Patent ID: 6328547
Filing Date: 2001-12-11
Classification: F04C

Abstract:
A rotary pump which comprises(a) a pump casing,(b) a casing cover for defining a pumping chamber with said pump casing,(c) a pair of rotors within said pumping chamber and having end surfaces adjacent to said casing cover, and pumping segments engaged with each other for synchronous revolution in mutually opposing directions, within said pumping chamber,(d) a gearbox, adjacent to said pump casing,(e) synchronous driving gears disposed within said gearbox,(f) a pair of hollow rotor drive shafts having a hollow portion, and an outer end, each of said drive shafts being interconnected with each of said rotors for integral rotation therewith, said drive shafts being supported in said gearbox and being coupled to one another by said driving gears, each of said driving gears being mounted on each of said drive shafts in a mutually meshing condition with said hollow rotor drive shafts being synchronously rotated in mutually opposite directions and meshing with said drive gears,(g) a pair of rotor fastening bolts, each having a bolt head at one end thereof, said bolt being inserted into a hollow portion of a hollow rotor drive shaft and being tightened for securing one of said rotors to one of said hollow rotor drive shafts with said bolt head being anchored to the outer end of said rotor drive shaft,(h) an extended drive shaft portion formed by one of said hollow rotor drive shafts extending outwardly from the gear box,(i) a cylindrical transmission coupling having an operating space, and being coupled with said extended drive shaft portion for integral rotation therewith with said operating space accommodating the bolt head of the rotor fastening bolt.