Patent ID: 6102895
Filing Date: 2000-08-15
Classification: A61B,A61F,A61M

Abstract:
A device for delivering discrete doses of fluidic material into tissue, the device comprising:a housing having an aperture and containing a piston, said piston capable of being moved by a force;a syringe having a needle receiving end, a plunger receiving end, and a hollow barrel between said needle receiving end and said plunger receiving end, said plunger receiving end of said syringe attached to said housing at said aperture;a plunger having a periphery and a length; said plunger having teeth on at least a portion of said periphery for at least a portion of said length, said plunger capable of passing through said aperture in said housing and said plunger receiving end of said barrel of said syringe;a ratcheting mechanism within said housing; said ratcheting mechanism capable of engaging said teeth of said plunger such that when said ratcheting mechanism moves within said housing toward said syringe, said plunger is caused to move within said barrel toward said needle receiving end of said syringe, said ratcheting mechanism capable of being disengaged from said teeth of said plunger such that when said ratcheting mechanism moves within said housing, said plunger is not caused to move within said barrel; anda mechanical linkage coupled between the ratcheting mechanism and the piston, for interrelating movement of said piston to movement of said ratcheting mechanism such that when said piston moves a distance, said ratcheting mechanism moves a related distance and such that said force moving said piston is translated into a related force provided to move said ratcheting mechanism said mechanical linkage further comprises a lever arm and a fulcrum on which said lever arm acts, said lever arm pivotably attached to said ratcheting mechanism at a ratchet pivot point, said lever arm pivotably attached to said piston at a piston pivot point;said lever arm is capable of interrelating movement of said piston pivot point to movement of said ratchet pivot point such that when said piston pivot point moves a distance, said ratchet pivot point moves a shorter distance; andsaid lever arm is capable of translating a force applied at said piston point to a greater force provided at said ratchet pivot point.