| 摘要 |
PROBLEM TO BE SOLVED: To provide a displacement detector for detecting a displacement of bonding wire easily and automatically. SOLUTION: The displacement detector is provided with a unwinding spool 1, a plurality of pulleys 4, 5, 6, 7 through which the bonding wire 2 passes, a strain gauge 3 mounted on a mounting stay for the pulley 4 through which the bonding wire 4 from the unwinding spool 1 firstly passes. There is also provided a means for detecting that bonding wire 2 on the unwinding spool 1 has been overtaken according to an excessive output voltage of the strain gauge 3 and an excessive pulse width of a pulse wave detected in the output voltage of the strain gauge 3. When detecting overtaking, an alarm lamp is lit to inform an operator of the overtaking. |
