| 摘要 |
PURPOSE:To detect a grinding crack through a simple device and realize automatic, labor-saving grinding work by converting acoustic emission generated in grinding work into an electric signal, detecting its amplified signal after passing it through a band-pass filter, and generating a warning of the grinding crack when the detected value is larger than a set threshold value. CONSTITUTION:A grinding crack detector consists of a sensor 5 which is fitted to a chuck 3 and converts the acoustic emission into the electric signal, an amplifier 6 for the signal, a band-pass filter 7 connected to the amplifier 6, a detector 8, and an amplitude discriminator 9 which compares the amplitude of the output of the band-pass filter 7 with the set threshold value. Then, the AE generated in the grinding work is converted by the sensor 5 into the electric signal, which is amplified by the amplifier 6, passed through the band-pass filter 7 to remove the AE, mechanical noise, and electric noise generated in the normal grinding work, and detected by the detector 8. Then, a buzzer 10 sounds to warn a grinding crack when a value larger than the preset threshold value, e.g. 10mV is detected by the amplitude discriminator 9. |
