Child-resistant screw closure

Abstract: A squeeze and turn child resistant package including a container having a finish (46) and a closure having a base wall (26) and an outer peripheral flexible wall (28) depending from the base wall. The wall has an internal thread on the inner surface thereof, the finish has an external thread thereon. The closure has an internal surface with spaced flexible chordal lugs (70) extending circumferentially in the direction of removal of the closure. The container finish has opposed radially extending abutments (52). Each abutment includes a radial abutting surface (54). The finish of the container includes an integral radial projection (56) adjacent the radial abutting surface of the abutment which has a lesser radial extent than the abutment. The radial projection has a chordal surface extending to the intersection of the radial abutting surface on he finish such that the chordal lug (70) on the closure is forced toward the intersection when a closure is rotated in a retrograde direction to remove the closure without flexing the peripheral wall. The finish has stops (50) below the threads engaging a blunt end leading end (51) of the thread on the closure to limit the movement of the closure and orient the closure.

Description: This invention relates to child resistant packages and particularly to such packages which are of the squeeze and turn type. Background and Summary of the Invention In typical squeeze and turn child resistant packages, it is common to provide a container having opposed stop lugs and a closure which has lugs on the periphery thereof which engage the stop lugs on the container. To remove the closure, it must be squeezed to permit the lugs on the closure to be moved out of the path of the lugs on the container and the closure can then be unthreaded from the container. Typical patents showing such a construction are United States patents 3,949,893; 3,984,021; 4,116,351 as well as EPO WO 9/01924. Such child resistant packages have been produced and have been successful in the marketplace. However, they sometimes are difficult to use. When efforts are made to make such packages easier to use and more user friendly, the closure may be defeated if the lugs on the closure are bent backward and the closure is rotated in an unthreading direction (counter clockwise), even though the closure has not been squeezed. Further child resistant packages are disclosed in GB-A-2105693, GB-A-2011869, GB-A-1535051 and US-A-4117945. GB-A-2105693 makes known a child resistant closure arrangement in which abutting elements on a circular closure are disposed on a ring that is attached by legs to the lower end of a closure skirt. Such an arrangement is not satisfactory since the child resistant feature can be viewed through the gap between the ring and the skirt. GB-A-2011869 makes known a single-wall circular closure with a child resistant feature. GB-A-1535051 makes known a circular closure and an abutment stop arrangement on an associated container. US-A-4117945 makes known a standard circular squeeze-and-turn child resistant package that includes radial elements on a container shoulder and a closure skirt. Accordingly, among the objectives of the present invention are to provide a child resistant package which is readily usable by an adult; more user friendly; and which can not be readily defeated. In accordance with the invention, there is provided a squeeze and turn child resistant package as set forth in appended claim 1. Description of the Drawings FIG. 1 is an elevational view of a child resistant package embodying the invention. FIG. 2 is a sectional view taken along the line 2-2 in FIG. 1. FIG. 3 is a view similar to FIG. 2 showing the relative positions of the closure and the container when the closure is being removed. FIG. 3A is a view similar to FIG. 2 showing the relative positions of the closure and container when an attempt is made to remove the closure in without squeezing FIG. 4 is a fragmentary part sectional elevational view of a portion of the package. FIG. 5 is an elevational view of the container. FIG. 6 is a side elevational view of a container taken from the right in FIG. 5. FIG. 6A is a fragmentary enlarged sectional view taken along the line 6A-6A in FIG. 6. FIG. 7 is a plan view of the container shown in FIG. 5. FIG. 8 is a fragmentary enlarged plan view of a portion of the container. FIG. 9 is a perspective view of the closure. FIG. 10 is a sectional view taken along the line 10-10 in FIG. 9. FIG. 11 is a sectional view taken along the line 11-11 in FIG. 9. FIG. 12 is a bottom plan view of the closure. Description of the Preferred Embodiments Referring to FIGS. 1-12, the squeeze and turn child resistant package 20 embodying the invention comprises a container 22 and a closure 24. The container 22 is made of plastic such as polypropylene or polyethylene terpthalate and the closure is made of plastic, preferably polypropylene. The closure 24 includes a base wall 26 and a peripheral wall or skirt 28 which is generally oval in cross section having a long axis and a short axis. Opposed flat finger engaging portions 30 are provided at the long axis (FIGS. 2, 9) and have vertical ribs 32 to facilitate grasping between the thumb and the finger. The closure further includes an inner annular wall skirt 34 having dual threads 36 (FIG. 4, 11). The leading end of each of the threads 36 on the closure is a blunt end, 38 for purposes presently described. Referring to FIGS. 7 and 9, the container 22 is generally oval in horizontal cross section corresponding to the horizontal cross section of the closure 24 so when the closure is fully applied, the profiles of the closure 24 and container 22 conform. Thus, the container 22 has arcuate sides 40 and flat oppose sides 42 (FIG. 7). The container 22 further includes a shoulder 44 with a cylindrical finish 46 extending upwardly therefrom. The finish 46 has threads 48 complementary to the threads 36 on the closure 24. In addition an axial stop 50 is provided on each of the threads 48 and extends downwardly therefrom as shown in FIG. 6, for purposes presently described. Referring to FIGS. 7 and 8, the finish 46 is formed with radially opposed abutments 52, each of which has a radially extending and axially extending surface 54. An upwardly and circumferentially extending radial projection 56 having a lesser radial extent than abutment 52 is provided adjacent the abutting surface 54 and includes a chordal surface 58 intersecting the abutting surface 54. Abutment 52 includes a flat upper radial surface 60 intersecting the axial surface 54. Abutment 52 further includes a circumferentially extending projection 62 which extends circumferentially from the axial surface 54 in a direction opposite to projection 56. Projection 62 has an upper inclined surface 64 extending in the direction of rotation of the closure 24 which the closure 24 is applied to the container 22. The closure 24 includes opposed flexible chordal lugs 70 on arcuate walls 28. Each chordal lug 70 extends circumferentially in the direction of the removal of the closure and is hinged to the skirt along a vertical hinge area 72 and at its upper end on a horizontal hinge area 74 (FIGS. 2, 4, 11, 12). When the closure 24 is rotated to apply the closure to the container 22 the chordal lugs 70 engage the ramp surface 64 and flex past the abutments 52 to assume the position such as shown in FIG. 2 preventing the closure 24 from being unscrewed. When the closure is to be removed the wall 28 is squeezed at portions 30, as shown in FIG. 3, causing the chordal lugs 70 to be moved outwardly beyond the abutment surfaces 54 so that the closure 24 can be unthreaded. If an attempt is made to remove the closure without flexing the wall 28, the chordal lugs 70 will engage the intersection of the axial abutting surface 54 on the finish 46 and the radial projection 56 on the finish 4 causing the wall 28 to flex outwardly as shown in FIG. 3A and causing the chordal lugs 70 to change there angular relationship further forcing the ends of the chordal lugs 70 into the intersection. When the closure 24 is applied to the container 22 the blunt ends 38 on the threads of the closure 24 engage the stops 50 on the finish 46 (FIG. 6A). Each stop 50 includes a complementary axial surface 51 and thickened at its free end to strengthen the stop 50. This limits the rotation of the closure 24 and align the oval closure 24 with the oval container 22. At the same time the stops 50 prevent over tightening and facilitates the removal of the closure by an adult. It can thus be seen that there has been provided a child resistant package which is readily usable by an adult; more user friendly; and which can not be readily defeated.

Claims: A squeeze and turn child resistant package comprising a plastic container (22) having a cylindrical finish (46) with an external thread (48), a generally oval shoulder (44) spaced beneath said thread (48), opposed radially extending abutments (52) on said shoulder, each said abutment (52) having a radially and axially extending abutment surface (54), and integral radial projections (56) adjacent to said radial abutment surfaces (54) of said abutments (52), each said radial projection (56) having a lesser radial extent than the associated abutment (52) and including an outwardly arcuate surface (58) intersecting the associated radial abutment surface (54) at a right angle, and a plastic closure (24) having a base wall (26), an inner annular skirt (34) extending from said base wall (26) with an internal thread (36) for receipt over said external thread on said container finish (46), and a generally oval outer flexible peripheral wall (28) concentric with said inner skirt and adapted to extend to said shoulder (44) of said container (22) so as to enclose said abutments (52) and said radial projections (56), said generally oval outer flexible peripheral wall (28) having opposed external finger engaging portions (30) at the ends thereof and opposed internal flexible chordal lugs (70) hinged from an internal surface of said wall (28) at portions of said wall (28) between said finger portions (30), the flexible chordal lugs (70) extending circumferentially in the direction of removal of the closure (24) and being disposed so as to be forced toward the intersection between said arcuate surfaces (58) of said radial projections (56) and said abutment surfaces (54) of said abutments on rotation of the closure (24) in the direction of removal in the absence of distortion of said wall caused by squeezing together said finger portions (30) and outward flexing of the portions of said wall (28). The squeeze and turn child resistant package set forth in claim 1 wherein said finish of the container has downwardly extending axial stops (50) extending downwardly from the threads thereof, and said closure has a blunt leading end (38) on the threads thereof engaging said downwardly extending stops on the finish to orient the closure (24) with respect to the container (22) such that the generally oval shape of the outer flexible peripheral wall (28) of the closure (24) is aligned with the generally oval shape of the shoulder (44) of the container (22). The squeeze and turn child resistant package set forth in claim 2 wherein said shoulder (44) of said container (22) and said outer flexible peripheral wall (28) of said closure (24) have a long axis and a short axis, wherein the opposed external finger engaging portions (30) of the closure (24) are formed by opposed vertical flat surfaces on the long axis of the closure (24) and wherein opposed vertical flat surfaces are formed on the long axis of the container (22) to form gripping surfaces for holding the container (22). The squeeze and turn child resistant package set forth in claim 1 wherein said chordal lugs (70) are hinged to the inner surface of the wall (28) along a vertical axis and a horizontal axis. A container for a squeeze and turn package comprising a plastic container (22) having a cylindrical finish (46) with an external thread (48), a generally oval shoulder (44) spaced beneath said thread, opposed radially extending abutments (52) on said shoulder, each abutment (52) including a radially and axially extending abutment surface (54), and integral radial projections (56) adjacent said radial abutment surfaces (54) of said abutments (52), each said radial projection (54) having a lesser radial extent than said associated abutment (52) and having an outwardly arcuate surface (58) intersecting said associated radial abutment surface at a right angle. The container set forth in claim 5 wherein said container has one or more axial stops (50) extending downwardly from said thread (48) of said finish (46). The container set forth in claim 5 wherein the generally oval shoulder (44) has a long axis and a short axis and has opposed vertical flat surfaces at the long axis. A plastic closure (24) for a squeeze and turn child resistant package which includes a container (22) having a cylindrical finish (46) with external threads (48), a generally oval shoulder (44) spaced beneath said threads, opposed radially extending abutments (52) on said shoulder and integral radial projections (56) adjacent said abutments said plastic closure having a base wall (26), a generally oval outer peripheral flexible wall (28) depending from said base wall which is adapted to extend to said shoulder (44) of said container (22) so as to enclose said abutments (52) and said radial projections (56), and an inner annular skirt (34) concentric with said outer wall (28) depending from said base wall and having internal thread means (36) thereon adapted to engage said external threads (48) on said container (22), said peripheral (48) flexible wall (28) of said closure (24) having opposed finger engaging portions (30) at the ends thereof and an internal surface to which opposed flexible chordal lugs (70) are hinged at portions of the internal surface between said finger portions (30) so as to extend circumferentially in the direction of removal of the closure. The plastic closure set forth in claim 8 wherein said closure (24) has a blunt leading end (38) on the threads (36) thereof adapted to engage downwardly extending stops (50) on the finish to orient the generally oval outer peripheral flexible wall of the closure (24) with the generally oval shoulder (44) of the container (22). The plastic closure set forth in claim 9 wherein the generally oval outer peripheral flexible wall has a long axis and a short axis and the opposed finger portions are opposed vertical flat surfaces on the long axis. The plastic closure set forth in claim 8 wherein said chordal lugs (70) are hinged to the inner surface of the outer wall (28) along a vertical axis and a horizontal axis.

Inventors: KUSZ MAXIMILLIAN, KUSZ, MAXIMILLIAN
Applicants: OWENS ILLINOIS CLOSURE INC, OWENS-ILLINOIS CLOSURE INC.
Application year: 1997
Main classification: B65D50
IPC codes: B65D50, B65D41