Patent ID: 8794254

Claim:
A passive closing device comprising: a main body comprising a bore in fluid communication with a passage, the bore extending from an exterior of the body to the passage, the bore comprising a seat between the bore and the passage, the passage extending to the exterior of the body; and a thermally responsive element coupled to the body, the thermally responsive element comprising: a sleeve comprising a first opening and a second opening; and a piston positioned within the sleeve, the piston comprising a first end exiting the first opening, a second end exiting the second opening, and a member partitioning a thermally responsive material within the sleeve from a space within the sleeve, wherein the thermally responsive material expands at a threshold temperature to urge the member toward the space and extends the first end of the piston from the sleeve while the second end retracts toward the sleeve, wherein the first end of the piston is disposed within the body and configured to engage the seat to seal the bore from the passage.