Flexible slit valve

Abstract

A dispensing valve is provided for being sealingly disposed with respect to, and dispensing a product from, a discharge opening of a container. The preferred form of the valve includes a generally annular marginal portion adapted to be sealingly engaged when the valve is sealingly disposed with respect to the container discharge opening. The valve also includes a central head portion extending from the marginal portion. The head portion has an exterior side with a generally concave shape when viewed from outside the container and has an interior side with (1) a planar central area, and (2) a generally curved, radially outer portion which tapers toward the planar central area such that the exterior and interior sides converge toward the planar central area to provide a tapered construction with reduced thickness. The head portion includes a normally closed orifice defined by a plurality of slits that extend (1) transversely through the head portion from the exterior side to the interior side, and (2) laterally from a common origin whereby flaps are defined by the slits with each slit terminating in an outer end which is located laterally beyond the planar central area. The orifice opens by outward displacement of the flaps when the pressure in the interior of the container exceeds the pressure on the exterior of the valve by a predetermined amount. The orifice remains open even when the pressure on the interior of the container does not exceed the pressure on the exterior of the valve.

What is claimed is:  
     
       1. A dispensing valve for being sealingly disposed with respect to, and dispensing a product from, a discharge opening of a container, said valve comprising: 
       a marginal portion adapted to be sealingly engaged when said valve is sealingly disposed with respect to the container discharge opening;  
       a head portion that (1) is laterally inwardly of said marginal portion, (2) has an exterior side for interfacing with ambient environment, and (3) has an interior side for interfacing with the product; said head portion having a laterally outwardly flared crown shape defined, at least in part, by a peripheral surface which tapers laterally inwardly to prevent nesting with another, identical valve during handling; said head portion exterior side having a laterally outer portion with an arcuate side elevational shape defined by a first radius; said head portion interior side having a planar central area and a laterally outer portion with an arcuate side elevational shape defined by a second radius which is greater than said first radius such that said outer portions of said exterior and interior sides converge toward said planar central area of said head portion to provide a tapered construction with reduced thickness; said head portion interior side having a periphery defined by a circular, peripheral edge; said head portion including a normally closed orifice defined by a plurality of slits that extend (1) transversely through said head portion from said exterior side to said interior side, and (2) laterally from a common origin whereby flaps are defined by said slits with each slit terminating in an outer end which is located laterally beyond said planar central area at a distance radially inwardly from said interior side circular, peripheral edge; said distance from said peripheral edge being about 7% of the diameter of said peripheral edge; and  
       a resilient, flexible, connector sleeve having (1) a first end portion thereof connected with said marginal portion, and (2) a second end portion thereof connected with said head portion; the thickness of said sleeve being substantially constant between said first and second end portions; said connector sleeve having an interior surface for interfacing with the product and having an exterior surface for interfacing with ambient environment; said first end portion of said connector sleeve having a J-shaped cross section which extends into said marginal portion to facilitate movement of said head portion when dispensing product from the container; said sleeve exterior surface connecting with said head portion along a circular locus; said connector sleeve having a sidewall with a configuration which extends rollingly to shift said head portion outwardly when pressure within said container exceeds the exterior pressure by a predetermined amount;  
       each said slit outer end also being located at a distance radially inwardly from said circular locus; said distance from said circular locus being about 4% of the diameter of said circular locus; said orifice opening by outward displacement of said flaps when the pressure in the interior of the container exceeds the pressure on the exterior of the valve by a predetermined amount; and said orifice remaining open even when the pressure on the interior of the container does not exceed the pressure on the exterior of the valve.