Ultrahigh Vacuum Mounting Fixture.
U S Pat 3 908 977 Sept 30 1975 :
A universal ultrahigh vacuum (less than 1 x 10-9 torr) mounting fixture. The device is an expansion fitting specifically designed for ultrahigh vacuum compatibility. A tapered plug has its front end inserted in a complementary shaped tapered hole in a sleeve. This sleeve has evenly spaced longitudinal slots that extend part of the way along and through the tapered surface. When in place, the sleeve extends through the wall of a vacuum chamber fitting into a vacuum flange mounting tube. A tightening bolt extends through the plug so that it may be turned from the rear of the plug, pulling the plug into the sleeve to rigidly expand the sleeve inside the flange mounting rigidly fixing the plug and sleeve in the flange mounting tube. A variety of different types of mounting posts may be attached to the front end of the plug to protrude into the chamber and mount the device under observation. The complementary tapers of the plug and hole are usually different with the plug having the greater taper. Because of the ultrahigh vacuum environment of the chamber, it is essential that only ultrahigh vacuum compatible materials like 300 series stainless steel, be used in constructing the invention.
U.S. Pat. 3,908,977, Sept. 30, 1975; Chem. Abstr. Not Found