In-line pressure check valve for drug-delivery systems

A pressure control valve, comprising:

• a substrate having a central orifice therethrough, and having a sealed chamber therein with said chamber's top being defined by a flexible membrane;
• an inlet control element, coupled around its perimeter to said membrane such that said inlet control element is disposed above said central orifice, and normally defines a gap between said inlet control element and said substrate, said inlet control element having a plurality of holes therethrough;
• said valve normally having a fluid path therethrough whereby fluid enters through said plurality of holes, passes through said gap, and exits through said central orifice;
• wherein a pressure differential, between external pressure and pressure in said chamber, above a predetermined threshold, causes deformation of said membrane, drawing said inlet control element toward said substrate and eliminating said gap, such that said fluid path is interrupted.

A pressure control valve having a normally open configuration and a closed configuration, said valve comprising:

• a substrate, having at least one hole therein providing a fluid path through said valve;
• a flexible membrane, coupled to said substrate;
• and
• a valve lid, coupled to said membrane such that pressure exerted on said valve lid is applied to said membrane, said membrane flexing in response to such pressure, said valve lid extending over said at least one hole in said substrate;
• wherein when no pressure is applied to said valve lid, a valve gap is defined between said valve lid and said substrate, such that fluid is permitted to flow through said at least one hole;
• and wherein when pressure applied to said valve lid causing said membrane to flex draws said valve lid toward said membrane, said valve gap narrows, such that pressure above a predetermined level applied to said valve lid closes said gap and prevents fluid from flowing through said at least one hole.