| 摘要 |
PURPOSE:To enable a breaking AE signal to be positively arrested instantly before it is damped by connecting a pressor member of a printed substrate with an AE sensor mounted on a stationary member which is held in a condition separated from a boring machine, with a flexible conductor. CONSTITUTION:When a drill 5 is broken during drilling, AE waves produced by drill breaking are transferred from a breakage to a printed substrate 1 and to a pressor member 3. And AE waves between the pressor member 3 and a stationary member 6 are transferred to the stationary member via a flexible conductor without being damped. And they are transferred from a holder 8 further down to an AE sensor 7 so as to be inputted into a signal processing circuit 10 for outputting a drill breaking signal. Owing to this constitution, a breaking AE signal can be positively arrested instantly before it is damped. |
