IMPLANTER HAVING AN IMPROVED CARTRIDGE EJECTOR

• US 3,744,493 A
• Filed: 01/10/1972
• Issued: 07/10/1973
• Est. Priority Date: 01/10/1972
• Status: Expired due to Term

• Current Assignee: George M Van Loozen, Keith E. Booher
• Original Assignee: George M Van Loozen, Keith E. Booher
• Inventors: Booher, Keith E., Van Loozen, George M.
• Primary Examiner(s): Gaudet, Richard A.
• Assistant Examiner(s): McGowan, J. C.
• Application Number:
  US05/216,559
• Time in Patent Office: 547 Days
• Field of Search: 128/217,264,218D,218F,223,238 42/1G,25 124/26,27,28,29,3R,41 221/197,198 222/326
• US Class Current: 604/62
• CPC Class Codes: A61M 37/0069 Devices for implanting pellets, e.g. markers or solid medicaments for introducing of radioactive sources for interstitial radiation therapy, i.e. brachytherapy A61N5/1027

Abstract

A pellet implanter includes a tubular body having a movable plunger therein extending from the rear end thereof through a hollow needle at the forward end thereof for pushing pellets from a pellet cartridge through the cartridge and through the hollow needle into the animal being treated. A side breech opening is provided in the body of the implanter. A cartridge ejector and stripper is provided proximate the rear end of the breech opening. The cartridge stripper and ejector includes a plug having a central bore for retaining the plunger therein against transverse translation. A forwardly projecting eccentric end portion of the ejector and stripper plug engages the rearwardly moving cartridge for stripping the cartridge from the plunger and for flipping the spent cartridge through the side breech opening, thereby ejecting same.

Claims

1. In an implanter, a tubular body member, a plunger extending into said tubular body from a rear end thereof and being axially movable within said body, a hollow needle member extending from the forward end of said tubular body, said tubular body including a side breech opening disposed intermediate the lEngth of said body for loading and ejecting spent pellet cartridges from said body, said tubular body including a pellet cartridge receiving chamber portion disposed between said side breech portion and said hollow needle for receiving and holding a pellet filled cartridge, said plunger being of a length sufficient to extend from the rear end of said body at least substantially through said hollow needle and being axially movable forwardly toward said hollow needle for pushing pellets contained in the pellet cartridge in said chamber from the cartridge and through said hollow needle, said plunger being axially retractable rearwardly of said body for pulling the spent cartridge, which clings to said plunger, from said chamber and for retracting said plunger to allow loading of a replacement cartridge, a cartridge ejector means disposed within said body proximate the rear end of said breech opening for stripping the spent pellet cartridge from the rearwardly moving plunger and for ejecting the spent cartridge from said body through said side breech opening, said cartridge ejector means including a cartridge stripping means inwardly protruding eccentrically of said body toward said plunger on the side thereof remote from the breech opening and being disposed forwardly of the rear end of said side breech opening for engaging the rear end of a spent cartridge for stripping the cartridge from the plunger and for flipping the stripped cartridge through said side breech opening, and generally fixed plunger retaining means disposed rearwardly of said stripping means proximate the rear end of said side breech opening for restraining transverse translation of said plunger in a direction away from said cartridge stripping means, whereby jamming of the spent cartridge in the body is prevented.

2. The apparatus of claim 1 wherein said plunger retaining means includes an apertured member disposed in said body proximate the rear end of said side breech opening with the aperture of said member being in coaxial alignment with said plunger to receive said plunger slideably therethrough and with the inside wall of said aperture serving to restrain transverse translation of said plunger.

3. The apparatus of claim 2 wherein said apertured member is a hollow cylindrical plug, and wherein said cartridge stripping means includes an eccentric end portion of said plug which projects forwardly therefrom into a region of said body in the rear portion of said side breech opening, said forwardly projecting portion of said plug terminating in a forward stripping face to engage the rear end of the spent cartridge, said forward stripping face being disposed on the side of said plunger opposite to said side breech opening.

4. The apparatus of claim 3 wherein said forward end of said plug includes a second face portion intersecting said forward stripping face portion, and said second face portion being slanted rearwardly from the intersection thereof with said stripping face portion toward the rear end of said side breech opening.

5. The apparatus of claim 4 wherein said second face portion of said plug is a section of a cylindrical surface, said cylindrical surface being inwardly dished of said plug and having an axis of revolution disposed forwardly of said plug on the side of said plunger opposite from said stripping face, and said axis of revolution being directed generally perpendicular to a longitudinal midplane of said side breech opening which includes the longitudinal axis of said plunger.

6. The apparatus of claim 1 wherein said plunger retaining means is disposed at the rear end of said side breech opening.