US Patent 8211187 Elevated vacuum locking system

Elevated vacuum locking systems for prosthetic limbs are disclosed. Some example embodiments may include a manifold mounted to the exterior of the distal end of a socket and may include a cavity adapted to receive a distal end of a plunger pin when the patient's residual limb and a liner are installed into the socket. Some example manifolds may include a through passage fluidicly connecting an interior of the cavity to a fitting mounted on an exterior of the manifold and/or a spool valve arranged to selectively vent the cavity to atmosphere via the through passage and a vent hole. The spool valve may be axially slidable between an open position and a shut position within a channel integrally formed with the manifold.