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US4423820A Expired / Lapsed US ⏱️ 0.0 years remaining

Tamper proof closure and method of manufacturing same

Assignee: KLM COMPANY A CORP OF CT
•
Filing: 1982-03-01
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Granted: 1984-01-03
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Expires: 2002-03-01
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Abstract

Abstract A thermo-formed container closure having a breakaway ring including at least inwardly extending tab on the ring for engaging a lug on the container to prevent the ring from rotating as the closure top is unthreaded in which an annular flange joining the breakaway ring to the closure skirt wall is cut, except at a plurality of retaining bridges, with each of the bridges being of generally trapezoid shape and having a minimum area where the flange is attached to the closure skirt wall and a maximum area at the breakaway ring portion, to enhance the breakaway action as the ring is prevented from rotating.

Inventors

  • 👤 William Vangor

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 21:06
CPC Classifications
B; B65; B65D; B65D41/00; B65D41/32; B65D41/34; B65D41/3404; B65D41/3409

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 203 words
A closure thermoformed from a sheet of plastic material to have a top, a skirt wall having one end depending from said top, an annular, generally horizontal flange having one edge attached to the other end of said skirt wall, a breakaway ring depending downwardly from said other edge of said flange, said flange being cut therearound to form a major cut line through the flange and a plurality of bridges which hold the ring to the flange, each of said bridges being generally trapezoidal in shape with two generally parallel sides, one being narrower than the other and two ends joining said sides with the ends diverging in generally opposite directions from said narrow side, the narrow side of each bridge facing and connected to the skirt wall and the other wider side facing and connected to the breakaway ring, and at least one tab on said breakaway ring adapted to engage a lug on the container to which the closure is fastened when the closure is unfastened by rotation in a first direction, the continuing rotation of the closure in said first direction causing the ring to lock and the bridges to fracture whereby the breakaway ring separates from the closure.
Claim 2
Dependent Claim 203 words
A closure thermoformed from a sheet of plastic material to have a top, a skirt wall having one end depending from said top, an annular, generally horizontal flange having one edge attached to the other end of said skirt wall, a breakaway ring depending downwardly from said other edge of said flange, said flange being cut therearound to form a major cut line through the flange and a plurality of bridges which hold the ring to the flange, each of said bridges being generally trapezoidal in shape with two generally parallel sides, one being narrower than the other and two ends joining said sides with the ends diverging in generally opposite directions from said narrow side, the narrow side of each bridge facing and connected to the skirt wall and the other wider side facing and connected to the breakaway ring, and at least one tab on said breakaway ring adapted to engage a lug on the container to which the closure is fastened when the closure is unfastened by rotation in a first direction, the continuing rotation of the closure in said first direction causing the ring to lock and the bridges to fracture whereby the breakaway ring separates from the closure.
Claim 3
Dependent Claim 44 words
A closure as in claim 1 wherein the ends of said bridges are cut at an angle through the thickness of said flange such that there is more material for the bridge at the lower surface of said flange than at the upper surface.
Claim 4
Dependent Claim 22 words
A closure as in claim 2 wherein the angled cuts of the ends of the bridge through the flange is generally straight.
Claim 5
Dependent Claim 36 words
A closure as in claim 2 wherein the ends of each bridge extend to and make substantially equal angles with the major cut line of the flange, but are of opposite direction relative the skirt wall.
Claim 6
Dependent Claim 24 words
A closure as in claim 4 wherein each end of a bridge intersects the major cut line of the flange at an acute angle.
Claim 7
Dependent Claim 36 words
A closure as in claim 1 wherein the ends of each bridge extend to and make substantially equal angles with the major cut line of the flange, but of opposite direction relative to the skirt wall.
Claim 8
Dependent Claim 24 words
A closure as in claim 6 wherein each end of a bridge intersects the major cut line of the flange at an acute angle.
Claim 9
Dependent Claim 28 words
A closure as in claim 1 where a said tab is cut on at least two joining edges and is formed to extend inwardly of said breakaway ring.
Claim 10
Dependent Claim 27 words
A closure as in claim 8 when said tab is cut at only two joining edges to form a corner for engaging a lug on the container.
Claim 11
Dependent Claim 24 words
A closure as in claim 1 further comprising means on said skirt wall adapted for fastening the closure to mating means of a container.
Claim 12
Independent Claim 155 words
A method for forming a safety closure comprising the steps of thermo-forming the closure from a sheet of plastic material to have a top, a skirt wall depending downwardly from said top, an annular flange extending outwardly from the lower end of said skirt wall and a breakaway ring extending downwardly from said flange, forming at least one radially inwardly extending tab on said breakaway ring for engaging a projection on the container to prevent rotation of the ring as the closure is being unfastened, and cutting said flange therearound to form a plurality of bridges of generally trapezoidal shape having two generally parallel sides with one being narrower than the other and two ends joining said sides with the ends diverging in generally opposite directions from said narrow side, with the narrow side of the trapezoid facing toward and connected to said skirt wall and the wider side facing and connected to said ring.
Claim 13
Independent Claim 155 words
A method for forming a safety closure comprising the steps of thermo-forming the closure from a sheet of plastic material to have a top, a skirt wall depending downwardly from said top, an annular flange extending outwardly from the lower end of said skirt wall and a breakaway ring extending downwardly from said flange, forming at least one radially inwardly extending tab on said breakaway ring for engaging a projection on the container to prevent rotation of the ring as the closure is being unfastened, and cutting said flange therearound to form a plurality of bridges of generally trapezoidal shape having two generally parallel sides with one being narrower than the other and two ends joining said sides with the ends diverging in generally opposite directions from said narrow side, with the narrow side of the trapezoid facing toward and connected to said skirt wall and the wider side facing and connected to said ring.
Claim 14
Dependent Claim 45 words
The method of claim 11 wherein the step of cutting the bridges further comprises making the cuts for the ends of the bridge at an angle such that the bridge has a decreasing amount of material from the top to the bottom of the flange.

References Cited (Backward Citations)

US4153174A Cited
US4225050A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-01-02 1987-07-04 1988-01-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-01-02 1991-07-04 1992-01-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-01-02 1995-07-04 1996-01-03 $7700.00 Window Closed / Lapsed

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