摘要 |
PCT No. PCT/SE93/01057 Sec. 371 Date Jun. 14, 1995 Sec. 102(e) Date Jun. 14, 1995 PCT Filed Dec. 8, 1993 PCT Pub. No. WO94/15100 PCT Pub. Date Jul. 7, 1994A rotary screw compressor for oil-free air, wherein at least one of the shaft journals (11) of the rotors (10) has a seal arrangement between the rotor (10d) and an oil-lubricated bearing (12). The seal arrangement includes at least three frictionless seals (13, 14, 15) separated by annular chambers (16,17). The outermost annular chamber (17) is connected to a source of pressurized air through a supply channel (19) for supplying blocking air to the seal, and another (16) of the annular chambers communicates with a withdrawal channel (18). |