PURPOSE: To prevent troubles such as mixture of shaft sealing oil and lubricating oil or oil leakage from a shaft edge part by setting a structure in such a way that seal nozzles, guide plates and drain holes are provided and leaked oil stored in a labyrinth part is discharged positively.

CONSTITUTION: An atomized oil component can be removed completely by means of air blown off from a seal air blowing nozzle 3 on the outer diameter surface of an oil thrower ring 2 so as to be carried outside from vent nozzles 7. Furthermore, seal air blown off from the seal air blowning nozzle 3 is flowed equally to the right and left sides by means of a perpendicular projection arranged in the central part of the oil thrower ring 2. Since guide plates 4 arranged on both sides of the oil thrower ring 2 have guides on the inner diameter surface and the outer diameter surface so that the oil thrown away by means of a projection part on the outer edge surface of the oil thrower ring 2 can not adhere to a shaft 1, the oil can be collected to one place smoothly, so that the oil can be discharged outside from the lower part of the guide plates 4 through oil drain ports 8. Meanwhile, drain holes 6 are arranged in the lower part of a seal labyrinth 5 so that the oil leaked to the seal labyrinth 5 can be discharged positively.