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:
Oct. 20, 1992
Filed:
Apr. 26, 1991
Leybold Aktiengesellschaft, Hanau, DE;
Abstract
The invention relates to a method of making a pump ring for a two-stage vacuum pump (1) with a one-piece rotor system (14) having three sections (14a, b, c), whose end sections (14a and 14c form the two pumping stages and whose middle section (14b) forms an intermediate bearing, the diameters of the bearing section (14band of the rotor section (14a) forming the forepumping stage being equal. To reduce the tolerances that occur it is proposed that two bores be made in a single set-up from one end of a substantially cylindrical workpiece, the one forming the anchor contact (51) of the forepumping stage as well as the bearing bore (12) and the other forming the anchor contact (52) of the high-vacuum stage, and that before or after these bores aremade, additional bores (11, 13) are made in order to form the pump chambers (21, 17).