Press-on, twist-off bottle cap

Claim 2

A closure cap for application to a bottle or the like, said cap comprising: a top panel with a generally cylindrical skirt depending therefrom and terminating downwardly in a circular lowErmost edge, at least that portion of said skirt which extends from a first plane below said panel to said edge being formed of sheet material of substantially uniform single thickness, said skirt portion being corrugated so as to define a circumferential series of straight outward ridges and straight flutes therebetween extending from said first plane to a second plane spaced from said edge, the crests of said ridges and the outer surface of said skirt from said second plane to said edge lying on a common substantially cylindrical surface.

Claim 3

The invention as defined in claim 1, said corrugated skirt portion being sized for constriction about external thread formations on the finish of a bottle so as to deform inward portions of said material along the lines of said flutes over and about portions of the thread formations and thereupon to form female thread elements in said skirt conforming to the external thread formations.

Claim 4

The invention as defined in claim 2, the depth of said flutes being approximately the same as the depth of the external thread formations, whereby, subsequent to said constriction, the outside diameter of said skirt across the major diameter of said thread elements will be substantially the same as the diameter of said cylinder.

Claim 5

The invention as defined in claim 3, the depth of said flutes being greater than the thickness of said material, whereby upon generally uniform said constriction of the entire said skirt below said first plane, the inside diameter of said skirt between said second plane and said edge will be not less than the major diameter of the external thread formations.

Claim 6

The invention as defined in claim 1, said skirt being weakened around a circle in a plane between said second plane and said edge.

Claim 7

The invention as defined in claim 5, said cap being adapted for application to a bottle having a downwardly facing external shoulder below the thread formations on the finish, said skirt being of such length that a lip portion thereof below said circle of weakening will extend below the shoulder when said cap is applied to the bottle, whereby said lip portion can be formed into engagement with the shoulder so as to form a tamper-proof closure for the bottle.

Claim 8

A twistably removable closure cap for engaging external thread formations on the finish of a bottle or the like, said cap comprising: a top panel and a generally cylindrical skirt depending therefrom and terminating downwardly in an edge, at least that portion of said skirt which extends from a first plane below said panel to said edge being formed of sheet material of substantially uniform single thickness, said skirt being corrugated so as to define straight outward ridges extending from said first plane to a second plane spaced from said edge, there being flutes between said ridges, portions of said skirt along the lines of said flutes being conformed to elements of the external thread formations so as to define female thread elements between said ridges, the crests of said ridges and a circumferential band of said skirt immediately downward of said second plane being elements of a hollow cylinder having an inside diameter not substantially less than the major diameter of the external thread formations, the other portions of said skirt below said first plane lying substantially within the outside diameter of said cylinder.

Claim 9

A twistably removable closure cap for engaging external thread formations on the finish of a bottle or the like, said cap comprising: a top panel and a generally cylindrical skirt depending therefrom and terminating downwardly in an edge, at least that portion of said skirt which extends from a first plane below said panel to said edge being formed of sheet material of substantially uniform single thickness, said skirt being corrugated so as to define straight outward ridges extending from said first plane to a second plane spaced from said edge, there being flutes between said ridges, portions of said skirt along the lines of said flutes being conformed to elements of the external thread formations so as to define female thread elements between said ridges, the crests of said ridges and a circumferential band of said skirt immediately downward of said second plane being elements of a hollow cylinder having an inside diameter not substantially less than the major diameter of the external thread formations, the other portions of said skirt below said first plane lying substantially within the outside diameter of said cylinder.

Claim 10

The invention as defined in claim 7, said ridge crests and the crests of said female thread elements being rounded, the outside diameter of said skirt across the major diameter of said female thread elements being substantially equal to the outside diameter of said cylinder, said ridges, said thread elements and said band thereby defining a grid around said skirt adapted to shield said edge and to afford a sure and comfortable finger grip for twisting said cap off and on said finish.