DRILLING MACHINE, ROTARY BIT, AND ABRASION MEASUREMENT DEVICE FOR ROTARY BIT

摘要

PROBLEM TO BE SOLVED: To implement a mechanism for monitoring a rotation state and abrasion state of a rotary bit of a drilling machine, with a simple configuration.SOLUTION: An eddy current type displacement sensor 121 is disposed so that its longer direction agrees with the normal direction of a side face of a blade of a rotary bit 111 of a cutting head of a drilling machine. On the side face of the blade of the rotary bit 111 is provided a groove, for example, from the blade's tip to a rotation axis. A measurement value of the eddy current type displacement sensor 121 varies depending on the amount of abrasion of the blade of the rotary bit 111. The measurement value of the eddy current type displacement sensor 121 also shows a periodic peak in association with rotation of the rotary bit 111. Therefore, the abrasion state and rotation state of the rotary bit 111 are identified on the basis of the measurement value of the eddy current type displacement sensor 121.SELECTED DRAWING: Figure 3C