Abstract:
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 outboardmost 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.

Description:
BACKGROUND OF THE INVENTION 
   The invention is directed to a container defined by a container body and a cover or lid which can be applied to and removed from the container body. The container is particularly adapted for use with so-called carry-out and fast-food restaurants, such as might be associated with Chinese carry-out food. Typical containers associated with fast-food/carry-out restaurants include: 
   
     
       
             
             
             
           
         
             
                 
                 
             
           
           
             
                 
               D466,808S 
               Liu et al. 
             
             
                 
               D467,497S 
               Liu et al. 
             
             
                 
               5,685,478 
               Tang 
             
             
                 
               6,056,138 B1 
               Chen 
             
             
                 
               6,196,404 B1 
               Chen 
             
             
                 
                 
             
           
        
       
     
   
   The following patents and published patent applications represent the scope and content of the prior art as reflected by a search of the prior art with respect to the invention disclosed herein: 
   
     
       
             
             
             
           
         
             
                 
                 
             
           
           
             
                 
               US2002/0162846 Al 
               Mercier 
             
             
                 
               US2003/0168465 Al 
               Breimon et al. 
             
             
                 
               US2003/0183641 Al 
               Asbury 
             
             
                 
               2,275,970 
               Tupper 
             
             
                 
               2,816,589 
               Tupper 
             
             
                 
               3,511,288 
               Swett et al. 
             
             
                 
               3,957,097 
               Swett 
             
             
                 
               4,027,778 
               Tupper 
             
             
                 
               4,466,552 
               Butterworth et al. 
             
             
                 
               4,561,562 
               Trombly 
             
             
                 
               4,765,506 
               Fishman et al. 
             
             
                 
               5,356,026 
               Andress et al. 
             
             
                 
               5,695,086 
               Viola 
             
             
                 
               6,307,603 
               Swett 
             
             
                 
                 
             
           
        
       
     
   
   Conventional carry-out containers made from plastic material utilize a plastic cover which is snap-secured to a plastic container at peripheral edges of flanges thereof. Such flanges generally include at least one circumferential seal which prevents product spillage/leakage. If such seals fail, the product within the container will leak outwardly therefrom onto surfaces which are then soiled/damaged, such as a person&#39;s clothing, upholstery/carpeting when in transit in an automobile, etc. Such containers are stacked upon each other for home delivery from carry-out restaurants, and even if the seal between the cover and the container remains unbroken, another problem is the tendency of the sealed container to bulge under internal pressure, such as steam emanating from hot packaged products. Normally, such containers include stacking or nesting features, and if the steam is not dissipated or vented, end panels and bottom panels of the respective covers and containers bulge, the stacking features become ineffective, and containers can abruptly unstack, fall, burst open, and thereby cause damage to such surfaces as clothing, floors, automotive interiors, etc. At times, seals which unseal may not cause product spillage/leakage/damage, yet dissipate heat rapidly which in turn results in the food becoming cool and the latter in turn necessitates at-home re-heating before eating. Obviously, re-heating a food product renders it less tasty. If leakage occurs while such containers packaged with hot food are being carried in paper or plastic bags, it is not uncommon for paper bags to weaken and burst, while plastic bags collect the leakage/spillage creating a mess at the time of unpacking and serving. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention is directed to a container particularly adapted for housing hot products, such as Chinese food or the like, delivered from so-called fast-food/carry-out establishments, which will prevent spillage, provide limited and controlled venting and also retain heat through a novel multiple seal system between opposing flanges of a container body and an associated cover which are snap-secured to each other. 
   In further accordance with the invention, flanges of the cover and container body include a minimum of two substantially concentric peripheral seals in the form radially spaced beads and a condensate collecting channel therebetween. The flanges are also inter-lockingly secured to each other which assures that the sealing beads remain sealed at each side of the condensation collecting channel, except for controlled venting which prevents the disadvantages earlier described with respect to conventional containers used in hot food carry-out restaurants. 
   Preferably, the flanges of the cover and container body include a pair of radially spaced substantially concentric seals in the form of two sealing beads in opposing interengaging sealing relationship with two sealing surfaces collectively assuring the absence of product leakage and the maximization of heat retention. A condensation collection channel is formed in the flange of the container, opens upwardly toward the flange of the cover, and is located between the two sealing beads which can be located on either the cover flange, the container flange or one sealing bead on each. Under optimum conditions when a hot food product is packaged in a container and the cover is snap-secured therebetween, the two seals remain in continuous sealing contact with the opposing sealing surfaces and neither product, liquid, fluid or gas (steam, for example) will escape. However, under relatively low internal pressure created by elevated product temperatures and steam/gasses emanating therefrom, the innermost first seal will release and vent steam/gas/condensate/liquid to and into the condensation collection chamber. Thereafter, the first seal might close or remain open, depending upon internal pressure of the container. However, under higher elevated pressures, the second seal which is radially outboard of the continuous condensation collection chamber will unseal, at least briefly and temporarily, and vent further gasses (steam) to atmosphere. The latter venting radially beyond the second sealing bead is effected by a plurality of radial venting passages arranged about the periphery of the container and/or cover flanges. Each radial venting passage is defined between a pair of radially outwardly directed ribs with each pair of ribs defining therebetween a venting channel which continuously vents gasses (steam) beyond the outermost second sealing bead to atmosphere. In this manner, the container and cover remain snap-secured together under all normal conditions of packaging, transport and usage, spillage is prevented, and bulging does not occur which assures effective functioning of associated stacking/inter-nesting features of the invention. 
   In further keeping with the invention, the container body and cover include complementary pairs of substantially concentric stacking walls which can be interengaged so that stacked pairs of the containers remain substantially immobile when being manually carried in stacked relationship or when being transported by vehicle as is ofttimes done by way of home delivery from an associated restaurant. Preferably, the stacking walls are defined by a center circular recess which receives a boss and a depending circular bead which is received in a channel of the container body and cover. Because of the double seal self-venting features of the invention earlier described, pressure does not build up in any of the stacked containers, the covers and container bodies thereof will not bulge under pressure, and therefore stacking/inter-nesting is assured. 
   With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a top perspective view of a container constructed in accordance with this invention, and illustrates a cover body and a container body secured to each other along flanges thereof. 
       FIG. 2  is a perspective view of the container of  FIG. 1 , and illustrates the cover and container body disassembled with the latter including a pair of upwardly directed continuous sealing beads and a continuous condensation collection channel therebetween, and outboard of the outboardmost sealing bead a plurality of continuously open radial venting channels each defined by a pair of adjacent radially directed upstanding beads. 
       FIG. 3  is an enlarged cross-sectional view taken generally along line  3 — 3  of  FIG. 1 , and illustrates in further detail the sealing beads of the container body in sealing engagement with sealing surfaces of the cover and stacking/inter-nesting channels and ribs of the cover and the container body, respectively. 
       FIG. 4  is a cross-sectional view substantially identical to  FIG. 3 , and illustrates the cover and container body disassembled and the circumferentially spaced radial ribs between each pair of which is a continuously open relatively wide radial venting channel. 
       FIG. 5  is an enlarged fragmentary radial cross-sectional view taken through the assembled container of  FIGS. 1 and 3 , and illustrates the manner in which a heated product within the container creates steam at elevated temperatures and pressures sufficient to at least temporarily break the innermost continuous seal between the innermost sealing bead and its opposing sealing surface to vent steam/condensate into the continuous condensate collection channel which is radially outwardly sealed under modest internal container elevated pressure by the radially outermost second seal. 
       FIG. 6  is an enlarged fragmentary radial cross-sectional view similar to  FIG. 5 , and illustrates the second seal at least temporarily venting steam/gas to atmosphere under pressure greater than the pressure which opened the first seal of  FIG. 5  and gas/steam being vented to atmosphere through the continuously open radial venting passages. 
       FIG. 7  is an enlarged fragmentary radial cross-sectional view similar to  FIGS. 5 and 6 , and illustrates additional condensate which may form in a second continuous condensation collection channel outboard of the second seal. 
       FIG. 8  is a side elevational view, and illustrates three containers in stacked/inter-nested relationship to each other. 
       FIG. 9  is an enlarged fragmentary radial cross-sectional view through two of the containers of  FIG. 8 , and illustrates the manner in which concentric circular ribs/channels and a central circular projection/recess effects stacking/inter-nesting therebetween. 
       FIG. 10  is a top perspective view of another container, and illustrates a generally polygonal configuration thereof. 
       FIG. 11  is a cross-sectional view taken generally along line  11 — 11  of  FIG. 10 , and illustrates features of the container which are identical to those of  FIGS. 1 through 9 . 
       FIG. 12  is an enlarged fragmentary radial cross-sectional view similar to  FIG. 5 , and illustrates two downwardly projected concentric sealing beads carried by the flange of the cover sealing therebetween a condensation collection channel in a flange of the container body. 
       FIG. 13  is an enlarged radial fragmentary cross-sectional view similar to  FIGS. 5 and 12 , and illustrates two concentric sealing beads projecting respectively upwardly and downwardly from flanges of the respective container body and cover sealing therebetween a condensation collection channel in a flange of the container body. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   A novel container constructed in accordance with this invention is illustrated in  FIGS. 1 through 9  of the drawings and is generally designated by the reference numeral  10 . 
   The container  10  includes a container body  11  and a cover body, cover or lid  12  each constructed of polymeric/copolymeric synthetic plastic material. 
   The container body  11  includes a substantially circular bottom wall  13  terminating in a radius portion  14  which merges with a substantially upstanding cylindrical peripheral wall  15  which in turn merges with a radius portion  16 . The radius portion  16  merges with a flange or annular wall portion  17  which through a radius portion  18  merges with an upstanding peripheral wall  19  radially outwardly of which projects a short annular wall  20  from which depends a downwardly directed peripheral wall or skirt  21  terminating in a terminal edge (unnumbered). The walls  19 ,  20 ,  21  include a plurality of continuous radially extending circumferentially spaced ribs  22  defining between each pair of ribs  22 ,  22  venting means or venting passages  23 . The flange  17  includes a radially outermost continuous upwardly projecting circular sealing bead  25  which is outboard of, spaced from and concentric to a radially innermost continuous upwardly projecting substantially circular sealing bead  26 . The bead  26  is substantially twice the size in height and thickness as the sealing bead  25 . The substantially circular concentric sealing beads  25  and  26  cooperate to define seals between the container body  11  and the cover body or lid  12  in a manner to be described hereinafter. The concentric sealing beads  25 ,  26  also set-off therebetween an innermost substantially continuous condensation collection channel  27 , and an outermost substantially continuous condensation collection channel  28  is defined between the sealing bead  25  and the upstanding peripheral wall  19 . 
   The bottom wall  13  also includes stacking means in the form of a central substantially circular downwardly opening stacking recess  30  and radially outwardly therefrom concentric downwardly projecting radially spaced circular stacking beads or ribs  31 ,  32 . 
   The cover body or lid  12  includes an end panel  33  merging with a radius  34  which in turn merges with a downwardly projecting tapered peripheral wall  35  united by a radius portion  36  to an annular wall or flange  37 . The flange  37  merges with a radius  38  which joins to a peripheral upstanding wall  39  blending with a radially outwardly directed wall  40  which merges with a downwardly directed peripheral wall or skirt  41  having an inwardly directed continuous locking rib or nose  42 . The walls  35 ,  37  include respective inner and outer substantially concentric radially spaced sealing surfaces  46 ,  45  which are in alignment with and seal against the respective sealing beads  26 ,  25  of the container body flange  17 . The sealing surface  45  of the annular wall portion or flange  37  is in the form of a substantially continuous shallow downwardly opening recess. As shown in  FIGS. 3 and 5 , the interlocked relationship between the terminal edge (unnumbered) of the peripheral wall or skirt  21  of the container body  11  and the locking nose  42  of the cover body or lid  12  assures that the concentric seals  25 ,  45 ;  26 ,  46  are maintained in intimate interengaged sealing relationship with each other under “normal” design parameters of the container  10  when packaged with a hot product P, as is readily apparent from  FIG. 3  of the drawings. Thus, when the container  10  is interlocked in its closed and sealed position ( FIG. 3 ), the double seals  25 ,  45 ;  26 ,  46  prevent the leakage of product P and prevent hot contents from cooling, particularly when the container body  11  and cover  12  are constructed from polymeric/copolymeric synthetic plastic material. 
   The seals  25 ,  45  and  26 ,  46  are so constructed and arranged as to assure that both seals will remain in sealing contact under relatively low internal pressures caused by gasses, such as steam S ( FIG. 5 ) emanating from the relatively hot product P. The outermost sealing rib  25  has a relatively radially broad sealing surface which is in sealing engagement with the opposing sealing surface  45  of the flange  37 . However, the seal between the sealing bead  26  and the sealing surface  46  is relatively narrow because it is defined by the relatively small radius (unnumbered) of the radially outermost shoulder (unnumbered) of the sealing rib  26  which contacts the sealing surface  46  of the tapered peripheral wall  35  of the cover  12 . The latter two features effectively define the inner seal  26 ,  46  as being appreciably weaker than the outer seal  25 ,  45  formed by the sealing bead  25  and the sealing surface  45 . The latter difference between the weaker sealing force creating the inner seal  26 ,  46  and the stronger force forming the outer seal  25 ,  45  assures selective venting of the interior of the container  12  when packaged with hot food P, as will be more readily apparent by reference to  FIG. 5 . 
   As was noted earlier, within normal slightly elevated temperatures and pressures in the interior of the closed container  10 , the seals  25 ,  45 ;  26 ,  46  remain sealed ( FIG. 3 ). However, should the hot product P at elevated temperatures/pressures beyond design parameters/ranges cause elevated pressures due to the steam S, such elevated pressures beyond normal low pressure design ranges cause the weaker inboard seal  26 ,  46  to open ( FIG. 5 ) and the steam S vents into and collects as condensate C in the continuous condensation collection channel  27 . The condensate C will not pass radially outwardly beyond the seal  25 ,  45  ( FIG. 5 ) which will not unseal or unseat under lower, though elevated, internal pressures. Thus, the condensate C will be trapped and confined in the condensation collection channel  27  and leakage/spillage is avoided. 
   Should the pressure within the container  11  rise above the sealing pressure parameters of the outer seal  25 ,  45 , the latter unseats and steam/gasses pass beyond the outer seal  25 ,  45  ( FIG. 6 ) and vent to atmosphere through the radial vent passages, vent channels or vent means  23  between the ribs  22 ,  22  ( FIGS. 4 and 7 ). Under certain conditions little, if any, condensate will form and collect in the second condensation chamber  28 , but should the same so form, it will be collected therein as indicated by reference character C′ in  FIG. 7 . Accordingly, the container  10  assures excellent double-sealing characteristics, yet permits selective venting to preclude product leakage/spillage. 
   The end panel  33  of the cover body  12  also includes a central circular upstanding or projecting locating boss or projection  50  ( FIGS. 3 ,  4  and  9 ) and radially outwardly therefrom concentric radially spaced circular upwardly opening generally U-shaped locating channels  51 . The locating boss  50  of the cover  12  ( FIGS. 3 ,  8  and  9 ) of an underlying container  11  is housed within the locating recess  30  of a container body  11  of an overlying container  10  while at the same time locating channels  51 ,  52  of the cover  12  of an underlying cover  12  receive therein the circular locating ribs  31 ,  32  of a container body  11  of an overlying container. The latter cooperative locating or stacking means  30 ,  31 ,  32  and  50 ,  51 ,  52  assures that the containers will remain stacked and inter-nested during transport or shipment, as might be done when carried out of a restaurant and/or delivered therefrom. 
   Another container constructed in accordance with this invention is illustrated in  FIGS. 10 and 11  of the drawings, and like reference numerals have been primed and applied thereto to indicate identical structure corresponding to the structure of the container  10 . Thus, a container  10 ′ of  FIGS. 10 and 11  is identical to the container  10  including a container body  11 ′ and a cover or lid  12 ′, including the cooperative double seals  25 ′,  45 ′;  26 ′,  46 ′ thereof and concentric continuous condensation collection channels  27 ′,  28 ′. The only difference between the containers  10 ,  10 ′ is the configuration thereof, namely, circular versus polygonal. 
   Two additional containers  10 ″,  10 ′″ are illustrated respectively in  FIGS. 12 and 13  and all structure identical to the container  10  has been respectively double and triple primed. The major differences between the containers  10 ,  10 ″ and  10 ′″ are the locations of the sealing beads  25 ″,  26 ″ and  25 ′″,  26 ′″ of the respective containers  10 ″,  10 ′″. The container  10 ″ has the sealing beads  25 ″,  26 ″ projecting downwardly from the flange  37 ″ of the cover  12 ″ and sealing with respective sealing surfaces  45 ″,  46 ″ of the flange  17 ″ of the container body  11 ″ of the container  10 ″. In the case of the container  10 ′″, the sealing beads  25 ′″,  26 ′″ project respectively upwardly and downwardly from the respective flanges  17 ′″,  37 ′″ of the respective container body  11 ′″ and cover  12 ′″. However, in both cases each of the containers  10 ″ and  10 ′″ include inner and outer substantially continuous condensation collection channels  27 ″,  28 ″ and  27 ′″,  28 ′″. The seals  25 ″,  45 ″;  26 ″,  46 ″; and  25 ′″,  45 ′″;  26 ′″,  46 ′″ of the respective containers  10 ″,  10 ′″ function in the manner heretofore described with respect to the seals  25 ,  45 , and  26 ,  46 , respectively, of the container  10  with respect to sealing and selective venting. 
   Although a preferred embodiment of the invention has been specifically illustrated and described herein, it is to be understood that minor variations may be made in the apparatus without departing from the spirit and scope of the invention, as defined by the appended claims.