A SELF-CLOSING CLOSURE

Abstract: A self-closing closure assembly (13) for a container (11) of particulate material, e.g. talcum powder, and comprising a closure body (14) having a part spherical external surface (30) in which at least one aperture (33) is provided for dispensing powder from the container, a cover (15) mounted on the closure body (14) and having a part spherical inner surface (42) that is slidable over the external surface (30) between an aperture-closed position, and an aperture-open position, and biasing means (16) formed integrally with one of the cover (15) and body (14) to urge the cover towards the closed position. The cover (15) may be provided with a tamper-evident stop (52).

Description: A SELF-CLOSING CLOSURE TECHNICAL FIELD This invention relates to a closure, and in particular to a self-closing closure for a container, and to a container provided with such a closure. BACKGROUND ART A typical known container for talcum powder has a closure comprising a closure body which fits over the mouth of the container and is provided with a plurality of spaced apart through holes, and a cover which either has a plurality of through holes or a large aperture therein. The cover is turnable relative to the closure body so that the holes or aperture in the cover, in an open condition, align with holes in the body to allow powder to escape, and, in a closed condition, block the holes in the body to close the container. This known type of container, once in the open condition, remains open unless deliberately closed by the user. This can cause problems, especially with very young children or babies who, if they come upon an open container of talcum powder, are liable to handle the container and create a mess or even accidentally cause powder to be spilled into their own faces giving rise to breathing problems. Self-closing dispensing containers are known from EP- B-195,812 and EP-A-323,288. A container of this known type is generally used for containing pills and has a co¬ operating sliding closure that slides transversely of the mouth of the container and is biased into a closed position by biasing means acting directly between the container and the closure. DISCLOSURE OF THE INVENTION The present invention seeks to provide a self-closing closure for a container which does not utilise the container as a part of the self-closing mechanism, and which can be operated by a single hand. According to the present invention there is provided a self-closing closure assembly for a container of particulate material, e.g. powder, comprising a closure body for attachment to the mouth of the container, the body having a part spherical external surface in which at least one aperture is provided for dispensing material from the container, a cover mounted on the closure body and having a part spherical inner surface that is slidable over said part-spherical external surface between an aperture-closing first position and an aperture-opening second position, and biasing means formed integrally with one of the cover and body to act against the other of the cover and body to urge the cover towards said first position. The closure is preferably a snap-fit over the mouth of the container but could be fitted onto the container by any other suitable means, e.g. by screw means. Preferably the biasing means is formed integrally with the cover and suitably comprises a leaf spring which is located in a cavity formed between the closure body and the cover. Preferably, the closure cover is pivotally mounted on the closure body for movement between its first and second positions. The cover and biasing means, e.g. a spring, of the closure assembly are conveniently moulded from resilient plastics material, e.g. polyethylene, polypropylene, nylon etc. The biasing means, e.g. a leaf spring, may be moulded integrally with either the closure body or the cover. Preferably said part-spherical external surface comprises a recess within a larger diameter part-spherical second surface and said cover is slidable within the recess. Shoulders extend between the spherical surfaces with some acting as abutments limiting movement of the cover at the first and second positions, and other shoulders acting as guides for the sliding movement of the cover relative to the body. Preferably the cover is initially prevented from moving from said first position to said second position by a detachable tamper-evident stop or device. Such a tamper- evident device may also serve as a child-proof device to prevent very young children from initially opening the closure assembly. A closure assembly according to the invention may be used for containers which store and dispense fine particulate materials, for example talcum powder. BRIEF DESCRIPTION OF DRAWINGS Embodiments of the invention will now be described, by way of example only, and with particular reference to the accompanying drawings, in which:- Figure 1 and Figure 2 are schematic part-sectional views of a container with a closure assembly according to the invention shown in closed and open conditions, respectively; Figure 3 is a side elevation of the closure assembly shown in Figures 1 and 2; Figure 4 is a cross-sectional view of the closure assembly shown in Figures 1 and 2; Figure 5 is a front elevation of a cover of the closure assembly; Figure 6 is a sectional view taken on the line VI-VI of Figure 5; Figure 7 is a side elevation of a body of the closure assembly; Figure 8 is a rear elevation of the body; Figure 9 is a partial plan of the body showing its dispensing apertures; Figure 10 is an isometric view of a closure assembly, as shown in Figure 3, with a tamper evident device on a container; and Figure 11 is an enlarged cross-sectional view through the cover and tamper-evident device shown in Figure 10. BEST MODES FOR CARRYING OUT THE INVENTION Figures 1 and 2 show part of a container 11 depicted in cross-section. The container 11 may be made from any suitable material such as glass, cardboard, metal or plastics. Typically, however, the container 11 comprises a blow moulded plastics material container 11 for use in the storage and dispensing of talcum powder, or other powder or particulate material. The container 11 has a generally circular cylindrical neck or mouth 12 closed by a closure assembly generally designated 13. The closure assembly 13 comprises a closure body 14, a closure cover 15 and biasing means in the form of spring means 16. The closure body, cover and spring means may all be moulded from a resilient plastics material. The closure body 14 has a cylindrical skirt 17 which is push fitted over the mouth 12 of the container 11 and has a radially inwardly projecting rib 18 on its inner surface that makes a snap fit connection with the container, although any other suitable connection, e.g. a screw connection or 'push-on' connection could be employed if desired. The closure body 14 is substantially part hemi¬ spherical and its equatorial region extends into the cylindrical skirt 17 having the internally projecting rib 18 which provides the snap-fit connection over an outwardly projecting annular rib 28 adjacent the mouth 12 of the container 11 so as to secure the closure assembly 13 to the container. With reference to Figures 7-9, the hemi-spherical body 14 has a recess 29 formed in its part-spherical outer surface 27. The recess 29 is substantially rectangular as viewed in Figures 8 and 9 and has a smaller diameter part- spherical base surface 30 surrounded by side shoulders 31,32 and end shoulders 34,35, which connect the two surfaces 27 and 30. The recess 29 extends around a meridian of the hemi¬ spherical body, is arranged symmetrically on each side of the meridian and extends from adjacent the skirt 17 on one side of the body, for an arc of about 130°, to the other side of the body. The upper end of the recess 29, away from the skirt, has three spaced apertures 33 to enable powder in the container 11 to be dispensed from the container. A cavity 39 formed in the closure body 14 opens into the recess 29 and extends radially inwardly within the closure body. The cavity 39 has two radial sidewalls 37,38, which extend substantially parallel with the recess sidewalls 31,32, one wall 37 being substantially vertical in the normal upright position of the closure assembly and the other wall 38 making a bias angle to the vertical such that the cover 15 has the required freedom of movement within the cavity. The bias angle is suitably from between 30-40° and is preferably about 35°. With reference to Figures 3,4,5 and 6, the cover 15 comprises a part-spherical cover portion 41 having a part- spherical internal surface 42 co-operating with the external base surface 30 so that the cover 15 is slidable over the external part-spherical base surface 30 of the recess 29. A pair of spaced apart lugs 45 extend radially inwardly from the cover 15. Each lug 45 has a pivot pin 44 formed on its outer side which snaps into corresponding sockets (not shown) at the base of the cavity 39 where the sidewalls 37 and 38 intersect, so that the cover 15 can move in an arc about the pivot axis. The arc of movement is determined by the angle between the cavity sidewalls 37,38 and the positioning of the spring means 16. The radially outer portions of the two lugs 45 are interconnected by a web 46 to stiffen the lugs 45 and prevent the pivot pins 44 from springing out of their corresponding sockets. The spring means 16 is a leaf spring formed integrally with the cover portion 41 and located to one side of the web 46. As shown in Figure 4, the leaf spring 16 acts against the wall 38 of the cavity 39 to bias the cover to pivot in an anti-clockwise direction, as shown, so that a portion of the cover overlaps the apertures 33. The upper end shoulder 35 between the recess 29 and the larger diameter outer surface 27 acts as an abutment to limit movement of the cover under the bias of the spring 16. The external surface 47 of the cover portion 41 may have ribs 48 formed thereon (as shown) or be knurled to aid grip when moving the cover against the spring bias. The internal surface 42 of the cover portion 41 may have a raised base 51 thereon at its end portion adjacent the spring 16 which, in use, rubs against the outer surface 27 of the cover to act as a friction brake or damper. The outer end portion of the cover portion 41, away from the bias spring 16, has on its internal surface a projection defined by a raised rib 49 which in use will contact the base surface 30. The rib 49 forms an enclosure which encircles the apertures 33 to provide a seal. The closure assembly is shown in Figures 1 and 4 in its closed condition with the leaf spring 16 biasing the cover portion 41 against the upper shoulder 35 of the recess 29. In this condition the rib enclosure 49 surrounds the apertures 33. To open the closure assembly for dispensing powder from the container, the cover 15 is moved in the direction of arrow A (see Figures 1 and 4), relative to the closure body 14 from an aperture-closing first position to an aperture-revealing second position (as shown in Figure 2) . This can be done with one hand as may be necessary, for example, when performing certain tasks, e.g. when changing a nappy or diaper of a baby. On release, the spring means 16 automatically returns the cover to a position where the internal surface 42 of the cover portion 41 blocks off the apertures or holes 33. Figures 10 and 11 show a closure assembly similar to that previously described with reference to Figures 1 to 9 and, where appropriate, the same reference numbers are used hereinafter to identify similar components. The cover 15 is shown in cross-section in Figure 11. In order to prevent an initial opening of the closure assembly and/or to provide evidence of tampering, the closure assembly 13 is provided with a stop 52 which prevents the cover 15 from sliding in the recess from a first position to a second position in which the apertures 33 are uncovered. The stop 52 is integrally moulded with the cover 15 and is connected to the end of the cover 15, adjacent the spring 16, by frangible bridges 53. The stop 52 locates in the lower end of the recess 29 adjacent the skirt 17 so that the lower end of the stop 52 preferably abuts against the bottom shoulder 34 of the recess 29. Alternatively, the stop 52 could be arranged to abut against other portions of the hemi-spherical body 14 such as a shoulder 117 on the skirt 17. A tab 54 is connected to one side of the stop 52 through a flexible joint 55, preferably an integrally formed thinned hinge section, which allows the tab 54 to be oriented to project away from the surface of the body 14. This arrangement allows a user to grip the tab 54 and thereby to pull and detach the stop 52 from the cover 15 by rupturing the frangible bridges 53. Once the stop 52 has been removed the cover 15 can be opened as previously described. The removal of the stop 52 from the cover 15 serves as evidence that the closure assembly has been opened or tampered with. Furthermore, the necessity to remove the stop 52 to open the closure, may help make the closure childproof insofar as very young children are concerned.

Claims: CLAIMS 1. A self-closing closure assembly (13) for a container (11) of particulate material, comprising a closure body (14) for attachment to the mouth (12) of the container, the body (14) having a part-spherical external surface (30) in which at least one aperture (33) is provided for dispensing material from the container, a cover (15) mounted on the closure body (14) and having a part spherical inner surface (42) that is slidable over said part-spherical external surface (30) between an aperture-closing first position and an aperture-opening second position, and biasing means (16) formed integrally with one of the cover and body to act against the other of the cover and body to urge the cover towards said first position. 2. A closure assembly according to claim 1, wherein the cover (15) is pivotally mounted on the body (14). 3. A closure assembly according to claim 1 or 2, wherein the biasing means comprises a leaf spring (16) formed integrally with the cover and having a free end which reacts against the closure body (14) . 4. A closure assembly according to any one of claims 1 to 3, wherein said part-spherical external surface (30) comprises a recess (29) within a larger diameter part- spherical second surface (27) , said cover (15) being slidable within the recess and a first shoulder (34), between said spherical surfaces, acting as an abutment to limit movement of the cover at the second position. 5. A closure assembly according to claim 4, wherein pivotal movement of the cover (15) past its first position in the direction of the resilient biasing is limited by abutment of the cover against a second shoulder (35) of said recess (29) . 6. A closure assembly according to any one of the preceding claims, wherein the cover (15) has projecting means (49) engagable with the closure body (14) to seal said at least one aperture (33) when the cover is in its first position. 7. A closure assembly according to any one of the preceding claims, wherein said cover (15) has a boss (51) on its part-spherical inner surface which is frictionally engagable with said part-spherical external surface of the closure body (14) as the cover (15) slides over said body to form a friction damper. 8. A closure assembly according to claim 2 or any one of claims 3 to 7 when dependent on claim 2, wherein the cover (15) has a pair of spaced apart legs (45) each with a pivot pin (44) at its free end, the pins being a snap fit in apertures formed in a cavity (39) in the closure body. 9. A closure assembly according to claim 8 when dependent upon claim 3, wherein the leaf spring (16) is located on the cover (15) to one side of the pivot axis, is aligned midway between the two legs, and is housed in, and reacts against a wall (38) of, said cavity (39). 10. A closure assembly according to any one of the preceding claims, wherein said cover (15) is initially prevented from moving from the first position to said second position by a detachable stop (52) which serves as a tamper- evident device. 11. A closure assembly according to claim 10, wherein said stop (52) is secured to one end of the cover (15) by frangible connecting means (53). 12. A closure assembly according to claim 10 or claim 11, each when dependent upon claim 4, wherein the stop (52) is located within the recess (29) and abuts against said first shoulder (34). 13. A closure assembly as claimed in any one of claims 10 to 12, wherein the stop (52) is provided with a tab (54) connected to the stop through a flexible joint (55) and whereby the detachable stop may be removed from the closure assembly. 14. A container provided with a closure assembly according to any one of the preceding claims.

Inventors: MAYNE ANTHONY JOHN, MAYNE, ANTHONY, JOHN
Applicants: COURTAULDS PACKAGING LTD, MAYNE ANTHONY JOHN, COURTAULDS PACKAGING LIMITED, MAYNE, ANTHONY, JOHN
Application year: 1997
Main classification: B65D47
IPC codes: B65D47