| 摘要 |
<p>PURPOSE:To prevent a radioactive substance from mixing to a cathode cylinder by providing a slope in the side face of a cap-shaped substance metal, which is fixed to one end of the cathode cylinder incorporating a heater by welding, to make it possible for an electron radioactive substance spray hold frame, which is caused to adhere onto the substance metal face, to approach the cap. CONSTITUTION:Cap-shaped substance metal 9 where the side face is inclined at 45 deg. to 60 deg. in respect to the center is fixed to the outside of one end of sleeve 8, which is a cylindrical cathode cylinder incorporating a heater, by welding. Next, only the upper face of substance metal 9 is covered with electron radioactive substance 10 of (BaSrGa) CO3, and the other end of sleeve 8 is fixed to cylindrical cathode support body 12 through plural rows of straps 11. By this constitution, when radioactive substance 10 is applied by the spray method, spray hold frame 15 can be closely sticked to the side face of metal 9 because the side face of substance metal 9 is inclined. As a result, radioactive substance 10 adheres only to the plane part of metal 9 and is prevented from reacting on Cr included in sleeve 8.</p> |
