Piston stop for free piston shock tube/tunnel

摘要

A free piston shock tube/tunnel having a mechanism for stopping the piston or controlling the movement of the piston near the diaphragm end of the compression tube. The mechanism includes a generally annular protrusion positioned at the diaphragm end of the compression tube and extending upstream from the diaphragm to engage the piston at a point where the velocity of the piston is substantially at a minimum. The annular protrusion is spaced inwardly from the compression tube and has an inner diameter greater than the diameter of the shock tube.