Abstract:
The present invention relates generally to vacuum lids, and in particular, vacuum lids that are compatible with containers to preserve food stored in the container. An embodiment of the invention includes a top surface with an access aperture, a plurality of raised members of varying heights, and a removable raised member that covers a container valve. A vacuum is applied to the container valve, wherein air from the container is removed from the container. The container is then sealed with a membrane, thereby holding a vacuum inside the container.

Description:
CLAIM OF PRIORITY  
       [0001]    This application claims priority from provisional application entitled “REUSABLE VACUUM LID”, Application No. 60/271,119, filed Feb. 23, 2001, and which application is incorporated by reference. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates generally to vacuum lids. More particularly, the present invention relates to vacuum lids that are compatible with containers to preserve food stored in the containers.  
         BACKGROUND  
         [0003]    Vacuum packaging food maintains the freshness and flavor of the food three to five times longer than food packaged with conventional storage methods. This improvement is because the amount of oxygen available for interaction with the food is reduced as a result of the vacuum. Thus, microorganisms that require oxygen to grow, such as bacteria and yeast, affect food stored in a vacuum less than food stored using conventional methods. Additionally, vacuum packed foods that are frozen are less affected by freezer burn because there is less cold, dry air to dehydrate the food.  
           [0004]    The excess air that accompanies food packed using conventional packaging methods can have a variety of effects on the packaged food. For instance, dry foods can absorb moisture from the atmosphere, thereby becoming soggy. Yet, moist foods can become dry when packaged using conventional methods because air absorbs moisture from the moist food.  
           [0005]    An example of a dry food is sugar. When sugar is stored such that moisture from the air can be absorbed, the sugar can harden into a solid block. Such a block is unappealing at the very least. Furthermore, a pound of sugar in the form of a single block is very difficult to use. If the sugar had been packaged in a vacuum, then moisture from the atmosphere could not be absorbed by the sugar. Thus, the sugar would remain in granular form and not turn into a solid block.  
           [0006]    An example of a moist food is bread. When bread is stored in such a way as to allow exposure to the atmosphere, the bread tends to dry out and become hard and crusty. If, however, the bread was stored in a vacuumed packed storage container, then the atmosphere could not absorb the bread&#39;s moisture. Thus, the bread would maintain the proper amount of moisture and stay fresh and soft.  
           [0007]    Bread, however, also suffers from microorganisms like bacteria, yeast, and mold growths due to temperature changes and excess moisture. Storing bread with a conventional packaging method gives the microorganisms access to the atmosphere, thereby permitting the microorganisms to grow. Consequently, the bread becomes unsuitable for consumption. Storing the bread in a vacuum prevents the atmosphere from depositing any new microorganisms or reacting with any existing microorganisms. Thus, the vacuum packaging allows the bread to maintain its freshness.  
           [0008]    Yet another example of a food stored in conventional packaging devices is food that is high in fats and oils, such as butter. When food like butter is exposed to the atmosphere, over time becomes rancid, causing an unpleasant taste and smell. If the butter had been packaged in a vacuum, then the butter could not react with the atmosphere and turn rancid. Hence, the butter stored in a vacuum would remain fresh longer than if it had been packaged using a conventional packaging method.  
           [0009]    There are several types of home vacuum packaging systems currently available in the marketplace. For instance, there are manually operated vacuum pumps. These systems typically consist of a small, manually-operated pump which can be used to extract air from a container. Although they do not completely remove the air from the container, they do help food last longer. Another example of a home vacuum system is a bag sealer that includes a fan. Such a systems uses a small rotary fan to extract some air out of a plastic bag before the bag is sealed. Several different bag configurations are available in the market for such a bag sealer/fan system. For instance, one such system uses a polyethylene bags. Other bag sealer/fan system use sheets of plastic from which bags of different lengths can be made. This variable bag system “welds” the seams of the plastic sheets with a heated wire bag-sealing mechanism, thereby forming a closed bag. However, the fans in these home vacuum packaging systems do not have the ability to create a vacuum. This can be seen because the plastic used for the containers will loosely form around the contours of the food in the bag, but it will be obvious that air remains in the bag. Also, the strength of the seal and the material used for the bag in these home vacuum packaging systems will determine whether any air, atmosphere, or oxygen can re-enter the bag.  
           [0010]    Another type of home vacuum packaging systems uses an electric pump systems. These systems are the only storage systems that eliminate exposure to oxygen. They use electric-powered piston pumps to first extract air from a container. Then, the container is sealed to prevent any air, atmosphere, or oxygen from re-entering the sealed container. A consumer using such a home vacuum packaging systems can easily see that a vacuum is formed, when the container used to seal the food is a bag, because the bag will shape itself tightly around the food. Yet, when the container is more ridged, like a jar or a glass dish, a change in the physical shape of the container cannot be seen when the vacuum is present.  
         SUMMARY OF THE INVENTION  
         [0011]    It is an object of an embodiment of the present invention to create a vacuum lid compatible with, for example, ovenware containers and storage containers. Such a vacuum lid can be used to create a vacuum seal with the container, thereby preventing air from re-entering the container after being sealed. Another object of an embodiment of the invention is a vacuum lid that forms a container support surface when the lid seals the container under vacuum. The vacuum lid with a container support surface permits several containers to be stacked on top of each other where each container is covered with a vacuum lid. Yet another object of an embodiment of the present invention is a vacuum lid that is reusable. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    [0012]FIG. 1 depicts a top perspective view of an embodiment of the invention.  
         [0013]    [0013]FIG. 2 depicts a top perspective view of an embodiment of the invention illustrating an access aperture.  
         [0014]    [0014]FIG. 3 depicts a top perspective view of an embodiment of the invention illustrating a vacuum plug inserted into a removable raised member access aperture.  
         [0015]    [0015]FIG. 4 depicts a cross-section of an embodiment of the invention illustrating a gasket groove and a port valve assembly.  
         [0016]    [0016]FIG. 5A depicts a cross-section of an embodiment of the invention illustrating a container valve.  
         [0017]    [0017]FIG. 5B depicts a perspective view of an embodiment of a membrane of an embodiment of the invention.  
         [0018]    [0018]FIG. 6 depicts a partial cut-away view of an embodiment of the invention illustrating a container valve and a vacuum release device.  
         [0019]    [0019]FIG. 7 depicts another perspective view of the embodiment of the invention illustrated in FIG. 6.  
         [0020]    [0020]FIG. 8 depicts a cross-section of an embodiment of the invention that illustrates a container valve with a removable raised member and a vacuum plug.  
         [0021]    [0021]FIG. 9 depicts a top perspective view of a removable raised member of an embodiment of the invention.  
         [0022]    [0022]FIG. 10 depicts a bottom perspective view of a removable raised member of an embodiment of the invention.  
         [0023]    [0023]FIG. 11 illustrates a membrane of an embodiment of the invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0024]    [0024]FIG. 1 depicts a top view of an embodiment of the invention. A removable raised member  110 , a lid removal tab  112 , a multiple raised member  114  and a lid catch  115  are all part of a lid  100 . Lid  100  also includes a lid center  118 , a lid perimeter  120 , a top surface  122  and a bottom surface  123 . Through removable raised member  110  is a vacuum access aperture  111 .  
         [0025]    Referring to FIG. 1, the lid  100  is slightly curved such that the lid center  118  is above the lid perimeter  120 . The raised members  114  are of varying height extending above the top surface  122 . The raised member closest to the perimeter  120  are taller than the raised member at the lid center. The upper most surface of the raised member  114  and/or the removable raised member  110  is that surface that is furthest from the top surface  122 . The raised members  114  and removable raised member  110  are organized such that the upper most surface of each raised member  114  and removable raised member  110  form a container support surface which is preferably level or flat. The embodiment of the invention depicted in FIG. 1 shows eleven raised members  114  and one removable raised member  110 .  
         [0026]    In addition to providing the flat surface, removable raised member  110  also provides access through the lid  100  to a container upon which the lid  100  is affixed. In conjunction with the flat surface defined by the upper most portion of raised member  114  and removable raised member  110 , the lid catch  115  provides support to a second container that can be stacked on top of lid  100 . The lid removal tap  112  provides a device to disengage lid  100  from a container with which lid  100  is connected.  
         [0027]    The lid  100 , raised member  114  and removable raised member  110  can be made from materials that are generally ridged, but have some flexibility. Some such materials include polycarbonate and ABS plastic.  
         [0028]    An alternate embodiment can include a removable raised member  110 , that covers a substantial part of the lid  100  and no raised members  114 . Thus, a flat surface can be provided by the removable raised member  110 , itself. Another embodiment of the invention, however, can have the above enlarged removable raised member  110  and the lid perimeter  120  define a container support surface.  
         [0029]    While the raised members  114  in FIG. 1 are circular in shape at their upper most surface, in an alternate embodiment, the raised members can be any other shape such as triangles, squares, rectangles, pentagons, stars, trees, leaves, pumpkins, clovers, hearts, etc. In yet another embodiment of the invention, the raised members can be ridges. For instance, a star shape pattern can be formed such that the center of the star pattern could begin at the lid center  118 , or any other location on the lid  100 , with the rays of the star being of varying height and covering the top surface  122 , thereby forming a container support surface defined by the upper most portion of the star rays. Parallel ridges can also be provided which have less height at the center  118  and greater height about equal to the height of the lid catch  115  as the ridge approach the periphery of the lid  100 .  
         [0030]    In yet another embodiment of the invention, the lid  100  is flat such that the lid center  118  is generally on the same plane as the lid perimeter  120 . In yet another embodiment of the invention, the upper most surface of raised members  114  and removable raised member  110  can form a plane when the lid  100  is connected with a container and a vacuum formed within the container.  
         [0031]    [0031]FIG. 2 depicts a top view of the embodiment of the invention of FIG. 1 illustrating an access aperture. An access aperture  209 , a lid removal tab  212 , and raised members  214  are all part of lid  200 . The access aperture  209  provides access through lid  200  to a container that lid  200  is secured to. As in FIG. 1, a removable raised member  110  can cover the access aperture  209 . It is between the removable raised member  110  and the access aperture  209  that the valving mechanism of the invention resides.  
         [0032]    [0032]FIG. 3 depicts a top view of an embodiment of the invention, similar to FIGS. 1 and 2, illustrating a removable vacuum probe  316  inserted into a removable raised vacuum member access aperture. Removable vacuum probe  316  is connected with a source of vacuum for evacuating a container to which the lid  300  is affixed. Lid  300  has, in addition, raised members  314 , lid removal tabs  312  and removable raised member  310 .  
         [0033]    [0033]FIG. 4 depicts a cross-section of an embodiment of the invention illustrating a gasket groove and a port valve assembly. Lid  400  includes a lid top  401 , a bottom surface  423 , a gasket groove  132 , an access aperture  409 , raised members  414  and a removable raised member  410 . Removable raised member  410  includes a vacuum release device  460 . Removably insertable into the removable raised member  410  is a vacuum probe  416 . Vacuum probe  416  includes a vacuum nose port  430 . The access aperture  409  includes an access port  434 . Connected with the access aperture  409  is a membrane  426 . Membrane  426  is connected with a membrane stem  428  that extends through access aperture  409 . All of the above features are depicted in greater detail in FIGS. 5 and 5A.  
         [0034]    Gasket groove  432  provides a place for a gasket to connect with lid  400 . The gasket improves the seal between lid  400  and a container connected with lid  400 . The gasket is approximately equal to the circumference of the container shape. The better the seal between lid  400  and a container connected with lid  400 , the better that a vacuum can be created inside the container.  
         [0035]    [0035]FIG. 5A depicts a cross-section of an embodiment of the invention similar to FIGS.  1  to  4  illustrating the container valve  536 . Lid  500  has raised members  514 , the removable raised member  510  and the container valve  536 . A vacuum probe  516  that includes a vacuum nose  530  is removably connected with the removable raised member  510 . Typically vacuum probe  516  is permanently connected to a base which communicates with a source of vacuum. A vacuum channel  538  extends through the vacuum probe  516  and the vacuum nose  530  allowing access to the container valve  536 . The container valve  536  includes a membrane  526 . Connected with membrane  526  is a membrane stem  528  that extends through lid  500  by way of an access port  534 . Membrane stem  528  fits loosely in a access port  534 . Stopper  538  keeps membrane  526  in place. The membrane  526  can be manufactured from any number of different flexible materials. One such material is rubber.  
         [0036]    In operation, vacuum probe  516  is connected with a vacuum that draws air through the container valve  536  and out of a container for which lid  500  is connected. As the vacuum is applied, membrane  526  is drawn towards the vacuum nose  530 . Consequentially, membrane  526  permits air from the container to pass through access port  534  out of the container. Membrane stem  528  restricts the movement of membrane  526  such that membrane  526  does not come into a sealing engagement with the vacuum probe  516 . After air is removed from the container, the vacuum source is disengaged, causing membrane  526  to be drawn back towards the container by the vacuum created in the container. Membrane  526 , however, is prevented from fully entering the container by the size of the access port  534 . As membrane  526  settles into place as a result of being drawn towards the container, a seal is formed with membrane  526  over access port  534 , thereby sealing the container that now has a vacuum inside. It is also to be understood that in addition bores  539  can be provided in lid  500  or under the membrane  526 . These bores also provide access to the inside of the container to which lid  500  is affixed. A vacuum can be drawn through bores  539  and when the vacuum source is turned off, the membrane  526  is drawn down by the vacuum inside of the container sealing off the bores  539 .  
         [0037]    [0037]FIG. 5B depicts a perspective view of an embodiment of a membrane of an embodiment of the invention similar to membrane  526 . Membrane  540  is coupled with a membrane stopper  544  by a membrane stem  542 . Assuming membrane  540  replaced membrane  526  in FIG. 5, membrane  540  is proximate to a first end of access port  534 , membrane stem  542  is inside the access port  534 , and membrane stopper  544  is proximate to a second end of access port  534 . When a vacuum is applied through vacuum probe  516 , membrane  540  can move towards vacuum probe  516 . Membrane stopper  544  prevents membrane  540  from making a seal with vacuum probe nose  536 . When the vacuum is removed, then membrane  540  seals access port  534  and prevents air from returning to the container. In one embodiment of the invention, the membrane  540  is generally cup shaped. In another embodiment of the invention, the membrane  540  is a generally flat surface.  
         [0038]    [0038]FIG. 6 depicts a partial cut-away view of an embodiment of the invention similar to FIG. 5 illustrating part of a container valve and a vacuum release device. A vacuum release device  650  is connected with a removable raised member  610  that includes a vacuum access port  648 . The vacuum access port  648  provides access to a container valve  636 . Container valve  636  includes a membrane  626  that is connected with a membrane stem  648 . Vacuum access port  648  provides access for a vacuum probe such as vacuum probe  516  from FIG. 5. To break the seal that the container valve  636  makes with a container, the vacuum release device  650  is positioned to make contact with membrane  626 . The membrane  626  is flexible such that once a predetermined force is applied by the vacuum release device  650  onto the membrane  626 , then the membrane  626  deforms. The seal that the membrane  626  had previously made is then broken. Air can then return to the container from the atmosphere.  
         [0039]    In one embodiment of the invention, the removable raised member  610  can rotate. In this embodiment, as the removable raised member  610  rotates, the vacuum release device  650  rotates. Through the rotation of the removable raised member  610 , and consequentially the vacuum release device  650 , contact is made with the membrane  626  by the vacuum release device  650 . Continued rotation of the removable raised member  610  causes the vacuum release device  650  to push against the membrane  626  and thus the seal formed by the total membrane  626  to be broken, thereby exposing the container to the atmosphere. In one embodiment of the invention, the removable raised member  610  is rotated approximately by 25 degrees. Other embodiments can have rotations up to about 90 degrees. Although not depicted in FIG. 6, it is understood that a bead and recess arrangement can be formed between the removable member  610  and the lid to allow the removable member  610  to snap onto the lid and guide the removable member  610  as it rotates relative to the lid. For example, in FIG. 5A a guide  562  is formed in the inside of the skirt of removable raised member  510  and a recess  563  is formed in an upstanding collar  565  of the lid  500 .  
         [0040]    In yet another embodiment of the invention, the vacuum release device is a handle that extends through the removable raised member  610  such that the handle is accessible without removing the removable raised member  610  from a lid. In one embodiment of the invention, the handle can slid, thereby sliding the vacuum release device  650 , such that the vacuum release device  650  makes contact with and deforms member  626 , thereby breaking the seal and exposing the contents of the container to air in the atmosphere. In another embodiment of the invention, the vacuum release device  650  does not deform membrane  626 , but rather, moves the membrane  626  such that an access port is exposed. Exposure of the access port permits air to enter the container from the atmosphere, thereby terminating the vacuum in the container.  
         [0041]    [0041]FIG. 7 depicts another perspective view of the embodiment of the invention illustrated in FIG. 6. Shown are a removable raised member  610  that includes a vacuum access port  648 . The removable raised member  610  is connected with a vacuum release device  650 . Container valve  636  includes a membrane  626  that is connected with a membrane stem  628 .  
         [0042]    [0042]FIG. 8 depicts a cross section of an embodiment of the invention that illustrates a container valve with a removable raised member and temporarily positioned vacuum probe. A lid  800  is coupled with a container  858 . A removable raised member seal  856 , such as for example a gasket, couples a removable raised member  810  with the lid  800 . Connected with the removable raised member  810  is a vacuum release device  850 . The removable raised member  810  includes a vacuum port  848 . A vacuum probe  816  that includes a vacuum nose  830  is temporarily connected with the removable raised member  810 . The container valve includes a membrane  826 . A membrane stem  828  couples the membrane  826  with a membrane stopper  844 . The membrane  826  is connected with the lid  800  such that air flowing in either direction through an access port  834  is controlled.  
         [0043]    The container valve  838  performs similarly to the container valves of FIG. 5, FIG. 6 and FIG. 7. Thus, as a vacuum source is connected with the vacuum probe  816 , the membrane  826  is drawn towards the vacuum nose  830 . Consequently, access port  834  is exposed allowing air to flow out of the container  858 . When the vacuum source is disengaged from the vacuum probe, the membrane  826  seals the container valve  836 , holding the vacuum inside the container  858 . As in other embodiments, the membrane stopper  844  prevents the membrane  826  from making a seal with the vacuum probe  816  when a vacuum is connected with vacuum probe  816 .  
         [0044]    [0044]FIG. 9 depicts a top view of a removable raised member of an embodiment of the invention. Shown in FIG. 9 is a removable raised member  910  that includes a vacuum port  948 . A lever  960  is connected with removable raised member  910 . The lever  960  provides a device for rotating the removable raised member  910 .  
         [0045]    [0045]FIG. 10 depicts a bottom view of a removable raised member of an embodiment of the invention. A removable raised member  1010  includes a vacuum port  1048 . A removable raised member  1010  is connected with a lever  1060 , a vacuum release device  1050  and a guide  1062 . The vacuum port  1048  provides access for a vacuum plug similar to the vacuum probe  816  of FIG. 8. The lever  1060  provides a device for rotating removable raised member  1010 . Vacuum release device  1050  provides a device for releasing the vacuum inside a sealed container.  
         [0046]    [0046]FIG. 11 illustrates an alternative membrane of an embodiment of the invention. A membrane stem  1128  couples a membrane  1126  with a membrane stopper  1144 . The membrane includes a plurality of fins  1166  separated by a groove  1168 . The fins  1166  are spaced along the perimeter of the membrane  1126  and generally extending upwardly from the membrane  1126  and away from the membrane stopper  1144 . The membrane  1126  can also be described as having a shape similar to the crown.  
         [0047]    It is to be understood that all of the above embodiments are disassembleable for cleaning by the user.  
         [0048]    The foregoing description of preferred embodiments of the present invention has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations will be apparent to the practitioner skilled in the art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, thereby enabling others skilled in the art to understand the invention for various embodiments and with various modifications that are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalence.