Bearings – Linear bearing – Fluid bearing
Patent
1990-06-08
1992-03-24
Hannon, Thomas R.
Bearings
Linear bearing
Fluid bearing
384 9, F16C 3206
Patent
active
050982044
ABSTRACT:
ATE is mounted directly to a support surrounding and removably receiving probe cards of differing thickness. An electrically heated chuck having a variable heat transfer coefficient heat exchanging face confronting a liquid nitrogen supplied plenum exhibits a temperature that varies with electrical heater load, rate of liquid nitrogen supply, and heat transfer coefficient of the heat exchanging face. The rate of liquid nitrogen supply is varied as a function of whether or not the electrical heater load falls outside predetermined upper and lower bounds to establish and maintain set point temperature over a range of set point temperatures including liquid nitrogen temperature and ambient temperature. The chuck is mounted for X,Y movement on load-balanced air/vacuum bearing, and is mounted for Z movement to accommodate different thickness probe cards. A load-lock having a pivoting cassette receiving tray that pivots with a pivoting transfer arm is mounted for Z movement with the chuck. A vacuum pump selectively lowers the temperature at which the supplied liquid nitrogen boils. A positive pressure of N.sub.2 gas is maintained to prevent moisture condensation in the load-lock and on the operative surfaces of the chuck.
REFERENCES:
patent: 3437929 (1969-04-01), Glen
patent: 3953013 (1976-04-01), Griffith et al.
patent: 4190240 (1980-02-01), Peterson
patent: 4532423 (1985-07-01), Tojo et al.
patent: 4546619 (1985-10-01), Rohner
patent: 4717263 (1988-01-01), Phillips
patent: 4719705 (1988-01-01), Laganza et al.
patent: 4747450 (1988-05-01), Ikegame et al.
patent: 4747589 (1988-03-01), Watson et al.
patent: 4757255 (1988-07-01), Margozzi
patent: 4799009 (1989-01-01), Tada et al.
patent: 4856904 (1989-08-01), Akagawa
patent: 4954744 (1990-09-01), Binet
Hannon Thomas R.
John H. Blanz Company, Inc.
LandOfFree
Load balanced planar bearing assembly especially for a cryogenic does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Load balanced planar bearing assembly especially for a cryogenic, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Load balanced planar bearing assembly especially for a cryogenic will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2005131