Abstract:
A barrel body with a cross-section surface that approaches the shape of a square with slightly embossed side surfaces and rounded corner areas. The barrel body can be equipped with stiffening elements that run vertically and/or horizontally.

Description:
BACKGROUND OF THE INVENTION 
   The invention relates to a large-volume container made of thermoplastic material. The container can be designed as a tight-sealed barrel or a barrel with a loose lid with a clamping ring. 
   Large-volume containers exhibit a capacity (filling volume) of approximately 100 liters or more and are in their tight-sealed barrel embodiment for storing and transporting liquid contents and in the loose lid embodiment preferably for receiving solid, particle-shaped or pasty contents (e.g. rubble, granulate, powders, pastes, etc.). 
   SUMMARY OF THE INVENTION 
   The object of the present invention is to provide a generic container, in which, through a change in its design, improved use of the floor space on pallets can be achieved, and also through constructive measures a lessening of the tendency to bulge out. 
   This object is attained according to the invention, in that the shape of the body of the barrel exhibits one of sectional area approaching the shape of a square with slightly embossed side surfaces and rounded corner areas. Through this measure, better use of the floor space on pallets is achieved. The unused volume of space in between stacked barrels according to the invention is considerably reduced in comparison to traditional round barrels and use of previously unused space volume for freight (e.g. with ISO containers) is increased. 
   In the design of the invention it is provided that the body of the barrel is equipped with vertically and/or horizontally running stiffening elements, the denting of the flattened side walls is considerably reduced. 
   The stiffening elements can be designed as open U-shaped or V-shaped rib-like forms that run toward the inside and/or to the outside. 
   Advantageously, the horizontally running stiffening elements can be designed as molded and thickened mold hoops, for a stable design of the barrel body. Advantageously, the mold hoops are molded during the blow molding of the barrel body through a stamping-out process from the walls of the barrel body. So that the mold hoops exhibit approximately the same exterior diameter as the remaining barrel wall, they can be arranged in an approximately V-shaped mold that rounds around toward and is open toward the outside. 
   The plastic barrel according to the invention is further distinguished by the following features and advantages: 
   In an embodiment as a tightly sealed barrel, a central bung piece is located, if necessary, in a die-sunk bung mold, on the upper barrel floor, so that it is protected. In another embodiment, two lateral bung pieces are located in appropriately die-sunk bung house on the upper barrel floor. On the upper circumference of the barrel body, an L-ring is designed as a handling ring. The stiffening elements are U-shaped or V-shaped rib-like molded parts that are open toward the inside and/or toward the outside. The horizontally running stiffening elements are designed as thickened mold hoops molded from the walls of the barrel. The mold hoops are molded from the wall of the barrel body by a stamping-out process during the blow molding of the barrel body. The mold hoops that have been stamped can be arranged in such a way that they run around the circumference in a somewhat V-shaped form, open toward the outside. When only one stiffening ring running around the circumference is provided, then it is located in an area of the barrel body from the middle to the lower third of the barrel body, preferably measured at a height of approximately 43% from the floor of the barrel. 
   Thus the following advantages are achieved: The stiffness and resistance to denting of the flattened areas of the walls of the barrel and the ease of loading the containers in stacks is overall enhanced. 

   
     BRIEF DESCRIPTION OF THE DESCRIPTION 
     The invention is further explained and described below in the drawings of the embodiments that are presented. The following is shown: 
       FIG. 1  is a top view of a container according to the invention; 
       FIG. 2  is a side view of another container according to the invention, with a partial sectional view in the upper and lower area; 
       FIG. 3  is a sectional view through the barrel body of a container according to the invention with a circular comparison; and 
       FIG. 4  is a side view of another container according to the invention with a partial section view in the upper and lower area. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Reference number  10  shows a large-volume blow molded bung barrel made of thermoplastic material in  FIG. 1  with a capacity of 250 liters, which is equipped on the upper wall of the container with L-ring  12  that runs around the circumference as a handling hoop. In the top of the barrel are located two side bungs  14  in die-sunk bung molds  16 . In this top view, the square-shaped design becomes clear, namely that the barrel bottom exhibits a sectional surface that approximates the shape of a square with side surfaces that are slightly embossed and rounded corner areas. 
   As seen in the top view of  FIG. 1 , the barrel body has four substantially identically shaped, outwardly bowed or convex side surfaces  24   a ,  24   b ,  24   c  and  24   d , each side surface being connected to two adjacent side surfaces at rounded corners  26   a ,  26   b ,  26   c  and  26   d . The convex side surfaces and the rounded corners impart an approximately square-shaped cross-section to the barrel body which allows better use of floor space on a pallet. 
     FIG. 2  shows an embodiment with a bung  14  centrally located in a bung mold  16 . In the left half the picture, the bung barrel  10  is equipped with a foot hoop  18  that runs around the circumference (a hoop that allows it be rolled over the floor), while in the right-half of the picture, another embodiment without a foot hoop is shown. 
     FIG. 3  shows a cross-section through the wall of a barrel body according to the invention, which can be designed as a barrel with a loose lid. In comparison to that, a circle with the same circumferential length is superimposed over it. This circle is intended to show the usual bulging-out tendency of a barrel filled with content. Thus the barrel has a tendency to bulge out on the flat areas of the wall and to pull inward in the areas of the corners, and thereby to assume a circular shape as the shape with the least tension. To work against this disadvantageous tendency, the barrel body, as shown at the left side in  FIG. 4 , is equipped with a mold hoop  22  that runs around its circumference. This mold hoop  22  is measured at a height of about 43% from the floor, is inserted in molded piece  20  in such a way that the circumference of the mold hoop and the rest of the barrel body are approximately the same. The mold hoop can stick out slightly, so that barrels standing next to one another touch one another with their mold hoop. The right side of  FIG. 4  shows a molded piece as a stiffening element. Here the molded piece is open toward to outside of the barrel body.