Today's modern society has the need to transport and contain liquid and solid materials in versatile containers. For various purposes, a variety of containers have been developed ranging in size from ocean going tankers to small cans and jars. One container that has been available for many years in a number of forms is a bucket.
Buckets are used for a number of applications, most of which involve short term storage of liquids or other materials. Examples of typical uses would include carrying water from a faucet to a remote location and carrying soil from one location to another. Both these uses involve short term placement of relatively stable materials in the bucket.
If less stable materials are placed in a bucket for longer periods, a simple bucket often will not suffice. For example, consider the storage of a petro-chemical solvent having a high rate of evaporation. This liquid, if left exposed to the open air, is soon depleted through evaporation. Many solids are subject to dispersion to the environment as well. One example is common fertilizer which loses effectiveness over time if left exposed to the open air. Still further, loss of fluids and solids can also occur during transportation. More specifically, liquids, because of their fluid nature, tend to slosh around when the container holding them is moved. If the sloshing is severe enough, the liquids can spill over the edge of the container. Even solids may be spilled if the container is tipped severely enough.
Typically, to avoid these problems a cover is fastened to the container. Container covers come in primarily two types, namely single use and reusable covers. Single use covers are those types which can be applied and removed only once whereas reusable covers can be used more than once. To reduce costs and to minimize waste, reusable covers may be preferred. In fact, many manufacturers design their containers to include reusable closures. Unfortunately, other containers are closureless and cannot accept available reusable lids.
A number of container covers have been developed in the past. One example is found in U.S. Pat. No. 4,416,197 issued for an invention entitled "Waste Material Compactor Apparatus" which describes a two-part cover. This reusable cover includes a lip member and a cover member which closes an opening in the lip member. On the other hand, this cover does not provide an airtight seal and the cover member merely lays on the lip member, but is not attached.
U.S. Pat. No. 4,874,103 for an invention entitled "Receptacle for Receiving Infectious Waste" describes another cover attachable to a container. This cover includes an opening with a door hinging inward. The door allows placement of materials into the container, but prevents future access to the materials within the container.
Other covers have been developed which are reclosable covers for use with buckets, but because of their designs, have openings which are relatively small. One example is disclosed in U.S. Pat. No. 4,288,000 entitled "Child-Resistant Lid" issued for a reusable cover intended to be child resistant. To accomplish this, the removable portion of the lid must be compressed around its circumference prior to unthreading. The design of the locking member requires that the outer diameter of the removable portion be small enough to be gripped by the hand of an adult. For this reason, the opening to the container will be slightly smaller than an adults hand. While this is sufficient for containing smaller items in the bucket, it substantially hinders access to the bucket's contents and is incompatible with items larger than the opening. Similar small opening closures are disclosed in U.S. Pat. No. 4,779,754 and U.S. Pat. No. 4,949,865.
These prior closures suffer from a number of drawbacks, namely they are not air-tight, are not reclosable or have an opening which significantly reduces the opening of the container.
In light of the above, it is an object of the present invention to provide a multiple use closure for containers. Another object of the present invention is to provide a closure system which can convert a container not previously having a closure to one which accepts a reusable closure. Further, it is an object of the present invention to provide an adaptable closure which is removable and allows ready access to the contents of the container. Still further, it is an object of the present invention to provide a closure which provides an airtight seal for containers not previously including a sealing means. Yet another object of the present invention is to provide a resealable closure which is useable for sealing liquids and solids in a container. And still another object of the present invention is to provide a reusable closure for containers which has an opening nearly as large as the opening of the container itself. Another object of the present invention is to provide a closure which is relatively easy to manufacture and which is comparatively economical.