APPARATUS FOR DISPENSING LOW VISCOSITY SEMI-FLUID MATERIAL UNDER PRESSURE

摘要

An injection gun especially useful for injecting low volume, high pressure shots of bone cement. The gun includes a cylindrical housing with a plunger including a plunger rod extending axially through the housing. The plunger rod includes a segment which is provided with an axial series of notches. A ratchet block is slidable axially within the cylindrical housing and is concentric with the plunger rod. The ratchet cylinder mounts at least a ratchet pawl urged against the plunger rod and adapted to engage and lock into the series of notches for forward movement. A pistol grip extends from the cylindrical housing, and a lever is pivoted thereto with an extension of the lever engaging the ratchet cylinder for advancing the plunger. A second ratchet pawl is mounted on a fixed member of the cylindrical housing for retaining the plunger against rearward movement when the pawl in the ratchet cylinder is disengaged from the rod.