Patent ID: 6516934
Filing Date: 2003-02-11
Classification: B65G,F15B,F16C

Abstract:
A pneumatic pop-up unit comprising:(a) a housing having a bottom wall, a side wall extending upwardly from said bottom wall, a flange extending outwardly from the top of said side wall, and an open top; (b) a piston slidable within said housing between a lower position and an upper position, said piston having an upper opening; (c) a contact element seated within said piston and partially extending through the upper opening of the piston; (d) a cap positioned on top of said open top of said housing and secured to said flange of said housing, said cap having a central opening through which said contact element partially extends when said piston is in said upper position; (e) a spring for biasing said piston toward said lower position; and (f) a nipple mounted in said housing for use in admitting fluid under pressure to said housing to elevate said piston against the bias of said spring toward said upper position.