The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 03, 2002
Filed:
Feb. 10, 2000
Norman E. Wandke, Naperville, IL (US);
Mark S. Maska, Palatine, IL (US);
Donald C. Mueller, Aurora, IL (US);
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
A high energy x-ray tube includes an evacuated chamber ( ) containing a rotor ( ) which rotates an anode ( ) in the path of a stream of electrons (A) to generate an x-rays (B) and heat. The rotor includes a bearing shaft ( ) connected to the anode by a thermally conductive structure ( ). The bearing shaft carries soft metal-lubricated bearing balls ( F, R) in forward and rear bearing races ( ). An annular groove ( ) is defined longitudinally in the shaft which, particularly when evacuated, provides a thermal barrier between the forward race and the portion of the shaft that is thermally connected with the anode. The groove lengthens the path heat entering the bearing shaft travels in order to reach the forward bearing race. As a result, the temperature of the forward race, and hence the evaporation of lubricant during operation of the x-ray tube, is reduced. The groove may be formed by electrical discharge machining the bearing shaft or by forming the shaft from inner and peripheral components ( ) which are connected together adjacent the rear bearing race ( ).