Gasketless Closure For Open-Top Pails

Abstract

A molded plastic closure is configured to provide a plug fit with the top rim of an open top container having an outwardly protruding rim flange. A two-part seal preventing leakage of fluid from the container is provided by means of a ridge structure on the inner wall of the inverted U-shaped channel of the closure peripheral structure as well as a flexible sealing wiper appendage which is formed integrally with the top of the inverted U-shaped structure and which deformingly contacts the top surface of the container rim when the rim is essentially fully inserted into the U-shaped channel. The wiper appendage is formed to angle toward the inner channel wall in the undeflected condition.

Description

FIELD OF THE INVENTION[0001]This invention relates to closures; i.e., “lids,” for open-top pails and, more particularly, to a plug fit closure that provides an effective seal between the closure and the pail without the use of a conventional gasket.BACKGROUND[0002]Molded plastic closures for open-top pails are in wide spread use and are available from numerous manufacturers including the Letica Corporation of Rochester, Mich. The pails, also called “containers,” and closures are generally made from high density polyethylene, hereinafter “HDPE,” and are injection molded in a range of capacities from about one to six gallons and may or may not have pouring spouts and bails for carrying. The closures snap or “lock” firmly on the pails and may have various means such as tear bands on an outer skirt to aid in removal from the pail.[0003]Where such pails are used to carry perishable goods or fluids, it is common to design the closure to provide a “plug fit” wherein the pail rim extends in...

AI Technical Summary

Benefits of technology

[0011]As a result of the design of the closure herein described and the cooperation between the closure and the pail, a firm and reliable gasketless seal that can withstand rough handling without leakage is accomplished in a cost-efficient fashion. By virtue of the seal, air is prevented from entering container during storage to spoil or otherwise adversely affect perishable content, and leakage of fluids from the container in the event of tip overs, drops, and other handling events is substantially prevented.

Problems solved by technology

The gasket itself adds to the cost of the product and the placement of the gasket into the channel is a secondary operation that adds still more cost and complexity to the manufacturing process.

This presents a competitive disadvantage; moreover, recycling of the closure becomes more complex because of the different materials used to make the closure and the gasket.

Again, this puts pressure on the design, manufacture, and maintenance of the tooling used to injection mold the HDPE lid and pail.

Further, the seals can lose effectiveness due to age and / or damage to the pail rim or the closure channel through ordinary handling.

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