This invention generally relates to packaging machines and, more particularly, to those machines that wrap and seal sheets of packaging material around loose, elongated products.
It should be appreciated at the outset that packaging products such as spaghetti, straws, carrots, celery, licorice sticks and macaroni is particularly difficult. For example, spaghetti is not only rigid and brittle but also is easily tangled and broken. In addition, because of their elongated shape these products are not easily adapted to packaging in flexible film.
In recent years various machines have been developed for packaging these elongated, semi-rigid products. Generally, these machines wrap the packaging material around the product rather than inserting the product into a preformed container. One such machine is disclosed in U.S. Pat. No. 3,109,502, entitled "Spaghetti Wrapping Machine and Method," issued on Nov. 5, 1963, and its Continuation-in-Part, issued on Jan. 25, 1966, as U.S. Pat. No. 3,203,686. In particular, the machine described in these patents processes weighted amounts of the product in turn, step by step. Sheets of wrapping material are singularly cut and positioned one by one onto buckets mounted on a bucket conveyor. The machine weighs out the product in single lots and deposits each lot in turn into one of the buckets. The complete longitudinal seal for each package is made in two operational steps, i.e. tacking and closure sealing. These steps are performed in turn, one after the other on each package. The end seal is made on each package by arcuately moving fingers and a laterally displaceable heat sealer. The step of end sealing is likewise performed on each package in turn, one at a time, as the packages pass through the machine.
Although this machine and other machines in the prior art operate satisfactorily, there is a need in the packaging industry for new machines that can operate faster and more efficiently. There is a continuing effort in this industry to develop better machines that can package more products in fewer operations and at lower operating costs.