Sterilization by low energy electron beam

Abstract

A sterilization apparatus wherein one or more electron beam tubes are used to direct electron beams into an ambient gaseous environment to create an electron plasma cloud into which non-sterile target objects may be moved. The electron plasma cloud is formed by interaction of the electron beam with the ambient atmosphere. Helium or other like gaseous may be used to expand the effective volume of the electron plasma cloud. Manipulators are used to move target objects in the electron plasma cloud, exposing non-sterile surfaces to the cloud and then joining the surfaces together where appropriate. The beam tube used to generate the electron beam has a thin low energy absorbing window which allows relatively low energy beams to be used, minimizing damage to materials within the surface of the target objects.

1. A sterilization apparatus comprising,
 an electron beam tube having a window permitting emergence of an electron beam from said tube into an ambient gaseous environment while preserving a vacuum environment in the tube, the electron beam having a trajectory within a plasma cloud defining a reactive volume stimulated by interaction of the electron beam with the ambient environment, with a beam energy less than  100 kV  keV  at the target, and  
 a moveable member manipulating objects in a plurality of directions within the reactive volume wherein the manipulated objects are sterilized.  
 
     
     
       2. The apparatus of  claim 1  further defined by a nozzle surrounding a window end of said beam tube and injecting a gas directed at the electron beam. 
     
     
       3. The apparatus of  claim 1  wherein the member is a robotic member having a robot hand and a robot arm. 
     
     
       4. The apparatus of  claim 1  wherein the member is a glove box hand capable of moving in any desired direction and capable of manipulating a variety of objects including different sized objects. 
     
     
       5. The apparatus of  claim 1  wherein a plurality of beam tubes have electron beams forming a common reactive volume. 
     
     
       6. The apparatus of  claim 5  wherein the beam tubes are sufficient in number and arrangement to avoid shadows on specific objects placed in the reactive volume. 
     
     
       7. The apparatus of  claim 1  further defined by a housing containing the ambient environment. 
     
     
       8. The apparatus of  claim 7  wherein the housing has ports for insertion of material to be sterilized. 
     
     
       9. The apparatus of  claim 1  further comprising magnetic means for steering the electron beam between the window and the plasma cloud. 
     
     
       10. The apparatus of  claim 1  further comprising magnetic means for shaping the electron beam between the window and the plasma cloud. 
     
     
       11. A sterilization apparatus comprising,
 a chamber with ports allowing insertion of objects to be sterilized and having a gaseous environment therein,  
 a plurality of vacuum tubes fixed relative to the chamber, each emitting an electron beam along a path into the chamber through a window separating the gaseous environment of the chamber from the vacuum of the tube, the beam paths from the tubes within a common plasma cloud stimulated by the electron beams interacting with the gaseous environment within the chamber, defining a volume associated with the plasma cloud wherein the objects to be sterilized are exposed to the plasma cloud, and  
 at least one moveable member manipulating objects in a plurality of directions in the reactive volume wherein manipulated objects are sterilized.  
 
     
     
       12. The apparatus of  claim 11  further defined by a nozzle surrounding a window end of each beam tube and injecting a gas directed at each electron beam from each tube. 
     
     
       13. The apparatus of  claim 12  wherein the injected gas is helium. 
     
     
       14. The apparatus of  claim 12  wherein the injected gas is argon. 
     
     
       15. The apparatus of  claim 11  wherein the chamber is a glove box hand capable of moving in any desired direction and capable of manipulating a variety of objects including different sized objects. 
     
     
       16. The apparatus of  claim 11  wherein the gaseous environment is an air environment. 
     
     
       17. The apparatus of  claim 11  wherein the gaseous environment is at atmospheric pressure. 
     
     
       18. A sterilization apparatus comprising,
 a single electron beam tube having a window permitting emergence of an electron beam from said tube into an ambient gaseous environment while preserving a vacuum environment in the tube, the electron beam having a trajectory within a plasma cloud defining a reactive volume stimulated by interaction of the electron beam with the ambient environment, with a beam of energy less than  100 kV  keV  at the target, and  
 a glove box hand and a robotic member having a robotic hand and a robotic arm, said glove box hand and robotic member manipulating objects, the glove box hand manipulating objects including objects that differ in variety, size and shape from the objects manipulated by said robotic hand, in a plurality of directions within the reactive volume wherein the manipulated objects are sterilized by said single electron beam tube.