Kenneth M Tullio

US Patent:

53772164, Dec 27, 1994

Filed:

Jun 4, 1993

Appl. No.:

8/071395

Inventors:

Carl J. Nilsen - Flanders NJ
Walter Q. Wilson - Mr. Bethel PA
Kenneth M. Tullio - Bloomfield NJ

Assignee:

PRC Corporation - Landing NJ

International Classification:

H01S 3036
F16J 1546
F04B 3904

US Classification:

372 58

Abstract:

A turbine-type compressor useful in a gas laser apparatus for flowing gas along a flow path of the laser includes a sealing arrangement about a drive shaft of the compressor for preventing undesirable substances from moving to the compressor impeller along the drive shaft of the compressor and contaminating the laser gas compressed thereby. The sealing arrangement includes a first seal, preferably a vacuum pressure seal, for sealing about the shaft at least during rotation of the shaft, and a second seal comprising a resilient bladder which is selectively expanded and contracted to move into and out of sealing contact with the drive shaft, respectively, for, on one hand, sealing against the shaft when the drive shaft is stationary during pumping down of the laser and, on the other hand, withdrawing the bladder from the shaft when the shaft is rotating. The sealing arrangement is reliable and relatively low cost and uses less gas than a prior art sealing arrangement.