Abstract:
A combination molded plastic bucket and lid includes a bucket having a circumferential groove along the bottom edge of the bucket compatible with a circumferential rim of the lid and designed to fit within the groove. In this manner multiple buckets may be stacked one upon the other without slipping or sliding with respect to one another.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    In a principal aspect the present invention relates to a molded plastic bucket and lid construction wherein, the bucket and lid are configured in a manner which promotes effective stacking of buckets with lids for shipment or storage.  
           [0002]    Various types of molded plastic buckets or containers are known. For example, molded plastic buckets are disclosed in the following patents of John W. von Holdt Sr.: U.S. Pat. Nos. 4,275,948; 4,574,974; 4,512,494; 4,512,493; 4,452,383; 4,380,305; 4,308,970; and ,210,258. Buckets or containers disclosed in the aforesaid patents are useful for storage of powder or liquid materials including, paint, solvents and chemicals. The disclosed molded plastic buckets are typically manufactured using injection molding techniques by an entity skilled in the practice of such techniques. The containers or buckets and compatible molded plastic lids are then shipped to entities, which desire to fill the containers with a product. Filled containers with attached lids are then shipped to wholesale distributors and otherwise dispersed throughout various channels of commerce. Typically, the lidded containers are shipped in large or bulk quantities on shipping pallets. When shipped in this manner it is necessary to stack the buckets or containers one upon the other to provide an efficient and economically sized package for transport by pallet.  
           [0003]    An objective associated with such stacking is to provide a means by which the stacked buckets with lids will remain appropriately oriented and stacked one upon the other during shipment. Thus, there has developed a need to provide means by which filled, stacked buckets may be appropriately positioned one on top of another in a stacked condition without tilting, falling or slipping. Further, it is desirable to have such capability for purposes of display of stacked buckets on display counters in retail stores and retail outlets. Thus, the idea of stacking multiple containers or buckets one upon the other for purposes of transportation, shipment or display is a characteristic feature or objective that is much desired.  
         SUMMARY OF THE INVENTION  
         [0004]    Briefly, the present invention comprises a molded plastic bucket or container and a compatible lid combination wherein, the bucket and lid are configured in a manner which facilitates the stacking of buckets with lids one upon the other. More particularly the bottom of each bucket is formed with a circumferential or annular groove about its outer periphery. The lid for the container or bucket is provided with a circumferential or annular rim configured and dimensioned in a manner to be received and nested within the groove of the bottom of a bucket stacked thereon. Various dimensional and structural details are associated with the shape, location and dimensions of groove in the bottom of the bucket and the peripheral rim of the lid, which is placed on the top of the bucket, to enable or ensure that stacked buckets will not slip and that the buckets can be effectively and efficiently displayed or stored or packed for shipping.  
           [0005]    Thus, it is an object of the invention to provide an improved combination molded plastic bucket and lid construction which is especially useful for stacking of filled buckets.  
           [0006]    It is a further object of the invention to provide an improved plastic bucket and lid combination useful for stacking of buckets one upon the other without intervening layers of material to ensure that the stack of containers or buckets will remain in an interlocked relationship for shipment or display.  
           [0007]    A further object of the invention is to provide an economical and efficient design useful for the stacking of a bucket upon a lid of a container of a vertically adjacent bucket and lid combination.  
           [0008]    These and other objects, advantages and features of the invention will be set forth in the detailed description which follows.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0009]    In the detailed description, which follows, reference will be made to the drawing comprised of the following figures:  
         [0010]    [0010]FIG. 1 is a perspective view of a combination bucket and lid made in accord with the invention;  
         [0011]    [0011]FIG. 2 is a cross sectional view of the bucket of FIG. 1 along the vertical section through the middle axis of the bucket;  
         [0012]    [0012]FIG. 3 is an enlarged cross sectional view of the combination lid and bucket with a second bucket stacked upon the lid of the first bucket;  
         [0013]    [0013]FIG. 4 is an enlarged cross sectional view of the stacking arrangement of a bucket upon a lid associated with a bucket as depicted in FIG. 3; and  
         [0014]    [0014]FIG. 5 is a cross sectional view of two lids stacked one upon the other.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0015]    Referring first to FIG. 1, a lid  10  is a generally planar, molded plastic member having a circular shape and generally symmetrical about a vertical middle axis  12 . The lid  10  is formed to be compatible with, fit upon and remain engaged with a top rim  14  of a bucket  16 . The bucket  16  is likewise symmetrical about the vertical middle axis  12 .  
         [0016]    Bucket  16  is formed by injection molding of a polymeric material and includes a generally cylindrical, circular cross section sidewall  20  and a generally circular bottom wall  18 . The bucket  16  further includes an open top  15  with a circular peripheral rim  14  that is compatible with the lid  10 . The particular configuration or attachment design or element incorporate in rim  14  and lid  10  for affixing the lid  10  to rim  14  is not a limiting feature of the invention. However, the rim  14  typically includes an outwardly extending rib  19  cooperative with inwardly extending tab or flange  17  of lid  10  so that the lid  10  is removably affixed to the bucket rim  14 .  
         [0017]    The subject matter of the invention relates, in part, to the particular configuration of bottom wall  18  of the bucket  16 . More specifically, the bottom wall  18  includes an outer or first circumferential lip  24  radially spaced a first radial distance R 1  from the middle line axis  12 . A second, outer circumferential radial lip  22  is spaced a distance R 2  from the middle line axis  12  and, in combination with the first rib  22 , defines a circumferential or annular groove  26 . The outer or first rib  24  extends slightly radially beyond the outside face  28  of the bucket sidewall  20  adjacent bottom wall  18 . The ribs  22  and  24  thus define an annular groove or channel  26  in the bottom wall  18 . The first and second ribs  22  and  24  are preferably continuous annular rings, but may be intermittent or segmented. A second annular groove  30  is defined in wall  18  inwardly from the second rib  22 . The second annular groove  30  contours the uniform thickness, bottom wall  18  thereby providing a reinforcing feature for the bottom wall  18 . Central circular recessed section or panel section  32  of the bottom wall  18  provides a further reinforcing function for the bottom wall  18 .  
         [0018]    Lid  10  includes a circumferential, annular rib  44  projecting upwardly. Rib  44  is configured to be compatible with the groove  26  in bottom wall  18  of the bucket  16  as defined by the two spaced ribs  22  and  24 . Thus, as depicted in FIGS. 3 and 4, a bucket  16  may be stacked upon the lid  10 . That is, the groove  26 , formed by the spaced ribs  22  and  24 , is dimensioned so that it will receive the rib  44  associated with the lid  10 . The cross sectional shape of rib  44  is designed and dimensioned to fit congruently into groove  26 . Lid  10  is also designed so that the remainder of outside surface of lid  10  will not prevent engagement of rib  44  into groove  26 .  
         [0019]    The bottom wall  18  of bucket  16  may be designed so that annular sections  35  and  37  may rest against opposed annular sections  39  and  41  of the lid  10 . Thus, an inner annular rib  39  may project from the top surface of lid  10  to support the bottom section  35  of bottom panel  18  of bucket  16  by fitting against bottom wall  18 . Preferably only the tongue or rib  44  of lid  10  will fully rest or engage the bucket groove  26 .  
         [0020]    Functionally, the inside face of the first rib  24  fits against the outside surface or edge of lid rib  44  thereby maintaining a bucket  16  placed on a lid  10  and preventing lateral or side to side movement of the bucket  16  relative to lid  10 .  
         [0021]    By maintaining the outside rib  24  maximum radius within the maximum radial dimension of the bucket  16  and attached lid  10 , (hereinafter the maximum assembly radius) the stacking arrangement of multiple vertically stacked buckets  16  falls within a vertical cylinder defined by the maximum assembly radius. This insures an efficient packaging of vertical stacks of buckets with lids on a pallet.  
         [0022]    Variations of the construction may be effected with out departing from the spirit and scope of the invention. For example, the configuration of the bucket  16  and lid  10  need not be cylindrical. Rectangular container shapes may incorporate the stacking feature of the invention. Also, the first rib  24 , as well as the outer edge of lid rib  44 , may be discontinuous so long as there is maintained opposed surfaces of lid rib  44  and first bucket rib  24 . Therefore the invention is limited only by the following claims and equivalents.