The invention relates to a lid seal for wide-mouthed barrels of synthetic resin, having an outer rim encompassing the neck of the blow-molded plastic barrel and with an inner rim dipping into the barrel neck and projecting beyond the lid bottom below the barrel opening, and having a gasket inserted or foamed into the annular space between the outer lid rim and the inner lid rim, this gasket being urged by a seal against the opening rim of the barrel neck, the seal clamping in place a flange or, respectively, flange sections, molded at the bottom to the outer lid rim, against a solid border radially outwardly projecting from the barrel wall at a spacing below the barrel opening.
In such a wide-mouthed barrel, known from DE 25 44 491 C2, the lid is sealed by means of a metal clamping ring exhibiting a trapezoidal profile, this ring being placed around the lid flange and the barrel border. This lid closure harbors the danger that upon impact of the lid rim on the ground during a fall of the barrel from a height, or during the tilting over of the barrel, the clamping ring is deformed and the lid loses its sealing.
The invention is based on the object of developing a barrel lid seal improved with respect to its functional safety.
The lid seal according to this invention is distinguished by the following advantages:
The two clamping rings of the lid seal are elastically deformable so that, upon exposure to external force by impact or shock upon falling or tipping over of the barrel, the danger of damage to the seal and thus an ensuing leakage of the barrel lid is prevented. The lid seal can be mounted on the barrel lid quickly and simply with an appropriate device. On account of the two clamping rings, the barrel flange and the lid flange are reinforced so that the stacking load on a barrel equipped with the novel seal can be increased. By providing a plastic barrel with the lid seal of plastic, the barrel can be readily subjected to a recycling process on account of the use of a single manufacturing material. Finally, the lid of a barrel prepared for the novel sealing system can, if needed, be closed off by a conventional clamping ring.
The invention is described in greater detail below with reference to various embodiments of lid seals for wide-mouthed barrels illustrated in the drawings wherein:
FIG. 1 shows a fragmentary enlarged sectional view of a wide-mouthed barrel lid provided with a first embodiment of the novel seal,
FIG. 2 is a top view of the complete lid according to FIG. 1, and
FIGS. 3 and 4 show illustrations of wide-mouthed barrel lids corresponding to FIG. 1, with two further embodiments of the lid seal.
The lid 1, injection-molded, for example, of polyethylene, which can be attached by means of the various seals illustrated in FIGS. 1 through 4 to a wide-mouthed barrel 2 blow-molded from a synthetic resin, comprises an outer rim 4 encompassing the barrel neck 3 and an inner rim 5 dipping into the barrel neck 3, projecting beyond the lid bottom 6 below the barrel opening. A gasket 8 is inserted or foamed in place in the annular space 7 between the outer lid rim 4 and the inner lid rim 5.
The lid seal according to FIGS. 1 and 2 utilizes a solid clamping ring 9 of plastic, this ring being in contact with the underside of a solid flange 10 which latter projects radially outwardly at a spacing below the barrel opening, away from the barrel wall. The arrangement further includes a counter ring 11, likewise made of a synthetic resin, resting on a flange 12 molded at the bottom to the outer lid rim 4. Locking sleeves 13, 14 are molded on the clamping rings 9, 11, distributed about the circumference thereof, and engage in corresponding bores 15, 16 in the barrel flange 10 and in the lid flange 12. The clamping rings 9, 11 and the locking sleeves 13, 14 molded thereon have conical through bores 17, 18. For closing the lid 1, placed on the wide-mouthed barrel 2, clamping bolts 19 of plastic or metal are urged from above by means of a pressing tool into the conical bores 18, 17, aligned with each other, of the two clamping rings 11, 9; and during this operation the ring 9, in contact with the barrel flange 10, is supported by means of an appropriate device. On account of the clamping force exerted by the clamping bolts 19, the gasket 8 is pressed against the opening rim of the barrel neck 3.
In the lid closure according to FIG. 3, locking sleeves 20 are molded on the clamping ring 9, in contact with the barrel flange 10, these sleeves being distributed about the ring circumference and engaging in corresponding bores 15, 16 in the barrel flange 10 and in the lid flange 12, aligned with respect to each other in congruent fashion. The counter ring 11, placed from above onto the lid flange 12, has clamping bolts 21 formed integrally with this ring, which are inserted into the locking sleeves 20 of the ring 9; these bolts are split and snap behind the ring 9 with barbs 22 formed at the resilient ends provided by their split construction.
The lid seal according to FIG. 4 differs from the seal of FIG. 3 by the feature that the clamping bolts 21 formed on the counter ring 11 are locked together with the clamping ring 9 by means of claw elements 23 arranged at the ends, so that opening of the lid closure is possible only by destruction of the clamping rings 9, 11, and this seal thus constitutes a security seal for the barrel.
The clamping rings 9, 11 are produced as plastic injection-molded parts.