Hallock F Swift

US Patent:

52458687, Sep 21, 1993

Filed:

Jan 3, 1992

Appl. No.:

7/817273

Inventors:

John J. Lacey - Minnetonka MN
George J. Streithorst - Lebanon OH
Hallock F. Swift - Dayton OH

Assignee:

Fluidyne Engineering Corporation - Minneapolis MN

International Classification:

G01M 900

US Classification:

73147

Abstract:

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.