| 摘要 |
The oil in the stern tube is normally maintained at a predetermined pressure. A conduit leading from a source of compressed air has an outlet in the region of the center line of the tail shaft, the air in said conduit being at a pressure to normally bleed air from the outlet, and there being valve means in said conduit between the source of compressed air and the outlet which is responsive to changes in the air pressure in the conduit, caused by changes in the draft of the ship, for varying the oil pressure in the oil chamber to maintain it at a predetermined value above sea pressure. In one form of the invention the air pressure in the conduit serves as a medium to transmit changes in the draft of the ship to the oil in a closed head tank. In another form of the invention the air pressure in the conduit acts to control the flow of oil from an elevated head tank to thereby control the pressure in the stern tube, and in another form of the invention the air pressure in the conduit acts to control the effective pressure of the oil being delivered to the stern tube by a pressure pump.
|
