Containers formed of corrugated paperboard are used in many different applications, such as, for example, to store and ship agricultural produce. These containers typically have a bottom wall, opposite side walls, and opposite end walls, and are formed from a blank of corrugated paperboard scored with score lines or cut lines. The paperboard blank is folded along the score lines or cut lines to form a container, and may be folded into the container by an automated machine, or the consumer may erect them manually. A removable top may be placed on the container, although it is not required.
Containers made of corrugated paperboard usually are recyclable, and generally are less expensive than containers made of wood, metal or plastic, but they must have sufficient strength to withstand the stresses imposed on them by vertical stacking, and the wear and tear of shipping and handling, particularly to avoid damage to the contained product. Thus, paperboard containers are sometimes reinforced with additional structures. Other reinforcement structures may take the form of beams or ridges that are integrally formed in the side or bottom walls, or in an interior lining of the container. These supports, however, limit the interior space of the container and require excessive amounts of additional material.
Other reinforced containers have beams or other rigid structures that extend over an upper portion or top of the container. This type of reinforcement is more commonly used in containers that are especially short and wide, and/or have a removable cover, wherein the removable cover bears an undue amount of stress. However, these types of reinforcements are often bonded to the cover and do not come in significant contact with the side walls, lessening the strength of the reinforcement system.
Further, agricultural produce normally is packed in shipping containers in a cool damp environment, and tends to pool in the bottom of the container, causing the container bottom to sag. This sag tends to transfer from one container to another when the containers are stacked on top of one another for storage and handling. Top reinforcements tend to obscure or impair the visibility of the product contained in the container unless they are removable.
Therefore, it is an object of this invention to provide a paperboard container with a reinforcement structure that at least partially supports the product held in the container to prevent sagging of the container bottom, and that does not unduly restrict the interior volume of the container, or impair the visibility of the product.