Hitachi TM3000 Instruction Manual page 242

NOTE : Since the liner pipe is thin and easily bent, when pulling it out, pull it straight up.
6. Remove the objective aperture unit; replace the objective aperture unit.
Grasp the center of the liner pipe, and using a slotted screwdriver, turn the stopper at the tip
counterclockwise to take out the objective aperture unit. Use the slotted screwdriver by
cleaning its tip in advance with alcohol. In the next step, disassemble the objective aperture
unit, and install a new objective aperture unit. Because it is thin and easily deformed, use
adequate care in installing it. Also, since the open hole on the objective aperture is extremely
small, scratches and the adhesion of particles can reduce image quality. When handling the
objective aperture unit, exercise adequate so that dust and particles will not get onto it.
Figure 5.4-5
Removing the Objective Aperture Unit
7. Install the objective aperture unit into the liner pipe.
When finished with replacing the objective aperture, use a slotted screwdriver to attach the
objective aperture unit to the tip of the liner pipe by performing the reverse procedure of Step
6. above. Finally, apply a small amount of the supplied vacuum grease by thinly spreading it
onto the o-ring on the liner pipe.
Figure 5.4-4 Pulling the Liner Pipe Out (2)
Stopper
5 - 25
Liner pipe
Figure 5.4-6
Disassembling the Objective Aperture Unit
Spacer
Objective aperture
Aperture holder