The present invention relates generally to a closure for a container and particularly to a closure with means for indicating that the closure has been opened at least once.

There is an increasing demand for tamper-indicating systems which ensure that a container is not re-filled with non-original contents. Whilst it is relatively easy to produce some form of tamper-evidence, it is much more difficult to provide tamper-evidence which cannot be either overcome without causing the tamper-evidence system to activate, or activated and then returned to a visually identical state so as to appear non-activated.

A particularly useful method of providing tamper-evidence is to use a system in which a closure is initially located into a first position, but once removed can only be returned to a second position which is visually distinct from the first position. For example, US 5, 738, 231 describes a closure with a part which is moved during the opening process so that following opening it cannot pass back over a projection on the container finish. The result is that the closure can only return to a position in which it is axially displaced with respect to its original position. Document WO 02/096771 describes a closure with a first portion with inner and outer parts, and a second portion. Initially a section of the inner part of the first portion protrudes below the level if the second portion which is formed so as to have a reduced circumference. When the first portion is removed the section of the inner part is pulled from under the area of reduced circumference on the second portion. After removal the inner part of the first portion and the area of reduced circumference on the second portion retain their original dimensions, so that if the first portion is reapplied the inner part can no longer pass under the area of reduced circumference. The present invention provides a tamper-evident closure for a container, the closure comprising a first portion including inner and outer parts, and a second portion, the portions being provided with an outer shell which is separable info a first and second shell section, the first shell part being removable together with the inner and outer parts and the first portion being movable upon first opening from a first position in which the first and second shell parts are adjacent each other to a second position in which there is an unobstructed gap therebetween, the outer part comprising a collar rotatable relative to the inner part as the closure moves from the first to the second position and the first portion comprising locking means for irreversibly locking the closure in the second position upon first opening to prevent closing of the gap, the inner part including a line of weakness which breaks upon first opening to define a tamper- evident member visible in the gap in the second position.

If the inner part can move relative to the second portion before the outer part has reached its second position (to generate the gap) there Is a risk that the closure could be returned to a closed position without the gap having been generated. The present invention may be configured to prevent this.

The gap is unobstructed. By 'unobstructed' is meant there is no obstruction at or through the gap. The cfosure thereby does not rely on an obstructing member becoming trapped at or in the shell gap. By forming an unobstructed gap it is not possible to defeat the tamper-evidence by a simple cutting operation.

The closure comprises a shell. A metal (such as aluminium) shell cowl or the like may be provided to house the working components. The gap is formed in the shell. A frangible line may be provided in the shell, the gap being formed between adjacent peripheries of two shell parts along which the line extends.

The closure may further comprise a non-return valve. Certain industries, in particular the spirits industry, demand additional measures to prevent tampering. Jn-bore fitments such as non-return filments are often fitted to containers to prevent re-filling regardless of other tamper-evidence measures.

The closure may include a ratchet arrangement for locking the inner and outer parts in the second position. A ratchet arrangement is a simple and efficient method of irreversibly locking the inner and outer parts together. Advantageously the locking means which initially hold the inner part on the body may subsequently prevent, or help prevent, the outer part returning to the first position. The body part may include formations, such as screw threads, for engagement on the container or in-bore fitment as appropriate. In such cases the cap ratchet arrangement or other locking mechanism may be located above the formations so as to increase the difficulty in accessing and tampering with the locking arrangement. A section of the inner part defined by the line of weakness may remain with the second shell part and the second portion when the first shell part is removed. The tamper evident member may remain with the second shell part and the second portion when the first shell part is removed.

The locking means may comprise one or more ratchet members formed as projecting tabs. The ratchet tabs may be formed on the inner part.

The outer shell may comprise a line of weakness defining the first and second shell sections. The present invention also provides in combination a closure as described herein and a container.

The present invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a side elevation of a tamper-evident closure formed according to the present invention;

Figure 2 is a section of the closure of Figure 1 ;

Figure 3 is a perspective view of the working components of the closure of Figure 2; Figure 4 is a perspective view of an inner part of the working component of Figure 3; Figure 5 is a perspective view of an outer part of the working component of Figure 3;

Figure 6 is a perspective view of a second portion of the working component of Figure

3; and Figures 7a to 7d show the sequence of events during opening and reclosing of the closure of Figure 1.

Referring first to Figure 1 there is shown a tamper-evident closure generally indicated 10. The closure 10 has an outer shell 5 which is generally cup-shape, having a disc-shaped top plate 1 1 and a generally cylindrical tubular sidewall 12 depending from the periphery thereof. Below the top plate 1 1 , the sidewall 12 includes a plurality of longitudinally extending ribs forming a knurled region 13. Below the region 13 is a tuck-in bead 14 followed by two outward bulging shaped regions 15, 16 divided by a frangible line 17. The notch line 17 divides the shell into a first shell section 12a and a second shell section 12b. Below the region 16 is a further tuck-in bead 18 and the sidewall 12 terminates with an outwardly flared skirt 19 at its open end.

Referring now to Figure 2 the internal components of the closure 10 are shown. In brief, the components comprise an inner ratchet part 20, an outer ratchet part 21 which together with the inner part 20 forms a first portion; a snap-on body part 22 which forms a second portion and includes an upper flow regulating body part 23 and a lower attachment body part 24. The entire closure arrangement is fitted on to the neck of a glass bottle 25. Referring now to Figures 3 to 6 the inner working components of the closure are shown in more detail.

The inner ratchet part 20 is generally cup-shape, having a disc-shape top plate 30 and a tubular, generally cylindrical side wall 31 depending from the periphery thereof.

At the top of the side wall 31 where it meets the top plate 30 are a plurality of assembly drive dogs 32. Just below the drive dogs a pair of diametrically opposed anti-reset ratchet tabs 33 are provided. A ratchet guide slot 34 is provided in the sidewall and is upwardly open to be able to receive a corresponding drive dog member on the outer ratchet part 21. The guide slot 34 leads to an outer ratchet guide ramp 35. A pair of guide slots 34 and guide ramps is provided, one on either side of the sidewall 31. Towards the open end of the sidewall 31 an annular bead 36 is provided above a tamper-evident band 37 which is frangibly connected to a lower skirt 38 at the open end of the side wall 31.

As shown best in Figure 2, the interior of the sidewall 31 is provided with screw thread formations 39 for engaging corresponding screw threads on the second portion upper body. An annular ceiling plug 40 depends from the underside of the top plate 30 for engaging in the mouth of the second portion to seal it. The interior surface of the skirt 38 is provided with teeth 41 for engaging corresponding teeth on the second portion to prevent relative rotation. The teeth 41 also snap engage under a ring on the second portion so that axial movement is also prevented.

The outer ratchet part 21 is shown in more detail in Figure 5. The part 21 comprises a generally cylindrical collar open at both ends. The exterior of the collar 21 is provided with a plurality of anti-rotation ribs 45 which in use are engaged by the knurls 13 in the closure shell to prevent relative rotation. Below the ribs 45 is a tuck-in groove 46 which receives the tuck-in bead 14 on the closure shell. On the interior of the collar at the same end as the anti-rotation ribs is a plurality of anti-reset teeth 47 which engage the anti-reset tabs 33 on the inner ratchet part when the closure is moved to its second position to prevent it from being reset back to the first position as described in more detail below. The interior of the collar is also provided with a pair of drive dogs (not shown) which engage in the guide ramps 35 on the inner part in use and cause the outer part to rise up the side of the inner part during opening.

The second portion is shown in Figure 6. The second portion comprises a generally frusto-conical hollow body 22 with an upper thread-bearing portion 23 having external screw threads 50 for engaging the internal screw threads 39 on the inner part 20. Within the thread bearing portion 23 is positioned a dome-shape flow regulator 51. The regulator 51 is attached by three axial spokes 52 to the inner wall of the portion to provide a flow path around the regulator.

A ball chamber 53 is sized to accommodate the ball 55 in such a way that it can move freely.

A basket-retaining part 57 continues from the ball chamber 53. The internal bore of the basket-retaining part is increased by a step 58 at the bottom of the ball chamber. The increased bore is sized to accommodate the basket as described beiow. The neck-engaging part 24 depends from the basket retaining part. The neck-engaging part 24 has an external annular tuck-in groove 63 which is used to help hold the fitment on the container neck by virtue of the second rolled-in region 18 of the shell.

Below the groove 63 the internal surface of the part 24 includes a plurality of axial ribs for engaging ribs 70 on the container neck 25 as described below.

A window 72 is provided in the basket-retaining part 57. An identical window is present diametrically opposite (not shown). The windows 72 are present so that a sharp retention edge 73 can be formed in a moulding production process. The edge 73 provides a very strong connection under the lip 74 of the container neck 25. Between the windows 72 a plurality of teeth 77 extend and engage the inner part teeth 41 in use. The basket part 80 includes an annular upper part 81 sized so that it has an interference sealing fit within the basket-retaining part 57 of the pouring part 23. The internal diameter of the part decreases at the lower end of the upper part with a curved step and continues to form an annular plug part sized to fit sealingly into the internal bore of the container neck 25.

At the intersection of the step and the plug part a valve seat comprising a circular groove 82 extends radially inwardly and connects to a non-return valve comprising an upstanding hoop with the three internal spokes forming three generally triangular orifices. At the bottom of the annular upper part an inwardly curved sealing member 86 depends. The sealing member can flex upwardly towards the underside of the step and is positioned to seal against the upper surface of the container neck.

The float valve 85 comprises a disk-shape top plate with a cylindrical skirt depending from its periphery. The skirt is sized so that its open end fits into the groove of the basket part.

The closure 10 is assembled as follows.

The ball 55 is placed in the ball chamber 53. The float 85 is placed on the basket 80 and sits in the groove 82. The upper part of the basket 80 is pushed into the basket-retaining part 53 of the pouring part 23; the insertion extent is limited by the step 58.

The inner part 20 is screwed onto the body part 23 using the corresponding screw threads 39, 50. The plug part 40 enters the inner bore of the thread bearing portion 23. The outer part is connected to the inner part by pushing it down so that the outer part drive dogs engage into the guide ramps 35 via the slots 34. This achieves the working component arrangement shown in Figure 3.

The outer part, inner part, body part, ball, float valve and basket part are then added to the container neck by pressing the neck-engaging part 24 of the body part over the lip 74. The plug part of the basket enters the inner bore of the container neck until the sealing member contacts the upper surface of the container neck and the step clips under the lip. At this point the ribs on the neck and pouring part engage to prevent relative rotation. Engagement of the windows 72 onto the tip 74 prevents axiai movement. The teeth 41 snap fit under the ring 78.

The shell is now added. The shell sidewall is initially generally straight with the exception of the bulges 15, 16 and the flared skirt 19, which are preformed. Following placement over the rest of the tamper-evident arrangement the side wall is crimped into the groove 46 of the outer part and the groove 63 of the pouring part at points 14 and 18 respectively. The ribs are formed on the shell and lock into the ribs 45 on the outer part. The frangible line 1 7 is created approximately half way down the shell side wall by slitting to leave thin bridges.

The operation of the closure is as follows. From the starting, closed position of Figure 7a, initially the upper section 12a of the shell is grasped above the frangible line 17 and twisted. The upper section 12a cannot turn relative to the outer part 21 by the virtue of the ribs 13, 45. The body part cannot turn by virtue of the ribs 70 on the container neck and the neck-engaging part. The lower section 12b of the section of shell below the frangible line is firmly connected to the body part by crimped-in region 18, and also cannot turn. The inner part is prevented from turning relative to the pouring part at this stage because of the interaction of the ribs 41 , 77.

The upper section 12a of the shell turns and the frangible line 17 breaks. The turning of the upper section 12a turns the outer part 21 by virtue of the firm connection provided by the region 13 and the corresponding ribs 45.

The rotation of the outer part 21 causes its drive dogs to move up the guide ramps 35 until they reach the end of the ramps. During the rotation the teeth 47 are passing over the toothed tabs 33 and give an audible clicking sound. At the end of the ramps the outer part cannot be rotated further and cannot be rotated back because the teeth 47 cannot pass back over the tabs 33. Re-setting of the ratchet arrangement is thereby prevented. The tamper-evident arrangement is now shown in the position shown in Figure 7B. A gap (Gl ) is formed in a shell between the upper 12a and lower 12b shell sections. The gap (Gl ) is unobstructed; there is no obstacle at the point of dislocation to prevent closing of the gap (G l ). The band 39 is visible through the gap. When the outer part has finished rotating, continued rotation of the shell part 12a causes the inner part to rotate. This in turn causes the frangible line 39 to break as the part 20 unscrews from the second portion part 23. The inner part is completely unscrewed and the shell part 12a is removed together with the outer part 21 and the inner part with the exception of the skirt 38 which is retained under the ring 78 as shown in Figure 7c.

The closure therefore provides three opening events: i) breakage of the shell; ii) generation of the gap; iii) breakage of the inner part.

As shown in Figure 7d, when the upper shell section 12a is replaced and screwed back on the pouring part 175, the gap (G l ) cannot be re-closed because the outer part cannot rotate back relative to the inner port.