Abstract:
A container and lid combination includes a container having a bottom surface, an opening, a top edge surrounding the opening, and an attachment mechanism provided on the bottom surface, and a lid engageable with the top edge of the container to cover the opening. The lid may include an attachment mechanism provided on its inside surface that is engageable with the attachment mechanism of the bottom surface of the container. The lid is attachable to the bottom surface of the container in a nested state via engagement of the respective attachment mechanisms. Another attachment mechanism may be provided on the outside surface of the lid that is engageable with the attachment mechanism of the bottom surface of the container. The lid is attachable to the bottom surface of the container in a nested state and/or in an inverted state via engagement of the attachment mechanisms. A set of such container and lid combinations may be nested together. Furthermore, in a set of container and lid combinations, the base of the container of one container and lid combination may be attachable to the outside surface of the lid of another container and lid combination, to facilitate transporting of the container and lid combinations.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     This invention relates to containers with lids. 
     2. Description of Related Art 
     Various types of lidded containers are known. Lidded containers are often sold in sets, and often each container of a set is of a different size such that the containers “nest” together, i.e., the smallest container fits inside the next-largest container, which in turn fits inside the next-largest container, and so on. 
     SUMMARY OF THE INVENTION 
     In such sets of containers, various problems are associated with management and storage of the lids. For example, the lids typically are stored separately from the containers, and often become lost. Additionally, when a particular lid is desired, the user must sort through the supply of lids to find the appropriate lid, which is troublesome. 
     This invention addresses these problems, and provides other advantages, by providing a container structure in which, when the container is not in use, the lid attaches to a bottom of the container. 
     In embodiments, the outside surface of the bottom of the container includes an attachment mechanism that attaches to a complementary attachment mechanism provided on an inside surface of the lid. 
     The outside surface of the lid may also include an attachment mechanism so that the lid may be attached to the container bottom in an inverted state. This inverted state of attachment is advantageous when, for example, the container and lid are placed together in a dishwasher for washing. The inverted state of attachment is also advantageous when, for example, multiple containers in an in-use state (e.g., a state of being filled with a food or other product) are stacked, one on top of another. In this state, the attachment mechanism of the bottom of the container on top may attach to the complementary attachment mechanism of the outside surface of the lid of the container below. 
     The attachment mechanisms may include a plurality of attachment projections. The attachment projections of the lid maybe angled toward the attachment portions of the container to provide a reliable engagement between the attachment projections of the lid and the attachment projections of the container. 
     These and other objects, advantages and salient features of the invention are described in or apparent from the following detailed description of exemplary embodiments. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Exemplary embodiments of the invention will be described with reference to the following drawings, wherein like numerals represent like parts, and wherein: 
     FIG. 1 is an oblique view of a first exemplary container according to the invention; 
     FIG. 2 is an oblique view of the container of FIG. 1 with a lid attached to the top thereof; 
     FIG. 3 is an oblique view of the container of FIG. 1 with the lid attached to the bottom surface thereof in an inverted state; 
     FIG. 4 is an oblique view of the container of FIG. 1 with the lid attached to the bottom surface thereof in a nested state; 
     FIG. 5 shows a cross section of a second exemplary container according to the invention with a lid attached to the bottom surface thereof in a nested state; and 
     FIG. 6 shows a cross section of a plurality of containers and lids according to the invention, in a nested state. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     This invention provides container lids that attach to an outside surface of a container bottom. 
     FIG. 1 shows a container  100 . The container is shown having a round shape in plan view, but any other desired shape, such as rectangular, square, triangular, pentagonal, etc. is also acceptable. The container  100  will typically be formed of plastic material. 
     The container  100  may include a ridge  120  provided around the outer periphery near a top edge of the container  100 . The ridge  120  reinforces the upper edge of the container  100  for greater strength and rigidity. The ridge  120  also facilitates closing of a lid, described below, onto the top edge of the container  100  by providing a structure for a user&#39;s fingers to anchor against while pressing the lid into sealing connection with the top edge of the container  100 . 
     Several notches  122  are preferably provided in the ridge  120 . The notches  122  allow the user&#39;s fingers easy access to the lid in order to remove the lid. The notches  122  also provide the advantage of allowing the outer circumference of the lid to be free of any protrusions such as are often present on prior art lids to provide a gripping ledge for a user&#39;s fingers. This facilitates nesting of the lids inside other containers, as described in more detail below. 
     The container  100  may also include one or more windows  124 . In the embodiment shown in FIG. 1, the windows  124  are formed as concave surfaces in the wall of the container  100 . However, any other desired configuration of the windows  124 , such as flat, convex, etc., is also acceptable. When the container  100  is formed of molded clear plastic, the transparency of the plastic may be reduced by slightly roughening the surfaces of the mold. The windows  124  may be made by, for example, polishing or grinding the corresponding portions of the mold very smooth relative to surrounding portions so that the resulting portions of the container  100  corresponding to the windows  124  are correspondingly smooth. This results in greater transparency at the windows  124  relative to the other portions of the container  100 . Therefore, the contents of the container  100  may be viewed without removing the lid. 
     As shown in FIG. 2, a lid  200  is provided that is sized and shaped such that its inner periphery engages the outer periphery of the top edge of the container  100  to effect a sealing relationship between the container  100  and the lid  200 . The inside surface of the lid  200  includes an attachment mechanism, described in more detail below, that engages a corresponding attachment mechanism provided on a bottom surface of the container  100 , also described in more detail below. The outside surface of the lid  200  may also include an attachment mechanism that engages the engagement mechanism on the bottom surface of the container  100 . In FIG. 2, the attachment mechanism on the outside surface of the lid  200  includes four attachment projections  212 . The attachment projections  212  are arcuate in shape, and together approximately define a circle. 
     As shown in FIG. 3, the attachment mechanism provided on the bottom surface of the container  100  includes a plurality of attachment projections  110 . The attachment projections  110  correspond in shape to the attachment projections  212  on the outside surface of the lid  200 . The attachment projections  212  frictionally engage the attachment projections  110  so that the lid  200  may be retained on the bottom of the container  100  in an inverted state. 
     Advantages of allowing the lid  200  to attach to the container  100  in an inverted state as shown in FIG. 3 include (1) the fact that, when placed in a dishwasher to be washed, the interior surfaces of both the container  100  and the lid  200  face outward and thus are better subjected to the cleaning action of the dishwasher; (2) the fact that, when a plurality of containers  100  and lids  200  are used, each being filled with a food or other product, the lid  100  of one container  200  may engage with the bottom surface of another container, thus locking the containers  100  and lids  200  together in a stacked relationship for easier carrying or the like; and (3) the fact that a container  100 , particularly a small container  100 , may be locked to its own lid  200  or the lid  200  of a larger container  100  in an inverted relationship for greater stability while being used as, for example, a serving dish. 
     As shown in FIG. 4, the lid  200  also is attachable to the bottom surface of the container  100  in a non-inverted state, hereafter called a nesting state. Specifically, as shown in FIG. 5, which shows a cross section of a second exemplary embodiment, attachment projections  210  are provided on an inside surface of the lid  200  and frictionally engage the attachment projections  110  provided on the bottom surface of the container  100 . 
     In the embodiment shown in FIG. 5, rather than a single set of each of the attachment projections  110 ,  210  and  212 , two sets of each are provided, respectively approximately defining concentric circles. While the extra sets of the attachment projections  110 ,  210  and  212  are not essential, they may provide advantages such as more secure attachment of the lid  100  to the container  100 . A further advantage of the second set of attachment projections  212 , in particular, is that the base of a small container may be attached to the lid of a large container, as described in more detail below. 
     As shown in FIG. 5, the attachment projections  110  on the base of the container  100  angle outward from the base of the container  100  away from the center of the container  100 , and the attachment projections  210  and  212  on the lid  200  angle inward from a top surface of the lid  200  toward the center of the lid  200 . This configuration allows more secure attachment of the lid  200  to the container  100 . 
     In FIG. 5, it can be seen that inward-facing sides of the attachment projections  210  and  212  of the lid  200  engage outward-facing sides of the attachment projections  110  of the base of the container  100 . In contrast, in FIG. 3, outward-facing sides of the attachment projections  212  are shown as engaging the inward-facing sides of the attachment projections  110 . It should be appreciated that either arrangement is acceptable. However, it will also be appreciated that, when the attachment projections  110 ,  210  and  212  are angled as shown in FIG.  5  and described above, the direction of the angle should be reversed if the outward-facing sides of the attachment projections  210  and/or  212  are to engage the inward-facing sides of the attachment projections  110 . 
     It should also be appreciated that, while the attachment projections  110 ,  210  and  212  have been described above as having an arcuate shape and approximately defining circles, many other shapes and configurations are possible. For example, the attachment projections  110 ,  210  and  212  may have a linear shape, with the attachment projections  110  on the bottom of the container  100  approximately defining a square, triangle, pentagon, hexagon, octagon or the like, and the attachment projections  210  and  212  on the lid  200  approximately defining corresponding squares, triangles, pentagons, hexagons, octagons or the like. 
     Additionally, although the attachment mechanisms described above have each included a plurality of attachment projections  110 ,  210  or  212 , it should be appreciated that each attachment mechanism alternatively may have only a single attachment projection, e.g., a continuous annular projection or the like. However, it is usually preferable for the attachment mechanism to include more than one attachment projection, for the following reasons. 
     First, if a single attachment projection is provided in the form of a continuous circle or the like, a “pool” will be formed by the attachment projection when the container  100  or lid  200  is, for example, placed upside down in a dishwasher. Water will collect in this “pool” during washing, which is annoying to a user who subsequently removes the container  100  or lid  200  from the dishwasher. In contrast, when a plurality of attachment projections are formed, as illustrated in the embodiments described above, a notch is formed between adjacent ones of the attachment projections  110 ,  210  or  212 . The notches allow water to escape, thus preventing ponding during washing. 
     Second, having a plurality of attachment projections  110 ,  210  or  212  allows the projections to deflect more resiliently and thus more easily engage opposing attachment projections  110 ,  210  or  212 . 
     FIG. 6 shows a cross section of a plurality of containers  100 - 105  nested together. Each container  100 - 105  has a corresponding lid  200 ,  201 ,  202 ,  203 ,  204  or  205  attached to its base in a nesting state by engagement of the attachment projections  110  with the attachment projections  210 . To enable connection between the base of one of the containers  200 - 205  and the lid  200 ,  201 ,  202 ,  203 ,  204  or  205  of one or more of the other containers  200 - 205 , the containers  100 - 105  and lids  200 - 205  have, insofar as is practical, the same configuration of the attachment projections  110 ,  210  or  212 . For example, as shown in FIG. 6, the attachment projections  110  of container  100  are identical in shape and position to the attachment projections  110  of containers  101 ,  102  and  103 , and the attachment projections  110  of container  105  are identical in shape and position to the attachment projections  110  of container  106 . 
     There are practical limits to making the attachment projections of each container have the same position, for the following reason. As can be appreciated from the drawings, each container  100 - 105  rests on the attachment projections  110  when placed on a horizontal surface. If attachment projections  110  are spaced too closely together on the base of the container  100 ,  101 ,  102 ,  103 ,  104  or  105  relative to the width of the base of the container, the container may not be sufficiently stable. On the other hand, in the case of the smaller containers in a set, e.g., containers  105  and  106 , the attachment projections  110  clearly cannot be spaced wider than the maximum width of the base of the container. 
     Accordingly, a suitable spacing width is selected for the attachment projections  110  on the largest container in a set, e.g., container  100 , and this spacing is maintained for each successively smaller container until such a spacing would no longer practically fit on the base of the container. Thus, for example, in FIG. 6, the spacing of the attachment projections  110  on container  100  is maintained for containers  101 - 103 , but would not fit on containers  104  and  105 ; therefore, a narrower spacing is used for containers  104  and  105 . An example of a suitable width of the spacing of the attachment projections  110  of the largest container  200  is greater than or equal to about one half of the width of base of the largest container  200 . 
     As shown in FIG. 6, the heights of the containers  100 - 105  are preferably selected such that, when the containers  100 - 105  are nested as shown, none of the top edges of containers  101 - 105  protrude above the plane of the top edge of container  100 . This allows the lid  200  to be placed on the top of the container  100  with all of the other containers  101 - 105  stored inside the container  100 . 
     In FIGS. 5 and 6, on each of the lids  100 - 105 , the attachment projections  210  on the inside surface of the lid are located at positions exactly opposite the positions of the attachment projections  212  on the outside surface of the lid. However, it is also acceptable for the attachment projections  210  on the inside surface of the lid to not be located at positions exactly opposite the positions of the attachment projections  212  on the other side of the lid. For example, the attachment projections  212  on the outside surface of the lid may approximately define a circle smaller than the circle approximately defined by the attachment projections  210  on the inside surface of the lid, and thus not be located exactly opposite the attachment projections  210 . 
     Considering the containers  100 - 105  in FIG. 6, it can be appreciated that, when the containers  100 - 105  are in use, with the lids  100 - 205  attached respectively to the top edges of the containers  100 - 105 , the bottom surfaces of only containers  101 - 104  can attach to the outer surface of the lid  200 , the bottom surfaces of only containers  100  and  102 - 104  can attach to the outer surface of the lid  201 , etc. Similarly, the bottom surface of only container  106  can attach to the outer surface of the lid  205 , and the bottom surface of only container  105  can attach to the outer surface of the lid  206 . However, if more than one set of attachment projections  212  are provided on at least the larger ones of the lids, e.g., lids  200 - 204 , as shown in FIG. 5, greater flexibility can result. Specifically, for example, if the lid  200  has two sets of attachments projections  212  as shown in FIG. 5, and if the inner set of attachment projections  212  match with the attachment projections  110  of the container  105  and/or  105 , then the container  105  and/or  106  can also be attached to the lid  200 . 
     Allowing the lids and containers to interchangeably interconnect as described above is particularly advantageous when, for example, multiple containers in an in-use state (e.g., a state of being filled with a food or other product) are stacked, one on top of another. In this state, the attachment mechanism of the bottom of the container on top may attach to the complementary attachment mechanism of the outside surface of the lid of the container below. For example, if the user is attending a party and taking chips in the container  100  and salsa in the container  104  or  106 , the user may stack the closed container  104  or  106  on the lid  200  of the closed container  100 . Since the respective attachment mechanisms mutually engage as described above, the user may easily carry both containers in one hand without fear of the top container sliding off of the bottom container. 
     While the invention has been described in conjunction with the specific embodiments described above, many equivalent alternatives, modifications and variations may become apparent to those skilled in the art once given this disclosure. Accordingly, the exemplary embodiments of the invention as set forth above are considered to be illustrative and not limiting. Various changes to the described embodiments may be made without departing from the spirit and scope of the invention.