| 摘要 |
A downhole rotation tool comprises a housing rotatable and axially slidable in relation to a gear shaft. The gear shaft is located interior of the housing. A tube gear is located intermediate the gear shaft and the housing. Helical threading on the gear shaft exterior interacts with helical threading interior of the tube gear to impart rotation of the tube gear upon linear movement of the gear shaft. A gear face at a lower end of the tube gear interacts with a corresponding gear face on the housing. Face gear teeth of the tube gear and the housing include axially-aligned engaging surfaces to rotate the housing in a preferred direction on downward stroke of the gear shaft and include inclined slip surfaces to allow relative rotation of the housing gear face and the tube gear face upon upward stroke of the gear shaft. |
