Ulvac EGL-206M, Instruction Manual

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SECTION 5
24
5. DISASSEMBLY AND REASSEMBLY OF ELECTRON BEAM GUN
In disassembling or reassembling the electron beam gun, be sure to wear
clean gloves. Turn OFF the MAIN switch on the electron beam gun power
supply. Remove the key and keep it yourself.
5.1 Changing Filament
(1) Dismounting the emitter assembly
Remove the screw that clamps the filament cable to the terminal. The
emitter assembly can be removed downward by turning the two setscrews
(knurled) on the front of the unit two to three turns to loosen them.
CAUTION
After operation of an EB GUN, EB GUN, especially an emitter assembly
periphery, evaporation material, filament cables and high voltage
feed-through terminals become high temperature. Take care not to burn
yourself.
(2) Removing the filament
The filament can be removed by loosening the filament setscrews alternately
with an Allen wrench.
(3) Mounting the filament
Place a new filament on the filament holder and lightly fix it with the filament
support and filament setscrews. Hold the filament leg with a pair of
tweezers and firmly tighten the filament setscrews with the filament lightly
held down.
NOTE
1. Set the filament correctly with referring to the figure carefully.
2. Location dimension of the filament, the beam former and the anode plate
are critical for the electron beam gun. Set them at correct position.
3. A filament set screw is coated by rolled gold to prevent crack of the screw.
Do not mingle them with other screws.