Gas discharge laser with roller bearings and stable magnetic axial positioning

Claim 1

An electric discharge gas laser comprising: A. a housing structure having walls forming an internal laser cavity; B. a gas located within the laser cavity to define a gas environment, said gas being capable of lasing action; C. a pair of elongated spaced electrodes located within the laser cavity and forming an electrical discharge region between the electrodes for stimulating gas within the discharge region to lasing action in accordance with an electrical discharge between the electrodes; D. a rotating fan, having a shaft defining a shaft axis, located within the laser cavity for circulating the gas through the discharge region; E. at least two cylindrical roller bearings providing radial support to said shaft but no axial support for said shaft; F. a brushless DC motor comprising a stator defining a stator axial reluctance center, and a rotor defining a rotor axial reluctance center, for providing rotation to the fan, said rotor of said motor being coupled directly or indirectly to said shaft; G. a magnetic means for providing a magnetic axial force for axially positioning said shaft; and H. at least one sealing member interposed between said rotor and said stator to seal said rotor within the gas environment and to seal the stator outside the gas environment; wherein radial support for said shaft is provided by said roller bearings and axial positioning of said shaft is provided by said magnetic means.