CLOSURE FOR CREATING A VACUUM CONTAINER

Abstract: A cap device (10) for creating a partial vacuum in a container comprising a pump formed from an inner attachment member (12) for releasably securing to an opening of the container, and an outer user engagement member (14) slidably and non-rotatably mounted on the inner attachment member to provide the pump cylinder and a one-way (22) valve connecting the pump cylinder to the interior of the container (16). The valve is configured to permit air to be removed from the container by a reciprocating sliding action of the outer member relative to the inner member such that a partial vacuum is created and maintained.

Description: CLOSURE FOR CREATING A VACUUM CONTAINER The present invention relates to a cap device for use for evacuating air from a container to create a partial vacuum. Many foodstuffs such as coffee, for example, retain their flavour and/or aroma for longer periods if stored in a container in partial vacuum conditions. Such foodstuffs are generally supplied to the consumer in a sealed jar or similar container, however, once the seal has been broken, a screw cap is generally used to re-close the container and provide a substantially airtight seal when the foodstuff is stored. The air within the container is, however, maintained at atmospheric pressure, potentially leading to the degradation of the foodstuff over time. The present invention seeks to overcome, or at least mitigate the problems of the prior art. A first aspect of the invention provides a cap for creating a partial vacuum in a container comprising a pump formed from an inner attachment member for releasably securing to an opening of the container, and an outer user engagement member slidably and non- rotatably mounted on the inner attachment member to provide the pump cylinder and a one-way valve connecting the pump cylinder to the interior of the container which valve configured to permit air to be removed from the container by a reciprocating sliding action of the outer member relative to the inner member such that a partial vacuum is created and maintained. A second aspect of the invention provides a cap device for creating a partial vacuum in a container comprising an attachment member for releasably securing to an opening of the container, and an engagement member reciprocally mounted with respect to the attachment member and a valve configured to permit fluid to be removed from the container during reciprocating sliding action of one member relative to the other member such that a partial vacuum is created and maintained. An advantage of either aspect of the invention is that the reduction in pressure w ithin the container leads to reduced degradation of the foodstuff. According to an optional feature of the second aspect of the invention the attachment and engagement members may be co-axial and the engagement member may be shaped to fit over the attachment member to facilitate the reciprocal sliding action of the engagement member. According to another optional feature of the second aspect of the invention the attachment and engagement members ma\ define a pump chamber, the volume of the pump chamber niay vary in response to the relative positions of the attachment and engagement members. Optionally, the λ'alve is a one-way valve provided on the attachment member to enable air to be drawn from the container into the pump chamber. According to another optional feature of this aspect of the invention a further one-way valve may be provided on the engagement member to cause air in the pump chamber to be removed as the volume decreases. Preferably, the engagement member valve is provided by a seal between the free edge of the engagement member, and the attachment member. Optionally, the engagement member may comprise an upper portion and a cylindrical lower portion formed integrally therewith and the seal is provided by an integral extension of the lower portion. According to a further optional feature of the second aspect of the invention there ma)' further comprises a plurality of recesses provided on the inner surface of the engagement member to aid fluid flow between the adjacent surfaces of the attachment and engagement members. According to yet another optional feature of the second aspect of the invention the device may be provided with a lug on one of the members and may be slidable in a co-operating slot provided on the other of the members so as to permit non-rotatable slidable movement of the one member relative the other of the members. Preferably, there may comprise three lugs in spaced axial alignment adapted to stabilise the engagement member. Optionally, the attachment member is attached to the container using a screw fitting. Exemplary embodiments of the present invention are described, by way of example only, with reference to the accompanying drawings in which: FIGURE 1 is an exploded perspective view of a cap device according to a first embodiment of the invention; FIGURE 2 is a plan view cross section through the assembled cap of Figure 1 ; FIGURE 3 is a cross section through the cap along the line X-X of Figure 2; FIGURES 4A and 4B are a plan view and sectional view through A-A of the outer engagement member of a second embodiment; and FIGURES 5 A and 5B are a plan view and a sectional view through B-B of the inner engagement member of a second embodiment; and FIGURE 6 is a side elevation and partial cross-section of the cap device according to a second embodiment. Referring to the drawings and, in particular Figure 1. there is shown a cap device 10 for use in creating a partial vacuum in a container such as ajar 16. The cap device is made from suitable plastics, rubber or metal materials. In alternative classes of embodiment. the device may be used to evacuate other containers such as bottles, for example. The cap device 10 comprises a first member which is, in use, releasably secured to an opening of the container and a second member to be secured to the first member. In this embodiment. the first and second members are referred to as attachment and engagement members 12 and 14. In the embodiment illustrated in Figure 1 , the engagement member 14 is slidably and non-rotatably mounted on the attachment member 12 and configured to permit fluid, for example air. to be removed from the container by a reciprocating sliding action of the outer member 14 relative to the attachment member 12. Attachment member 12 preferably comprises a substantially circular planar upper portion 30 and a cylindrical lower portion 28 which may be formed integrally therewith. In this embodiment, the inner face of cylindrical portion 28 is provided with screw threads 36. shown in Figure 3. which co-operate with a corresponding threads 26 on the jar 16 to releasably secure the device thereto. It is envisaged that in alternative embodiments, other securing means such as clips which fit over a lip on a container may be used. Referring to Figure 3. a one way valve 22 is provided on the attachment member. In this embodiment, it is advantageously provided on the upper portion 30 of the inner member 12 for reasons described below. However it is envisaged that the valve could be provided along the cylindrical portion, without departing from the scope of invention. An annular seal 38 is preferably provided on the inner face of upper portion, such that once a partial vacuum has been created in the jar 16. it may be maintained. In other classes of embodiment the annular seal 38 may be dispensed with if a sufficient vacuum can be maintained without it being provided. Engagement member 14 similarly comprises a substantially planar circular upper portion 34, and cylindrical lower portion 32. again preferably formed integrally therewith, the dimensions of the outer member 14 being slightly larger than the attachment member 12 such that the engagement member 14 may fit snugly over the attachment member 12. The outer face of the lower portion 32 may advantageously be textured or shaped to enhance frictional engagement with a user ' s hand. Guide means, such as lugs 18 are further provided on cylindrical portion 28 to non- rotatably and slidably attach outer member 14 to inner member 12. The lugs 1 8 further act as stops to prevent the outer member 14 becoming separated from the inner member on an upstroke of the outer member 14. Alternatively, other guide means such as a linear cam and cam follower can be employed. In this embodiment, the attachment member is shown having four lugs 18. as can be seen most clearly in Figure 2. However, in alternative embodiments, the device may function with one lug. although two or more are preferable. More preferably, there should be at least three lugs to act as the upstroke stops so as to improve stability of the engagement member. Specifically, the position of the lugs in this embodiment reduce the possibility of the outer engagement member 14 becoming separated or oriented at an angle with respect to the inner member 12 thereby causing the members to jam making it difficult to move one member relative the other. In other embodiments it is envisaged that the outer surface of the attachment member and the corresponding inner face of the engagement member 14 could be multi-faceted, for example a square shape, the shape act as a guide thereby making lugs unecessan . Turning again to the first embodiment, slots 20 are preferably provided on the inner face of the lower portion 32. and are configured to co-operate with lugs 18 such that when fitted together, the outer member 14 may slide axially relative to inner member 12. but no relative rotation may occur therebetween. In other embodiments, the lugs and corresponding slots can be interchanged and provided on the cylindrical portions 32 and 28 respectively. Sealing means 24 is preferably provided around the circumference of the lower margin of lower portion 32. and is adapted to provide a seal between the inner face of lower portion 32, and the outer face of lower portion 28. To this end it is preferable that lower portion 28 is substantially smooth such that a seal may be maintained. The seal can be manufactured from suitable plastics or rubber material. It is envisaged that the sealing means could be integral with the engagement member and/or manufactured from similar materials. For example, the engagement member 14 could be manufactured to include a seal provided by a protrusion from the free edge of the lower portion 28 which is stressed to allow it to flex. To allow the fluid to pass between the lower portions 28. 32 of the attachment and engagement members 12 and 14. the inner face of the engagement member is preferably provided with a plurality of vertical channels 40 shown in Figure 1 extending from the top to the bottom thereof. The second embodiment of the invention is illustrated in Figures 4A. 4B. is a 5Band 6 and is similar to the embodiment described above with the same reference numerals being used, but prefixed with the numeral "1 ". Only the changes with respect to the first embodiment are discussed in greater detail below. In this embodiment, larger channels 140 are provided in outer member 14 to improve fluid flow between the cylindrical portions of the inner and outer members 12. 14. Additionally, in this embodiment the one-way valve 122 comprises an aperture 122 in the planar portion 130 of inner member 1 12, and a resilient flap 125 secured to planar portion 130 by push fit plug member 123. To construct the cap device 10. the outer engagement member 14 is sized to enable a "snap fit' " to occur whereby the cylindrical portion 32 is forced outwards over the lugs 18 until they are engaged with the respective slots 20, to return to their original position. To aid construction, the lugs 18 may be champfered or rounded. The cap device 10 is applied to the container in the conventional manner and locking means can be employed to retain the device in place during transit and initial sale. For example, the cap device 10 and optionally the container could be covered in a plastics film which is detachable upon opening the cap. Alternatively, the outer member 14 may be frangibly connected to a ring to be separated therefrom when first separating the cap device from the container. In order to use the cap device 10, reference is made to Figure 3. The user engages the outer member 14 to screw the device 10 on to jar 16, preferably such that it is seated against seal 38. The seal is preferably connected to the inner face of attachment member, as shown in Figure 3. although in other embodiments it can be formed along the lower edge of this member to abut a radially protruding portion or shoulder portion of the container. In order to evacuate the jar. outer member 14 is first pulled upwardly in direction X referred to as the upstroke with respect to inner member 12 such that air is drawn from the container 16 into the void 42 formed between the inner and outer members 12 and 14. As the air cannot return through valve 22. when outer member 14 is pushed downwardly or downstroke in a direction Y the air is expelled via channels 40 and past seal 24 which are configured to effectively act as a one way valve. Alternatively a further one way valve (not shown) may be fitted to the outer member 14 and a connecting seal used. This pumping action may be repeated until the user is satisfied that the container 16 has been sufficiently evacuated. A safety valve (not shown) of known type may be fitted to the device to ensure that the vacuum created is not too g reat - To remove the device 10 if access to the contents of the jar 16 is required, the device may simply be unscrewed. To minimise the force required to complete the unscrewing motion, a pressure relief valve (not shown) may be fitted to the cap such that air may be re-introduced into the container before the cap 10 is unscrewed. In order to enhance the aroma emitted from the container, thereby enhancing the desirability of the contents of the container to a consumer thereof, an aroma emitting device (not shown) may advantageously be fitted to the cap. In one embodiment the aroma emitting device may be intergrated with valve 22, 122 such that the aroma is transferred into the fluid passing through the valve. In alternative embodiments, the aroma device may be secured to the inner face of outer member 14, or the outer face of inner member 12 such that the aromas is transferred to fluid passing through the void 42. It is envisaged that the cap device may be sold to the consumer together with the foodstuffs and container or be sold separately in sizes to fit standard containers and supplied on a retro-fit basis. Numerous changes may be made within the scope of the present invention, for example, the cap may be adapted to fit containers of different types.

Claims: CLAIMS 1. A cap for creating a partial vacuum in a container comprising a pump formed from an inner attachment member for releasably securing to an opening of the container, and an outer user engagement member slidably and non-rotatably mounted on the inner attachment member to provide the pump cylinder and a one-way valve connecting the pump cylinder to the interior of the container which valve configured to permit air to be removed from the container by a reciprocating sliding action of the outer member relative to the inner member such that a partial vacuum is created. 2. A cap device for creating a partial vacuum in a container comprising an attachment member for releasably securing to an opening of the container, and an engagement member reciprocally mounted with respect to the attachment member and a valve configured to permit fluid to be removed from the container during reciprocating sliding action of one member relative to the other member such that a partial vacuum is created. 3. The device as claimed in claim 2 wherein the attachment and engagement members are co-axial and the engagement member is shaped to fit over the attachment member to facilitate the reciprocal sliding action of the engagement member. 4. The device as claimed in claim 2 or claim 3 wherein the attachment and engagement members define a pump chamber, the volume of the pump chamber varying in response to the relative positions of the attachment and engagement members. 5. The device as claimed in claim 4 wherein the valve is a one-way valve provided on the attachment member to enable air to be drawn from the container into the pump chamber. 6. The device as claimed in claim 5 wherein a further one-way valve is provided on the engagement member to cause air in the pump chamber to be removed as the volume decreases. 7. The device as claimed in claim 6 wherein the engagement member valve is provided by a seal between the free edge of the engagement member, and the attachment member. 8. The device as claimed in claim 7 wherein the engagement member comprises an upper portion and a cylindrical lower portion formed integrally therewith and the seal is provided by an integral extension of the lower portion. 9. The device as claimed in claim 8 wherein there further comprises a plurality of recesses provided on the inner surface of the engagement member to aid fluid flow- between the adjacent surfaces of the attachment and engagement members. 10. The device as claimed in any preceding claim wherein a lug is provided on one of the members and is slidable in a co-operating slot provided on the other of the members so as to permit non-rotatable slidable movement of said one member relative said other of the members. 1 1. The device as claimed in claim 10 wherein there comprises three lugs in spaced axial alignment adapted to stabilise the engagement member. 12. The device as claimed in any preceding claim wherein the attachment member is attached to the container using a screw fitting. 13. The device as claimed in any preceding claim which is re-usable. 14. A cap device as claimed in any of claims 1 to 13 and a container with an opening so constructed and arranged to be releasably secured to the cap device. 15. The use of a device according to any one of claims 1 to 13 to partially evacuate a container.

Inventors: BLANDFORD MICHAEL BRIAN, EVERITT JULIAN DONALD, NUNN PETER RICHARD, BLANDFORD, MICHAEL, BRIAN, EVERITT, JULIAN, DONALD, NUNN, PETER, RICHARD
Applicants: BLANDFORD MICHAEL BRIAN, EVERITT JULIAN DONALD, NUNN PETER RICHARD, BLANDFORD, MICHAEL, BRIAN, EVERITT, JULIAN, DONALD, NUNN, PETER, RICHARD
Application year: 2000
Main classification: B65D81
IPC codes: B65D81