Patent ID: 8863781

Claim:
A valve apparatus comprising: a valve housing structure; a first valve portion connected to the valve housing structure, wherein the first valve portion has a sealing edge; a second valve portion positioned at least partially within the valve housing structure, wherein the second valve portion further comprises an upper valve part and a lower valve part having a gap positioned between the upper and lower valve parts; and a constrictable membrane having a pressurizable interior compartment, the constrictable membrane supported by the second valve portion and positioned proximate to the first valve portion, wherein at least a portion of the constrictable membrane is movable to be engageable with the sealing edge of the first valve portion, wherein the constrictable membrane is affixed between the upper and lower valve parts and across the gap, wherein the sealing edge of the first valve portion is positioned within the gap formed between the upper and lower valve parts, wherein the constrictable membrane is movable between at least a first position where the constrictable membrane engages the sealing edge of the first valve portion to create a seal, and a second position where the constrictable membrane does not contact the sealing edge of the first valve portion.