics container, comprising: providing an extruded parison inserting into the parison a closure insert (20, 132) as defined in any of claims 1 to 10, having a scabrous perimeter surface defined by axially aligned ribs (30, 140) spaced from one another, the insert being placed in a region of the parison to be formed into a throat of the container, and compressing said parison region about the scabrous perimeter surface to form a container throat having the insert immobilised therein, the method optionally including one or more further steps to form a final product. A method of claim 12, wherein the parison is moulded to form an overcap closing the container. The use of moulding apparatus to form a container of any of claims 1 to 10 or in performing a method of claim 11 or claim 12.

Inventors: WEILER GERHARD H, WEILER, GERHARD H.
Applicants: AUTOMATIC LIQUID PACKAGING, AUTOMATIC LIQUID PACKAGING, INC.
Application year: 1995
Main classification: B65D1
IPC codes: B65D1, B65D41, B29C70, B29C49