Abstract:
A preservation container cover includes a flexible film to contact with the rim of the container, an upper sealing ring, and a lower sealing ring affixing a periphery portion of the flexible film. The upper sealing ring has a ring slot extending along the periphery portion of the flexible film. The lower sealing ring comprises a ring plug along the periphery portion of the flexible film. The ring slot and the ring plug form a clamp structure to affix the flexible film. The present invention is convenient to use, adaptable to various containers of different types and sizes, and won&#39;t cause waste of natural resources and environment problems.

Description:
BACKGROUND OF THE PRESENT INVENTION 
       [0001]    1. Field of Invention 
         [0002]    The present invention relates to a cover for preservation containers, and more particularly to a preservation container cover which is flexible to preservation containers of different sizes and types. 
         [0003]    2. Description of Related Arts 
         [0004]    It is well known that the cover of a preservation container must fit the opening of the preservation container. Therefore, for a plurality of containers with different sizes, each of the containers must be provided with a specific cover correspondingly to prevent leaking. In other words, each kind of containers must use its own cover. 
         [0005]    However, there are many containers that do not have their own covers. For these containers, different methods for preventing leakage of the food stored therein are used. For example, ethylene resin wrap is widely used in restaurants and families to seal bowls or other containers to prevent the food contained therein, such as hot soup, from leaking 
         [0006]    In fact, the wrap or cling film for packing is a disposable product that results a great unnecessary waste to natural resources. Additionally, the wrap is easy to be broken, so a large amount is needed to wrap firmly. Other problems include the hot soup in the container can easily break the wrap and the wrap is not easy to remove after heated. 
         [0007]    In addition, the packing wrap is merely for one-time used, producing large quantities of waste. This waste is not easy to degrade and causes serious environmental problems. 
       SUMMARY OF THE PRESENT INVENTION 
       [0008]    According to the problems mentioned above, an object of the present invention is to provide a preservation container cover which is convenient to use, suitable for various containers of different types and sizes, and avoids the wasting of natural resources and environmental problems. 
         [0009]    To accomplish the above object, the present invention provides a preservation container cover, comprising a flexible film to contact with a rim of a container, an upper sealing ring, and a lower sealing ring affixing a periphery of the flexible film. 
         [0010]    In one embodiment of the present invention, the upper sealing ring has a ring slot along the periphery of the flexible film, the lower sealing ring comprises a ring plug along the periphery of the flexible film, and the ring slot and the ring plug form a clamp structure to affix the flexible film. 
         [0011]    In the present invention, the upper sealing ring, the flexible film, and the lower sealing ring are rigidly connected by fusing to form a firm and reliable connection. 
         [0012]    In the present invention, the upper sealing ring comprises an upper shoulder corresponding to the edge of the flexible film and the lower sealing ring comprises a lower shoulder corresponding to the edge of the flexible film, wherein the upper shoulder and the lower shoulder form a clamp structure to affix the edge of the flexible film. 
         [0013]    In the present invention, the lower shoulder of the lower sealing ring has a slot, wherein a bottom sealing ring is embedded in the slot and the extruding portion of the lower bottom sealing ring forms an expanding element of the lower shoulder of the lower sealing ring. 
         [0014]    In the present invention, the flexible film comprises an extending portion extending outwardly from the rim of the container and extending portion forming a vacuum releasing structure of the flexible film which is used to release the vacuum after a vacuum sealing the container. 
         [0015]    In the present invention, the upper sealing ring comprises a handle at the position of the extending portion of the flexible film, wherein the handle is corresponding to the vacuum releasing element for applying an upward force to the vacuum releasing element of the flexible film to release the vacuum. 
         [0016]    In the present invention, the flexible film is made of thermoplastic material. 
         [0017]    In the present invention, the thermoplastic material is selected from the group consisting of polycarbonate, polyethylene, polyvinylidene chloride, or propylene which is non-toxic to human body. 
         [0018]    The advantages of the present invention include the following: 
         [0019]    1) The preservation container cover has no limitation to the type and size of the container. 
         [0020]    2) The cover can conveniently seal the container by vacuum and be removed from the container. 
         [0021]    3) Unlike the wrap, the cover of the present invention can be reused and won&#39;t cause wasting natural resources and environmental problems. 
         [0022]    4) The container sealed by the cover of the present invention can be heated by microwave directly and conveniently to cook or heat the stuff inside the container. 
         [0023]    Accordingly, the present invention is convenient to use, adaptable to containers of different types and sizes, and won&#39;t cause resource wasting and environment problems. 
         [0024]    In one embodiment, the present invention provides a preservation container cover which comprises a flexible film to contact with an upper rim of a container, an upper ring, and a lower ring adapted to affix a periphery of the flexible film. The upper ring comprises an inner block ring and an outer block ring, wherein the inner block ring and the outer block ring form a clamp ring which has an opening thereof facing downward and a cross section having a “U” shape. The lower ring comprises an inner expanding ring and an outer expanding ring. The inner expanding ring and the outer expanding ring form an expanding ring with an opening thereof facing upward, wherein a cross section of the expanding ring is in a “U” shape. The opening of the clamp ring and the opening of the expanding ring are facing each other and coupled by clamping and expanding which affixes the periphery of the flexible film. Because of the coupling between the clamp ring and the expanding ring with the “U” shape cross section, the problems of the conventional two rings structure, such as loose sealing of the periphery of the flexible film and sliding of the flexible film, are solved. 
         [0025]    In an alternative mode of the present invention, the inner expanding ring comprises a shoulder corresponding to the press surface of the inner block ring. The shoulder further comprises a conical ring integrally extended from the shoulder wherein the conical ring is plugged into the inner wall of the inner block ring. The shoulder and the press surface provide a vertical pressure to the periphery of the flexible film, and the conical ring provides an inner tilt pressure to the periphery of the flexible film. 
         [0026]    In the present invention, the outer expanding ring comprises a conical expander which further provides an outer tilt pressure to the periphery of the flexible film. 
         [0027]    In the present invention, the outer block ring comprises a loop on the inner wall thereof, wherein the loop limits the position of the terminal of the conical expander of the outer expanding ring. Because the loop provides the limit to the terminal of the expander of the conical ring, the expanding ring can be plugged into the opening of the clamp ring and is not easy to be detached. 
         [0028]    In the present invention, the handle of the upper ring comprises a date indicator for indicating the preservation period. 
         [0029]    In the present invention, the flexible film comprises an extension extending from the rim of the container outwardly. T he extension forms the vacuum releasing element for detach the flexible film from the rim of the container after the container is vacuum sealed. 
         [0030]    The benefits of the present invention further include the following: 
         [0031]    1) Simple structure: the cover only comprises three parts which are the upper ring, the lower ring, and the flexible film. The upper ring and the lower ring are plastic molded. 
         [0032]    2) Easy to fabricate: use the upper ring and the lower ring to press the periphery of the flexible film; the clamp ring and the expanding ring act as the affixing component to clamp the flexible film in merely one step. 
         [0033]    The opening of the clamp ring and the opening of the expanding ring are facing each other and coupled by clamping and expanding which affixes the periphery of the flexible film. Because of the coupling between the clamp ring and the expanding ring with the “U” shape cross section, the problems of the conventional two rings structure, such as loose sealing of the periphery of the flexible film, and sliding of the flexible film, are solved. It also skips the conventional second step of fusing the two rings structure with the flexible film. 
         [0034]    3) Environmentally friendly and durable: not like the disposable one-time used wrap, the present invention can be re-used, and will not cause waste of natural resources and environment problems. 
         [0035]    4) Universal application: can be used for different types of containers such as class, ceramic, plastic, metal containers with shape of round or rectangular. 
         [0036]    5) High adaptability: can be used for containers with different sizes, shapes, and materials. 
         [0037]    6) Easy to operate: push to seal; pull to release; can be operated by one hand. 
         [0038]    Therefore, the present invention is simple, easy to fabricate, durable, environment friendly, universally usable, highly adaptable and easy to use. It is adapted to all kinds of preservation containers. 
         [0039]    These and other objectives, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0040]      FIG. 1  is a perspective view of an assembled embodiment of the present invention. 
           [0041]      FIG. 2  is a sectional view of an embodiment of the present invention. 
           [0042]      FIG. 3  is an enlarged perspective view of part A of the  FIG. 2 . 
           [0043]      FIG. 4  is an enlarged perspective view of part B of the  FIG. 2 . 
           [0044]      FIG. 5  is a perspective view of separated parts of an embodiment of the present invention. 
           [0045]      FIG. 6  is a sectional view of the parts in  FIG. 5 . 
           [0046]      FIG. 7  is a perspective of another embodiment of the present invention. 
           [0047]      FIG. 8  is a top view of the embodiment in  FIG. 7 . 
           [0048]      FIG. 9  is a sectional view of the embodiment along the line A-A in  FIG. 8 . 
           [0049]      FIG. 10  is a perspective view of the upper ring. 
           [0050]      FIG. 11  is a perspective view of the lower ring. 
           [0051]      FIG. 12  is an expanded view of the part B in  FIG. 10 . 
           [0052]      FIG. 13  is an expanded view of the part C in  FIG. 11 . 
           [0053]      FIG. 14  is a perspective view of the clamp ring and the expanding ring illustrating the affixing of the flexible film. 
           [0054]      FIG. 15  is a perspective view of the parts in  FIG. 7 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0055]    Referring to  FIGS. 1 to 6 , an embodiment of the present invention of a preservation container cover comprises a flexible film  2  adapted to contact with a rim of a container (not shown in Figures), an upper sealing ring  1  and a lower sealing ring  3 , wherein the upper sealing ring  1  and the lower sealing ring are adapted to affix a periphery portion  21  of the flexible film  2 . The upper sealing ring  1  has a ring slot  11  provided along the periphery portion  21  of the flexible film  2 . The lower sealing ring  3  comprises a ring plug  31  extended along the periphery portion  21  of the flexible film  2 . The ring slot  11  and the ring plug  31  forms the clamp structure to affix and retain the periphery portion  21  of the flexible film  2  in the ring slot. The upper sealing ring  1 , flexible film  2 , and the lower sealing ring are firmly and rigidly connected together by fusing. The upper sealing ring  1  comprises an upper shoulder  12  corresponding to an edge portion  22  of the flexible film  2  and the lower sealing ring comprises a lower shoulder  32  corresponding to the edge portion  22  of the flexible film  2 , wherein the upper shoulder  12  and the lower shoulder  32  form a clamp construction to affix the edge portion  22  of the flexible film  2  in position. The lower shoulder  32  of the lower sealing ring  3  has an insertion slot  33  provided therearound, wherein a bottom sealing ring  4  is embedded in the insertion slot  33 . An extruding portion  41  of the lower bottom sealing ring  4  forms an expanding structure of the lower shoulder  32  of the lower sealing ring  3 . The flexible film  2  has an extending portion  23  extending beyond from the rim of the container, the extending portion  23  is constructed as a vacuum releasing element of the flexible film  2  which is used to release the vacuum after vacuum sealing the container. The upper sealing ring  1  comprises a handle  13  with respect to the extending portion  23  of the flexible film  2 , so that the handle  13  is able to apply an upward force to the vacuum releasing portion of the flexible film  2  for releasing the vacuum. The flexible film  2  is made of thermoplastic material, selected from a group consisting of polycarbonate, polyethylene, polyvinylidene chloride, and propylene, which is non-toxic to human body. 
         [0056]    The operation and principle of the cover of the present invention are described hereinafter. The cover is adapted to be used with all kinds of container, regardless of the types and sizes thereof, as long as the cover is larger than the opening of the container. Vacuum sealing: slightly push down the flexible film  2  of the cover softly that squeezes the air out of the container from its rim, the flexible film  2  and the container are sealed by vacuum. Vacuum releasing: to press the handle  13  with a thumb while pressing the extending portion  23  of the flexible film  2 , i.e. the vacuum releasing portion, the air is able to enter into the container while pulling the extending portion  23 , so that the vacuum is released and the cover can be removed. 
         [0057]    In the present invention, the shape of periphery of the cover can be circular which is close to the shape of the container, or can be oval, rectangular, square, or other polygon. Of course, it can also be other shape which is not mentioned above. 
         [0058]    Referring to  FIGS. 7 to 15 , in an alternative embodiment of the present invention, the cover comprises an upper ring  1 ′, a flexible film  2 ′, and a lower ring  3 ′. The upper ring  1 ′ comprises an inner block ring  11 ′ and an outer block ring  13 ′. The inner block ring  11 ′ and the outer block ring  13 ′ form a clamp ring  12 ′ with an opening thereof facing downward, wherein a cross section of the clamp ring is in a “U” shape. The lower ring  3 ′ comprises an inner expanding ring  31 ′ and an outer expanding ring  33 ′. The inner expanding ring  31 ′ and the outer expanding ring  33 ′ form an expanding ring  32 ′ with an opening thereof facing upward, wherein a cross section of the expanding ring  32 ′ is in a “U” shape. The opening of the clamp ring  12 ′ and the opening of the expanding ring  32 ′ are facing each other and coupled by clamping and expanding which affixes the periphery portion  21 ′ of the flexible film  2 ′. The inner expanding ring  31 ′ comprises a shoulder  311 ′ corresponding to the press surface  111 ′ of the inner block ring  11 ′. The shoulder  311 ′ further comprises a conical ring  312 ′ integrally extended from the shoulder  311 ′, wherein the conical ring  312 ′ is plugged into the inner wall of the inner block ring  11 ′. The shoulder  311 ′ and the press surface  111 ′ provide a vertical pressure to the periphery portion  21 ′ of the flexible film  2 ′, and the conical ring  312 ′ provides an inner tilt pressure to the periphery portion  21 ′ of the flexible film  2 ′. The outer expanding ring  13 ′ comprises a conical expander  331 ′. The expander  331 ′ further provides an outer tilt pressure to the periphery portion  21 ′ of the flexible film  2 ′. The outer block ring  13 ′ comprises a loop  14 ′ on the inner wall thereof, wherein the loop  14 ′ limits the position of the terminal  332 ′ of the conical expander  331 ′ of the outer expanding ring  33 ′. Because the loop  14 ′ provides the limit to the terminal  332 ′ of the conical expander  331 ′ of the outer expanding ring  33 ′, the expanding ring  32 ′ can be plugged into the opening of the clamp ring  12 ′ that is not easy to be detached. The handle  15 ′ of the upper ring  1 ′ comprises a date indicator  4 ′ for indicating the preservation period. The flexible film  2 ′ comprises an extending portion  22 ′ extending beyond the rim of the container outwardly. The extending portion  22 ′ forms a vacuum releasing element for detaching the flexible film  2 ′ from the rim of the container after the container is vacuum sealed. 
         [0059]    In the present invention, the flexible film  2 ′ is generally made of high-quality polymeric materials such as polystyrene. 
         [0060]    The operation and principle of the cover of the present invention are described hereinafter. The cover is adapted to all kinds of container regardless of types and sizes thereof, as long as the cover is larger than the opening of the container. Vacuum sealing: slightly push down the flexible film  2  of the cover softly to squeeze the air out of the container from the rim thereof, the flexible film  2  and the container are sealed by vacuum. Vacuum releasing: to press the handle  13  by the thumb while pressing the extending portion  23  of the flexible film  2 , i.e. the vacuum releasing element, the air is able to enter into the container by pulling the extending portion  23  so as to release the vacuum and remove the cover. 
         [0061]    One skilled in the art will understand that the embodiment of the present invention as shown in the drawings and described above is exemplary only and not intended to be limiting. 
         [0062]    It will thus be seen that the objects of the present invention have been fully and effectively accomplished. It embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.