Evacuable container having one-way valve with filter element

Abstract
A one-way valve allows air to be drawn from a collapsible, flexible, air-tight bag using a vacuum source. When the vacuum source is removed, the one-way valve prevents air from re-entering the bag. A filter is placed on the valve body to prevent small particles from the bag from clogging the valve or the vacuum source.
Description




FIELD OF THE INVENTION




The present invention relates to evacuable storage containers, and in particular to filters for one-way valves used in such storage containers.




BACKGROUND




Collapsible, evacuable storage containers typically include a flexible, air-tight bag, an opening through which to place an article in the bag, and a fixture through which to evacuate excess air. A user places an article into the bag through the opening, seals the opening, and then evacuates the air in the bag through the fixture. With the bag thus evacuated, the article contained therein may be significantly compressed so that it is easier to transport and requires substantially less storage space.




Collapsible, evacuable storage containers are beneficial for reasons in addition to those associated with compression of the stored article. For example, removal of the air from the storage container inhibits the growth of destructive organisms, such as moths, silverfish, and bacteria, which require oxygen to survive and propagate. Moreover, such containers, being impervious to moisture, inhibit the growth of mildew.




Not only large, compressible items such as clothing may be stored in a collapsible, evacuable storage container. For example, it may be desirable to store bulk items made of small particles, such as powders or granulated resins, in an evacuated container. One situation that commonly occurs is that a particular bulk item is shipped in a large, rigid container such as a drum. Bulk items may be moisture sensitive and are sealed against moisture during shipment. But many times a user does not need to use the entire contents of the large container, and so once exposed to air the remaining bulk contents quickly become unusable and are thus wasted.




One collapsible, reusable, evacuable storage container is shown in the above-referenced U.S. Pat. No. 5,480,030 issued to Sweeney et al., under common ownership with the present invention, and incorporated herein by reference in its entirety. The '030 patent discloses a one-way air valve assembly having a flexible diaphragm that seals against a valve seat. The valve assembly also has vanes positioned to prevent the bag material or bag contents from obstructing air holes or the diaphragm while air is being evacuated through the valve assembly. These vanes may protect against the bag material, or against large objects stored in the bag, but the vanes do not prevent small particles from entering the air holes and either blocking air holes or preventing the diaphragm from properly closing once evacuation is complete. Furthermore, small particles may be carried through the valve and become lodged in the vacuum producing device used to evacuate the storage container, thus affecting operation of the vacuum producing device.




Therefore the need exists for a reusable, collapsible, evacuable storage container that may store bulk items that include particles or granules.




SUMMARY




Embodiments of the invention are directed to collapsible, evacuable storage containers. These storage containers have a one-way valve assembly allowing air to pass out of a flexible, air-tight bag, but not to return to the bag through the valve assembly. A filter is configured to be fitted against the one-way valve assembly so that material in the bag does not pass into or through the valve assembly when air is evacuated from the bag.




In one embodiment of the invention, the filter is made to be compatible with an existing one-way valve assembly. A filter assembly is formed of a cylinder capped by a top portion. The top portion has air slots through which air passes before entering the one-way valve assembly. A filter element is placed in the filter assembly so that air passing through the air slots is filtered. Embodiments of the invention may include filter elements providing filtration for various particulate sizes.




In an embodiment of the invention, the cylinder of the filter assembly contains a plurality of slots so that the filter assembly may be placed over radial vanes on the valve body. These slots are formed so that when the filter assembly is pressed onto the valve assembly, a seal is formed between the filter assembly and the vanes. In one embodiment of the invention, an annular lip is positioned at the base of the cylinder. This lip is configured to seal the filter assembly against a corresponding inner wall of the valve assembly.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of an embodiment of the invention.





FIG. 2

is a perspective view of a flexible bag.





FIG. 3

is an exploded perspective view showing an embodiment of a valve assembly and of a filter assembly.





FIG. 4

is a plan view showing an embodiment of a filter assembly in position on a valve assembly.





FIG. 5

is a cross-sectional view showing an embodiment of a filter assembly mated with a valve assembly.





FIG. 6

is a perspective view showing another embodiment of the invention.











DETAILED DESCRIPTION




In the drawings that accompany this description, the same numbered elements shown in separate figures are intended to represent similar elements. The embodiment of the filter assembly shown in the accompanying drawings is intended to be fitted against an existing one-way valve in an existing collapsible, evacuable container. This container is known as a SPACE BAG, and is manufactured by NEW WEST PRODUCTS, INC. of Redwood City, Calif. Those skilled in the art will appreciate that embodiments of the filter assembly may be adapted for use with a wide variety of one-way valves and containers.





FIG. 1

is a perspective view of an embodiment of the invention. An evacuable container


2


includes a bag


4


, a valve assembly


6


, and a seal


8


. During use, one or more discrete articles or a bulk material may be placed in bag


4


, after which bag


4


is sealed using seal


8


. Air is drawn out of bag


4


through valve assembly


6


using a conventional vacuum source, such as a household or industrial vacuum cleaner. Valve assembly


6


and seal


8


maintain the vacuum inside bag


4


when the vacuum source is removed. Details regarding embodiments of valve assembly


6


are discussed in U.S. Pat. No. 5,480,030, mentioned above, and also in application Ser. No. 08/851,361 incorporated herein by reference in its entirety. Additional embodiments of valve assembly


6


are discussed below and shown in the accompanying drawings. In one embodiment, seal


8


is an interlocking air tight Zipper-type fastener manufactured by Minigrip/Zip-Pak (An ITW Company) of Mission Viejo, Calif.





FIG. 2

illustrates an embodiment of bag


4


. Bag


4


has a hole


10


in which to install valve assembly


6


, and an opening


12


through which articles or bulk material may be placed for storage. Details regarding embodiments of bag


4


are discussed in U.S. Pat. No. 5,480,030, mentioned above. In one embodiment the bag is constructed of a blended extrusion layer of polyethylene sandwiched between a nylon layer and a layer of polyethylene sheeting. In some embodiments materials comprising the bag may be altered so as to prevent interaction with the bag contents. Such a custom bag composition is based on user need and may be determined using material qualities known in the art or by experimentation.





FIG. 3

is an exploded perspective view showing valve assembly


6


and filter assembly


14


. As shown, valve assembly


6


is comprised of a base


16


, a retaining ring


18


, and a valve element


20


. Valve assembly


6


is mounted to bag


4


(

FIGS. 1 and 2

) such that flange


17


of base


16


is on the inside of bag


4


. Base


16


extends through hole


10


and is held in place by retaining ring


18


placed over base


16


on the outside of bag


4


.




Valve element


20


provides the one-way feature in valve assembly


6


. In the embodiment shown, valve element


20


is made of conventional clear polyvinylchloride (PVC). Valve element


20


has an outer annular portion


22


and an inner diaphragm


24


. Annular portion


22


functions as a face against which a vacuum source, such as a conventional household or industrial vacuum cleaner nozzle (FIG.


6


), may be sealed as the nozzle is pressed against base


16


. When the nozzle is in place and a vacuum pressure draws air through the nozzle, diaphragm


24


flexes open and air passes through a plurality of holes


26


in base


16


. When the nozzle is removed, diaphragm


24


returns to its original shape and seals against base


16


, thus preventing air from passing back through holes


26


.




As shown, a plurality of radial vanes


28


separate holes


26


. Vanes


28


hold a central valve element support


29


. Thus each of holes


26


is formed as the open space bounded by recessed portion


16


B of base


16


, two each of vanes


28


, and valve element support


29


.

FIG. 5

provides another view of holes


26


. As shown, vanes


28


, spaced around support


29


, are separated by holes


26


.




Referring again to

FIG. 3

, filter assembly


14


fits against valve assembly


6


. Filter assembly


14


is comprised of a top portion


30


and a cylindrical sidewall


32


. Other embodiments may have different sidewall shapes, the sidewall being adapted for use with a particular valve base. As shown, filter assembly


14


fits against base


16


to form a seal tight enough to keep any material stored in bag


4


from passing into valve assembly


6


. In some embodiments this seal may be air-tight. A plurality of slots


34


in filter sidewall


32


are configured to fit over respective vanes


28


in base


16


. A raised annular lip


36


fits against base


16


's inner wall


38


. Details of the fit between filter assembly


14


and base


16


are discussed in detail below.




Filter assembly


14


has a plurality of openings


40


through which air passes while being drawn through valve assembly


6


. As shown, openings


40


are arranged in a series of fan-shaped patterns having curved slots. Other embodiments of filter assembly


14


may use different shapes and patterns for openings


40


. A filter element


42


, visible for example through one of the openings


40


, is placed underneath top portion


30


and underlies openings


40


to prevent stored material from entering valve assembly


6


.




In one embodiment, filter assembly


14


is made of conventional polyethylene. In another embodiment, filter assembly


14


may be made of acrylonitrile-butadiene-styrene (ABS), known by trade names such as CYCOLAC or LUSTRAN. Some embodiments of the filter are injection molded. Other embodiments may be made using conventional fabrication methods such as milling. The material forming filter assembly


14


is soft, so that a slight deformation occurs as filter assembly


14


is pressed against base


16


, as described below. The deformation provides both a seal and friction by which filter assembly


14


stays in place.




In one embodiment of the invention, filter element


42


is a 47 millimeter diameter, 0.02 micrometer PTFE membrane filter, supplied by Paul Gilman Laboratories of Fremont, Calif., as part S-66143, TF-200. The 47 mm filter element is then cut to slightly less than 1.34 inches so as to fit within filter assembly


14


. Embodiments of this invention are not restricted to using this filter element type only, however, and other embodiments may use other filter element types. For example, filter element


42


may be optimized for a certain type of material to be stored within an evacuable container. User requirements may dictate filter element


42


composition. Filter element


42


may be attached to filter assembly


14


using various methods. For example, in one embodiment, filter element


42


is attached to filter assembly


14


using direct heat transfer. In other embodiments, sonic welding or other adhesive or connecting methods may be used. Filter assembly


14


may be permanently attached to base


16


, or filter assembly


14


may detachable from base


16


in order to, for example, permit filter element


42


to be replaced.




As mentioned above, slots


34


are configured to fit over vanes


28


. In some embodiments in which vanes are not used, however, slots


34


may be omitted. In one embodiment, each slot


34


is 0.060±0.002 inch wide and 0.47 inch long to ensure an adequate seal when filter assembly


14


is pressed onto base


16


.




In the embodiment shown, a raised annular lip


36


is positioned around the base of sidewall


32


. This lip


36


adds extra tension to the junction of, and improves the seal between, sidewall


32


and base


16


. Annular lip


34


provides an improved seal between filter assembly


14


and base


16


over a seal between a straight edge junction of sidewall


32


and base


16


.





FIG. 4

is a plan view showing an embodiment of filter assembly


14


mounted on an embodiment of base


16


. As depicted, filter assembly


14


fits over a plurality of radial vanes


28


(partially hidden by filter assembly


14


) positioned on base


16


.





FIG. 5

is a cross-sectional view showing an embodiment of valve assembly


6


mated with filter assembly


14


, taken at cut line A—A in FIG.


4


. Valve base


16


is shown inserted through a flexible, air-tight bag


4


and held in place by an annular retaining ring


18


. An opening


50


is provided in base


16


in which a nozzle (

FIG. 6

) from a vacuum source is placed to draw air through the valve. In some embodiments, a removable cap (not shown) may be placed over opening


50


to protect inner portions of valve assembly


6


. A plurality of vanes


28


are positioned on the underside of base


16


.




Flexible diaphragm


24


is shown in position against a seat


52


. As described above, when a vacuum source nozzle is placed into opening


50


, vacuum pressure causes diaphragm


24


to flex and allow air, represented by arrow


54


, to be drawn through valve assembly


6


. When the vacuum source nozzle is removed, diaphragm


24


returns to its position sealed against seat


52


so as to prevent air from flowing in a reverse direction through the valve. In the embodiment shown, diaphragm


24


and annular portion


22


are an integral piece, joined by two small bridge pieces (FIG.


3


).




As mentioned above, further details regarding evacuable containers and one-way valves are given in U.S. Pat. No. 5,480,030, and in application Ser. No. 08/851,361.




Still referring to

FIG. 5

, filter assembly


14


is shown mated with valve base


16


. Lip


36


is shown sealing sidewall


32


against valve base inner surface


38


. As shown, filter assembly


14


's sidewall bottom surface


37


is shown sealed against base


16


's surface


56


, although in other embodiments a slight gap is allowable due to the seal between lip


36


and surface


38


.




Also shown is a vane


28


A extending through a slot


34


in filter assembly


14


. It may be seen that the length of slot


34


should not exceed the height of a vane


28


, or else leakage may occur near the top junction


58


.




Filter element


42


is shown attached to the underside of filter assembly


14


's top portion


30


. Filter element


42


is positioned so that air, represented by arrow


54


, is filtered as it passes through each of the several air holes


40


.





FIG. 6

is a perspective view showing an embodiment of the invention during use. A container


70


is shown having a bag


4


placed in a rigid vessel


71


to allow easier handling of a stored bulk material such as a powder or granules. The rigid vessel should be strong enough to hold the desired bulk contents during routine handling. In some embodiments the rigid container may be a conventional container made of plastic, corrugated fiber, bonded fiber, wood, or metal. In other embodiments the container may be custom-fabricated to meet user needs. In some embodiments, the rigid vessel


71


may be omitted.




Stored material may be placed in bag


4


so as to fill vessel


71


. As shown, however, a portion of stored bulk material has been removed from bag


4


, illustrating the reusable nature of the evacuable container


70


. Bag


4


has been sealed with seal


8


. A nozzle


72


from a vacuum source


74


is placed, by hand for example, against valve assembly


6


. As described above, vacuum source


74


draws air out from bag


4


through valve assembly


6


. When sufficient air has been withdrawn from bag


4


, nozzle


72


is removed and both valve assembly


6


and seal


8


prevent air from reentering bag


4


. If at a later time an additional portion of material stored in bag


4


is to be taken, seal


8


is opened, the material is removed from bag


4


, and then bag


4


is resealed and reevacuated as described.




An advantage of embodiments of this invention is that it provides a reusable, evacuable container for granular or powdered bulk material. Such bulk materials may include items such as nylon resins, tea, cork, and foam products. Embodiments of the filter assembly prevent the bulk material from entering and clogging both valve assembly


6


and the vacuum source used to evacuate bag


4


.




Another advantage of the embodiment shown and described is that filter assembly


14


may be removed and replaced with a fresh assembly if the filter element


42


becomes clogged. As shown in

FIG. 6

, a user opens seal


8


and reaches into bag


4


to remove and replace filter assembly


14


. In other embodiments, however, filter assembly


14


may be permanently attached to, or formed as an integral part with, valve assembly


6


.



Claims
  • 1. A method of manufacturing a storage container, comprising the acts of:providing a flexible, air-tight bag having an opening for inserting material to be stored; providing an air-tight seal across the opening; providing a one-way valve assembly installed in the bag, wherein the valve assembly comprises a plurality of vanes and allows air to pass out of the bag but prevents air from entering the bag; and providing a filter assembly shaped to mate with the valve assembly, to fit over the vanes, and to form a seal with the vanes, wherein the filter assembly comprises at least one hole formed therein, and wherein the filter assembly supports a filter element across the or each hole such that air passing out of the bag through the valve assembly is filtered.
  • 2. The method of claim 1, wherein the air-tight seal is resealable.
  • 3. The method of claim 1, wherein the filter assembly is held against the valve assembly by friction.
  • 4. The method of claim 1, wherein the filter assembly is made to be removable from the valve assembly so that a second filter assembly may be mated with the valve assembly.
  • 5. The method of claim 1, wherein the filter assembly comprises:a cylindrical side wall having an outside surface and a first end; a top portion positioned as a cap over the side wall at the first end; and a raised annular lip positioned on the outside surface at an end opposite the first end, wherein the annular lip is configured to seal against a surface of the valve assembly.
  • 6. The method of claim 1 comprising the act of providing the valve assembly and the filter assembly as an integral piece.
  • 7. The method of claim 1 comprising the act of providing the filter element to prevent particles of a material stored in the bag from entering the valve assembly.
  • 8. The method of claim 1, wherein the filter element comprises an about 0.02 micrometer filter.
  • 9. The method of claim 1 comprising the act of providing a rigid vessel into which vessel the bag is placed.
  • 10. The method of claim 1, wherein the one-way valve assembly is configured to receive a nozzle coupled to a vacuum source.
  • 11. A method of manufacturing a storage container, comprising the acts of:providing a flexible, air-tight bag having an opening for inserting material to be stored; providing an air-tight seal across the opening; providing means for allowing air to pass out of the bag but not to pass into the bag, wherein the means for allowing air to pass out of the bag but not to pass into the bag comprises a plurality of vanes; and providing means for filtering air passing out of the bag, wherein the means for filtering air passing out of the bag comprises at least one hole formed therein, wherein the means for filtering air passing out of the bag supports means for filtering air passing through the or each hole, and wherein the means for filtering air passing out of the bag comprises a plurality of slots shaped to receive the vanes.
  • 12. The method of claim 11, wherein the seal is resealable.
  • 13. The method of claim 11, wherein the means for filtering air passing through the or each hole is held by friction against the means for allowing air to pass out of the bag but not to pass into the bag.
  • 14. The method of claim 11, wherein the means for filtering air passing out of the bag is made to be removable from the means for allowing air to pass out of the bag but not into the bag.
  • 15. The method of claim 11, wherein the means for filtering air passing out of the bag prevents particles of a material stored in the bag from entering the means for allowing air to pass out of the bag but not to pass into the bag.
  • 16. The method of claim 11 furtherer comprising the act of providing means for rigidly supporting the bag.
  • 17. The method of claim 11, wherein the means for allowing air to pass out of the bag but not to pass into the bag is configured to receive means for coupling to a vacuum source.
RELATED APPLICATIONS

This application is a divisional of application Ser. No. 09/310,468, filed May 12, 1999 now U.S. Pat. No. 6,408,872, and incorporated hereinby reference, which is a continuation-in-part of application Ser. No. 08/851,361, filed May 5, 1997, now issued as U.S. Pat. No. 5,931,189, which is a continuation of application Ser. No. 08/423,761, filed Apr. 17, 1995, now abandoned which is a divisional of application Ser. No. 08/168,963 filed Dec. 15, 1993, now issued as U.S. Pat. No. 5,480,030.

US Referenced Citations (40)
Number Name Date Kind
2821338 Metzger Jan 1958 A
2913030 Fisher Nov 1959 A
3060985 Vance et al. Oct 1962 A
3135411 Osborne Jun 1964 A
3141221 Faulls, Jr. Jul 1964 A
3313444 Katell Apr 1967 A
3351270 Hohnjec Nov 1967 A
3403696 Pynchon Oct 1968 A
3454182 Morton Jul 1969 A
3574306 Alden Apr 1971 A
3831628 Kintner et al. Aug 1974 A
3911949 Hilden et al. Oct 1975 A
3958693 Greene May 1976 A
4082201 Bittel Apr 1978 A
4209485 Greenspan Jun 1980 A
4212337 Kamp Jul 1980 A
4372921 Sanderson et al. Feb 1983 A
4486923 Briggs Dec 1984 A
4712574 Perrott Dec 1987 A
4747702 Scheibner May 1988 A
4778282 Borchardt et al. Oct 1988 A
4786285 Jambor Nov 1988 A
4812056 Zieke Mar 1989 A
4871264 Robbins et al. Oct 1989 A
4892414 Ausnit Jan 1990 A
4917506 Schiebner Apr 1990 A
5063639 Boeckmann et al. Nov 1991 A
5067822 Wirth et al. Nov 1991 A
5080155 Crozier Jan 1992 A
5111938 Soprano et al. May 1992 A
5121590 Scanlon Jun 1992 A
5142970 ErkenBrack Sep 1992 A
5203458 Cornwell Apr 1993 A
5242516 Custer et al. Sep 1993 A
5282322 Kasuya Feb 1994 A
5368394 Scott et al. Nov 1994 A
5371925 Sawatsky Dec 1994 A
5397182 Gaible et al. Mar 1995 A
6070728 Overby et al. Jun 2000 A
6408872 Skeens et al. Jun 2002 B1
Foreign Referenced Citations (7)
Number Date Country
3917344 Nov 1990 DE
0342317 Nov 1989 EP
0153044 Nov 1999 EP
4-36940 Jun 1992 JP
4-189752 Jul 1992 JP
404189752 Jul 1992 JP
4-242544 Aug 1992 JP
Non-Patent Literature Citations (1)
Entry
Copy of Packaging of Vacuum Shrink Depositing Bags for Cotton Products from Beijing J2 Jia Li New Technology Developing Co.
Continuations (1)
Number Date Country
Parent 08/423761 Apr 1995 US
Child 08/851361 US
Continuation in Parts (1)
Number Date Country
Parent 08/851361 May 1997 US
Child 09/310468 US