ROD REPLACEMENT DEVICE

PURPOSE: To protect damages to rods by installing a shock absorbing means to a rod receiving part of a rod magazine and a rod clamp device and supporting a rod housed in the magazine movably in the longitudinal direction of the rod. CONSTITUTION: An inner pipe Ri and an outer pipe Ro housed in a rod magazine 2 are supported respectively by way of an inner pipe support pin 23a and an outer pipe receiving material 26 while type are elastically supported with springs 27 and 28 in a movable state in the longitudinal direction. Then, an outer pipe clamp 4 and an inner pipe clamp 5 of a clamp device 3 are elastically supported substantially in a similar fashion. Then, when a drifter of a boring machine is connected to and removed from the inner pipe Ri and the outer pipe Ro, if the forward length or the backward length of the drifter is too longer than its screw length and the pipes Ri and Ro are subjected to the thrust of the drifter, the inner pipe Ri and the outer pipe Ro will move by an extra movement of the drifter by the shrinkage of springs 27 and 28. This construction makes is possible to protect a thread ridge from being crushed and the rod magazine and the clamps or the like from being damaged.