DEVICE AND METHOD FOR EVACUATING A
BACKGROUND OF THE INVENTION
Storage bags are commonly used for a variety of purposes such as storing food items. Such storage bags are typically made from a flexible, thermoplastic web material that is configured to provide an interior volume into which food items can be inserted. To preserve the inserted food, the storage bag l o may also include a closing mechanism, such as interlocking fastening strips, for sealing closed an opening through which the interior volume is accessible.
One problem that occurs with the aforementioned storage bags is that latent air may remain trapped within the interior 15 volume after sealing closed the opening. The trapped air may cause spoiling or dehydration of the food items. To remove the trapped air, a one-way valve element may communicate with the interior volume. The one-way valve element allows for the evacuation of trapped air while preventing the ingress 20 of air from the surrounding atmosphere into the interior volume. Methods of conveying the entrapped air through the one-way valve element include squeezing the flexible sidewalls to force air through the valve element or utilizing a mechanical evacuation device that can interface with the one- 25 way valve element.
Where an evacuation device is used, the evacuation device typically operates by creating a pressure differential across the one-way valve element causing the valve element to open. Entrapped air can then be drawn from the interior volume 30 through the one-way valve element by the evacuation device and exhausted to the surrounding atmosphere. Once the evacuation device is removed, the pressure differential between the surrounding atmosphere, typically at 14.7 pounds per square inch (PSI), and the interior volume closes 35 the valve element. One problem is that the pressure differential used to open and draw air through the valve element may damage the storage bag. Another problem is that evacuating air from the interior volume may cause the flexible sidewalls to collapse in a manner that can damage the stored items. 40
BRIEF SUMMARY OF THE INVENTION
The invention provides a system and method for evacuating air from the interior volume of a flexible storage bag via a 45 one-way valve element. The invention includes a handheld evacuation device having a housing to be gripped by a user and further having a nozzle providing an inlet opening to be positioned over the one-way valve element on the storage bag. Enclosed within the housing is an airflow generating unit 50 for drawing air through the inlet opening. The maximum evacuation pressure generated by the airflow generating unit may be about 6 pounds per square inch absolute (PSIA) or greater. By way of reference, absolute pressure refers to the total measurable pressure from zero PSI, with atmospheric 55 pressure at sea level typically being about 14.7 PSI. In various aspects, to assure that the maximum evacuation pressure is about 6 PSIA or greater, the evacuation device may also include a pressure control feature which may be pressure activated or user selectable. 60
The invention also provides a method of storing food items in a manner that preserves their freshness and appearance. The method includes a flexible storage bag that provides an interior volume and a one-way valve element communicating with the interior volume. The food items are inserted into the 65 interior volume and the opening of the storage bag is sealed closed. A handheld evacuation device is positioned over the
one-way valve element. When activated, the evacuation device may exert a maximum evacuation pressure of about 6 PSIA or greater and draws air entrapped in the interior volume through the valve element.
An advantage of the invention is that, by exerting a maximum evacuation pressure of about 6 PSIA or greater, potential damage to the storage bag can be prevented. Another advantage is that evacuation pressure resulting inside the interior volume is approximately 6 PSIA or greater. At this evacuation pressure, it is believed that many foods items can be adequately preserved while at the same time the flexible sidewalls will not be so tightly drawn about the food items so as to damage them or distort their appearance. A further advantage is that evacuating food items to only 6 PSIA or greater avoids or reduces dehydration or the removal of fluids and juices from food items that may occur when evacuating food items to lower pressures. Yet another advantage is that a system that evacuates to about 6 PSIA or greater can be made with less complexity and precision than is required for a system that evacuates foods to a lower pressure. These and other advantages and features of the invention will become apparent from the detailed description and the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL
VIEWS OF THE DRAWINGS
FIG. 1 is a perspective view of the components that may be included in an evacuable storage system including a storage bag having a one-way valve element and a handheld evacuation device configured to operate with an electric motor.
FIG. 2 is a cut-away view showing another embodiment of the handheld evacuation device having a pressure control feature and configured to operate similar to a hand pump.
FIG. 3 is side elevational view of another embodiment of a hand held evacuation device having a user selectable pressure control feature including a rotating ring and alignable holes.
FIG. 4 is a side elevational view of the hand held evacuation device of FIG. 3 showing the pressure control feature in a different position.
FIG. 5 is a perspective view of another embodiment of a hand held vacuum device having a user selectable pressure control feature including a slide and alignable holes.
FIG. 6 is a front elevational view of the hand held evacuation device of FIG. 5 showing the pressure control feature in a different position.
FIG. 7 is a front perspective view of an embodiment of a rigid one-way valve element for use with flexible bags of the invention.
FIG. 8 is a rear perspective view of the one-way valve element of FIG. 7.
FIG. 9 is a cross-sectional view through the one-way valve element, as taken along line 9-9 of FIG. 7.
FIG. 10 is an exploded view of another embodiment of the one-way valve element made from pliable layers for attachment to the flexible bag.
FIG. 11 is an exploded view of another embodiment of the one-way valve element made from a single pliable layer for attachment to the flexible bag.
DETAILED DESCRIPTION OF THE
Now referring to the drawings, wherein like reference numbers refer to like elements, there is illustrated in FIG. 1 the various components that can be included in a storage system for the storage and/or preservation of items such as