Lightweight child-resistant closure
View Patent ↗A child-resistant container closure includes a base cap having a top, a skirt, and a plurality of asymmetric teeth recessed in the skirt below the top, and a cover cap having a top, a skirt, and a plurality of asymmetric downwardly extending teeth adjacent to the skirt, the teeth being adapted for asymmetric engagement with the base cap teeth, the skirt having a plurality of interspersed vertical legs each spaced apart from adjacent legs by vertical openings, the legs being joined at a bottom end of the skirt by a support ring, the base cap teeth each having a sloped sliding face to ensure that one of the cover cap teeth will drop into a notch between adjacent base cap teeth when the cover cap is rotated in one direction.
1. A child-resistant container closure comprising:
a base cap having a top and a skirt depending downwardly from the top, the skirt including a plurality of asymmetric teeth recessed below the top, internal threads for engaging a neck of the container, and a bottom end; and
a cover cap having a top and a skirt depending downwardly from the top, the top including a plurality of asymmetric downwardly extending teeth adjacent to the skirt, the teeth being adapted for asymmetric engagement with the base cap teeth, the skirt having a plurality of interspersed vertical legs each spaced apart from adjacent legs by vertical openings, the legs being joined by a support ring, the cover cap teeth being formed on an inner surface of the legs;
wherein when the cover cap is rotated in a first direction, the cover cap teeth positively engage the base cap teeth to cause the base cap to rotate along with the cover cap in the first direction;
wherein when the cover cap is rotated in a second direction in combination with a predetermined downward force urging the cover cap top toward the base cap top, the cover cap teeth positively engage the base cap teeth to cause the base cap to rotate along with the cover cap in the second direction, the base cap teeth each having a sloped sliding face to ensure that one of the cover cap teeth will drop into a notch between adjacent base cap teeth when the cover cap is rotated in the second direction;
wherein when the cover cap is rotated in the second direction in the absence of the predetermined downward force, the base cap remains nonrotating and the cover cap teeth slidably engage with the base cap teeth causing an audible clicking sound as pairs of teeth jump from one sliding engagement to another;
wherein each of the base cap teeth has an opening face on one side of the sliding face and each of the cover cap teeth has an opening face on one side of the sliding face; and
wherein at least one of the base cap teeth opening faces and the cover cap teeth opening faces are sloped from vertical to enable the opening faces of the base cap teeth and cover cap teeth to slide over one another in the absence of the predetermined downward force.
2. The closure of claim 1 , the base cap teeth being formed in an outer wall of the base cap skirt.
3. The closure of claim 1 , the legs each further comprising an inwardly protruding raised ridge for centering the cover cap on the base cap.
4. The closure of claim 1 , each of the base cap teeth further having a closing face on an opposite side of the sliding face from the opening face;
wherein the closing face has a slope in the range of vertical to about 20 degrees from vertical;
wherein the opening face has a slope in the range of about 20 degrees to about 45 degrees from vertical; and
wherein the sliding face has a slope in the range of about 2 degrees to about 10 degrees from horizontal;
such that a junction between the closing face and the sliding face is disposed above a junction between the opening face and the sliding face.
5. The closure of claim 4 ,
wherein the closing face has a slope of about 20 degrees from vertical;
wherein the opening face has a slope of about 30 degrees from vertical; and
wherein the sliding face has a slope of about 6 degrees from vertical.
6. The closure of claim 4 , wherein each of the closing face and the opening face is undercut with respect to the base cap skirt to enhance the engagement between the base cap teeth and the cover cap teeth.
7. The closure of claim 1 , each of the cover cap teeth further having a closing face on an opposite side of the sliding face from the opening face;
wherein the closing face has a slope in the range of about vertical to about 10 degrees from vertical;
wherein the opening face has a slope in the range of about 35 degrees to about 55 degrees from vertical; and
wherein the sliding face has a slope in the range of about horizontal to about 5 degrees from horizontal.
8. The closure of claim 7 ,
wherein the closing face has a slope of about vertical;
wherein the opening face has a slope of about 45 degrees from vertical; and
wherein the sliding face has a slope of about horizontal.
9. The closure of claim 7 , wherein each of the closing face and the opening face is undercut with respect to the cover cap skirt to enhance the engagement between the cover cap teeth and the base cap teeth.
10. The closure of claim 1 , the cover cap teeth each further including recessed rear notches for reducing the amount of material required to make the cover cap and for improving molding of the cover cap teeth.
11. The closure of claim 1 , the cover cap top further comprising a centrally disposed opening for reducing the amount of material required to make the cover cap.
12. The closure of claim 1 , the vertical openings in the cover cap being small enough to prevent a child's fingers from accessing and turning the base cap independently from the cover cap, and being configured to permit the audible clicking sound to emit from the closure.
13. The closure of claim 1 , the support ring of the cover cap including a rim for engaging the bottom face of the base cap to inhibit removal of the cover cap from the base cap.
14. The closure of claim 13 , the rim protruding radially inwardly from the cover cap skirt.
15. A child-resistant container closure comprising:
a base cap having a top and a skirt depending downwardly from the top, the skirt including a plurality of asymmetric teeth formed in an outer wall of the skirt and recessed below the top, internal threads for engaging a neck of the container, and a bottom end, each of the teeth having a closing face sloped about 20 degrees from vertical, an opening face sloped about 30 degrees from vertical, and a sliding face disposed between the closing face and the sliding face and sloped about 6 degrees from horizontal, a junction between the closing face and the sliding face being disposed above a junction between the opening face and the sliding face; and
a cover cap having a top and a skirt depending downwardly from the top, the top including a plurality of asymmetrical downwardly extending teeth adapted for asymmetric engagement with the upwardly extending base cap teeth, the skirt having bottom end, an inwardly protruding raised ridge for centering the cover cap on the base cap, and a support ring protruding radially inwardly from the bottom end to engage with a ridge protruding radially outwardly from the bottom end of the base cap skirt to inhibit removal of the cover cap from the base cap, each of the cover cap teeth having a closing face sloped about vertical, an opening face sloped about 45 degrees from vertical, and a sliding face disposed between the closing face and the sliding face and sloped about horizontal;
wherein when the cover cap is rotated in a first direction, the cover cap teeth positively engage the base cap teeth to cause the base cap to rotate along with the cover cap in the first direction;
wherein when the cover cap is rotated in a second direction in combination with a predetermined downward force urging the cover cap top toward the base cap top, the cover cap teeth positively engage the base cap teeth to cause the base cap to rotate along with the cover cap in the second direction, the slope of the sliding faces of the base cap teeth ensuring that one of the cover cap teeth will drop into a notch between adjacent base cap teeth when the cover cap is rotated in the second direction; and
wherein when the cover cap is rotated in the second direction in the absence of the predetermined downward force, base cap remains nonrotating and the cover cap teeth slidably engage with the base cap teeth causing an audible clicking sound as pairs of teeth jump from one sliding engagement to another.
16. The closure of claim 15 , the cover cap skirt having a plurality of interspersed vertical legs each spaced apart from adjacent legs by vertical openings, the legs being joined by the support ring, the vertical openings in the cover cap being small enough to prevent a child's fingers from accessing and turning the base cap independently from the cover cap, and being configured to permit the audible clicking sound to emit from the closure.
17. The closure of claim 15 , wherein each of the closing face and the opening face of the base cap teeth is undercut with respect to the base cap skirt and wherein each of the closing face and the opening face of the cover cap teeth is undercut with respect to the respect to the cover cap skirt to enhance the engagement between the cover cap teeth and the base cap teeth.
18. The closure of claim 15 , the cover cap teeth each further including recessed rear notches for reducing the amount of material required to make the cover cap and for improving molding of the teeth.
19. The closure of claim 15 , the cover cap top further comprising a centrally disposed opening for reducing the amount of material required to make the cover cap.