Disc for a turbomolecular pump

Abstract

A disc for a turbomolecular pump formed of a plurality of disc elements assembled in an axial direction and each having a support ring, a plurality of vanes supported on the support ring and inclined to a plane of the support ring, and a plurality of radially extending slots provided between the vanes, with the support rings of the disc elements forming the support ring of the disc, the vanes of the disc elements forming the disc vanes, and the radial slots provided between the vanes of the disc elements forming the radially extending slots between the disc vanes, and with the vanes of one of disc elements least partially covering the radially extending slots of an adjacent disc element.

What is claimed is:  
     
         1 . A disc for a turbomolecular pump, comprising a support ring; a plurality of vanes supported on the support rings, inclined to a plane of the support disc, and forming a circle; and a plurality of radially extending slots provided between the vanes, 
 Wherein the disc is formed of a plurality of disc elements assembled in an axial direction and each having a support ring, a plurality of vanes supported on the support ring and inclined to a plane of the support ring, and a plurality of radially extending slots provided between the vanes,    Wherein the support rings of the disc elements form the support ring of the disc, the vanes of the disc elements form the disc vanes, and the radially extending slots provided between the vanes of the disc elements form the radially extending slots between the disc vanes, and    Wherein in the assembled condition of the disc, the vanes of one of the plurality of disc elements at least partially cover the radially extending slots of an adjacent disc element.    
     
     
         2 . A disc as set forth in  claim 1 , wherein the vanes of the disc elements forming an optically infermeable surface in the axial direction.  
     
     
         3 . A disc as set forth in  claim 1 , wherein the disc elements are formed as sheet metal body, with the vanes being stamped out of a disc element plane.