Closure cap with snap hinge and retaining ring

Abstract

The present invention concerns a closure ( 10 ) consisting of a cap portion ( 1 ), a retaining ring ( 3 ), a tear strip and a snap hinge ( 20 ), the snap hinge connecting the cap portion and the retaining ring in a single piece along a first circumferential section, wherein the cap portion ( 1 ) has a top plate ( 14 ) and the closure having overall a substantially cylindrical or slightly tapered closure skirt which, inter alia, comprises a substantially cylindrical cap skirt and the retaining ring ( 3 ), wherein the snap hinge ( 20 ) is integrated into the skirt and wherein the retaining ring ( 3 ) and the cap portion ( 1 ), in addition to being connected via the snap hinge ( 20 ), are also connected together along a second circumferential section ( 30 ) via the tear strip ( 4 ) which is also integrated into the skirt. To produce such a closure but at low cost and preferably using only a little material, and in particular to provide improved protection of the inside of the closure against environmental influences, the invention proposes that the cap skirt, tear strip, snap hinge and retaining ring together define an essentially closed closure skirt wherein the tear strip and the ends of the snap hinge ( 20 ) in the circumferential direction are connected with the cap skirt and/or the retaining ring and optionally with one another via film-like, easily tearable lines of weakness.

1 . A closure ( 10 ) consisting of a cap portion ( 1 ), a retaining ring ( 3 ), a tear strip and a snap hinge ( 20 ), the snap hinge connecting the cap portion and the retaining ring with one another in a single piece along a first circumferential section, wherein the cap portion ( 1 ) has a top plate ( 14 ) and the closure having overall a substantially cylindrical or slightly tapered closure skirt which, inter alia, comprises a substantially cylindrical cap skirt and the retaining ring ( 3 ), wherein the snap hinge ( 20 ) is integrated into the skirt and wherein the retaining ring ( 3 ) and the cap portion ( 1 ), in addition to being connected via the snap hinge ( 20 ), are also connected together along a second circumferential section ( 30 ) via the tear strip ( 4 ) which is also integrated into the skirt, characterized in that the cap skirt, tear strip, snap hinge and retaining ring together define an essentially closed closure skirt, wherein the tear strip and the ends of the snap hinge ( 20 ) in the circumferential direction are connected with the cap skirt and/or the retaining ring and optionally with one another via film-like, easily tearable lines of weakness. 
     
     
         2 . A closure according to  claim 1 , characterized in that the tear strip connects to both of the circumferential ends ( 21 ,  22 ) of the snap hinge ( 20 ) and extends over the entire remaining circumferential section of the closure skirt apart from the snap hinge. 
     
     
         3 . A closure according to  claim 1  or  claim 2 , characterized in that the tear strip with its end sections ( 5 ) bordering the snap hinge extends substantially to the upper rim of the snap hinge and preferably over its entire axial height. 
     
     
         4 . A closure according to one of  claims 1  to  2 , characterized in that the axial height of the tear strip is smaller than that of the snap hinge with the exception of its end sections bordering the snap hinge. 
     
     
         5 . A closure according to one of  claims 1  to  2 , characterized in that a tab grip of the tear strip which starts from one end section of the tear strip extends radially from the closure skirt and in the circumferential direction over the snap hinge and is retained close to the closure skirt by easily tearable tabs, preferably in the region of the snap hinge. 
     
     
         6 . A closure according to one of  claims 1  to  2 , characterized in that the upper rim of the tear strip runs near to the top plate ( 14 ) in the region thereof opposite to the snap hinge. 
     
     
         7 . A closure according to one of  claims 1  to  2 , characterized in that the snap hinge or a film hinge ( 6 ) of the snap hinge ( 20 ) is less than 2 mm, preferably less than 1 mm distant from the top plate ( 14 ). 
     
     
         8 . A closure according to one of  claims 1  to  2 , characterized in that in the cap skirt a recess ( 25 ) is provided on both sides of the snap hinge ( 20 ) which extends almost to the top plate, and is occupied by the end sections ( 5 ) of the tear strip. 
     
     
         9 . A closure according to one of  claims 1  to  2 , characterized in that a recess is provided in the cap skirt which extends almost to the top plate diametrically opposite to the snap hinge which, on the intact closure, is filled by the tear strip. 
     
     
         10 . A closure according to  claim 9 , characterized in that the recess diametrically opposite to the snap hinge extends over an angle between 20° and 60°, preferably between 30° and 40°. 
     
     
         11 . A closure according to  claim 8 , characterized in that the recesses ( 25 ) either side of the snap hinge extend over an angle between 5° and 20°, preferably between 7° and 15°. 
     
     
         12 . A closure according to  claim 8 , characterized in that the height of the cap skirt ( 1 ) measured in the axial direction in the region of at least one of the recesses ( 25 ) is reduced by at least half, preferably by at least 75% of the height of the regions outside the recesses and in particular to a distance of less than 1 mm from the inner surface of the top plate. 
     
     
         13 . A closure cap according to one of  claims 1  to  2 , characterized in that the snap hinge is formed from a sector of a substantially cylindrical or slightly tapered skirt between the top plate ( 14 ) and retaining ring ( 3 ), wherein said sector has two film hinges ( 6 ,  7 ) which are formed at an axial distance from each other by essentially circumferential lines of weakness and which, starting from a minimum axial separation approximately in the centre of the hinge sector, diverge towards the ends ( 21 ,  22 ) of the hinge ( 20 ) bordering the tear strip. 
     
     
         14 . A closure cap according to  claim 12 , characterized in that the lines of weakness ( 6 ,  7 ) are each in the form of an approximately circular or elliptical curve, the centres of which lie axially above or below the snap hinge ( 20 ). 
     
     
         15 . A closure according to one of  claims 1  to  2 , characterized in that the structures on the closure skirt and between the skirt sections have a radially shallow depth of less than 2 mm, preferably less than 1 mm. 
     
     
         16 . A closure according to one of  claims 1  to  2 , characterized in that the tear strip ( 4 ), over the major portion of the second circumferential sector apart from the snap hinge ( 20 ), is at a distance from the top plate which is at least double that distance in the sectors which are close to the top plate. 
     
     
         17 . A closure according to one of  claims 1  to  2 , characterized in that the distance of the tear strip from the top plate ( 14 ) in the sectors close to the top plate is at most 1 mm and outside these sectors is at least 2 mm. 
     
     
         18 . A closure according to one of  claims 1  to  2 , characterized in that the overall axial height of the closure is less than 15 mm, preferably at most 12 mm whereby, apart from the recesses, more than a third is taken up by the retaining ring and the cap skirt and somewhat less than a third is taken up by the tear strip. 
     
     
         19 . A closure cap according to one of  claims 1  to  2 , characterized in that in the region outside the recesses the cap skirt has an inwardly projecting retaining bead ( 12 ). 
     
     
         20 . A closure cap according to  claim 19 , characterized in that the radial thickness of the retaining bead in the regions furthest from the snap hinge is larger than that in a circumferential sector of approximately 180° centred on the snap hinge. 
     
     
         21 . A closure cap according to  claim 20 , characterized in that the maximum radial thickness of the retaining bead in the regions offset from the snap hinge by more than 90° is more than twice the radial thickness thereof in the 180° sector about the snap hinge. 
     
     
         22 . A closure cap according to  claim 20 , characterized in that the retaining bead has a radial thickness which, from a maximum value in the regions offset from the snap hinge by more than 90°, reduces in the direction of the retaining hinge continuously or stepwise to a minimum value which lies between a zero thickness and at most half the maximum thickness. 
     
     
         23 . A closure cap according to one of  claims 1  to  2 , characterized in that a tab grip which is connected with one end of the tear strip ( 4 ) extends parallel to the cylindrical cap skirt along the outside of the snap hinge ( 20 ) and is connected therewith via easily tearable connecting bridges. 
     
     
         24 . A closure cap according to one of  claims 1  to  2 , characterized in that a ring-shaped sealing web ( 18 ) extends from the top plate radially inwardly of the cap skirt ( 10 ). 
     
     
         25 . A closure cap according to  claim 24 , characterized in that the outside of the sealing web ( 18 ) carries a ring-shaped circumferential bead-like radial enlargement. 
     
     
         26 . A closure cap according to one of  claims 1  to  2 , characterized in that on its inner side and in the proximity of its lower rim the retaining ring ( 3 ) has an inwardly projecting retaining bead ( 9 ) or tapers downwardly.