GB1598303A - Closure cap - Google Patents

Description

(54) CLOSURE CAP (71) We, MARTIN BRIAN ABLEY of 12 North Leech, Lancaster Park, Morpeth, Northumberland, ALAN BRIAN CAR TER of 119 Tolmers Road, Cuffley, Hertfordshire, both British subjects and Strollcroft Limited, a British company of 45 High Street, Harpenden, Hertfordshire, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:: This invention relates to a closure cap for containers, such as containers for liquids or powdered materials, which will provide an indication of whether or not the cap has been removed from a container after its initial fitting, and so will provide a means of allowing a customer, purchasing material in such a container, to ascertain that prior to his purchase of the same the cap has not been removed and part of the contents pilfered.

Closure caps of this kind are known, particularly made of metal, in which the cap is screwed onto a spout or collar provided on the container, the cap having at its rim a flange bent around a ridge on the neck or collar, the cap having a line of perforations or slits there around between said flange and the remainder of the cap, establishing a weakened connection between the flange and the remainder of the cap. To remove the cap, since it is impossible to remove the flange from the spout or collar, it is necessary to break the connection between the flange and the remainder of the cap, this being done simply by unscrewing the cap, thereby producing an axial tension which breaks the material between adjoining perforations or slits.However, in practice, on unscrewing the cap, the flange does not generally break off at the same time all around the cap and frequently remains attached at one point to the cap so that as the cap is unscrewed it is pulled out of alignment with the spout or collar and may become jammed or the screw may be damaged making it impossible to replace the cap satisfactorily. Furthermore, special equipment is required to fit a cap of this kind initially and the expense of such equipment may not be justifiable in many applications.

Closure caps of the kind to which the present invention relates are also known, particularly for small bottles, in which the cap is of flexible plastics and substantially a push-on cap, the rim of which is held captive on a bottle neck and is connected at one point around its circumference to the remainder of the cap by a hinge portion of the plastics material and is connected with the remainder of the cap around the remainder of its circumference by a strip of the plastics material which strip is connected to the rim and the remainder of the cap along lines of weakening, the strip having a gripping tag by means of which the strip can be torn away from the remainder of the cap leaving the closure thereafter hingeably connected with the rim and thus with the bottle.

Such a cap has the disadvantage that it requires special equipment to apply.

It is an object of the present invention to provide an improved pilfer proof cap for a container.

According to one aspect of the invention, there is provided a closure cap for a container, the cap comprising an end wall, a skirt extending from the end wall and including a first part, nearer said end wall, which is internally threaded to allow the cap to be screwed onto a corresponding externally screw-threaded neck or collar of a container, and a second part, further from said end wall, which provides the rim of the cap and which provides, at the rim of the cap, an internal rib providing an abutment face facing generally axially towards the interior of the caP, the external diameter of said first part of the skirt at its portion furthest from said end wall being less than the internal diameter of said second part of the skirt at its portion nearest said end wall and said weakened frangible connection comprising a plurality of ribs distributed around the cap and each extending between the first and second part of the cap, at least the portion of said second part which adjoins said first part having a break in its circumference and a gripping tag immediately adjacent said break, whereby at least said portion of said second part forms a tear-strip which can be gripped and torn from said first part along said frangible connection.

Preferably said internal rib also provides an axially sloping ramp face, diverging towards the open end of the cap.

According to another aspect of the invention there is provided the combination of a closure cap according to the first mentioned aspect with a container having a neck or collar providing an opening into the container, said neck or collar having an external screw thread engaged by the internal screw thread of the cap, the neck or collar being provided, at a position spaced further than said screw-threaded portion from said opening, with an external annular rib providing an abutment face opposing the abutment face on the internal rib of the closure cap, at least one of said annular ribs providing an axially sloping ramp face which converges towards the common axis of the neck or collar and the cap in a direction which corresponds to the direction of the open end of the neck or collar and the closed end of the cap, when the cap is fitted to the neck or collar.

A cap according to the invention having the preferred features noted can be fitted to a complementary neck or collar of a container forming the other part of said combination simply by screwing the cap onto the neck or collar till the sloping ramp face on the internal rib of the cap engages the corresponding ramp face on the external rib on the neck or collar, and screwing the cap down further so that the portion of the cap providing said internal rib expands resiliently to allow the internal rib of the cap to pass the rib on the neck or collar and then snaps back behind the rib on the neck or collar.

Thereafter, engagement of the abutment face of the rib on the cap with the abutment face of the rib on the collar prevents the rib on the cap from passing that on the collar so that the closure can only be removed by severing the connection between the screwthreaded portion of the cap and the portion providing said internal rib.

It will be evident that if desired a sloping ramp face need be provided on only one of said ribs, i.e. only on the internal rib on the cap or only on the external rib on the cap or closure.

The internal rib may be provided in said tear strip, or alternatively the part of the cap providing the internal rib may be connected via a line of weakening to said tear strip, said tear strip being in turn connected via a line of weakening to the remainder of cap.

In the latter case, once the tear strip has been removed, the portion of the cap providing the internal rib remains captive on the neck providing an indication that the container has been opened.

Other preferred features of the invention will appear from the following description, given by way of example, of several embodiments, with reference to the accompanying drawings in which: Figure I is a view in axial section along line of A-A of Figure 2, of a closure cap forming one embodiment of the invention, Figure 2 is a schematic plan view of the cap- of Figure 1, Figure 3 is a perspective view of the cap of Figures 1 and 2, Figure 4 is a view in axial section showing the cap of Figures 1 to 3 fitted to a complementary container neck, Figure 5 is a fragmentary view, in axial section showing the cap of Figures 1 to 3 fitted to a variant container neck, Figure 6 is a perspective view of another embodiment of closure cap, and Figure 7 is a partial view in axial section of the cap of Figure 6.

Referring to Figures 1 to 4, the cap, moulded in synthetic plastics, comprises a main portion 10 providing an end wall 12 and a cylindrical or slightly frusto-conical skirt 14 connected along its edge remote from the end wall 12, via a weakened frangible connection, with an edge of a further portion 16 formed as a tear strip or band curled into a substantially annular form. One circumferential end of the band 16 is formed as a gripping tag 17 projecting outwardly from the cap, but apart from this and the short gap between the adjacent circumferential ends of the band 16, the latter is substantially annular and is substantially cylindrical on its exterior, the portion of the band 16 nearer end wall 12 being also cylindrical internally while the portion of the band 16 further from end wall 12 provides an internal annular rib 18.

The upper edge of the substantially cylindrical wall provided by the upper portion of band 16 is spaced radially outwardly from the lower annular edge of the skirt 14, but is connected thereto by narrow bridges 20 at intervals around the cap. As shown in Figure 3, the exterior of the skirt 14 is provided with vertical ribs 22 at intervals therearound, and each bridge 20 is provided at the foot of a respective rib 22. In the embodiment shown the ribs 22 merge with the frusto-conical exterior of the cap at their feet, but if preferred, the ribs may stand proud of the cap over their whole length and the bridges connecting the band 16 with the skirt may simply be formed by the junction of the lower ends of the ribs with the band 16.The bridges 20 provide a weakened connection between the band 16 and the skirt 14, and may be ruptured by gripping the tag 17 and tearing off the band 16.

The skirt 14 is internally screw-threaded, as indicated at 24, so that the cap can be screwed onto a complementary container neck indicated at 26 in Figure 4.

It will be noted that the rib 18 is substantially wedge shaped in axial section providing an abutment face 28 facing in the axial direction away from the open end of the complete cap and towards the end wall 12, and a sloping, generally frusto-conical ramp face 30 diverging outwardly from the position of face 28 to the open end of the complete cap (provided by the lower edge of band 16). The smallest internal diameter of the rib 18 is of course greater than the greatest root diameter of the internal screw thread 24.

The container of which the neck is indicated at 26 in Figure 4 is also preferably of plastics and the neck 26 includes an upper, generally cylindrical portion screw-threaded externally to engage the thread 24, and below this upper portion an annular rib 32 of enlarged diameter, and so dimensioned as to fit freely within the space defined within the upper portion of band 16 between the lower edge of the skirt 14 and the rib 18.

At its lower edge, the rib 32 terminates in an abutment face 34 facing axially away from the open end of the neck 26 and engaging the abutment face 28 of rib 18. The rib 32 tapers slightly upwardly and at its upper edge is of a diameter smaller than the greatest diameter of ramp face 30 (i.e. the diameter of face 30 at the open end of the complete cap).

The cap can be fitted to the neck 26 simply by screwing the cap on until the upper edge of rib 32 engages ramp face 30, and screwing the cap on further so that by the wedging action of the face 30, the rib 16 is forced to expand resiliently outwardly so that the rib 18 can pass the rib 32, the rib 18 snapping resiliently in again below the rib 32. The end wall 12 is dished inwardly as shown and is made thin enough to be flexible, so that as the cap is screwed fully on, the end wall 12 engages the rim of the container neck as shown, flexing to adapt to any misalignment of the rim of neck 26 and maintaining an effective seal therewith by reason of its resilient deformation. Thus the need for a sealing insert, such as a cork or cardboard disc, is avoided.

Once the cap has been fitted to the neck 26, it cannot simply be unscrewed again since this is prevented by engagement of abutment face 28 with abutment face 34.

The cap can only be removed after the band 16 has been torn off by means of the tag 17.

Figure 5 shows an alternative form of rib 32 on the neck 26, the rib 32 in this case beinhg substantially wedge-shaped in crosssection, presenting, on its side opposite the abutment face 34, a conically sloping ramp face 36, of substantially the same slope as the ramp face 30 of rib 18. The ramp face 36 thus also contributes to the outward wedging action applied to the rib 18 during fitting of the cap, and indeed, with a rib 32 of the form shown in Figure 5 on the container neck, it is not strictly necessary to provide a sloping wedging surface on the rib 18.

Figures 6 and 7 show a variant of the cap of Figures 1 to 4. Corresponding parts in Figures 6 and 7 have the same reference numerals as in Figures 1 to 4. The principal difference between this cap and that of Figures 1 to 4 is that in the embodiment of Figures 6 and 7 the band 16, providing the rib 18, is in the form of an unbroken annulus and is not connected directly with the skirt 14 but instead is connected to an intermediate tear strip 16' which in turn is connected with the skirt 14. The tear strip 16', like the strip 16 in in Figures 1 to 4, has its opposite ends closely adjacent but spaced apart circumferentially and has at one end a gripping tag 17, shown as having a different form from that in Figures 1 and 2, but which may if preferred, be of the same form.The strip 16' is connected to the skirt 14 by narrow frangible bridges 20, in the same way as the strip 16 in Figures 1 to 4 is connected with the skirt 14, and the band 16 is connected to the strip 16' in the same way, by narrow frangible bridges 20, as shown in Figure 7.

The cap of Figures 6 and 7 is applied to a complementary container neck in the same way as the cap of Figures 1 to 4, and can only be unscrewed after tearing off the strip 16'. In this case however, the band 16 remains captive on the container neck giving a clear indication that the cap has been removed after its initial fitting.

WHAT WE CLAIM IS: 1. A closure cap for a container, the cap comprising an end wall, a skirt extending from the end wall and including a first part, nearer said end wall, which is internally threaded to allow the cap to be screwed onto a correspondingly externally screwthreaded neck or collar of a container, and a second part, further from said end wall, which provides the rim of the cap and which provides, at the rim of the cap, an internal rib providing an abutment face facing generally axially towards the interior of the cap,

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (12)

**WARNING** start of CLMS field may overlap end of DESC **. embodiment shown the ribs 22 merge with the frusto-conical exterior of the cap at their feet, but if preferred, the ribs may stand proud of the cap over their whole length and the bridges connecting the band 16 with the skirt may simply be formed by the junction of the lower ends of the ribs with the band 16. The bridges 20 provide a weakened connection between the band 16 and the skirt 14, and may be ruptured by gripping the tag 17 and tearing off the band 16. The skirt 14 is internally screw-threaded, as indicated at 24, so that the cap can be screwed onto a complementary container neck indicated at 26 in Figure 4. It will be noted that the rib 18 is substantially wedge shaped in axial section providing an abutment face 28 facing in the axial direction away from the open end of the complete cap and towards the end wall 12, and a sloping, generally frusto-conical ramp face 30 diverging outwardly from the position of face 28 to the open end of the complete cap (provided by the lower edge of band 16). The smallest internal diameter of the rib 18 is of course greater than the greatest root diameter of the internal screw thread 24. The container of which the neck is indicated at 26 in Figure 4 is also preferably of plastics and the neck 26 includes an upper, generally cylindrical portion screw-threaded externally to engage the thread 24, and below this upper portion an annular rib 32 of enlarged diameter, and so dimensioned as to fit freely within the space defined within the upper portion of band 16 between the lower edge of the skirt 14 and the rib 18. At its lower edge, the rib 32 terminates in an abutment face 34 facing axially away from the open end of the neck 26 and engaging the abutment face 28 of rib 18. The rib 32 tapers slightly upwardly and at its upper edge is of a diameter smaller than the greatest diameter of ramp face 30 (i.e. the diameter of face 30 at the open end of the complete cap). The cap can be fitted to the neck 26 simply by screwing the cap on until the upper edge of rib 32 engages ramp face 30, and screwing the cap on further so that by the wedging action of the face 30, the rib 16 is forced to expand resiliently outwardly so that the rib 18 can pass the rib 32, the rib 18 snapping resiliently in again below the rib 32. The end wall 12 is dished inwardly as shown and is made thin enough to be flexible, so that as the cap is screwed fully on, the end wall 12 engages the rim of the container neck as shown, flexing to adapt to any misalignment of the rim of neck 26 and maintaining an effective seal therewith by reason of its resilient deformation. Thus the need for a sealing insert, such as a cork or cardboard disc, is avoided. Once the cap has been fitted to the neck 26, it cannot simply be unscrewed again since this is prevented by engagement of abutment face 28 with abutment face 34. The cap can only be removed after the band 16 has been torn off by means of the tag 17. Figure 5 shows an alternative form of rib 32 on the neck 26, the rib 32 in this case beinhg substantially wedge-shaped in crosssection, presenting, on its side opposite the abutment face 34, a conically sloping ramp face 36, of substantially the same slope as the ramp face 30 of rib 18. The ramp face 36 thus also contributes to the outward wedging action applied to the rib 18 during fitting of the cap, and indeed, with a rib 32 of the form shown in Figure 5 on the container neck, it is not strictly necessary to provide a sloping wedging surface on the rib 18. Figures 6 and 7 show a variant of the cap of Figures 1 to 4. Corresponding parts in Figures 6 and 7 have the same reference numerals as in Figures 1 to 4. The principal difference between this cap and that of Figures 1 to 4 is that in the embodiment of Figures 6 and 7 the band 16, providing the rib 18, is in the form of an unbroken annulus and is not connected directly with the skirt 14 but instead is connected to an intermediate tear strip 16' which in turn is connected with the skirt 14. The tear strip 16', like the strip 16 in in Figures 1 to 4, has its opposite ends closely adjacent but spaced apart circumferentially and has at one end a gripping tag 17, shown as having a different form from that in Figures 1 and 2, but which may if preferred, be of the same form.The strip 16' is connected to the skirt 14 by narrow frangible bridges 20, in the same way as the strip 16 in Figures 1 to 4 is connected with the skirt 14, and the band 16 is connected to the strip 16' in the same way, by narrow frangible bridges 20, as shown in Figure 7. The cap of Figures 6 and 7 is applied to a complementary container neck in the same way as the cap of Figures 1 to 4, and can only be unscrewed after tearing off the strip 16'. In this case however, the band 16 remains captive on the container neck giving a clear indication that the cap has been removed after its initial fitting. WHAT WE CLAIM IS:

1. A closure cap for a container, the cap comprising an end wall, a skirt extending from the end wall and including a first part, nearer said end wall, which is internally threaded to allow the cap to be screwed onto a correspondingly externally screwthreaded neck or collar of a container, and a second part, further from said end wall, which provides the rim of the cap and which provides, at the rim of the cap, an internal rib providing an abutment face facing generally axially towards the interior of the cap,

the external diameter of said first part of the skirt at its portion furthest from said end wall being less than the internal diameter of said second part of the skirt at its portion nearest said end wall and said weakened frangible connection comprising a plurality of ribs distributed around the cap and each extending between the first and second part of the cap, at least the portion of said second part which adjoins said first part having a break in its circumference and a gripping tag immediately adjacent said break, whereby at least said portion of said second part forms a tear-strip which can be gripped and torn from said first part along said frangible connection.

2. A closure cap according to claim 1 wherein said internal rib provides an axially sloping ramp face, diverging towards the open end of the cap.

3. A closure cap according to claim 1 or claim 2, wherein the internal rib is provided in said tear strip.

4. A closure cap according to claim 1 or claim 2 wherein the portion of the cap providing the internal rib is connected via a line of weakening to an adjoining portion of the cap forming the tear strip, said adjoining portion of the cap being connected in turn, via a further line of weakening, to the screw-threaded, remaining, first part of the cap. A

5. A closure cap according to any preceding claim wherein the end wall of the cap is dished inwardly and is made thin enough to be flexible whereby it can adapt to the rim of a container neck to which the cap is screwed in use and provide an effective seal.

6. The combination of a closure cap according to any preceding claim with a container having a neck or collar providing an opening into the container, said neck or collar having an external screw thread engaged by the internal screw-thread of the cap, the neck or collar being provided, at a position spaced further than said screwthreaded portion from said opening, with an external annular rib providing an abutment face opposing the abutment face on the internal rib of the closure cap, at least one of said annular ribs providing an axially sloping ramp face which converges towards the common axis of the neck or collar and the cap in a direction which corresponds to the direction of the open end of the neck or collar and the closed end of the cap, when the cap is fitted to the neck or collar.

7. A combination according to claim 6, wherein said internal annular rib in the cap provides such an axially sloping ramp face which thus diverges away from the axis of the cap in the direction away from the abutment face provided by said rib in the collar and towards the open end of the cap.

8. A combination according to claim 7 wherein the external annular rib on the neck or collar also provides an axially sloping ramp face converging towards the axis of the neck or collar from the abutment face provided by the rib on the neck or collar towards the open end of said neck or collar.

9. A closure cap substantially as hereinbefore described with reference to, and as shown in, Figures 1 to 4 of the accompanying drawings.

10. A closure cap substantially as hereinbefore described with reference to, and as shown in, Figures 6 and 7 of the accompanying drawings.

11. The combination of a container having a neck with a closure substantially as hereinbefore described with reference to, and as shown in, Figure 4 of the accompanying drawings.

12. The combination of a container having a neck with a closure substantially as hereinbefore described with reference to, and as shown in, Figure 5 of the accompanying drawings.