Valved Canning Lid

With no new art having made an impression in the market place, conventional sealer lids generally used by the home canner today are considered expendable. The most commonly used lid is worked up and down by cooking pressures escaping along the jar lip during the canning process. The sealer gasket on this type of lid is usually rendered lifeless after one application, and the usefulness of the lid is severely limited. The possibility also exists that some of the cooking materials will boil out under the sealer of the lifted lid. A later danger can then develop that a bacterial path having been formed, the food in the sealed jar could become contaminated. Also, these sealer lids usually require prying to remove them from the jar lip. Prying can be damaging to the lid making its safe use more than once doubtful. From a manufacturing standpoint, the design of conventionally used sealer lids considerably limits the choice of material applicable.

In the prior art, attempts to improve upon canning jar sealer lids do not appear to have challenged the superiority of the original single snap lids presently in demand by home canners. A patent issued to John J. Williams, U.S. Pat. No. 1,808,702, dated June 2, 1931, shows a relief valve and sectional lid approach. His cap with a single aperture in the top and a padded sealer disc has the disadvantage of small apertures facing down towards the processing food and the danger of the food entering these apertures. The double sealer rings as required in this lid are inconvenient, and the inventor provides no method to manually unseal his relief valve other than unscrewing the cap.

These small downward facing apertures are again present in the sealer lid described in U.S. Pat. No. 1,576,763, issued to H. Ingram on Mar. 16, 1926. No means is supplied for releasing vacuum to protect the cap from damage when twisting it off the jar.

The present invention is designed to overcome limitations in currently used sealer lids. As illustrated in the drawings and described in more detail hereinafter, the valved lid comprising this invention eliminates the need for sealer lid surface movement either to release internal jar pressure or to vacuum seal the lid to the jar lip. And as the thickness of the material used in the main sealer section is not critical, the possibilities for usable materials in the manufacture of the present invention is greatly enlarged.

Therefore, this invention is a canning jar sealer lid provided with a pressure relief valve in the surface of the lid. The valve is preset to operate as needed so the lid and sealer gasket at the lip of the jar are not required to lift for releasing internal jar pressure during the canning process.

A sectional embodiment of the present invention, the valved canning lid, is provided with an external sealer or cap and an internal sealer or disc hereinafter referred to as cap and disc. A sealer gasket extends around the circumference of the disc on the under surface of a size and arrangement to fit the lip of a conventional canning jar. The cap fits snuggly over the disc sealing off an aperture in the center of the disc. On the upper surface of the disc and around the aperture, there is a rubberized gasket. Directly above the rubberized gasket, there is a ring of slits in the cap. When the cap and the disc are fitted together, the gasket around the aperture in the disc seals off the slits in the cap. Acting conjointly, the slits in the cap and the gasketed aperture in the disc operate as a relief valve. Pressure from within a jar pushing against the under surface of the cap through the aperture in the disc can force the cap slits away from the disc gasket and release the internal jar pressure. When a jar is vacuum sealed, the center section of the cap is sucked down tightly against the disc aperture gasket shutting off the cap slits completely. An external means is supplied for opening the slits manually to unseal a vacuum sealed sectional lid. The two sections of this lid are also held together by vacuum. A slight protrusion of the circumference disc gasket contacts the inner surface of the cap retainer band or rim. This contact causes a seal which creates some vacuum between the interfaced surfaces of the cap and disc, holding the two sections firmly together. For cleaning, they can be separated by lightly pressing on the cap or by warming.

In a single surface embodiment of this invention, a pressure relief valve seats in an aperture centered in and completely through the sealer lid surface. The valve operates independently of sealer lid movement eliminating frictional wear on both the sealer lid and the sealer gasket. The valve acts as both a relief valve and a vacuum sealer. A means for opening the valve to release a vacuum sealed lid is provided making the lid easy to remove without the necessity of prying. Spring tension applied to the lower shaft of the valve by a especially designed star spring holds the valve shut so the lid can be used as a cap for an opened jar as needed.

Both embodiments of this invention, the sectional lid and the single-thickness lid, are designed to be used either as sealer lids only held in place by separate screw bands or other holders or as complete caps with screw bands or other holders permanently affixed.