Liquid-Ring Vacuum Pump and Impeller for a Liquid-Ring Vacuum Pump

Abstract

A liquid-ring vacuum pump comprises a pump casing and an impeller that is eccentrically mounted in the pump casing. The impeller is made of a material having a modulus of elasticity of less than 4000 N/mm 2 .

1 . A liquid-ring vacuum pump having a pump housing and an impeller which is mounted eccentrically in the pump housing, characterized in that the impeller is composed of a material having a modulus of elasticity of which is smaller than 4000 N/mm 2 . 
     
     
         2 . The liquid-ring vacuum pump as claimed in  claim 1 , characterized in that the impeller is composed of a non-fiber-reinforced material. 
     
     
         3 . The liquid-ring vacuum pump as claimed in  claim 1 , characterized in that the impeller has a homogeneous surface. 
     
     
         4 . The liquid-ring vacuum pump as claimed in  claim 1 , characterized in that the impeller is composed of a plastic material. 
     
     
         5 . The liquid-ring vacuum pump as claimed in  claim 4 , characterized in that the impeller is composed of polyoxymethylene (POM), polyether ether ketones (PEEK), polyamides (PA), polybutylene terephthalate (PBT), polycarbonates (PC) or polyphenylene sulfide (PPS). 
     
     
         6 . The liquid-ring vacuum pump as claimed in  claim 1 , characterized in that the material of the impeller has a modulus of elasticity of at least 2000 N/mm 2 . 
     
     
         7 . The liquid-ring vacuum pump as claimed in  claim 1 , characterized in that the impeller has a plurality of vanes which lies between 10 and 20. 
     
     
         8 . The liquid-ring vacuum pump as claimed in  claim 1 , characterized in that the impeller has a disk-shaped projection which extends radially to the outside from a hub and protrudes into the liquid ring during operation of the pump. 
     
     
         9 . The liquid-ring vacuum pump as claimed in  claim 8 , characterized in that the impeller has a plurality of vanes which protrude further into the liquid ring than the disk-shaped projection. 
     
     
         10 . An impeller for a liquid-ring vacuum pump of this type as claimed in  claim 1 , having a hub for a tight connection to an eccentrically mounted shaft of the pump, having a plurality of vanes which extend radially to an outside from the hub, the vanes being covered by a disk-shaped projection on one end side over at least half of their radial extent, characterized in that the impeller is composed of a material having a modulus of elasticity of which is smaller than 4000 N/mm 2 . 
     
     
         11 . The liquid-ring vacuum pump as claimed in  claim 2 , characterized in that the impeller has a homogeneous surface. 
     
     
         12 . The liquid-ring vacuum pump as claimed in  claim 2 , characterized in that the material of the impeller has a modulus of elasticity of at least 2000 N/mm 2 . 
     
     
         13 . The liquid-ring vacuum pump as claimed in  claim 3 , characterized in that the material of the impeller has a modulus of elasticity of at least 2000 N/mm 2 . 
     
     
         14 . The liquid-ring vacuum pump as claimed in  claim 4 , characterized in that the material of the impeller has a modulus of elasticity of at least 2000 N/mm 2 . 
     
     
         15 . The liquid-ring vacuum pump as claimed in  claim 5 , characterized in that the material of the impeller has a modulus of elasticity of at least 2000 N/mm 2 . 
     
     
         16 . The liquid-ring vacuum pump as claimed in  claim 2 , characterized in that the impeller has a plurality of vanes which lies between 10 and 20. 
     
     
         17 . The liquid-ring vacuum pump as claimed in  claim 3 , characterized in that the impeller has a plurality of vanes which lies between 10 and 20. 
     
     
         18 . The liquid-ring vacuum pump as claimed in  claim 4 , characterized in that the impeller has a plurality of vanes which lies between 10 and 20. 
     
     
         19 . The liquid-ring vacuum pump as claimed in  claim 5 , characterized in that the impeller has a plurality of vanes which lies between 10 and 20. 
     
     
         20 . The liquid-ring vacuum pump as claimed in  claim 6 , characterized in that the impeller has a plurality of vanes which lies between 10 and 20.