| 摘要 |
PROBLEM TO BE SOLVED: To externally detect intrusion of foreign substance and remove it for safe operation by keeping a part of lubricant supplied to a seal structure part at a rotation support part of a cutter head at a specified pressure in a lubricant chamber, which is externally circulated with a supply pump. SOLUTION: Related to a seal structure part provided to a cutter head rotation support part of a tunnel excavator, a lubricant supplied into a lubricant chamber 26a formed between a plurality of seals is supplied through an injection opening 17 while the pressure condition of the lubricant chamber 26a is kept. It is taken out through a discharge opening 18 and supplied again while connected to a circulation supply pump 20 for the lubricant. The foreign substance in the lubricant discharged through a filter 33 provided on its taking-out side is detected based on sticking of it to the filter material, for removal and circulation. |
