Replacement of air-cylinder for mirror house movement

Daniel Öijerholm, Anders Liljeborg, 2009-02-17

1. Disconnect main power
2. Disconnect optical fibers to microscope
3. Take off microscope:
   • Left side, slider locked by two screws, open them by hand
   • Lift microscope straight up
4. In front, directly behind sample table, two hex screws, M4, on front corners of plate where mirror house is mounted, unmount screws.
5. Disconnect plug from microscope manipulator and pneumatic connector
6. Lift up the the mirror house completely, it swings backwards on two hinges at the back. There is a mechanical stop inside, at left, see to it that it snaps into locked position.
7. Inside of this plate, the mounting block for cylinder is fastened by two hex screws and two air pipes, 7, 8. Disconnect air pipes, dismount screws.
8. Take out the front lens by sliding it to the left,
9. At front end of air cylinder there are two nuts, take them off completely.
10. Unmount the block that the front of the cylinder piston is fastened to.
11. Unmount the front stop.
12. Slide the mirror house all the way off the slider (dovetail) and put it on the side, some more tubes and cables must be disconnected.
13. The cylinder is now visible. On the underside the angled connectors for the air-tubes has to be removed in order to lift out the cylinder.
14. Mount new cylinder, leave a little space, 0.1-0.3 mm, between nuts where the piston is mounted to the block on the mirror house.
15. The piston was not centered in the hole in the mounting block on the mirror house, fastening screws for cylinder was loosened to make adjustment to center piston. This was not possible but the piston was at least not pressing on the mounting block.
16. All was assembled again.
17. There was rather high friction at the back end of the mirror house movement. Tried to adjust ball bearing screws at front of mirror house, right next to front lens. These screws are supposed to adjust height of a ball bearing so that sliding friction is lower, i.e. the mirror house is more rolling than sliding.
    This did not make a big difference. The advice from Karl Süss was to do this and lubricate with "sticky" fat to make the slider move with more even friction.
18. Adjust movement by throttles at left side, set exposure time to 1-2 seconds, whole system turned on, contact mode for testing. Very difficult to get forward motion to be smooth and soft, backward motion worked fine.
    Forward motion either not moving at all, or too fast, slamming into the front stop.
19. When moving the microscope manipulator to center position, suddenly the forward motion became good.
20. Left the system in this state for general use.

Pictures taken at service 20121210

Front microscope removed, two screws removed and lifted upwards / backwards.
Also front lens removed.

The two air-connectors for the piston (7) and (8). Tubes removed. Beside the connectors are the two fastening screws. They are difficult to insert due to washers on the inside, they have to be positioned with a small screwdriver and an inspection mirror.

Front mount for air piston. Note double nut in center and black fastening hex-screws for the mounting block on either side. Below that is the front stop for the mirror house movement.

The front mount removed and the entire mirror house slid away from the dove tail. The air piston in the center. The two black hoses are the fibre optic cables for the microscope illumination.

Same, but from another angle.

The under side of the mirror house.
Note the spring loaded dampers for the forward and backwards movement.

Overview.

Overview.