摘要 |
A drilling tool that has a flexible shaft so as to be able to make short radius curves while still being able to transmit torque and axial loads. The drilling tool includes a drill shaft for transmitting axial load, comprising a series of coaxial ring members connected together such that adjacent ring members are flexible in an axial plane relative to each other, each ring member being connected to an adjacent ring member by connecting member arranged to transmit torque therebetween; and axial supports extend between adjacent ring members so as to transmit axial loads therebetween. |