| 摘要 |
PURPOSE:To feed oil stably to a shaft and a bearing, by press-fitting a circular pipe into an axial bore in a shaft, formed therein with a spiral oil groove having spiral pitches decreasing upward. CONSTITUTION:A circular pipe 13' is inserted in an axial bore 9' in a shaft 3' in which there is formed a spiral oil groove 10' having pitches decreasing upward, and therefore, the oil groove 10' is substantially covered. Lublication oil 8' which comes up through the passage defined between the axial bore 9' and the circular pipe 13', easily rises since the higher the spiral oil groove 10' the smaller the pitches is. The sealing ability of the passage is satisfactory since the circular pipe is press-fitted into the axial bore, and therefore, the leakage of lubrication oil is relatively small. Further, by forming a recess groove in the circular pipe 13' in a position corresponding to the spiral groove 10', the passage for lubrication oil 8' is enlarged so that the feed rate of lubrication oil is increased. |
