Patent Publication Number: US-2012031907-A1

Title: Vented Container

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to disposable food containers used in Chinese take-out restaurants, and, more particularly, relates to a container that prevents accidental spillage of the liquid inside while allowing steam escaping relatively freely from the container. 
     Cooked foods generally contain solid substances, such as rice, meat and vegetable and liquid substances, such as oil, sauce and broth. In take-out restaurants, a food container used to store and transport such foods generally consists of a base portion and a lid portion made from a resilient polymeric material. On one hand, the lid has to be securely attached to the base to avoid accidental opening of the container and to prevent inside liquid from spilling out. On the other hand, in a closed environment, moisture generated and accumulated inside the container will quickly cause foods, especially vegetables, losing their original taste, texture and color. In order to prevent such thing from happening, people usually punch a hole through a container lid so that steam can escape from the inside of the container. However, the hole leaves a potential risk. In most case, a person buys a take-out food and will enjoy it later at another place. The irregular movement during carry often causes the liquid to jiggle and splash within the container. The jiggling and splashing can cause the liquid to spill out of the container and taint everywhere inside of the bag holding the container and other nearby items. 
     Many attempts have been made to provide a container and cover for preventing the splashing and spilling of liquids; however, such attempts have resulted in cups, containers, and covers that are expensive to produce, difficult and cumbersome to use, and/or inadaptable to the need in this situation. An example of a container lid that attempts to solve the splashing problem is shown in U.S. Pat. No. 4,795,052, issued Jul. 26, 1983 to Hayes. The Hayes lid disclosed a lid having a vent path, which has an inlet above and an outlet below the level of the lid. The path is constructed so that, as it extends from inlet to outlet, it traverses the lid from edge to axially opposing edge and back again. Although the Hayes lid solved the problem in his situation, it is inadaptable here since when the liquid flows into and blocks the path steam can no longer escape from the container, as Hayes described in his patent. Same problem exists in U.S. Pat. No. 5,988,426, issued to Stern. When the filter in the Stern patent, which is formed of a hydrophobic material and mounted over the vent hole, is tainted with liquids, its ventilating efficiency is greatly impaired. In addition, the cost of manufacturing such container in Stern is higher. U.S. Pat. No. 7,055,712, issued to Tang, disclosed a container for hot carry-out food includes a container body and a cover, each having flanges and the flanges defining a pair of seals between which is a condensation collecting chamber and radially outboard of an outermost seal is a second condensation collecting chamber which is continuously vented to atmosphere through radial venting passages or channels. Under elevated pressures, as might occur when hot food is packages in the container, the innermost seal opens permitting steam/gasses to vent into the innermost condensation collection chamber in which the steam might condense as condensate. Under higher internal container pressures, the outboard most seal may also open and vent gasses from the innermost condensation chamber through/into the outermost condensation collection chamber and continuously from the latter to atmosphere through a plurality of continuously open circumferential spaced radial venting passages or channels. Although a clever design, there are two problems in Tang&#39;s—(1) moisture can still be accumulated inside the container, and (2) the attachment between the lid and the base is not as secure as it should be. 
     It is, therefore, an object of the present invention to provide a container to prevent spilling of liquid from the container while allowing steam to escape relatively freely from the container. 
     Another object of the invention is to provide such a lid that is relatively simple and inexpensive to manufacture and to use. 
     SUMMARY OF THE INVENTION 
     In accordance with the above-stated objects, the present invention provides a vented container that consists of a lid and a base. The base has a planar bottom, base side walls extending vertically upward from said bottom, a base flange extending horizontally outward from said base side walls, an inverted, U-shaped base rim extending outward from said base flange, and multiple grooves of the same shape crossing horizontally on the top surface of said base rim. The lid has a planar top, lid side walls extending vertically downward from said top, a lid flange extending horizontally outward from said lid side walls, an inverted, U-shaped lid rim extending outward from said lid flange, multiple ridges, of a shape matching said grooves, crossing horizontally on the bottom surface of said lid rim, and a locking lip which extends vertically downward from said lid rim surface. Upon mating, multiple zip locks are formed between the lid rim and the base rim by grooves and ridges, and multiple channels are formed between said grooves and the bottom surface of said lid rim. In the preferred embodiment, grooves and ridges are arch-shaped, and the maximal diagonal of said channels is up to 1 millimeter, so that it prevents liquid from spilling out but allows steam pass through freely. 
     It is preferable that base and lid are stackable on a second base and lid, respectively, in order to save storing space. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The vented container of the present invention will be better understood by those of ordinary skill in the art and others upon reading the ensuing specification, when taken in conjunction with the appended drawings, wherein: 
         FIG. 1  is a perspective view of the lid and the base of the present invention wherein the lid is separate from the base, showing arch-shaped grooves and ridges; 
         FIG. 2  is a side view of the lid and the base mating together with removal of a portion of lid showing relative position between the lid and the base; 
         FIG. 3  is a detailed side view of a portion of the lid and the base mating together, showing zip locks and tiny channels formed between the lid and the base; 
         FIG. 4A  is a cross-sectional view of the mating edge between the lid and the base taken along section line  3 A- 3 A′ of  FIG. 3 , showing a zip lock formed between arch-shaped grooves and ridges; 
         FIG. 4B  is a cross-sectional view of the mating edge between the lid and the base taken along section line  3 B- 3 B′ of  FIG. 3 , showing a tiny channel formed between arch-shaped grooves and the bottom surface of the lid; 
         FIG. 4C  is a cross-sectional view of the mating edge between the lid and the base taken along section line  3 C- 3 C′ of  FIG. 3 ; and 
         FIG. 5  is an alternative view of  FIG. 4A , wherein the lid is separate from the base, showing an arch-shaped groove on the base rim and an arch-shaped ridge on the lid rim. 
     
    
    
     In the various figures of the drawings, like reference characters designate like parts. 
     DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT 
     In  FIG. 1 , it shows the perspective view of the lid and the base of the vented container, where the lid  10  is separate from the base  20 . The base  20  has a substantially planar bottom  21 , base side walls  22  extending substantially vertically upward from the bottom  21 , a base flange  23  extending substantially horizontally outward from the base side walls  22 , an inverted U-shaped base rim  24  extending outward from said base flange  23 , and multiple grooves  25  crossing horizontally on the top surface of said base rim  24 . the lid  10  has a substantially planar top  11 , lid side walls  12  extending substantially vertically downward from the top  11 , a lid flange  13  extending substantially horizontally outward from the lid side walls  12 , an inverted U-shaped lid rim  14  extending outward from the lid flange  13 , and multiple ridges  15  crossing horizontally on the bottom surface of said lid rim  14 . In general, the ridges  15  and the grooves  25  are same shape and are able to mate. The ridges  15  are fewer than the grooves  25 . In the preferred embodiment, both ridges  15  and grooves  25  are arch-shaped and the number of ridges  15  is half of that of grooves  25 . 
     In  FIG. 2 , it is a side view of the lid and the base mating together. A portion of the lid rim  14  is removed to show relative position between the lid and the base. In the preferred embodiment where the number of ridges  15  is half of that of grooves  25 , zip locks  31  are formed where ridges  15  mate with grooves  25  and channels  32  are formed where no ridges are present against grooves.  FIG. 3  is a detailed side view showing zip locks  31  and tiny channels  25  formed between the lid and the base. In the preferred embodiment, the maximal diagonal of said channels is less than 1 millimeter to prevent liquid from spilling out while allow stream passing through freely. 
       FIG. 4A  shows a cross-sectional view of the mating edge between the lid and the base taken along section line  3 A- 3 A′ of  FIG. 3 , showing a zip lock formed between an arch-shaped groove  25  and a ridge  15 .  FIG. 4B  is a cross-sectional view of the mating edge between the lid and the base taken along section line  3 B- 3 B′ of  FIG. 3 , showing a tiny channel formed between an arch-shaped groove  25  and the bottom surface of the lid. The inlet  33  connects to the inside of the container through a gap  35  between the lid rim and the base rim. The outlet  34  connects to atmosphere. Steam inside of the container can freely escape from the inlet  33  to the outlet  34 .  FIG. 4C  shows a cross-sectional view of the mating edge between the lid and the base taken along section line  3 C- 3 C′ of  FIG. 3 . 
       FIG. 4A-4C  also show a locking lip  36 , which extends vertically downward from said lid rim  14  and further securely holds the lid onto the base. 
       FIG. 5  is an alternative view of  FIG. 4A , where the lid is separate from the base, showing an arch-shaped groove on the base rim and an arch-shaped ridge on the lid rim. It is worth of noting that although the lid and the base shown here are manufactured by compression molding, other molding methods including injection can be used to produce the present invention. 
     While preferred embodiments of the invention have been discussed and illustrated, it should be understood by those of ordinary skill in the art and others that changes can be made to the illustrated embodiments without departing from the spirit and scope of the present invention. For example, the grooves and the ridges could be of other geometrical shape. Also, the number of grooves and ridges could be in other ratio. Since such changes can be made to the illustrated embodiments while remaining within the scope of the invention, the invention should be defined solely with reference to the appended claims.