This invention relates to a drum cover and, more particularly, to a cover with center support for a mixer or the like.
In one form of conventional shipping and storage container, a drum comprises a tubular container having an open end with a cylindrical connecting bead at the open end. The connecting bead may be provided by a metal connecting ring rolled onto the side wall or a plastic connecting ring molded directly to or otherwise adhered to the side wall. Alternatively, the side wall may be of molded plastic construction with an integral connecting bead.
The conventional drum includes a removable cover for closing the open end of the tubular side wall. A typical cover includes a central circular wall with a peripheral connecting flange receivable on the connecting bead so that the circular wall closes the open end of the container. A locking band secures the cover on the drum.
Occasionally a drum, such as a conventional 55 gallon drum, is used to carry liquid which must be mixed. An example is a liquid used for foam insulation. Such a drum could be formed of fiber, plastic, steel or composite construction. Typically, the cover is made from steel having a bung opening supporting a mixer including a motor that drives a mixing shaft and blade. The steel cover provides necessary strength to support weight of the mixer. Currently, a plastic cover is also used in such an application fitted with top and bottom steel flanges and a steel threaded adaptor to allow attachment of the mixer to the cover. The use of metal covers or plastic cover with metal flanges increases the cost and weight of the shipping container.
The present invention is directed to solving one or more of the problems discussed above in a novel and simple manner.
In accordance with the invention, there is provided a cover for use with a tubular container having a center support structure.
There is disclosed in accordance with one aspect of the invention a unitary cover for use with a tubular container having an open end with a cylindrical connecting bead at the open end. The unitary cover comprises a central circular wall. An annular flange is at a periphery of the central circular wall comprising a downwardly opening U-shaped channel receivable on the cylindrical connecting bead. A bung opening is provided through the central circular wall. A rib network depends downwardly from the central circular wall surrounding the bung opening.
It is a feature of the invention that the central circular wall is generally planar and has a raised support area surrounding the bung opening. The rib network extends radially beyond the raised support area.
It is another feature of the invention that the rib network comprises a threaded collar defining the bung opening. An annular rib is coaxial with the threaded collar. A plurality of radial ribs extend between the annular rib and the threaded collar. The central circular wall may be generally planar and has a raised support area surrounding the bung opening with a diameter of the support area being less than the diameter of the annular rib. The bottom edges of the ribs are coplanar.
It is a further feature of the invention to include a concentric ring extending downwardly from the annular flange and connecting the annular flange to the central circular wall. The radial ribs may extend from the threaded collar to the concentric ring. The bottom edges of the ribs and the concentric ring are coplanar.
It is another feature of the invention that the cover is of molded plastic construction.
There is disclosed in accordance with a further aspect of the invention a unitary plastic cover for use with a tubular container having an open end with a cylindrical connecting bead at the open end. The unitary cover comprises a central circular wall. An annular flange is at a periphery of the central circular wall comprising a downwardly opening U-shaped channel receivable on the cylindrical connecting bead. A bung opening is provided through the central circular wall. A rib network depends downwardly from the central circular wall surrounding the bung opening.
It is another feature of the invention that the central circular wall has a greater wall thickness than the rib network.
Further features and advantages of the invention will be readily apparent from the specification and from the drawings.
In the illustrated embodiment of the invention, as disclosed in
In the illustrated embodiment of the invention, the drum 10 comprises a cylindrical, blow-molded plastic drum. The drum may have a capacity in the range of about of 35 to 55 U.S. gallons and the connecting bead 20 has a diameter in the range of about 18″ to 23″. As is apparent, the dimensions of the drum 12 may vary. The present invention is directed particularly to the cover 22 which can be used with drums of other construction, such as metal, fiberboard, or composite construction, as will be apparent. Particularly, the cover 22 includes integrally formed structure enabling the cover to support a mixer 26. The mixer 26 may include, for example, a motor 28 having a cylindrical sleeve 30 connected to an adaptor 32. The sleeve 30 receives a shaft 33 for driving a blade 34. Particularly, the adaptor 32 is threaded to a center bung opening 36, see
Referring to
The circular wall 40 has a peripheral edge 52. A concentric ring 54 is radially outwardly of the peripheral edge 52 and extends above and below the circular wall 40, see
As described, when the cover 22 is mounted to the drum 14, the connecting bead 20 is received in the channel 58, as is conventional. The locking band 24 sandwiches the peripheral flange 56, gasket and connecting bead 20 to retain the cover 22 on the drum 10 in a conventional manner.
In accordance with the invention, the cover 22 includes support structure 60 providing center support for the mixer 26. The structure 60 comprises a raised annular support area 62 surrounding the center bung opening 36 and a rib network 64 depending downwardly from the central circular wall 40 surrounding the bung opening 36.
The bung opening 36 is formed by a threaded collar 66 having a diameter of about 2″. The annular support area 62 may be on the order of about 4″ in diameter. The annular support area 62 includes a tapered edge 68 connecting with the flat upper surface 42.
The rib network 64 comprises the threaded collar 66 and an annular rib 70 coaxial with the collar 66. The annular rib 66 has a diameter greater than the diameter of the annular support area 62, as is seen in
The radial ribs 72 and 72′ increase in height between the annular rib 70 and the threaded collar 66 owing to the higher elevation of the annular support 62, as is apparent in
In accordance with the invention, the cover 22 is provided with the central circular wall 40 and annular support area 62 having uniform wall thickness of about 150 mil. The rib network 64 is formed with the ribs having common thickness on the order of 110 to 120 mil. As such, the ribs are of lesser thickness than the wall. The height of the ribs is about 1″ except in areas below the raised central support 62. The drum cover 22 is formed such as by injection molding of plastic and results in a weight on the order of about 3 lbs. This compares to a metal cover which weighs about 7 lbs. The raised annular support area 62 along with the rib network 64 adds strength at the central point for supporting the mixer 26.
While the support structure 60 is illustrated in the center of the cover 22, the support structure could be provided off center, as is apparent.
Thus, in accordance with the invention, there is provided a unitary cover including support structure for supporting a mixer or the like.