| 摘要 |
PURPOSE:To enable the press work of high accuracy with controlling a bottom dead point to become at constant position by varying a press speed. CONSTITUTION:A press machine has the bottom dead point position detecting part 6 to equip the position detecting sensor 16 to detect the bottom dead point position of a sliding part 3 and the arithmetic control part 8 to perform the control of a slide driving part 7 based on the output signal SA transmitted from this detecting part. The position detecting sensor 16 is induced to the approaching proximity plate 19, the detecting signal SA is outputted to a peak value holding circuit 21 via amplifier 20, the peak value to show the bottom dead point is held, the signal SB to show the peak value is inputted into A/D convertor 22, the signal SB is converted into A/D and the digital signal SC is inputted into microcomputer 23. The computer 23 calculates the difference DELTAP between the bottom dead point position P and reference bottom dead point position PO. And if the difference DELTAP shows positive, namely the bottom dead point shows a rising tendency the control signal SM such as increasing the press speed by 50spm in case of rising about 30mum, for instance is impressed on a motor part 12 by the preset empirical formula. |
